KOGNITIVE
NEUROPHYSIOLOGIE DES
MENSCHEN
HUMAN COGNITIVE
NEUROPHYSIOLOGY
© 2012 W. Skrandies, Aulweg 129, D-35392 Giessen
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Herausgeber: Wolfgang Skrandies
© 2012 W. Skrandies, Aulweg 129, D-35392 Giessen
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A. Fallgatter, Tübingen
T. Koenig, Bern
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ISSN 1867-576X
ii Human Cognitive Neurophysiology 2012, 5 (1)
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Pascual-Marqui, R., Michel, C., & Lehmann, D. (1994). Low resolution electromagnetic tomog-
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Zani, A., & Proverbio, A. (Eds.). (2002). The Cognitive Electrophysiology of Mind and Brain.
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iv Human Cognitive Neurophysiology 2012, 5 (1)
Inhalt — Contents
Inhalt — Contents
D. Eckstein, T. Koenig, M. Wyss, & W. J. Perrig — Monitoring the Time Course of
Perception without Awareness . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
M. Wagner & W.-J. Kuo — Population-Adapted Averaged Head Templates . . . . . . . 22
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften und der ana-
lytischen Philosophie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting . . . . . . . 61
M. Doppelmayr – Neurobiologie der Psychotherapie (Buchbesprechung) . . . . . . . . 82
Announcements — Ankündigungen . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
2012, 5 (1) Kognitive Neurophysiologie des Menschen v
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
Abstract
D. Eckstein, T. Koenig, M. Wyss, & W. J. Perrig (Bern, Switzerland) — Monitoring the Time Course
of Perception without Awareness: A Comparison of Mirror Masked Words and Nonwords
Mirror masked words are embedded into a context that makes them appear as senseless patterns or as
strings of unfamiliar letters. Thus, mirror masked words can be shown for several hundreds of milliseconds
without being recognised as words. We sought to further investigate effects of nonsconscious reading by
monitoring event-related brain potentials (ERPs) while participants observed mirror masked letter strings.
ERPs were recorded while participants observed mirror masked words and nonwords. Data of 15 partici-
pants was segmented into periods of quasi-stable field topography (microstates). Microstates for masked
words and nonwords were compared using randomization tests, statistical parametric scalp maps and Low
Resolution Electromagnetic Tomography (LORETA).
ERPs to masked words and nonwords showed significant topographic differences between 136 and 256
ms, indicating that stimuli were nonconsciously discriminated. A LORETA model localised sources of
activation discriminating between masked words and nonwords in left operculum, the right superior pari-
etal lobe and right superior temporal gyrus indicating higher current density for nonwords than for words
in these areas.
ERPs of mirror masked stimuli can indicate unconscious discrimination even in cases where behavioural
priming is unreliable. This approach might be useful for investigating differences in early, nonconscious
stages of word perception.
Keywords: Reading; Language; Subliminal perception; ERPs; LORETA
Monitoring the Time Course doris.eckstein@psy.unibe.ch
of Perception without
Awareness: A Comparison of Introduction
Mirror Masked Words and In the past few years, research on perception
without awareness has obtained consider-
Nonwords able attention in cognitive science. Effective
masking techniques have been developed
D. Eckstein∗1,4, T. Koenig∗2,4, M. Wyss,∗3 & W.
with which stimuli can be presented sublimi-
J. Perrig∗1,4 1Department of Psychology,
nally. Priming experiments with subliminally
University of Bern, 3000 Bern 9, 2Department of
Psychiatric Neurophysiology, University Hospital of presented words and letter strings have been
Psychiatry, ,3Teacher Training University of Central successfully used to investigate processing
Switzerland (PHZ), Lucerne, 4Center for Cognition, of linguistic properties of words (cf. Frost,
Learning, and Memory, University of Bern, Bern, Forster, & Deutsch, 1997; Grainger, Colé,
Switzerland & Segui, 1991; Kinoshita & Lupker, 2003),
2012, 5 (1) Kognitive Neurophysiologie des Menschen 1
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
effects of attitudes and emotional content fects can be quite robust when using this strat-
(cf. Bargh, 1992; Hassin, Uleman, & Bargh, egy (cf. Greenwald, Draine, & Abrams, 1996;
2006; Wentura, 2002) and effects on memory Greenwald, Klinger, & Schuh, 1995), which ex-
(e.g., Jacoby & Whitehouse, 1989). The usual plains why existing fMRI studies on subliminal
method of masking is to embed to-be-masked perception have been based on this approach
stimuli in a rapid visual stream of pattern (e.g., Dehaene, Naccache, Cohen, & Rivière,
masks. This combination of short stimulus 2001; Dehaene, Naccache, Le Clec'H, & Le
duration and overlapping visual percepts of Bihan, 1998; Naccache & Dehaene, 2001).
stimulus and masks leads to the visual expe- However, it has become evident that frequently
rience that the stimulus is invisible. However, repeating the same set of stimuli with fixed re-
this method only works within a narrow range sponse mappings leads to automatisation of all
of possible presentation times that exclude processes involved in responding. As a conse-
awareness of stimuli. It has also been noted quence, processes of perception, memory and
that the onset of a mask that follows a stimulus response preparation become difficult to sep-
has the effect of interrupting any bottom-up arate (Damian, 2001; Kunde, Kiesel, & Hoff-
processing of the stimulus up to that point mann, 2003). This issue is further complicated
(Humphreys, Besner, & Quinlan, 1988; Ko- by the fact that the threshold of consciousness
vacs, Vogels, & Orban, 1995; Rolls & Tovee, decreases with repeated presentation (Wol-
1994). Because of its tight limits, the timing ford, Marchak, & Hughes, 1988), which can
must ideally be empirically determined on an lead to paradoxical priming effects, e.g. ef-
individual basis for every participant in a given fects that appear to be related to the mean-
experiment. ing of stimuli but are instead driven by low-level
perceptual properties of the stimuli (Abrams &
Another difficulty arises from the fact that Greenwald, 2000; Greenwald, Abrams, Nac-
subliminal perception must be indirectly in- cache, & Dehaene, 2003; Kouider & Dupoux,
ferred from participants’ reactions. Earlier at- 2004).
tempts to use direct measures (whereby par-
ticipants were asked to indicate which word in To overcome these methodological difficul-
a list appeared beforehand) have suffered from ties of delicate timing issues or small effect
unreliability, which explains why indirect mea- sizes, we developed a masking method that
surements based on priming are commonly does not rely on temporal masking, but in-
used. The actual paradigmatic measurement stead uses spatial masking (Perrig & Eckstein,
of subliminal perception consists in assessing 2005). This masking technique, which we call
priming by subliminal primes on reactions to mirror maskingüses each letter’s mirror image
succeeding visible probes. These priming ef- to mask the word. As can be seen in Figure 1,
fects are not as large, and thus more difficult letters are merged with their inverted counter-
to replicate than priming effects obtained with part at the letters' base line. In previous exper-
visible primes. One way to increase the ef- iments of ours, mirror masking has proven ef-
fect size is to familiarise participants with the fective in hiding prime words (that were shown
test material used in the task. Indeed, ef- for 750 ms) from awareness: Across a range
2 Human Cognitive Neurophysiology 2012, 5 (1)
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
of unpublished and published experiments with that perception of words does not reach the
over 200 participants, 85% of participants re- semantic level, as semantic priming was found
ported not having perceived any of the prime to depend on participants’ reading ability (cf.
words after the experiment (Perrig & Eckstein, Eckstein, Norris, Davis, & Henson, 2009).
2005). The masking effect is in principle due Our previous studies thus indicate that mirror
to a visual neglect driven by attentional diver- masked words are unconsciously processed
sion, thus resembling the phenomenon of 'inat- at a nonsemantic lexical level. Therefore, they
tentional blindness' (Mack & Rock, 1998). The can be used as a tool to investigate the mech-
fact that the mirror masked letters form new anisms of nonconscious perceptual and lexical
symmetrical patterns resembling an unknown word perception that is not accompanied by
alphabet further enhances the masking effect. awareness.
Indeed, when participants start seeing words
in the patterns, they are usually unable to de- In all experiments so far, behavioural prim-
scribe the masking at first, because the words ing by masked words was weak. This is a
tend to be seen as ’popping out’ of the pat- usual finding in this field, when one uses
tern. Due to its different mode of functioning, non-repeated word presentation (cf. Damian,
mirror masking has two outstanding advan- 2001). The present study was conducted be-
tages compared to pattern masking: (a) Re- cause ERP measures have been found to be
ports of conscious perception do not depend more sensitive to nonconscious priming than
on response criterion levels, because words behavioural priming (e.g., Holcomb, Reder,
are seen as popping out as a whole, and (b) Misra, & Grainger, 2005; Kiefer, 2002; Misra &
presentation time is in principle not critical. Holcomb, 2003). The main idea was to locate
temporal and topographic differences in ERPs
We have previously observed replicable recorded while participants observed masked
priming of mirror masked primes with the word words and nonwords. This approach is usually
stem completion task and, less reliably, with difficult to do because ERPs of the masked
the lexical decision task. In word stem comple- stimulus interfere with ERPs of the succeeding
tion, where participants are asked to complete nonmasked stimulus in priming studies. In-
a 3-letter word onset with two or three letters stead, we were able to present mirror masked
such that a valid word is formed, masked prime words for 500 ms, which allowed us for on-line
words that were only shown once in an exper- monitoring of processes occurring while partic-
iment were reliably completed more often than ipants fixed the masked letter strings. Because
control words, and this effect remained stable we could not assume to find the same ERP
over stimulus onset asynchronies (SOAs) of 1 components for nonconscious perception as
to 3 seconds (Perrig & Eckstein, 2005). Sub- the ones reported for conscious word percep-
sequent studies suggested that priming is not tion (cf. Compton, Grossenbacher, Posner,
due to single letters or word-parts, because & Tucker, 1991; Grossi & Coch, 2005; Hino-
completion of words was not facilitated by sub- josa, Martin-Loeches, & Rubia, 2001; Nobre &
strings of primes (Eckstein, Sturzenegger, & McCarthy, 1995; Schendan, Ganis, & Kutas,
Perrig, in preparation). However, it is possible 1998; Sereno, Rayner, & Posner, 1998, for
2012, 5 (1) Kognitive Neurophysiologie des Menschen 3
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
Figure 1: Example of the mirror masked term ’mirror nonwords’. Construction of mirrored letters is
illustrated in the upper part of the figure. In the lower part, examples of mirrored nonwords (left, from
top: ”skofe”, ”neibs”, ”weethce”, ”ruiohs”, ”ararlon”, ”druimed” and ”orulkce”) and words (right, from
top: ”berth”, ”autumn”, ”liver”, ”success”, ”heaven”, ”irritation” and ”chance”) are reproduced. Note:
The original language used was German.
prelexical processing; Cohen et al., 2000; tween stimuli, can only be done with extreme
Martin-Loeches, Hinojosa, Gomez-Jarabo, caution.
& Rubia, 1999; Nobre, Allison, & McCarthy,
1994; Rudell & Hua, 1997; Skrandies, 1998 Analysis was based on comparisons of ERP
for discrimination of word-forms or retrieval scalp topographies across conditions in differ-
from word lexicon; Brown, Hagoort, & Chwilla, ent time segments, using the microstate ap-
2000; Dietrich et al., 2001; Holcomb, et al. proach. The time course of ERP topographies
2005; Kutas & Hillyard, 1980; McCarthy, No- contains periods of relative stability during
bre, Bentin, & Spencer, 1995; Wirth et al., which change across time is minimal. These
2006 for semantics, but see Penolazzi, Hauk, periods of quasi stable ERP topography have
& Pulvermüller, 2007), we used the microstate been called ’microstates’ and are thought
and the TANOVA methods, which are both to correspond to basic steps of information
apt for explorative determination of significant processing (Lehmann, 1990). Because it is
differences in ERP topographies between time sensible to collapse across similar data from
segments and conditions (McCarthy et al., a statistical point of view, on- and offset times
1995). Therefore, comparison with findings of microstates were used to define time win-
stemming from research with visible words, dows of analysis. Using a bootstrap method,
according which differences at about 200 ms comparison of microstate topographies across
would be expected with lexical differences be- conditions was then used to locate differences
in active cerebral generators.
4 Human Cognitive Neurophysiology 2012, 5 (1)
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
The experiment consisted in priming task Stimuli
using lexical decision, whereby each visible
probe (word or nonword) letter string was pre- 180 non-associated word pairs were selected
ceded by a mirror masked (word or nonword) from a set of German nouns, most of which
letter string shown for 500 ms. This was done described concrete and emotionally neutral
to ensure that participants were looking at the concepts. Word length varied between 3 and
masked stimuli when they appeared on the 8 letters and between 1 and 3 syllables. Or-
screen, although their attention was directed thographic similarity of words in word pairs
towards the succeeding probes. On the basis was very low as measured by an index of
of a previous unpublished experiment, we ten- orthographic similarity described in Weber,
tatively expected priming effects for word-word 1970. This set of word pairs was divided
compared to nonword-word trials which would into four groups of 45 word pairs that were
indicate lexical processing of the primes. In balanced with respect to word length, number
order to rule out other reasons for such prim- of syllables, orthographic similarity and word
ing, orthographic and semantic relatedness of frequency (Institut für Deutsche Sprache,
masked and visible stimuli was minimised and 1991-2007), based on occurrences in Swiss
every stimulus was shown only once during the Newspaper texts. Nonwords were constructed
experiment. by concatenating letters that were randomly
selected from each letter position of the ex-
perimental word set. 180 nonwords were
Materials and Methods constructed on the basis of the first word in
the word pairs, and another 180 nonwords
Subjects were constructed in the same way based on
the second word in the word pairs. Hence,
Participants were 8 male and 11 female vol-
letter frequencies of words and nonwords
unteers aged 21 to 38 years (M = 28.5, SD
were identical at each letter position. Pairings
= 5.7). They were all native German speak-
of masked and nonmasked stimuli were con-
ers with normal or corrected-to-normal vision,
trolled. The four groups of word pairs were
without any neurological or neuropsychologi-
counterbalanced over participants and the
cal disorder and without psychoactive medica-
four possible pairing conditions (masked word
tion. 16 participants were self-reported right-
vs. nonmasked probe word, masked nonword
handers and 3 were ambidextrous. All partic-
vs. nonmasked probe word; masked word vs.
ipants were naïve to the experimental hypoth-
nonmasked probe nonword, masked nonword
esis, had never been in contact with the mirror
vs. nonmasked probe nonword). Additional 15
word masking paradigm and were naïve with
nonwords and 5 words were used for practice.
respect to priming paradigms. The study was
approved by the University’s ethics committee
and informed consent was obtained from all Procedure
participants.
Participants were comfortably seated in
a darkened, acoustically and electrically
2012, 5 (1) Kognitive Neurophysiologie des Menschen 5
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
shielded recording chamber. A 15”’ liquid rored font. Sequence of the 180 trials was
display VGA screen and an IBM compatible randomized. Each participant saw 45 stimu-
personal computer was used for stimulus dis- lus pairs in each of the four conditions of word-
play. Participants were seated at a distance nonword combinations, whereby word groups
of about 50 cm from the screen, their heads were rotated between conditions and partici-
positioned by a head-rest mounted on a small pants, and nonwords were randomly chosen
table in front of them. Left and right keys of from the nonword set. Each word and non-
a button box were used with the index fin- word in the stimulus set was shown maximally
gers of the left and right hand for collection once during the experiment. A short break was
of responses. The experimental program was given after 60 and 120 trials.
written in MEL 2.0 (Schneider, 1988). At the end of the experiment, participant’s
10 practice trials and 180 experimental trials awareness of the masked words was as-
were shown. Each trial had a fixed sequence sessed with three consecutive questions: Had
starting with a 1s blank screen which was fol- they noticed anything unusual in the patterns?
lowed by a 500 ms mirror masked stimulus, Had they seen single letters in them? And, had
then a 500 ms blank screen, and finally a 500 they seen words in them? These questions
ms nonmasked probe stimulus. The response were used to determine which of the partici-
window started at probe onset and lasted for pants were not aware of the words throughout
one second. Inter-trial interval duration was the whole experiment.
one second. Participants were instructed to
fixate the centre of the screen, where an ab- Electrophysiological Recording
stract pattern (the masked letter string) would
EEGs were recorded by 74 Ag/AgCl scalp
indicate the imminent onset of the letter string
electrodes mounted on an elastic cap accord-
probe. They were asked to press as quickly as
ing to the international 10-10 system. To
possible the key corresponding to the type of
record eye blinks, two additional electrodes
probe shown. Right and left button box keys
were placed below the eyes. Cz was used
were alternatively assigned to word and non-
as recording reference. Electrode impedances
word probes across participants. Participants
were held below 10 kOhm. Signals were am-
were also instructed to keep eye movements
plified, bandpass filtered at 0.5-70 Hz, digi-
and eye blinks to a minimum during trials.
tized at 250 Hz and continuously stored for of-
All stimuli were presented at the centre of fline analysis. Stimulus onsets were recorded
the screen in white lettering on a black back- with a separate channel appearing in the EEG
ground. The mirrored letter strings were pre- recordings.
sented in mirror masked lower-case letters
written in 'boxie17' font, subtending a vertical
EEG preprocessing and averaging
visual angle of about 1°and a horizontal vi-
sual angle of about 4°. Probe letter strings From the raw EEG data, electrooculograph-
were presented in upper-case in 'FG-16' (MEL ical signals (EOG) were computed as bipo-
font) which had the same height as the mir- lar derivations between F9 and F10 (horizon-
6 Human Cognitive Neurophysiology 2012, 5 (1)
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
tal EOG) and the channels below the eye determine on- and offsets of the microstates
against Fp1 and Fp2 (vertical EOG). All 74 used for further analysis. Microstates that had
scalp channels were recomputed to average an on- or offset at the beginning or ending of
reference. After applying a 50 Hz notch filter the 0 to 500 ms post-stimulus analysis period
and a 1.5 to 30 Hz bandpass filter, the analy- were not further analysed. For illustration pur-
sis epochs were selected, starting at the onset poses, stability of microstates between GFP
of each stimulus and lasting for 500 ms. (After troughs was further quantified by computing
500 ms, eye movements were more frequent). the matrix of spatial correlations across time
These epochs were DC corrected (baseline re- (Kochi, Koenig, Strik, & Lehmann, 1996).
moval) and submitted to a semi-automatic ar-
tifact detection that rejected epochs with chan- Comparison of the ERPs
nels showing peak to peak amplitudes larger
than 100 uV within 100 ms and artifacts iden- Statistical comparisons of word and nonword
tified by visual inspection. Over participants, ERPs across subjects were done separately
the rate of rejection due to artifacts was about for masked and nonmasked stimuli. Separate
10%. For each subject, separate mean ERPs analyses were conducted for comparison of
were computed for masked nonwords, masked microstate amplitude and topography in each
words, nonmasked nonwords and nonmasked microstate time window. For each subject and
words. For each of these four conditions, a condition, individual mean microstate topogra-
grand-mean across all participants was com- phies were first computed. Differences be-
puted. tween microstate amplitudes associated with
words and nonwords were tested with paired
two-tailed t-tests over subjects on GFP (statis-
Identification of microstates
tical parametric scalp maps).
Identification of microstates was based on For the comparison of microstate topog-
Global Field Power (GFP) of the grand-mean raphy between word and nonword condi-
ERPs for masked and nonmasked stimuli, tions, a randomization statistic was applied
respectively (Lehmann & Skrandies, 1980). using the 'TANOVA' program (available on-
Separate microstate analyses were done line at www.unizh.ch/keyinst/ NewLORETA/
based on the post-hoc observation that the LORETA01.htm). Using Global Map Dissimi-
GFP time course and the topographies of larity (Lehmann & Skrandies, 1980) as a GFP-
the grand-mean ERPs were substantially dif- independent difference measure between con-
ferent. GFP is a momentary, global index of ditions, TANOVA applies a randomization test
topographic strength and is defined as the spa- (Edgington, 1980; Manly, 1997) to establish
tial standard deviation. Periods of high GFP the exact probability of the observed difference
assumingly correspond to near-synchronous by assuming a null hypothesis of zero topo-
activity of neural populations, and changes graphic dissimilarity. This procedure has been
of ERP topography typically occur in local used in earlier studies (Kondakor, Pascual-
troughs of the GFP (Lehmann, 1986). We Marqui, Michel, & Lehmann, 1995; Lehmann
therefore used the troughs of the GFP curve to et al., 2005; Strik, Fallgatter, Brandeis, &
2012, 5 (1) Kognitive Neurophysiologie des Menschen 7
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
Pascual-Marqui, 1998). In microstates where cluded from all subsequent analyses. All other
TANOVA indicated a topographic difference participants reported that they did not notice
at p <.05, further analyses were performed: anything unusual in the patterns and that they
Firstly, t-maps were computed, thresholded had seen no letters or words in them. When
at p < .05 (uncorrected) and displayed for asked about the mirror masked strings, some
comparison with other studies (note that these of these participants guessed that they were
t-values were not used for further statistical strings of an unknown writing, as for instance
interference, since the null-hypothesis was hieroglyphics. All analyses were performed
rejected by the TANOVA). Secondly, since on the data of these remaining 15 participants
evidence for a topographic difference implies who were ignorant of the information hidden in
that there must have been differences in the mask. Response accuracy was reasonably
the underlying sources, a distributed source high, with 95% correct responses for words
localization procedure was employed to lo- (SD = 3%) and 92% correct responses for non-
cate these putative intracerebral sources of words (SD = 5%). Average reaction times were
significant differences. faster for words, M = 579 ms (SD = 55 ms),
Source localization was based on low reso- than for nonwords, M = 639 ms (SD = 75 ms),
lution electromagnetic tomography (LORETA, t(14) = 7.09, p < .001. No effect of priming was
Pascual-Marqui et al., 1999; Pascual-Marqui, found when comparing masked-string/visible
Michel, & Lehmann, 1994) applied to indi- string pairs that where congruent vs. incon-
vidual, normalized (maximum GFP = 1) mi- gruent in lexicality (e.g., word-word and non-
crostate topographies of both included stim- word/nonword vs. nonword-word pairs; effect
ulus conditions. This version computed the of type of masked string, F(1,14) = 0.62, p >
electric current density in the cortical areas of .20 and interaction of type of masked string
the digitized brain atlas of the Montreal Neu- with type of visible string, F(1,14) = 1.95, p =
rological Institute (MNI) at ˜7 mm resolution .18).
(2394 voxels). In those microstates where
the TANOVA indicated significant differences Masked Words and Nonwords
of ERP topography between conditions, voxel-
by-voxel t-statistics were used to identify those Segmentation of grand mean ERPs yielded
voxels that could putatively account for the dif- 3 microstates. Microstate topographies, mi-
ferences observed on the scalp. For illustra- crostate latencies and GFP time course for
tion purposes, the highest threshold of the t- masked stimuli are shown in upper part of
statistics was set at an alpha level of 5%. Fig. 2. The stability of microstates was further
quantified with spatiotemporal correlation ma-
trices of ERPs averaged across subjects and
Results conditions (Fig. 3, left).
Behavioral Data The first microstate was a P100 topography
with a bilateral occipital positivity (88-136 ms).
Four participants saw at least one word in the This was followed by a N200 that displayed
masked letter strings and were therefore ex- an occipital bilateral negativity and a fronto-
8 Human Cognitive Neurophysiology 2012, 5 (1)
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
Figure 2: Topographies and latencies of the microstates identified in the grand mean ERPs for masked
(upper graph) and nonmasked stimuli (lower graph). Each graph shows the mean microstate topographies,
head seen from above; red indicates positive, blue negative values, referred to average reference. The
topographies were scaled to maximal Global Field Power (GFP) = 1. The curve in each graph shows
the GFP (vertical) of the ERPs as function of time (horizontal). Microstate borders were set at the local
minima of the GFP curve (indicated by the vertical lines).
2012, 5 (1) Kognitive Neurophysiologie des Menschen 9
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
Figure 3: Illustration of stability of topographic maps over time. Both axes indicate time with respect
to stimulus onset. Spatial correlations of ERP signals across time are shown for masked (left) and non-
masked (right) stimuli. Red areas correspond to positive correlations, and blue areas indicate negative
correlations. Color saturation indicates strength of correlation. During dark red time segments (indicat-
ing inter-correlations higher than .9), topographies were stable.
10 Human Cognitive Neurophysiology 2012, 5 (1)
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
central positivity (136-256 ms). A third mi- Comparison of GFP differences between
crostate was characterized by a bilateral pari- word and nonword stimulus microstates indi-
etal positivity and a fronto-central negativity cated no significant GFP differences between
(256-404 ms). words and nonwords. The randomization test
Comparison of GFP differences between of topographic dissimilarity indicated signifi-
word and nonword stimulus microstates indi- cant differences of microstate topographies in
cated no significant GFP differences between the 32-140 ms microstate (p = .027), the 200-
words and nonwords. The randomization test 252 ms microstate (p = .008) and the 324-
of topographic dissimilarity however indicated 404 ms microstate (p = .005). T-maps of the
significant differences of microstate topogra- microstates with significant topographic differ-
phies in the 136-256 ms microstate (p = .034, ences are shown in Fig. 4.
cf. Fig. 4). According to the LORETA model, differ-
Results of the voxelwise comparisons of ences between words and nonwords in the
LORETA solutions in microstates with word- 32-140 ms segment were localized in right lat-
nonword topographic differences are shown in eral fusiform gyrus, left mediotemporal gyrus
Fig. 5 and Table 1 (see also the supplementary and right superior frontal gyrus. During the
material). According to the LORETA model, 200-252 ms segment, differences were found
differences between masked words and non- in right temporal lobe, left temporal lobe, left
words between 136 and 256 ms were related posterior cingulate, right frontal operculum
to higher current density for nonwords than for and left superior occipital lobe. Between 324
words in left operculum, right superior parietal and 404 ms, differences were found in right
lobe and right superior temporal lobe (first row orbitofrontal area, right superior frontal lobe,
in Figure 5). left middle temporal gyrus and right middle
fusiform gyrus (Table I).
Nonmasked words and nonwords
Discussion
Grand mean ERPs and segmentation is
shown in Figures 2 and 3. Five microstates This study investigated ERP time course of
were identified: A first microstate was a P100 mirror masked words and nonwords that were
with a bilateral occipital positivity (32-140 ms), not recognised by participants. Sequences of
which was followed by a N200 that displayed stable microstates were analysed, which are
a strong occipital bilateral negativity and a thought to reflect successive stages of word
fronto-central positivity (144-200 ms). Then, processing that correlate with successive acti-
two microstates followed that lasted from 200 vation of functional brain areas (Koenig, Kochi,
to 252 ms and from 256 to 320 ms, during & Lehmann, 1998; Koenig & Lehmann, 1996;
which the posterior negativity expanded over Michel et al., 2001; Pegna, Khateb, Michel, &
central and left parietal sites. A fifth microstate Landis, 2004).
from 324 to 404 ms was characterized by large Based on findings of earlier studies, differ-
negativity extending over midline and frontal ences between words and nonwords should
electrodes. appear in the 100-200 ms segment with vis-
2012, 5 (1) Kognitive Neurophysiologie des Menschen 11
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
Figure 4: Upper row: Mean microstate maps, scaling as in Fig. 3. Lower row: Statistical parametric
scalp maps for those microstates that showed significant topographic differences in the randomization
tests. Blue areas indicate larger values in the nonword condition; red areas indicate larger values in the
word condition. Increasing steps of color intensity indicate p values below .10, .05 and .01, respectively.
Figure 5: Glass brain images of voxels showing differences between words and nonwords (p < .05), darker
voxels indicate higher t values.
12 Human Cognitive Neurophysiology 2012, 5 (1)
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
Table 1: Results of the voxelwise comparisons of LORETA solutions
Area at
Segment Brodmann
Left/right maximal MNI Coordinates t-Value
(ms) Area
t-Value
X Y Z
Higher source activation for words than for nonwords
Nonmasked Stimuli
Lateral
32-140 R 37 53 -53 -13 3.58
fusiform
Middle
L 21 -52 -11 -13 3.42
temporal
Superior
R 10 25 59 29 3.00
frontal
Frontal
200-252 ms R 45,44 60 17 22 2.50
operculum
Superior
L 7 -24 -81 43 2.37
occipital
324-404 R Orbitofrontal 25 11 10 -20 4.06
Superior
R 8 18 31 50 3.71
frontal
Higher source activation for nonwords than for words
Masked Stimuli
136-256 L Operculum 43 -66 -11 22 -2.98
Superior
R 40 46 -46 43 -2.62
parietal
Superior
R 22/41 46 -18 1 -2.32
temporal
Nonmasked Stimuli
Inferior
200-252 L -31 -32 -6 -3.57
temporal
Superior
R 22/41 53 -18 8 -2.70
temporal
Posterior
L 31 -3 -25 36 -2.16
cingulate
Middle
324-404 L 21 -59 -32 -13 -3.42
temporal
Middle
R 37 32 -46 -20 -2.92
fusiform
Superior
L 7 -24 -67 57 -2.35
parietal lobe
2012, 5 (1) Kognitive Neurophysiologie des Menschen 13
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
ible words. Indeed, ERP differences of vis- of the words in the masked patterns, these
ible words vs. nonwords were found in a ERP differences suggest that some word-
P100 microstate located on the left parieto- related properties of masked stimuli were
occipital lobe which is known to reflect font, unconsciously processed. This segment of
letter and n-gram differences (Compton et al., 132 to 256 ms after stimulus onset was used
1991; Nobre et al., 1994; Sereno et al., 1998), for further analysis to identify the processes
and is associated with foci wandering from the differentiating between masked words and
occipital lobe to posterolateral fusiform gyrus nonwords. First, ERPs averaged over the
(Binder & Price, 2000; Fujimaki et al., 1999; whole time segment of interest were anal-
Gernsbacher & Kaschak, 2003; Petersen, Fox, ysed. Difference maps formed a characteristic
Snyder, & Raichle, 1990; Pugh et al., 1996; pattern of focused temporo-parietal positivity
Tarkiainen, Helenius, Hansen, Cornelissen, on the left hemisphere (Fig. 4). This pattern
& Salmelin, 1999) and sometimes also com- bore resemblance with left-lateralised pos-
bined with frontal areas (Hauk, Davis, Ford, itivity around the temporo-occipital junction
Pulvermuller, & Marslen-Wilson, 2006). Just related to orthography which is discussed to
after the 200 ms point which appears to be be associated with N170 (Bentin, Mouchetant-
a marker of lexical access, significant word- Rostaing, Giard, Echallier, & Pernier, 1999;
nonword ERP differences were found in a seg- Salmelin, Service, Kiesila, Uutela, & Salonen,
ment ranging from 200 to 252 ms. The differ- 1996, although this was reversed for nonwords
ence map resembled regressor maps associ- vs. words in our case), and parietal positivity
ated with word frequency reported by Hauk et related to word frequency and lexicality (P3,
al. (2006). Word frequency is closely related to Proverbio, Vecchi, & Zani, 2004). Hence,
word familiarity, which might have been used to there were some similarities of masked stim-
discriminate words from nonwords in our study. ulus word-nonword differences and ERPs of
The late differences in the 324 to 404 ms seg- visible stimuli as reported in the literature.
ment were reasonably in agreement with find-
ings related to postlexical and semantic pro- In a second step, LORETA distributed
cessing of words that are associated with pos- source solution for this left lateralized positivity
terior negativity for words vs. nonwords, which for masked words vs. nonwords was com-
is seen with frontal lobe, middle temporal gyrus puted (cf. Fig. 5). Results suggested that the
and medial fusiform activation. difference in topographies was due to stronger
current density for nonwords than for words in
The topographic ERP-differences with two right hemisphere areas (superior temporal
masked strings were different. Significant lobe, superior parietal lobe) and in one left
differences between stable ERP topographies hemisphere area (posterior operculum near
when participants observed masked words the Sylvian fissure). Activation in middle and
compared to when they observed masked superior temporal lobe has frequently been
nonwords were found in a time segment from found with word vs. nonword comparisons,
136 to 256 ms after stimulus onset. Assuming although the activity tends to be left lateralised
the study participants validly were not aware or bilateral (Cohen et al., 2000; Nobre et al.,
14 Human Cognitive Neurophysiology 2012, 5 (1)
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
1994; Salmelin et al., 1996; Schendan et al., cesses that are known to occur in the 136 to
1998). Why the modelled temporal sources 256 ms time range or earlier components that
are localized in the right hemisphere is difficult were delayed, but we infer this with caution, as
to explain on the basis of the present results. the temporal and parietal activation appeared
It is not unusual to assume that language to be in the right but not in the left hemisphere.
processing is bilateral but that activity is often Although LORETA source models are not
stronger in the left hemisphere (cf. Damasio, suited to make direct inferences as to which
Tranel, Grabowski, Adolphs, & Damasio, 2004; processes are responsible for word-nonword
Scott & Wise, 2004). As one possible explana- ERP differences, it is possible to compare
tion, we suggest that unconscious processing LORETA solutions for different conditions in
of words might recruit language areas in a order to identify similarities and differences
different fashion than visible words, leading in modelled brain activations. Therefore, the
to measurable activation in the right hemi- masked stimuli LORETA solution for ERPs av-
sphere (e.g., Grossi & Coch, 2005; Holcomb & eraged over the 136 to 256 ms time seg-
Grainger, 2006). Another possible explanation ment was compared with the nonmasked stim-
might be that the activity results from an inhi- uli LORETA solution for ERPs averaged over
bition of word processing due to the masking. the 200 to 252 ms time segment (cf. Fig. 4).
Such inhibition has been observed previously There was a small area of overlap in right su-
in masking studies (Eckstein, Kubat, & Perrig, perior temporal lobe which discriminated be-
2011; Wentura & Frings, 2005). The other two tween words and nonwords for masked as well
areas, i.e. parietal lobe and posterior opercu- as for nonmasked stimuli (maximal t values
lum, have also occasionally been reported to at MNI coordinates 46/-18/1 and 53/-18/8 for
differentiate between words and nonwords or masked and nonmasked stimuli, respectively).
pseudowords (Compton et al., 1991; Hauk et We tentatively suggest that this overlap repre-
al., 2006; Salmelin et al., 1996). It is however sents a common process that was active in this
unusual to find higher activation for nonwords time range, whereas the non-overlap of other
than words, especially in language areas in areas indicate that most processes differenti-
the left hemisphere. Given that the primes ating between words and nonwords were not
were not readable for the participants, it is shared when observing masked compared to
possible that this difference in activity just nonmasked stimuli in this specific task.
represents a difference in resource allocation
or in timing. That is, higher allocation of re- In summary, differences were found be-
sources was needed to convert substrings of tween ERPs of masked words and ERPs of
nonword primes to phonemes than for word masked nonwords, and the source of these
primes and such a decoding probably took differences was located in an area that was
longer for nonwords than for words, which also found as source with visible words and
would explain the late timing. The sources of nonwords. Compared to visible stimuli how-
activation found with the LORETA model could ever, differences were small. Given that mirror
thus tentatively reflect word recognition pro- masked patterns look like nonsense patterns
or unknown hieroglyphs, ERPs measured
2012, 5 (1) Kognitive Neurophysiologie des Menschen 15
D. Eckstein et al. — Monitoring the Time Course of Perception without Awareness
while participants see mirror masked words sentation durations.
primarily reflect processes that lead to the
conscious experience of seeing nonsense pat- Acknowledgements
terns. It is therefore not surprising that most of
the ERP differences found between words and D. Eckstein and T. Koenig contributed in equal
nonwords are different for masked compared parts to this study. The authors thank Antje
to nonmasked stimuli. The task used did not Heinrich, Rik Henson and Susanne Jaeggi for
require lexical processing of the mirror masked valuable comments on an earlier version of this
stimuli. Nevertheless, some of the processes article. Part of this work was funded by Swiss
involved in perception of masked stimuli ap- National Foundation Fellowship No PA001 -
peared to differentiate between words and 113106/1.
nonwords, indicating that some aspects of
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2012, 5 (1) Kognitive Neurophysiologie des Menschen 21
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
Abstract
M. Wagner & W.-J. Kuo (Hamburg, Germany & Taipei, Taiwan) – Population-Adapted Averaged
Head Templates for EEG and MEG Source Analysis
In electroencephalography or magnetoencephalography source localization studies where individual sub-
ject’s magnetic resonance images (MRIs) are not available, averaged MRIs can be used instead. For pop-
ulations of subjects with head shapes that are both homogeneous and sufficiently distinct from the head
shape of an existing averaged MRI, the use of a population-adapted, averaged MRI is desirable. Examples
for such populations are non-Caucasian or pediatric subjects. A population-adapted, averaged MRI can
be created based on individual MRIs of subjects representing the population of interest. The extents of the
bounding box containing the brain, together with the locations of the anterior and posterior commissure
landmarks are measures facilitating this process. Based on their average values for the individual MRIs, it
is possible to average these individual MRIs. Alternatively and also based on these measures, an existing
averaged MRI can be adapted to better match the population’s head shape. Based on individual MRIs of
62 Chinese subjects, the procedure is demonstrated, including the creation of standard electrode locations
and realistically shaped boundary element method head models.
Keywords: Magnetic resonance imaging; Electroencephalography; Magnetoencephalography; Source
localization; Averaged MRI; Talairach Co-registration
Population-Adapted Introduction
Averaged Head Templates for
EEG and MEG Source In electroencephalography (EEG) and
magnetoencephalography (MEG) source anal-
Analysis ysis, medical image data such as magnetic
resonance images (MRIs) can be utilized in
∗ a variety of ways. Localization accuracy isM. Wagner 1, W.-J. Kuo∗2
increased by means of individual, realistically
1Compumedics Germany GmbH, shaped head models (Fuchs, Drenckhahn,
Heußweg 25, 20255 Hamburg, Germany, Wischmann, & Wagner, 1998; Mosher, Leahy,
2Institute of Neuroscience, & Lewis, 1999). Source analysis results can
National Yang-Ming University, Taipei, Taiwan be displayed in their anatomical context by
mwagner@neuroscan.com overlaying them onto structural brain mages
such as MRI (Fuchs, Wagner, Wischmann,
Ottenberg, & Dössel, 1994). Furthermore,
anatomical features such as the gray matter
22 Human Cognitive Neurophysiology 2012, 5 (1)
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
may be used to constrain source analysis gray matter, or to relate source analysis results
(Dale & Sereno, 1993; Wagner, Fuchs, Wis- to atlas information.
chmann, Ottenberg, & Dössel, 1995). Another important reference frame is the
Often, however, individual MRI data are not Talairach atlas (Talairach & Tournoux, 1988),
available or shall deliberately not be used. The which is based on axial cross-sections of a
latter can for example be the case in group single subject’s brain. It includes detailed
studies, where performing source analyses in anatomical labels. The proportional grid-
individual anatomical space and later pooling based coordinate system introduced in this
the results is more laborious than performing publication has become the de-facto standard
source analyses in a common, representative for reporting locations in the brain. The Ta-
anatomical space. In such cases, it is good lairach coordinate system is based on two
practice to use averaged MRI datasets instead landmarks, the anterior commissure (AC),
(Fuchs, Kastner, Wagner, Hawes, & Eber- which serves as the origin, and the posterior
sole, 2002; Pascual-Marqui, Esslen, Kochi, & commissure (PC), together with the extents
Lehmann, 2002): An averaged MRI dataset of the bounding box containing the brain.
(also commonly called an MRI template) The mid-sagittal and the axial plane through
shows anatomical features that are common AC and PC, together with the coronal planes
to a population of subjects, without suggesting through AC and PC, respectively, subdivide
a level of detail (cortical folds) that could only this bounding box into twelve cuboid-shaped
be obtained by using the subject’s own MRI. compartments. Using a linear transformation
An averaged MRI still makes it possible to de- per compartment, any brain, including the
rive and use realistically shaped head models, ICBM-152, can be co-registered with the Ta-
view source results in their anatomical context, lairach reference frame (Desco et al., 2001,
and constrain source analysis (albeit not to the Lancaster et al., 2007). Figure 1b shows the
level of cortical folds). Talairach bounding box overlaid onto an axial
Today, a commonly used averaged MRI is slice of the ICBM-152, while Figure 2 shows a
the ICBM-152 dataset (Mazziotta et al., 2001), 3-D rendering of the bounding box.
also called the Montreal Neurological Insti- In order to bring EEG electrode or MEG
tute (MNI) brain. It represents an average sensor locations into the anatomical reference
Caucasian head shape. A consequence of frame of an averaged MRI, a landmark-based
the widespread use of the ICBM-152 is the transformation can be applied (Fuchs, M., Wis-
availability of additional, co-registered three- chmann, Wagner, & Krüger, 1995). Alterna-
dimensional (3-D) maps detailing e.g. tis- tively, and only available in the EEG case, elec-
sue type probabilities (Mazziotta, Toga, Evans, trode locations based on the 10-20 system
Fox, & Lancaster, 1995) or cytoarchitectonic (Jasper, 1958) or one of its extensions (Cha-
atlas information (Lancaster et al., 2000; Fig- trian, 1985; Oostenveld & Praamstra, 2001)
ure 1a). This availability makes it straightfor- can be determined by measuring distances
ward to guide source analysis based on tissue on the averaged MRI’s segmented skin and
types, e.g. to constrain sources to the cortical relating their locations to the actually mea-
2012, 5 (1) Kognitive Neurophysiologie des Menschen 23
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
(a) (b)
Figure 1: (a) an axial slice of the ICBM-152 averaged T1-weighted MRI dataset with overlaid Talairach
atlas information where shades of gray encode anatomical features. (b) ICBM-152 slice with overlaid
Talairach coordinate system bounding box through the locations of AC and PC.
sured data by means of label-matching (Wag- but can only account for different overall head
ner, Fuchs, & Kohlhoff, 1996). sizes. More general shape dissimilarities be-
In EEG analysis using an averaged MRI tween individual and averaged MRI’s head
dataset, it is desirable to use electrode lo- shape still lead to errors in head modeling, re-
cations as close to the surface of the skin sult overlay, and anatomical constraints.
as possible. Else, electrode locations, head There are situations where systematic differ-
model, and the averaged MRI’s anatomy would ences between individual subject’s heads and
not match well: In the case of a (realistically a standard averaged MRI such as the ICBM-
shaped) head model based on the averaged 152 occur. This is for example the case in
MRI, electrodes need to be located on the studies involving elderly or pediatric subjects
head model’s skin surface, while in the case or subjects with psychiatric diseases, but also
of a (typically spherical) head model fitted to if non-Caucasian subjects are analyzed. In
the electrodes, source results overlaid onto the such cases, the use of an averaged MRI that is
MRI would be wrong. better suited for the subject’s heads is advised.
The underlying problem is that of a possible In this paper, we describe a procedure for
shape mismatch between the averaged MRI creating averaged MRIs for populations that
dataset and the individual subject’s head. It exhibit such systematic differences, based on
also exists in the MEG case. It is only triv- individual MRIs of subjects representative of
ial if a global spatial scaling factor suffices. the population. Such a population-specific
A global scaling factor can easily be factored averaged MRI will also be called MRI-A or
into all known head model calculations (Fuchs, MRI-XX-A with XX the number of individual
Kastner, Wagner, Hawes, & Ebersole, 2002), MRIs that were used for averaging. The pro-
24 Human Cognitive Neurophysiology 2012, 5 (1)
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
Figure 2: 3-D rendering of the Talairach bounding box with the AC and PC landmarks. The mid-sagittal
plane through AC and PC, the axial plane through AC and PC, and the two coronal planes through AC
and PC, respectively, define twelve compartments used for the piece-wise linear transformation between
individual subject and Talairach coordinates.
posed procedure was designed to accomplish boxes a natural choice as the basis of co-
the following aims: registration.
1) The averaged MRI should clearly show 4) Group-intrinsic head shapes and brain di-
prominent features such as the brain, the skull, mensions should be preserved in the resulting
and the skin layers, equalizing within-group average, making it necessary to spatially nor-
head shape variations. Therefore, individ- malize individual MRIs to the average popula-
ual MRIs need to be spatially normalized be- tion’s brain dimensions before averaging.
fore averaging, so that matching features co-
5) As an alternative to or extension of creat-
localize.
ing an averaged MRI from the individual MRIs
2) Furthermore, each individual MRI should used, it should be possible to spatially nor-
have the same impact on the resulting aver- malize an existing averaged MRI such as the
age, independent of its overall intensity. This ICBM-152 to match the population of inter-
implies that MRI intensities have to be normal- est. The result is a version of the ICBM-152
ized before averaging. that exhibits a head shape and size match-
3) The co-registration of averaged MRIs to ing the population of interest. This population-
the Talairach atlas as well as to averaged MRIs specific ICBM-152-based dataset will also be
of different subject populations and to indi- called an adapted ICBM-152 dataset or ICBM-
vidual MRIs should be straightforward. This 152-A. For some populations (e.g. in pediatric
makes the Talairach landmarks and bounding studies), other existing templates besides the
2012, 5 (1) Kognitive Neurophysiologie des Menschen 25
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
ICBM-152 dataset might be preferable candi- nique, which involved matching all MRIs onto
dates for adaptation. one MRI randomly selected from the popula-
6) In preparation of an EEG or MEG study, tion of interest as an intermediate step. Fur-
the resulting averaged MRI dataset should be thermore, this study did not demonstrate atlas
used to create a population-specific realisti- co-registration nor the derivation of head mod-
cally shaped head model, and used as a ba- els and electrode layouts.
sis for calculating the 10-20 electrode system
positions on the shape of its segmented skin.
7) Finally, creating the averaged MRI should Methods
require little user interaction so that it can eas-
ily be applied for a given population. MRI Acquisition
Existing approaches for creating averaged The subject sample consisted of 62 subjects
MRI datasets are summarized in (Toga & (37 females and 25 males), with an average
Thompson, 2001). Most approaches achieve age of 22.4 years and a standard deviation
this by means of a template and use high- (SD) of 2.1 years. At this age, all subjects
parametric, non-linear transformations (Klein had already attained their adult head shapes
et al., 2009), which allow a mapping of sub- (Friede, 1981). All subjects were right-handed
cortical structures between individual and ethnic Chinese with no history of neurological
averaged MRI, but introduces the problem disorders. Handedness was verified using the
of choosing the right template to match the Edinburgh Inventory (Oldfield, 1971). All sub-
population-of-interest. The specific goals of jects negated when asked for psychiatric dis-
this study in the context of EEG and MEG eases. Written consent of the participants was
analysis gives the mapping of sub-cortical obtained before MRI scanning, with the proto-
structures a lower priority, with the benefit that col approved by the Institutional Ethics and Ra-
a template-free ansatz can be pursued, where diation Safety Committees of National Yang-
image data are normalized onto the average Ming University, Taipei, Taiwan.
of their Talairach bounding boxes.
Whole-head T1-weighted MRI datasets of all
In order to demonstrate the procedure, 62 subjects were acquired at the Laboratory of
individual MRIs of ethnic Chinese subjects Cognitive Neural Science, Yang-Ming Univer-
have been processed and an averaged Chi- sity, Taipei, Taiwan. A magnetization-prepared
nese MRI-62-A dataset as well as an adapted rapid gradient-echo (MP-RAGE) sequence run
ICBM-152-A dataset have been created on a 3T TrioTim scanner (Siemens, Erlan-
Previous studies (Tang et al., 2010; Chee gen, Germany) was used for the acquisition.
et al., 2009; Kochunov et al., 2003) have al- The pixel dimensions and slice thickness were
ready established that significant differences 1 mm each. The matrix size was 224x256, re-
between Chinese and Caucasian head shapes sulting in a field-of-view (FOV) of 224x256 mm.
exist. One previous study also created an The number of slices was 192.
averaged Chinese MRI dataset (Tang et al.,
2010) but used a different co-registration tech-
26 Human Cognitive Neurophysiology 2012, 5 (1)
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
Landmark and Bounding Box intensities were linearly scaled so that the
Determination 99th intensity percentile was the same across
datasets. The 99th percentile was chosen as
MRI data were loaded into the Curry 7 soft- a noise-insensitive measure of the maximum.
ware (Compumedics, Charlotte, NC, USA). In Finally, an averaged 3-D image was computed
Curry, the locations of AC and PC were de- which will be called the MRI-62-A in the re-
termined manually. An additional mid-sagittal mainder of the paper.
landmark (MS) in a more superior slice al- In the same way as described above for
lowed, together with AC and PC, to define the individual MRIs, the ICBM-152 was trans-
the mid-sagittal plane. Based on this in- formed such that its AC-PC distance as well as
formation, the 3-D bounding box containing its Talairach bounding box extents matched the
the brain was gauged, comprising the fol- average values of the subject population, yield-
lowing distance measures: AC-Anterior, PC- ing an ICBM-152-A dataset. Figure 3 shows
Posterior, AC-Superior, AC-Inferior, AC-Left, this procedure in a flowchart.
and AC-Right, in addition to the AC-PC dis-
tance already obtained. The averages of these
Electrode Locations and Head Models
measures were computed and compared to
their equivalents in the ICBM-152 template For the original and the adapted ICBM-152
and the Talairach atlas. A two-tailed z-test was as well as for the MRI-62-A, the locations of
used to assess whether the observed differ- the nasion, left and right pre-auricular point,
ences are significant. and inion landmarks were determined. Based
on these landmarks and the skin surface seg-
Averaged MRI Dataset and Adapted mented from MRI, electrode locations for the
ICBM-152 extended 10-20 system were computed by the
Curry software (Wagner, Fuchs, & Kohlhoff,
Each MRI was then re-sliced according to the 1996). Computations included measuring and
coordinate axes spanned by AC, PC, and the subdividing distances on the outer surface of
mid-sagittal plane, and its twelve sub-volumes the segmented skin, replicating the proce-
defined by AC, PC, and the bounding box di- dure for manual electrode placement (Jasper,
mensions were individually, linearly and con- 1958; Chatrian, 1985). As a result, for these
tiguously transformed. For details on this pro- three datasets, 86 electrode locations were ob-
cess, please refer to the Appendix. The av- tained, identified by their labels. These 86
erage measures obtained in the previous step electrode locations included ten sub-temporal
were used as the dimensions of the target locations, which could not be reliably esti-
bounding box. The outcome was 62 volumet- mated for the ICBM-152 and ICBM-152-A be-
ric images with identical locations of AC and cause of their limited inferior extensions. For
PC landmarks, identical mid-sagittal planes, the remaining 76 electrodes, the average and
and identical bounding boxes enclosing the standard deviation of the distances between
brains. In these images, all brains occu- electrodes of the same label were determined
pied the same coordinate space. Then, MRI across all three datasets.
2012, 5 (1) Kognitive Neurophysiologie des Menschen 27
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
Figure 3: Flowchart for creating the MRI-A and ICBM-152-A datasets.
In a next step, realistically shaped three- Results
compartment boundary element method
(BEM) head models were created using the Chinese vs. Caucasian Brain Dimensions
automatic BEM geometry setup algorithm Table 1 lists averages, standard deviations,
implemented in the Curry software (Wagner, and medians of the AC-PC distances, bound-
Fuchs, Drenckhahn, Wischmann, Köhler, & ing box extents, and bounding box volumes ob-
Theißen, 1997). Triangle side lengths for the tained for the 62 individual MRIs and compares
inner skull, outer skull, and the skin boundary them with their counterparts for the Talairach
were 5 mm, 7 mm, and 8 mm, respectively. atlas and the ICBM-152. Comparing the 62
As a byproduct of this algorithm, triangle Chinese subjects with the Talairach atlas, all
meshes representing the skin and the cortex bounding box extents as well as the width-to-
are obtained. length and height-to-length ratios turn out to
be significantly different; the bounding box vol-
ume and the height-to-width ratio, however, are
not. A comparison with the ICBM-152 dimen-
sions shows significant differences for all but
the mediolateral dimensions and the height-to-
length ratio.
For a trained user, it took about two min-
utes per dataset to define the landmarks and
28 Human Cognitive Neurophysiology 2012, 5 (1)
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
Table 1: Chinese vs. Caucasian Brain Dimensions. Averages, standard deviations (SD), and medians
of the AC-PC distances, bounding box extents, bounding box volumes, and bounding box extent ratios
obtained for the 62 individual MRIs together with their counterparts for the Talairach atlas and the ICBM-
152 dataset. Length is the sum of the anterior, posterior, and AC-PC distances. Width is the sum of the
left and right extents. Height is the sum of the superior and inferior extents. W/L is the width-to-height-
ratio. H/L is the height-to-length-ratio. H/W is the height-to-width-ratio. Probability values p for the
Null hypothesis obtained by means of a two-tailed z-test are shown for the Talairach and the ICBM-152
measures. Small values denote significant differences between the respective dataset and the group of 62
individual MRIs.
AnteriorPost. AC- Sup. Inf. Left Right Length Height Width Volume W/L H/L H/W
[mm] [mm] PC [mm] [mm] [mm] [mm] [mm] [mm] [mm] [l] ratio ratio ratio
[mm]
Average 67.7 70.2 24.4 75.0 45.0 70.4 70.5 162.3 120.0 140.9 2.75 0.870 0.741 0.853
SD 2.5 4.3 1.0 2.7 2.2 2.6 2.6 6.7 4.2 4.9 0.23 0.044 0.029 0.033
Median 67.6 70.5 24.5 74.2 45.2 70.5 70.5 162.5 119.3 141.0 2.73 0.865 0.738 0.854
Talairach 70.0 79.0 23.0 74.0 42.0 68.0 68.0 172.0 116.0 136.0 2.71 0.791 0.674 0.853
p≤ 10−5 10−5 10−5 0.005 10−5 10−5 10−5 10−5 10−5 10−5 0.233 10−5 10−5 0.926
ICBM 71.0 78.0 28.0 83.0 47.0 70.0 70.0 177.0 130.0 140.0 3.22 0.791 0.734 0.929
p≤ 10−5 10−5 10−5 10−5 10−5 0.215 0.132 10−5 10−5 0.141 10−5 10−5 0.101 10−5
2012, 5 (1) Kognitive Neurophysiologie des Menschen 29
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
bounding box dimensions required. non-individual MRIs they were created from.
Averaged MRI Dataset and Adapted
ICBM-152 Dataset
Discussion and Conclusion
Figure 4 shows the MRI-62-A dataset based
on 62 Chinese subjects and the ICBM-152- The proposed procedure meets the aims pre-
A. Due to the normalization of each individ- sented in the introduction: As a demonstra-
ual dataset to the Talairach bounding box, the tion of the proposed procedure, an averaged
MRI-A is least blurry at the locations of AC and MRI dataset representing a normal, adult Chi-
PC. The overall head shape of the ICBM-152-A nese population called the MRI-62-A dataset
is the same as for the MRI-62-A. For the MRI- has been created. The MRI-62-A dataset
62-A, the skull areas around the brain are not shows prominent features such as the brain,
everywhere as sharply delineated as for the the skull, and the skin layers. Group-intrinsic
ICBM-152-A. head shapes and brain dimensions have been
preserved. Its co-registration to the Talairach
Electrode Locations and Head Models atlas as well as to other MRIs can be per-
formed using the same Talairach-based ap-
A rendering of the three sets of extended proach as used for averaging. A population-
10-20 system electrodes obtained for the specific ICBM-152-based dataset called the
MRI-62-A, ICBM-152, and ICBM-152-A ICBM-152-A has been created. It exhibits a
datasets is shown in Figure 5. head shape and brain size matching the popu-
Table 2 shows the average distances and lation of interest. On the basis of the MRI-62-
their standard deviations together with the A and the ICBM-152-A, realistic head models
median distances between electrodes of the and standard electrode layout shave been cre-
same label for the three pairs of datasets. ated.
Electrode location differences are largest be- With about two minutes of user interac-
tween the MRI-62-A and the ICBM-152. They tion per individual MRI (all other calculations
are smallest between the MRI-62-A and the were automated), the process of creating a
ICBM-152-A, with a mean displacement of population-adapted averaged MRI is straight-
less than 5 mm. forward.
The realistic BEM head model represent- The size differences between Chinese and
ing the MRI-62-A dataset consists of 12,132 Caucasian brains are significant, with Chinese
triangles connecting 6,072 nodes. The ICBM- brains being e.g. comparatively shorter than
152-A BEM contains 12,264 triangles and both the Talairach atlas brain and the ICBM-
6,138 nodes. Its inferior extension is smaller 152. These findings agree with the ones re-
than for the MRI-62-A model. Figure 6 shows ported in (Tang et al., 2010), although it should
both BEMs together with cortical triangle be mentioned, that due to the brain-stripping
meshes. These cortical triangle meshes do approach employed in that study, measures
not show individual gyri and sulci, due to the are not directly comparable.
30 Human Cognitive Neurophysiology 2012, 5 (1)
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
Figure 4: Upper row: MRI-62-A dataset based on 62 Chinese subjects. Lower row: ICBM-152-A dataset
with the average Chinese subject’s brain dimensions.
Table 2: Average distances and their standard deviations together with the median distances between elec-
trodes of the same label for pairs of datasets. Electrode locations were obtained according to the extended
10-20 electrode system procedures.
MRI-62-A vs. MRI-62-A vs. ICBM-152-A vs.
ICBM-152m[ m] ICBM-152-Am[ m] ICBM-152 [mm]
Average 11.0 4.7 7.6
SD 3.7 1.8 3.0
Median 10.8 4.8 7.6
2012, 5 (1) Kognitive Neurophysiologie des Menschen 31
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
Figure 5: Extended 10-20 system electrodes for the ICBM-152 (light gray), the ICBM-152-A (dark gray),
and the MRI-62-A (black), together with the skin surface of MRI-62-A.
32 Human Cognitive Neurophysiology 2012, 5 (1)
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
(a)
(b)
Figure 6: Realistically shaped BEM head models enclosing the cortical surface for a) the MRI-62-A
dataset and b) the ICBM-152-A dataset.
2012, 5 (1) Kognitive Neurophysiologie des Menschen 33
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
In a population-specific EEG or MEG study, mendation can be spelled out.
finding significantly different brain dimensions Of course, the quality of individual MRIs for
between the population-of-interest and an ex- a given population may vary, so that using the
isting, candidate MRI template should motivate ICBM-152-A may be a welcome alternative if a
the creation and use of an MRI-A or an ICBM- low number of individual MRIs are available or
152-A dataset instead of just using the tem- if these are of low quality.
plate.
Furthermore, it should not be forgotten that
An important practical question is, which the ICBM-152 has by now become part of the
of the two adapted MRIs, the MRI-A or the community’s viewing habits, so that presenting
ICBM-152-A, is better suited for being used in one’s results in that context may make them
a given study: easier to perceive. This is of course not true, if
Both adapted datasets can be linked to ad- the subject population is pediatric. In this case,
ditional atlas data because their Talairach pa- either an existing pediatric template (Sanchez,
rameters are known. Richards, & Almli 2011) may be adapted us-
Due to the bounding box-based head shape ing a process analogous to the one described
normalization before averaging, the quality of above for the creation of the ICBM-152-A, or
the MRI-A dataset is not uniform: it is highest the MRI-A should be used.
around the AC and PC landmarks and where Whichever dataset is chosen for a particular
the brain touches the planes of the bounding study, the possibility to use electrode locations
box, but and lower in other areas, such as the and a head model that are fit for the population
dorsolateral prefrontal cortex (Brodmann area of interest, to overlay source results onto an
9). This is not the case for the ICBM-152-A, anatomical image with matching head shape,
because a different, template-based approach and the possibility to use adapted atlas data
was used for normalizing individual MRIs in the to constrain source analysis and report results
course of the ICBM-152 creation. recommend using an adapted averaged MRI
Due to the larger field-of-view of the indi- for studies involving non-Caucasian or pedi-
vidual MRIs used for averaging in this study, atric populations.
sub-temporal electrode locations according to While it has been shown that brain exten-
the extended 10-20 system can be computed sions and standard electrode locations vary
for the MRI-62-A but not for the ICBM-152-A. significantly between the ICBM-152 and the
For the same reason, the MRI-62-A BEM has population-specific MRIs, this is only a hint
a wider inferior coverage, which commends that differences in source localization are also
the use of the MRI-62-A for studies involv- to be expected. A follow-up study will exam-
ing sub-temporal electrodes. For the other 76 ine the effect of the different MRIs and their
electrode locations, a mean difference of less derived head models and electrode locations
than 5 mm between both adapted datasets is onto source localizations.
still lower than the electrode location errors
brought about by using caps with labeled elec-
trodes, so that in such a setup no clear recom-
34 Human Cognitive Neurophysiology 2012, 5 (1)
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
Acknowledgments References
M. Wagner thanks C.W. Ponton for the initial Chatrian, G.E. (1985). Ten percent electrode
impetus to work on MRI averaging. This work system for topographic studies of sponta-
was supported in part by the National Science neous and evoked EEG activity. Am J Elec-
Foundation of Taiwan under Grant 98-2517-S- troencephalogr Technol, 25, 83-92.
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2012, 5 (1) Kognitive Neurophysiologie des Menschen 37
M. Wagner & W.-J. Kuo – Population-Adapted Averaged Head Templates
Appendix If t denotes Talairach space, the bounding
box dimensions (see Table I) are tAC−A =
Transformation from MRI Space to Template
70mm, tPC−P = 79mm, tAC−PC = 23mm,
Space
tS = 74mm, tI = 42mm, tL = 68mm, and
The co-registration of a specific image tR = 68mm.
“dataset” (identified by the letter d) into a Analogously, dAC−A, dPC−P , dAC−PC , dS ,
common “template” space (identified by the dI , dL, and dR describe the bounding box
letter t) is described below. In the scope of this measures in dataset space. The locations of
paper, the interpretation of what the “dataset” AC and PC in dataset space are dAC and dPC .
and “template” exactly are differs, depending Additionally, the location of a superior mid-
on which part of the process we are looking sagittal location, dMS serves to unambiguously
at: When averaging individual MRIs to create identify the orientation of the z axis.
an MRI-A dataset, d denotes the individual The transformation from dataset space into
MRIs while t refers to the average space template space consists of three steps: trans-
based on measures obtained for all individual lation, rotation, and scaling. In a first step, a
MRIs. When creating an ICBM-152-A dataset, translation maps dAC , onto tAC (the origin).
d refers to the ICBM-152 dataset while, as Next, a rotation maps dPC onto the negative
above, t refers to the average space based y axis and dMS onto the y-z plane. The scal-
on all individual MRIs. When transforming the ing step ensures that the bounding box dimen-
MRI-A or the ICBM-152-A to Talairach atlas sions co-localize:
space (or vice versa), d refers to the former, 
while t represents the latter. x tL for x ≤ 0
x→ dL
The locations of AC and PC in template x tRd for x > 0R
space are tAC and tPC . tAC is always in the  (y + dAC−PC)×
origin, and tPC is always on the negative y  for y ≤ −dAC−PCtPC−P
axis, so that − t→ AC−PCy
    
dPC−P
y tAC−PCd for − d− AC−PC < y ≤ 0AC PC
tAC−A
tAC =  0  0 y d for y > 0AC−A0 and  tPC =  −tAC−PC  z tId for z ≤ 00 0 z → Iz tSd for z > 0S
where tAC−PC is the AC-PC distance. The This scaling step ensures a contiguous map-
positive x axis points right, y points anterior, ping without any jumps at the compartment
and z points up. The bounding box dimen- boundaries.
sions (see Figure 2) are given by the AC-
Anterior distance tAC−A, the PC-Posterior dis-
tance tPC−P , the already mentioned AC-PC
distance tAC−PC , the AC-Superior distance tS ,
the AC-Inferior distance tI , the AC-Left dis-
tance tL, and the AC-Right distance tR.
38 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
Abstract
M. Ruchsow (Göppingen) — Personale Identität aus Sicht der Neurowissenschaften und der ana-
lytischen Philosophie
The problem of personal identity is discussed very controversially in analytical philosophy and contempo-
rary neuroscience. Descartes’ approach was a dualism of substances (res cogitans and res extensa). This
solution was rejected by Locke and other empiricists, because substances can never be the object of pos-
sible experience. Locke proposed (autobiographic) memory as warrant of (diachronic) personal identity.
Alternatively, the criterion of bodily continuity was suggested, with body, brain or “relevant parts” of the
brain facilitating diachronic identity. As Parfit showed, both naturalistic (neuroscientific) criteria (auto-
biographic memory and “enough of the brain”) are contradictory. Taylor’s concept of narrative identity
might be a continuative approach.
Keywords: Personal Identity, Introspection, Narrative Self
Personale Identität aus Sicht individuelle Freiheit dadurch errungen, dass
der Neurowissenschaften wir uns von einem älteren Moralhorizont gelöst
haben. Damit einhergehend gerieten auch die
und der analytischen alten Ordnungsgefüge in Misskredit und die
Philosophie Vorstellung, dass die „hierarchical order in
the universe was reflected in the hierarchies
M. Ruchsow, Fachkrankenhaus of human society“. Gleichzeitig verliehen die
Christophsbad, Faurndauer Str. 6-28, 73035 alten Ordnungen aber auch „meaning to the
Göppingen world and to the activities of social life“ (Taylor,
martin.ruchsow@christophsbad.de 1991, S. 3). Die neuzeitliche Entwicklung führt
also zu einem Zuwachs an individueller Frei-
heit, andererseits aber auch zu einem Verlust
Einleitung
an Orientierung bzw. sozialer Freiheit (d.h.
Mit Beginn der Neuzeit geht der Glaube an Sittlichkeit im Sinne Hegels). Das Konzept der
einen sinnvollen, identitätsstiftenden Kos- sozialen Freiheit bzw. Sittlichkeit greift den
mos zunehmend verloren. Der kanadische antiken Polisgedanken auf, demzufolge die
Philosoph Charles Taylor sieht diese Entwick- Bürger „had such a deep subjective attach-
lung durchaus ambivalent und spricht, Max ment to their polis that their social membership
Webers Diktum von der „Entzauberung der could be said to constitute a central part of
Welt“ aufnehmend, von einem „Unbehagen an their own identities“ (Neuhouser, 2000, S. 34).
der Moderne“. Aus Taylors Sicht wurde mehr Das Problem der personalen Identität ist
2012, 5 (1) Kognitive Neurophysiologie des Menschen 39
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
also eine neuzeitliche Fragestellung, die den Von numerischer oder logischer Identität
geschilderten historischen Prozess zur Vo- sprechen wir, wenn folgende Kriterien erfüllt
raussetzung hat. Typische Vertreter dieser sind:
neuzeitlichen Konstellation sind Descartes a.) Symmetrie (x = y →y = x),
und Locke, für die Personen „desengagierte“ b.) Transitivität (x = y ∧ y = z →x = z) und
neutrale Beobachter einer weitgehend mech- c.) Reflexivität (x = x) (vgl. Gillitzer, 2001, S.
anistisch zu erklärenden äußeren Wirklichkeit 24)
sind (vgl. Taylor, 1989, S. 143 ff.).
Zwei Dinge sind numerisch identisch (also
Nach einer kurzen Präzisierung, was in der
der Zahl nach ein einziges Ding), wenn sie hin-
vorliegenden Arbeit unter „Identität“ zu verste-
sichtlich aller ihrer Eigenschaften gleich sind.
hen ist, wird zunächst Descartes’ Personbe-
Demgegenüber bezeichnen wir zwei ver-
griff als substantielle Einheit von res cogitans
schiedene Gegenstände als qualitativ iden-
und res extensa vorgestellt. Die Ablehnung
tisch, wenn sie sich lediglich ähnlich, also
von Substanzen als möglichen Gegenständen
nur in einer bestimmten Eigenschaft (oder
von Erfahrung durch den Empiristen Locke
mehreren) gleich sind. Numerische Identität
führt u.a. zum Problem der diachronen Iden-
ist somit ein Grenzfall qualitativer Identität
tität, das er durch das Erinnerungskriterium
(Gleichheit hinsichtlich aller Eigenschaften vs.
zu lösen versucht. Im weiteren Verlauf wird
Gleichheit hinsichtlich einer/mehrerer Eigen-
sich zeigen, dass sowohl das Kriterium der
schaften; Tugendhat & Wolf, 1983, S. 168
psychischen Kontinuität (Erinnerung) als auch
f.).
das der physischen Kontinuität (des Kör-
pers oder des Gehirns) widersprüchlich ist. Hinsichtlich 2.) bleibt festzuhalten, dass
Als ein möglicherweise weiterführender Lö- der Begriff der qualitativen Identität auch in
sungsansatz wird dann Taylors Konzept der einer erweiterten Bedeutung gebraucht wird.
narrativen Identität erläutert. Er bezieht sich dann auf den autonomen
Lebensentwurf von Personen und die damit
einhergehenden existentiellen Fragen: „Wer
1. Identitätsbegriffe bin ich?“ und: „Wer will ich sein?“ Durch
ihre Antworten orientieren sich Personen gle-
Der Begriff der Person ist historisch wie sys- ichzeitig in einem „moralischen Raum“ bzw.
tematisch mit den beiden eng zusammenhän- verorten sich auf einer „moralischen Land-
genden Problemkreisen der karte“ (Taylor, 1989, S. 25 ff.).
In der vorliegenden Arbeit wird der Termi-
1. Identität von Personen und der nus „numerische Identität“ verwendet, wenn
2. Autonomie von Personen verbunden (vgl. die Zahl der zugrundeliegenden Entitäten rel-
Krebs, Kambartel & Jantschek, 1995, S. evant ist, also die Frage, ob von einer oder
89 ff.). mehreren Personen geredet wird. Der Begriff
der „qualitativen Identität“ wird ausschließlich
Hinsichtlich 1.) ist zu unterscheiden zwischen in der erweiterten Bedeutung verwendet, also
numerischer und qualitativer Identität. wenn die qualitativen Aspekte von Personalität
40 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
und insbesondere die moralische Dimension 3. auf die Vereinigung von eigenem Körper
von Lebensentwürfen im Vordergrund stehen und Geist bezieht, d.h. die Person (Kem-
(vgl. Ruchsow & Hermle, 2007). merling, 2005, S. 123).
Es wird außerdem zwischen dem Problem
Den drei Ichbegriffen sind dementsprechend
der
drei Weisen der Erkenntnis zugeordnet:
I synchronen und dem der
1. Die (eigene) Seele („das Ich“) kann nur
II diachronen Identität unterschieden, durch den Intellekt erkannt werden. Der
reine Intellekt wird nach Descartes durch
also der Identität einer Person zu einem bes- metaphysische Gedanken trainiert, die
timmten Zeitpunkt und der Identität im Zeitver- uns mit dem Begriff des Geistes vertraut
lauf. machen sollen.
Im Rahmen seines Substanzendualismus
war für Descartes die Lösung von I.) beson- 2. Bei der Erkenntnis des (eigenen) Kör-
ders vordringlich, während II.) aufgrund der pers (d.h. Ausdehnung, Gestalt und
Unveränderlichkeit von Substanzen bzw. der Bewegung) muss der Intellekt von der
Unsterblichkeit der Seele(nsubstanz) unprob- (bildlichen) Vorstellungskraft unterstützt
lematisch war. Für Locke ergab sich nach werden. Die Vorstellungskraft wird vor
Preisgabe des Substanzbegriffs genau die allem durch mathematische Studien
umgekehrte Problemkonstellation: II.) war geschult; sie gewöhnen uns daran, deut-
deutlich schwieriger zu lösen als I.). liche und klare Begriffe von Körpern zu
bilden.
2. Descartes 3. Die Person, d.h. die Vereinigung von
Körper und Geist, wird weder durch den
2.1.Descartes’ Personbegriff reinen Intellekt, noch durch den von der
Descartes gebraucht den Begriff der Per- Vorstellungskraft unterstützten Intellekt
son eher selten (Thiel, 2011, S. 36). Wenn adäquat erfasst. Nur „das gewöhnliche
Descartes von „persona“ bzw. „personne“ Leben und das alltägliche Gespräch
spricht, versteht er darunter „die Vereinigung lehren uns, die Vereinigung von Körper
von (Menschen-) Körper und (Menschen- und Geist zu begreifen, und zu diesem
)Geist“. Kemmerling unterscheidet in diesem Zwecke solle man sich tunlichst jedweder
Zusammenhang drei Ichbegriffe: metaphysischen und mathematischen
Betätigung enthalten (Kemmerling, 2005,
1. Den Ausdruck „das Ich“, also die sub- S. 124).“
stantivierte „ich“-Redeweise, verwendet
An verschiedenen Stellen betont Descartes
Descartes, um sich auf die eigene Seele
diese enge Verbindung von Körper und
bzw. den eigenen Geist zu beziehen,
Geist, die seinen Personbegriff ausmacht.
während „ich“ sich
So schreibt er in der Sechsten Meditation,
2. sowohl auf den eigenen Körper, als auch dass sich seine Seele nicht einfach in seinem
2012, 5 (1) Kognitive Neurophysiologie des Menschen 41
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
Körper befinde wie ein Schiffer in seinem 2. Eine körperlich-geistige Stufe.
Schiff, sondern aufs innigste mit ihm vereint
sei und ihn gleichsam durchdringe (Descartes, 3. Eine rein geistige Stufe, die genau dann
1641/2009, S. 88). Wiederholt weist er darauf vorliegt, wenn ein Urteil über das äußere,
hin, dass Körper und Geist eine „substantielle auf den Körper einwirkende Objekt
Einheit“ bzw. „essentielle Einheit“ bilden (Per- gebildet wird.
ler, 2006, S. 213). Geist und Körper sind „in
gewissem Sinn“ unvollständige Substanzen. Im Kontext von Descartes’ Personbegriff ist die
Zu vollständigen (funktionsfähigen) werden zweite Stufe von besonderer Bedeutung, „die
sie erst in der essentiellen Einheit. Descartes nur aufgrund der essentiellen Einheit von Kör-
unterscheidet dementsprechend zwischen per und Geist möglich ist“ (Perler, 2006, S.
„ens per se“ und „ens per accidens“. Wenn 214).
zwei Substanzen zufällig miteinander verbun-
den sind („ens per accidens“) „und alle ihre 2.2. Die aristotelisch-scholastische
Funktionen auch unabhängig voneinander Tradition
ausüben können, bilden sie zusammen eine
akzidentelle Einheit - ein bloßes Konglom- Descartes’ Personbegriff muss vor dem Hin-
erat, das nicht mehr ist als die Summe seiner tergrund der aristotelisch-scholastischen Tra-
beiden Bestandteile. Wenn hingegen zwei dition gesehen werden, der zufolge „eine
Substanzen derart miteinander verbunden Person eine natürliche Substanz ist, die aus
sind, dass sie nicht alle ihre Funktionen unab- Form und Materie besteht: Die Seele ist die
hängig voneinander ausüben können, bilden Form, der Körper die Materie“ (Perler 2006, S.
sie zusammen eine essentielle Einheit - et- 210). Im Rahmen seines hylemorphistischen
was Komplexes, was mehr ist als die Summe Ansatzes betrachtete Aristoteles die Seele als
seiner Bestandteile. Genau dies ist bei der Lebensprinzip, das ein Stück Materie erst zu
Verbindung von Körper und Geist der Fall“ einem funktionierenden, lebendigen Körper
(Perler, 2006, S. 213). macht. Dieser Ansatz hat den Vorteil, dass die
Die enge Verbindung von res cogitans und Person von vornherein als Einheit (im Sinne
res extensa in der Person zeigt sich insbeson- synchroner Identität) aufgefasst werden kann,
dere im Bereich der Sinneswahrnehmung und jedoch den Nachteil - insbesondere für die
der Schmerzempfindung, die weder der Geist christlichen Kommentatoren des Mittelalters -
noch der Körper allein ausüben können. Bei dass die Seele nicht unsterblich ist, sondern
der Analyse der Sinneswahrnehmung unter- mit dem Körper untergeht.
scheidet Descartes wiederum „drei Grade“ Die spätmittelalterlichen Aristoteliker wie
oder Stufen voneinander: z.B. Thomas von Aquin versuchten dieser
Konsequenz u.a. durch eine differenzierte
1. Eine rein körperliche Stufe, die sich bei Theorie des Intellekts bzw. der Seele zu ent-
Tieren und Menschen findet, und durch di- gehen. Demnach bildeten nur die „niederen“
rekte Einwirkung eines Objektes auf den Teile der Seele das Lebensprinzip und gehen
Körper eine Nervenreizung verursacht. mit dem Tod des individuellen menschlichen
42 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
Körpers zugrunde. Der Intellekt als der „er- 2. sein Substanzbegriff die Unsterblichkeit
habene“ Teil der menschlichen Seele überlebt der Seele garantieren, da sich Sub-
den Tod und geht nicht mit dem Körper unter. stanzen nach klassischem Verständnis
Durch eine solche Erklärung wurde versucht, nur hinsichtlich ihrer akzidentellen Eigen-
die Einheit der Person und die Unsterblichkeit schaften ändern können.
der Seele zusammen zu denken (vgl. Perler, Für Descartes ist die Seele zudem - im Gegen-
2006, S. 211). satz zum Körper - eine besondere („reine“)
Eine besonders einflussreiche Kritik an Substanz, da sie unteilbar sei (d.h. unzer-
der aristotelisch-scholastischen Lehre for- störbar = unsterblich). So betont er „dass
mulierte Der Renaissancephilosoph Pietro wir einen Körper nur als teilbar, einen Geist
Pomponazzi in seiner Schrift „De Immortal- dagegen nur als unteilbar einsehen können:
itate Animae“ („Über die Unsterblichkeit der Denn die Hälfte eines Geistes können wir nicht
Seele“) aus dem Jahr 1516. Er zeigt dort, dass begreifen, wie wir es doch bei jedem beliebig
die Aristoteliker, insbesondere Thomas von kleinen Körper können; so dass wir ihre Na-
Aquin, die Seele einerseits als sehr eng mit turen nicht nur als verschieden, sondern sogar
dem Körper verbunden dachten, andererseits als gewissermaßen entgegengesetzt erken-
aber als eine Entität, die auch unabhängig nen“ (Descartes, 1641/2009, S. 14). Aus der
vom Körper existieren kann. Die Seele ist also Teilbarkeit (= Sterblichkeit) des Körpers folgt
einmal etwas, wodurch etwas lebendig ist (ein also keineswegs die Vernichtung des Geistes
„quo est“) ein andermal etwas, was an sich (= Sterblichkeit der Seele), wie Descartes
existiert (ein „quod est“). Nach Pomponazzi einige Zeilen später deutlich herausstellt. Je-
lässt sich dieser Widerspruch im Rahmen doch muss er den endgültigen Beweis der
einer aristotelisch-scholastischen Theorie der Unsterblichkeit der Seele - zumindest im
Person nicht auflösen. Rahmen der „Meditationen“ - eingestanden-
Unklar ist, ob Descartes Pompanazzis Text ermaßen schuldig bleiben. Darüber hinaus
gelesen hat, auf jeden Fall war er mit der daran ist das Argument für die Unteilbarkeit (= Un-
anschließenden Kontroverse vertraut (vgl. sterblichkeit) der Seele nur dann stichhaltig,
Perler, 2006, S. 212). Descartes versucht, das wenn Descartes entweder zeigen kann, dass
von Pompanazzi formulierte Problem durch
Annahme eines Substanzendualismus (von 1. die Zerstörung der Seele durch Teilung
res cogitans und res extensa) zu lösen. Auf die einzige Art ihres Zugrundegehens ist
diese Weise versucht er die enge Einheit von oder
Seele und Körper mit der Unsterblichkeit der 2. alle anderen Arten des Zugrundegehens
Seele zusammen zu denken. Dabei soll die menschliche Seele nicht betreffen
(Perler, 2006, S. 179 f.).
1. sein Personbegriff, verstanden als sub-
stantielle Einheit von Körper (res extensa)
2.3. Cartesianischer Dualismus
und Seele (res cogitans), den hylemor-
phistischen Ansatz der aristotelisch- Descartes’ dualistische Substanzenlehre ist
scholastischen Tradition ersetzen. eine Voraussetzung seines Personbegriffs.
2012, 5 (1) Kognitive Neurophysiologie des Menschen 43
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
Baker und Morris unterscheiden zwischen Legendenbildung sind somit die „doctrines of
Descartes’ Dualismus („Descartes’ Dualism“) ’the epistemological transparency of thought’
und dem von ihnen sogenannten Cartesian- [...] and of ’Cartesian Privacy’“ von entschei-
ischen Dualismus („Cartesian Dualism“), der dender Bedeutung (Baker und Morris, 2002,
im wesentlichen auf einer Legendenbildung S. 19), wobei die Doktrin der epistemologis-
(„Cartesian Legend“) im Bereich der Analytis- chen Transparenz besagt, dass „introspection
chen Philosophie beruht (Baker und Morris, is essentially and universally infallible“ (Ryle,
2002). Zentraler Bestandteil des Cartesian- 1949, S. 14). „If I think, hope, remember, will,
ischen Dualismus ist die Fähigkeit zur Intro- regret, hear a noise, or feel a pain, I must, ipso
spektion („Cartesian Introspection“), die Baker facto, know that I do so“ (Ryle, 1949, S. 158).
und Morris folgendermaßen charakterisieren: Die Doktrin der Cartesianischen Privatheit
„Physical objects are public and observable, führt demgegenüber nicht nur zur bere-
though fallibly, via the senses; mental ob- its beschriebenen Asymmetrie von erster-
jects are private and (quasi-) observable via und dritter Person, sondern ermöglicht auch
the infallible faculty of introspection“ (Baker einen direkten, unmittelbaren bzw. nicht-
und Morris, 2002, S. 11). Auch die scharfe inferentiellen Zugang zu meinen inneren
Kontrastierung von „physical objects“ und Zuständen („by acquaintance“; s. unten).
„mental objects“ gehört zur Cartesianischen So habe ich z.B. (aus der Ersten-Person-
Legendenbildung: „There are two worlds, the Perspektive) unmittelbaren Zugang zu meinen
one populated by physical objects, the other Schmerzen, ohne das aus meinem Verhalten
by mental objects.“ Physikalische Objekte erst irgendwie erschließen zu müssen.
können rein mechanistisch erklärt werden
(„physical objects are essentially (bits of) 2.4. Erkenntnistheorie
clockwork“), während mentale „Gegenstände“
als Bewusstseinszustände aufzufassen sind Descartes’ Überlegungen zum Personbegriff
(„mental objects are essentially (states of) führten uns zu seinem substanzdualistischen
consciousness“; Baker und Morris, 2002, S. Ansatz, der wiederum aus seinen erkenntnis-
11). Diese „Two-Worlds View“ führt dann zum theoretischen Überlegungen resultierte. In-
Problem der Interaktion von physikalischen sofern lässt es sich auch bei Abhandlungen
Gegenständen (wie z.B. dem eigenen Körper) über Descartes’ Sicht der Person kaum ver-
und Mentalzuständen, bzw. zur Asymmetrie meiden, auf seinen epistemologischen Ansatz
von Erster- und Dritter-Person-Perspektive. näher einzugehen.
So macht es zum Beispiel Sinn zu sagen Descartes’ Erkenntnistheorie ist im
„Ich spüre meine Schmerzen“, wohingegen wesentlichen motiviert durch die Suche nach
der Satz „Ich spüre seine Schmerzen“ sinn- einem sicheren und unbezweifelbaren Funda-
los ist. Meine Mentalzustände sind privat, ment des Wissens angesichts der Möglichkeit
während mir die der anderen Menschen nur eines systematischen Skeptizismus. Er be-
indirekt zugänglich sind (z.B. über ihr Ver- ginnt mit der alltäglichen Erfahrung, dass uns
halten). Im Rahmen der Cartesianischen unsere Sinne täuschen und dementsprechend
die meisten unserer Überzeugungen falsch
44 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
sein können. Es ist gar nicht notwendig, „zu sehe, urteile, dass der Erdboden existiert, so
zeigen, dass meine Meinungen allesamt falsch ist daraus sicherlich noch viel mehr abzuleiten,
sind, [...]; sondern weil schon allein die Ver- dass mein Geist existiert: Es ist nämlich vielle-
nunft dazu rät, dass dem nicht völlig Sicheren icht möglich, dass ich urteile, den Boden zu
und Unzweifelhaften die Zustimmung nicht berühren, obwohl gar kein Erdboden existiert,
weniger gründlich entzogen werden muss als nicht jedoch, dass ich dieses Urteil fälle, und
dem offenbar Falschen, wird es schon ausre- mein Geist, der dieses Urteil fällt, nicht sei [...]“
ichen, alles zurückzuweisen, worin ich auch (Descartes, 1644/2005, S. 19 ff.).
nur irgendeinen Grund zum Zweifeln antreffe“ Diese Priorisierung introspektiven Wissens
(Descartes, 1641/2009, S. 20). führte dazu, Descartes’ erkenntnistheoretis-
In einem zweiten Schritt radikalisiert che Position als
Descartes die Möglichkeit des Zweifels, indem
• fundamentalisch und
er feststellt, „dass der Wachzustand niemals
aufgrund sicherer Anzeichen vom Traum • internalistisch zu charakterisieren.
unterschieden werden kann“ (Descartes,
1641/2009, S. 21). Descartes’ Fundamentalismus („foundational-
ism“) zeigt sich vor allem in seiner Auffassung,
Als dritten Zweifelsgrund nennt Descartes dass das mittels Introspektion gewonnene
die Möglichkeit, dass mich Gott bzw. ein Wissen unmittelbarer, sicherer und zuverläs-
böser Dämon täuscht, so dass ich mich frage, siger ist, als das mittels Sinneswahrnehmung,
ob „es überhaupt keine Erde, keinen Himmel, was impliziert, dass ersteres als das Funda-
kein ausgedehntes Ding, keine Gestalt, keine ment für letzteres aufzufassen ist: Descartes
Größe, keinen Ort gibt - und all dies mir trotz- „sees self-knowledge as providing a founda-
dem genau so wie jetzt zu existieren scheint?“ tion for the thinker’s general body of knowl-
(Descartes, 1641/2009, S. 22). edge“ (Gertler, 2011, S. 33).
Bekanntermaßen findet Descartes’ system- Der (epistemologische) Internalismus lässt
atischer Zweifel zu Beginn der Zweiten Med- sich folgendermaßen charakterisieren:
itation im Cogito, d.h. in der Selbstgewis-
sheit des Ichs sein Ende, indem „festgestellt • „Epistemic internalists (generally) accept,
werden muss, dass dieser Grundsatz Ich bin, and externalists deny, that knowledge re-
ich existiere, sooft er von mir ausgesprochen quires that one has accessible reasons for
oder durch den Geist begriffen wird, notwendig one’s belief, whereas externalism rejects
wahr ist“ (Descartes, 1641/2009, S. 28). Aus this access requirement.“
dem Cogito Argument leitet Descartes eine • „[...] knowledge must be supported by
Hierarchisierung des Wissens ab. Das Wis- reasons that are within the thinker’s mind“
sen über unsere Mentalzustände (mittels Intro- (Gertler, 2011, S. 31 f.).
spektion) ist gewisser und grundlegender als
das Wissen über äußere Gegenstände (mit- Legt man die klassische Wissensdefinition
tels Sinneswahrnehmung): „Wenn ich etwa Platons als wahre, gerechtfertigte Meinung
aufgrund dessen, dass ich ihn berühre oder (vgl. Platon, Theätet, 201d-206b) zugrunde,
2012, 5 (1) Kognitive Neurophysiologie des Menschen 45
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
dann unterscheiden sich (epistemologische) wird wiederum durch A selbst gerechtfer-
Internalisten und Externalisten primär hin- tigt.
sichtlich des Rechtfertigungsbegriffs; der
3. Abbruch der inferenziellen Begründun-
Internalist findet die Rechtfertigungsgründe
gen: B, unser Grund für A, wird nicht
für seine Wissensansprüche ausschließlich
weiter gerechtfertigt, sondern (willkürlich)
„im Kopf“, während dies für den Externalisten
als evident, intuitiv einleuchtend, basal,
nicht gilt. Da Descartes beide internalistischen
etc. deklariert.
Kriterien erfüllt, wird er von vielen als „the arch
internalist“ (z.B. Gertler, 2011, S. 32), aber Es ist intuitiv einleuchtend, dass Descartes’ in-
auch als ein paradigmatischer Vertreter eines ternalistischer Fundamentalismus Möglichkeit
„klassischen“ Fundamentalismus gesehen. 3 favorisiert. Descartes’ Idee, dass Perso-
Als „klassisch“ wird ein Fundamentalismus nen mittels Introspektion einen privilegierten
bezeichnet, wenn er postuliert, dass Zugang zu ihren Mentalzuständen haben und
mit diesen unmittelbar (d.h. nicht-inferentiell)
• „das Fundament aller Rechtfertigung [von bekannt sind (im Sinne von „acquaintance“),
Wissensansprüchen; Ergänzung: M.R] ist nicht nur von philosophiehistorischem Inter-
aus unfehlbaren und unanfechtbaren esse. Auch in den gegenwärtigen Diskussio-
Überzeugungen besteht“, nen ist Descartes’ Grundidee, den Personbe-
• wobei „diese basalen Überzeugungen so griff mit der Fundierung von Erkenntnistheorie
beschaffen sind, dass sie selbst einen zu verbinden, von großer Relevanz und wird
Grund für die Einsicht in ihre Wahrheit kontrovers diskutiert.
liefern“ (Grundmann, 2008, S. 284).
2.5. Moderne Versionen des
Internalismus und Fundamentalismus sind internalistsischen Fundamentalismus
Möglichkeiten, einem grundsätzlichen erken-
Viele Philosophen des „Wiener Kreises“ und
ntnistheoretischen Trilemma zu entgehen, das
aus der Frühphase der analytischen Philoso-
in der Antike als Agrippas Trilemma, und in der
phie vertraten Versionen des internalistischen
gegenwärtigen Diskussion als Münchhausen-
Fundamentalismus. So war Russell der Auf-
Trilemma bekannt ist (Albert, 1991, S. 15).
fassung - ähnlich wie Descartes (vgl. das
Möchte ich z.B. Überzeugung A rechtfertigen,
Zitat aus den „Prinzipien“, siehe oben, Ab-
kann ich das mit Hilfe einer weiteren Überzeu-
schnitt 2.4) - dass zwar an der Existenz der
gung B tun, wenn sich A aus B inferenziell
Gegenstände der Außenwelt gezweifelt wer-
erschließen lässt. Wodurch wird jedoch B
den kann, nicht aber an der Realität unserer
gerechtfertigt? Es gibt drei Möglichkeiten, die
Sinneswahrnehmungen: „We have seen that it
alle inakzeptabel sind:
is possible, without absurdity, to doubt whether
1. Unendlicher Regress: B wird durch C, C there is a table at all, whereas it is not possible
durch D gerechtfertigt, usw. ad infinitum. to doubt the sense-data“ (Russell, 1912, S.
74). Sinneswahrnehmungen („sense-data“)
2. Rechtfertigungszirkel: B, der Grund für A, sind als Mentalzustände aufzufassen, von
46 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
denen wir unmittelbare Kenntnis („acquain- ssystem, das die Rückführung aller wis-
tance“) besitzen: „[...] Russell claims that senschaftlichen Begriffe auf „unmittelbar
awareness of sense data is direct, whereas Gegebenes“ erlauben sollte. Unmittelbar
awareness of tables is indirect.“ Das führt gegeben sind Carnap zufolge „die Bewusst-
dazu, dass „sense data ’stand between’ you seinsvorgänge oder Erlebnisse des Ichs“.
and the table, so to speak, that your aware- Diese bezeichnet er als „Elementarerleb-
ness of the table is only indirect. Sense data nisse“; sie sollen „ihrem Wesen nach unz-
play this mediating role in every example of erlegbare Einheiten“ darstellen, die „einfach
perceptual awareness, [...]“ (Gertler, 2011, S. so hinzunehmen“ sind, „wie sie sich geben“
89). (Carnap, 1928/1998, S. S. 86 ff.).
Parrallel zu Russell hat auch Moore ab 1910 Eine (zeitgenössische) Version der „Ac-
eine Theorie der Sinnesdaten vertreten. Auch quaintance Theory of Self-Knowledge“ wird
er plädiert dafür, zwischen Wahrnehmung z.B. von Fumerton vertreten. Zum unmittel-
und den von dieser unabhängig existieren- baren, d.h. nicht-inferentiellen Wissen schreibt
den Gegenständen zu unterscheiden: „[...] in er. „My suggestion is that one has a noninfer-
every sensation or idea we must distinguish entially justified belief that P when one has the
two elements, (1) the ’object’, or that in which thought that P and one is acquainted with the
one differs from another; and (2) ’conscious- fact that P“ (Fumerton, 1995, S. 75).
ness’, or that which all have in common - that Die „Acquaintance Theory of Self-
which makes them sensations or mental facts“ Knowledge“ lässt sich somit folgendermaßen
(Moore, 1903/1993, S. 37). zusammenfassen:
In analoger Weise sind auch für Carnap • Aufgrund unmittelbarer Kenntnis („ac-
Sätze der Realwissenschaften (Physik, Psy- quaintance“) sind wir mit unseren Sinnes-
chologie, etc.) rückführbar auf das wirklich daten vertraut, z.B. dass wir Schmerzen
Gegebene. Er schreibt: „Jeder Satz der Wis- haben.
senschaft muss sich bei logischer Analyse als
sinnvoll bewähren. Dabei wird entweder ge- • Aufgrund unmittelbarer Kenntnis sind wir
funden, dass es sich um eine Tautologie oder zu dem Urteil „Ich habe Schmerzen“, bzw.
um eine Kontradiktion (Negation einer Tautolo- „Schmerz ist vorhanden“ gelangt.
gie) handelt; dann gehört der Satz zum Ge-
• Aufgrund unmittelbarer Kenntnis sind wir
biet der Logik einschließlich der Mathematik.
uns der Korrespondenz zwischen un-
Oder der Satz ist eine gehaltvolle Aussage,
serem Schmerzempfinden und unserem
d.h. weder tautologisch noch kontradiktorisch;
Urteil „Schmerz ist vorhanden“ bewusst
dann ist es ein empirischer Satz. Er ist zurück-
(Gertler, 2011, S. 101).
führbar auf das Gegebene und daher grund-
sätzlich als wahr oder falsch entscheidbar“ Die Methode der Introspektion ist nicht nur für
(Carnap, 1931, S. 25 f.). die Erkenntnistheorie und die Philosophie des
Bereits im „Logischen Aufbau der Welt“ Geistes von großem Interesse, sondern auch
(1928) entwickelte Carnap ein Konstitution- für die modernen Neurowissenschaften. Dies
2012, 5 (1) Kognitive Neurophysiologie des Menschen 47
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
soll im nächsten Abschnitt kurz referiert wer- viele höherstufige kognitive Prozesse intro-
den. spektiv nicht zugänglich sind, wodurch sich die
Introspektion und Neurowissenschaften „anti-introspectivist view“ unter kognitiven Psy-
Die Frage, ob die Introspektion eine zuver- chologen deutlich verstärkte. Mandler (1975,
lässige und damit zulässige wissenschaftliche S. 245) fasst die Resultate dieser Experimente
Methode ist, wird seit Beginn des 20sten folgendermaßen zusammen: „There are many
Jahrhunderts sehr unterschiedlich bewertet. systems that cannot be brought into con-
Der Behaviorismus und sein Nachfolger, der sciousness, and probably most systems that
kognitive Funktionalismus, „declared war analyze the environment in first place have
on introspective psychology.“ (Schwitzgebel, that characteristic. In most of these cases,
2010, Zugriff: 03.02.2012) Es wurden im only the products of cognitive and mental
Wesentlichen vier Einwände vorgebracht: activities are available to consciousness.“
Der Bostoner Philosoph Daniel Dennett
1. „Introspective claims are unreliable be-
(1991, S. 122) kommt zu einer ähnlichen
cause they are not regularly replicated in
Einschätzung. Wir können nicht direkt
others.
wahrnehmen, „[...] what happens on our
2. Subjects confabulate (make up stories) retinas, in our ears, on the surface of our skin.
about what is going on in themselves What we actually experience is a product of
when they need to do so to make sense many processes of interpretation - editorial
of behaviour. processes, in effect.“ Dies hat Implikationen
für die Bedeutung der Introspektion und den
3. Introspection has access only to a tiny Cartesianischen Fundamentalismus insge-
fraction of what is going on in oneself cog- samt: „There is no single, definitive ’stream of
nitively. consciousness’, because there is no central
Headquarters, no Cartesian Theatre where ’it
4. It is impossible for introspection to access
all comes together’ for the perusal of a Cen-
brain states“ (Brook & Mandik, 2004, S.
tral Meaner. Instead of such a single stream
390).
(however wide), there are multiple channels in
Die Unzuverlässigkeit introspektiver Berichte which specialist circuits try, in parallel pande-
(Einwand 1.) ist Gegenstand von Wittgen- moniums, to do their various things, creating
steins Privatsprachenargument, das im folgen- Multiple Drafts as they go“ (Ebd., S. 253 f.).
den Abschnitt 2.6. ausführlich diskutiert wer- Aus Brooks und Mandiks Einwand 4. zieht
den wird. der Philosoph und Kognitionsforscher Paul
Brooks und Mandiks Einwände 2. und Churchland den gegenteiligen Schluss, näm-
3. fanden ab Anfang der 1960er Jahre lich dass Personen mit „[...] sufficient neu-
zunehmend empirische Bestätigung in Experi- roscientific education can introspect his or
menten, in denen die Methode der Introspek- her brain states as brain states“ (zit. nach:
tion selbst zum Untersuchungsgegenstand Mandik, 2006, S. 66). Churchland vertritt
wurde. Es zeigte sich insbesondere, dass seine „Introspection Thesis“ im Rahmen eines
48 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
eliminativen Materialismus, der unser laien- senschaftliche Befunde nicht auf eindeutige
haftes psychologisches Vokabular („folk psy- Weise mit entsprechenden Mentalzuständen
chology“) für überflüssig und irreführend hält. korreliert und insofern interpretationsbedürftig
Eine elaborierte zukünftige Kognitions- und sind (vgl. Ruchsow, Hermle & Kober, 2010).
Neurowissenschaft muss nicht mehr auf du- Insofern scheinen neurowissenschaftliche
biose mentale Entitäten rekurrieren, sondern Studien häufig zwischen der Skylla unzuver-
spricht stattdessen von neuronalen Zustän- lässiger introspektiver Probandenberichte und
den. Möchten wir an uns vertrauten Begrif- der Charybdis objektiver aber uneindeutiger
fen wie z.B. „Introspektion“ festhalten, dann Messergebnisse wählen zu müssen.
referieren diese nicht mehr auf Psychisches Wie gezeigt, geht der internalistische Fun-
sondern notwendigerweise auf Physisches. damentalismus davon aus, dass unsere Men-
Churchlands eliminativer Materialismus bzw. talzustände wesentlich privat und unmittelbar
Naturalismus ist von verschiedenen Seiten zugänglich sind, zwei Annahmen, die in den
nachhaltig kritisiert worden (z.B: Keil, 1993), nächsten beiden Abschnitten kritisch unter-
was im Rahmen dieser Arbeit jedoch nicht sucht werden sollen.
vertieft werden kann.
Mit dem zunehmenden Einfluss der 2.6. Privatheit
Kognitions- und Neurowissenschaften kam
Wittgensteins Überlegungen zur Privatheit
es zu einer Kehrtwende; die Methode der
bzw. zu den Möglichkeiten einer Privat-
Introspektion wurde wieder „salonfähig“, ins-
sprache in den Paragraphen 243 bis 315
besondere im Bereich der Emotionsforschung,
der „Philosophischen Untersuchungen“ (PU)
des „Mental Imagery“ und der sogenannten
lassen sich als kritische Auseinandersetzung
„Consciousness Studies“, die alle essentiell
mit dem Cartesianismus lesen. Unter einer
auf „subjective reports of experience“, also
Privatsprache versteht Wittgenstein folgen-
verbale „introspektive“ Berichte von Proban-
des: „Die Wörter dieser Sprache sollen sich
den, angewiesen sind. Dies hat die paradoxe
auf das beziehen, wovon nur der Sprechende
Konsequenz, „that neuroscience, the most sci-
wissen kann; auf seine unmittelbaren, pri-
entific of approaches to human nature to date,
vaten Empfindungen. Ein Anderer kann diese
has been forced to fall back onto a technique
Sprache also nicht verstehen.“ (Wittgenstein,
rejected as unscientific over 100 years ago!“
1953/1984, § 243 = PU 243)
(Brook & Mandik, 2004, S. 390)
Die Grundannahme einer derartigen pri-
In vielen empirischen Studien gibt es aber vaten Sprache lässt sich folgendermaßen
auch die Tendenz, „subjective reports of expe- zusammenfassen.:
rience“ bewusst zu umgehen und durch objek-
tivere Methoden zu ersetzen wie z.B. (seman- P1 „Sensations are private occurences“
tisches) Priming oder gleich auf bildgebende (Schroeder, 2001, S. 196). Meine Zahn-
Verfahren auszuweichen. Damit wird zwar der schmerzen sind aus diesem Grund
„subjektive Faktor“ Introspektion vermieden, anderen Personen nicht unmittelbar
aber in Kauf genommen, dass neurowis- zugänglich. Ebenso wenig kann ich mir
2012, 5 (1) Kognitive Neurophysiologie des Menschen 49
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
sicher sein, ob eine andere Person ähn- Sind Schmerzen, Käfer, etc aber wesentlich
liche Zahnschmerzen wie ich empfinden privat, dann ergibt sich als Konsequenz:
kann. „Wenn man die Grammatik des Ausdrucks der
Empfindung nach dem Muster von ’Gegen-
stand und Bezeichnung’ konstruiert, dann
2.6.1. „Das Rad gehört nicht zur Mas- fällt der Gegenstand als irrelevant aus der
chine“ (PU 271) Betrachtung heraus“ (PU 293).
Aus (P1) ergibt sich eine skeptische Konse-
2.7. Unmittelbarkeit
quenz, die Wittgenstein in PU 272 formuliert:
„Das Wesentliche am privaten Erlebnis ist Eine ausführliche Kritik an der Vorstellung
eigentlich nicht, dass Jeder sein eigenes Ex- unmittelbaren nicht-inferentiellen Wissens
emplar besitzt, sondern dass keiner weiß, ob findet sich bereits im 1. Kapitel von Hegels
der Andere auch dies hat, oder etwas an- „Philosophie des Geistes“ (Hegel, 1807/1973,
deres. Es wäre also die Annahme möglich S. 82 ff.). In der analytischen Philosophie
- obwohl nicht verifizierbar - ein Teil der verlief die Rezeptionsgeschichte Hegels sehr
Menschheit habe eine Rotempfindung, ein wechselhaft, um nicht zu sagen: dialektisch.
anderer Teil eine andere.“ Für Wittgenstein Nach einer kurzen hegelianischen Phase der
haben private psychische Ereignisse keinerlei „Gründungsväter“ der analytischen Philoso-
Funktion, vergleichbar einem überflüssigen phie, Moore und Russell, verstanden sich
Zahnrad in einer Maschine: „Hier möchte ich diese als dezidierte Anti-Hegelianer. Dieser
sagen: das Rad gehört nicht zur Maschine, Anti-Hegelianismus im Selbstverständnis der
das man drehen kann, ohne dass Anderes analytischen Philosophie ging so weit, dass
sich mitbewegt“ (PU 271). die oft gestellte Frage, warum sich die an-
Für Wittgenstein sind private mentale alytische Philosophie eigentlich „analytisch“
Ereignisse nicht nur überflüssig, sondern nenne, folgendermaßen beantwortet werden
im Rahmen einer öffentlichen Sprache nicht sollte: „’analytisch’ bedeutet ursprünglich
kommunizierbar. Mentalzustände sind wie genau ’anti-hegelisch’“ (Welsch, 2011, S. 71).
ein Käfer in einer Schachtel, zu der nur der Seit etwa Mitte der 1950er Jahre zeichnet
Besitzer der Schachtel Zugang hat. Der sich jedoch eine Wiederkehr Hegels im Bere-
Käfer ist also wesentlich „privat“. Wittgenstein ich der neueren analytischen Philosophie ab.
analysiert diese Situation folgendermaßen: Hier ist (neben John McDowell und Robert
„Niemand kann je in die Schachtel des An- Brandom) insbesondere der amerikanische
deren schaun; und jeder sagt, er wisse nur Philosoph Wilfrid Sellars zu nennen, der
vom Anblick seines Käfers, was ein Käfer seine Kritik an der Möglichkeit unmittelbaren
ist. - Da könnte es ja sein, dass Jeder ein Wissens unter dem Stichwort „Mythos des
anderes Ding in seiner Schachtel hätte. Ja, Gegebenen“ („myth of the given“) auch als
man könnte sich vorstellen, dass sich ein „Méditations Hegeliènnes“ verstanden wissen
solches Ding fortwährend veränderte. [...] die wollte (Sellars, 1956/1997, S. 45).
Schachtel könnte auch leer sein“ (PU 293). Nach Sellars lässt sich die Idee, dass „truth
50 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
bearers“ durch „truth makers“ verifiziert (bzw. idea that epistemic facts can be analyzed
falsifiziert) werden, nicht aufrecht erhalten: without remainder - even ’in principle’ - into
„Having a sense-impression is, by itself, an ex- non-epistemic facts whether phenomenal or
ample neither of knowledge nor of conscious behavioral, public or private [...] is, I believe, a
experience“ (Sellars, 1956/1997, S. 4), da radical mistake - a mistake of a piece with the
es sich bei Sinnesdaten nicht um (proposi- so-called ’naturalistic fallacy’ in ethics“ (Sellars
tionales) und damit wahrheitsfähiges Wissen 1956/1997, S. 19).
handelt. In anderen Worten: „[...] one might Aber nicht nur Descartes’ Introspektions-
think one is acquainted with certain sorts of begriff, sondern auch der diesem zugrunde
objects (sense data), determinate properties liegende Substanzbegriff war sehr umstritten
(this particular shade of yellow), generic uni- und wurde von empiristischen Philosophen
versals (being yellow, being colored), and, wie z.B. John Locke abgelehnt.
crucially, facts (my being in pain now, some-
thing’s being yellow). None of the items on
3. Locke
this list are the kinds of things that can be true
or false [...]. The object that is yellow, the yel- 3.1. Kritik am Substanzbegriff
lowness of the object, that fact that the object
is yellow are all neither true nor false“ (Fumer- Ähnlich wie Descartes wollte auch Locke
ton, 2009, Zugriff: 22.01.2012). Der Mythos einen radikalen Neuanfang in der Philosophie
des Gegebenen („Myth of the Given“) besteht machen. Er betrachtete sich als Hilfsarbeiter
nach Sellars in der Idee „that observation [...] („Under-Labourer“), der das Ziel hat, „[...]
is constituted by certain self-authenticating clearing Ground a little, and removing some
nonverbal episodes, the authority of which is of the Rubbish that lies in the way to Knowl-
transmitted to verbal and quasi-verbal perfor- edge [...]“. Durch Leidenschaften, Erziehung,
mances [...]“ (Sellars 1956/1997, S. 77). Die Gewohnheiten und Vorurteile wird unser Wis-
Vorstellung einer Fundierung unseres (propo- sen systematisch verzerrt und verfälscht.
sitionalen) Wissens durch mentale Episoden Insofern ist auch eine radikale Sprachkritik
lässt sich aber nicht halten: „For empirical erforderlich, denn „Vague and insignificant
knowledge, like its sophisticated extension, Forms of Speech and Abuse of Language
science, is rational, not because it has a have so long passed for Mysteries of Sci-
foundation but because it is a self-correcting ence; And hard or misapply’d Words, with
enterprise which can put any claim in jeopardy, little or no meaning, have, by Prescription
though not all at once“ (Sellars 1956/1997, S. such a Right to be mistaken for deep Learning
79). Bei dem Versuch, Wahrnehmungs- and height of Speculation, that it will not be
berichte, also epistemisches bzw. proposi- easy to persuade either those who speak or
tionales Wissen auf nicht-epistemisches bzw. those who hear that they are but the Covers
nicht-propositionales Wissen zu reduzieren, of Ignorance and hindrance of true Knowl-
handelt es sich nach Sellars vielmehr um edge“ (Locke, 1694/1979, S. 10). Das Ziel
einen naturalistischen Fehlschluss: „Now the dieser Demontage ist die Fundierung unseres
Wissens auf der Grundlage der Erfahrung,
2012, 5 (1) Kognitive Neurophysiologie des Menschen 51
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
die nach Locke die einzige Quelle sicherer essential to it“ (Locke 1694/1979, S. 335).
menschlicher Erkenntnis ist: „Let us then sup- „Consciousness“ liefert auch das gesuchte
pose the Mind to be, as we say, white Paper (naturalistische bzw. neurowissenschaftliche)
void of all Characters, without any Ideas. [...] Kriterium diachroner Identität: „For, since con-
Whence has it all the materials of Reason and sciousness always accompanies thinking, and
Knowledge? To this I answer, in one word, ’tis that which makes every one to be, what
From Experience [...]“ (Locke 1694/1979, S. he calls self, and thereby distinguishes himself
104). Insofern ist für Locke auch die Frage, ob from all other thinking things, in this alone con-
es eine cartesianische Seelensubstanz gibt sists personal Identity, i.e. the sameness of a
zu verneinen, da der Begriff „Substanz“ kein rational Being: And as far as this conscious-
Gegenstand möglicher Erfahrung ist. ness can be extended backwards to any past
Durch die Ablehnung des Substanzbegriffs Action or Thought, so far reaches the Identity
ergab sich jedoch eine neue Konstellation of that Person“ (Locke 1694/1979, S. 335). In
hinsichtlich der Identität von Personen. Für der Nachfolge Lockes wurde „consciousness“
Descartes war das Problem der diachronen meist mit „memory“ bzw. „Erinnerung“ über-
Identität von eher untergeordneter Bedeutung, setzt und das Kriterium diachroner Identität
da sein Substanzbegriff die Unsterblichkeit der dementsprechend als Erinnerungskriterium
Seele (= Persistenz der Person) garantierte. bezeichnet. Für Locke ist wichtig, dass man
Die Erklärung der synchronen Identität war sich nicht nur allgemein an eine bestimmte
jedoch weitaus problematischer, da sie sich Wahrnehmungssituation erinnert, sondern
dem Problem der Interaktion von res extensa dass die damalige Wahrnehmung sozusagen
und res cogitans stellen, bzw. den Begriff der „im selben Bewusstsein“ wie die jetzige erfolgt:
substantiellen Einheit inhaltlich füllen musste. „For as far as any intelligent Being can repeat
Für Locke ergab sich eine inverse Prob- the Idea of any past Action with the same
lematik: die synchrone Identität ist leichter zu consciousness it has of any present Action;
denken, während sich die transtemporale Ein- so far it is the same personal self“ (Locke
heit der Person (und damit die Unsterblichkeit 1694/1979, S. 336).
der Seele) ohne Substanzbegriff nur schwer
verstehen lässt. Locke war der erste, der den Begriff der
Person im Gegensatz zur Scholastik und zum
Cartesianismus allein durch den des Bewusst-
3.2. Diachrone personale Identität
seins bestimmte (Thiel, 1997, S. 163; Gillitzer,
Locke definiert Person folgendermaßen: „[...] 2001, S. 111). Die diachrone Einheit der
we must consider what Person stands for; Person konstituiert sich im Selbstbewusstsein
which, I think, is a thinking intelligent Being, und ist damit epistemisch ausschließlich in
that has reason and reflection, and can con- der Ersten-Person-Perspektive zugänglich.
sider itself as itself, the same thinking thing, Quante nennt dies die „These der erstper-
in different times and places; which it does sönlichen Natur personaler Einheit“ (kurz:
only by that consciousness which is insepa- Erstpersönlichkeitsthese; Quante, 2007, S.
rable from thinking, and, as it seems to me, 57).
52 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
Darüber hinaus vertritt Locke eine „Unab- (Olson, 2010, Zugriff: 22.01.2012).
hängigkeitsthese“, die besagt, dass person- Dieser Transitivitätseinwand lässt sich je-
ale Einheit „unabhängig von der Identität einer doch dadurch entkräften, dass man Lockes
selbstbewusstseinstranszendenten Substanz“ Erinnerungsrelation im Sinne einer psychol-
ist (Quante, 2007, S. 58 f.).. In Lockes Worten: ogischen Verbundenheit („connectedness“)
„For it being the same consciousness that ersetzt durch die schwächere Relation der
makes a Man be himself to himself, personal psychologischen Kontinuität („continuity“), für
Identity depends on that only, whether it be an- die gilt: „Zwischen dem Bewusstseinszus-
nexed only to one individual Substance, or can tand einer Person zum Zeitpunkt t0 und dem
be continued in a succession of several Sub- Bewusstseinszustand einer Person zum Zeit-
stances. [...] The same consciousness unit- punkt t1 besteht genau dann psychologische
ing those distant Actions into the same Person, Kontinuität, wenn es zwischen diesen beiden
whatever Substances contributed to their Pro- Bewusstseinszuständen ein stetiges Band
duction“(Locke 1694/1979, S. 336). von Bewusstseinszuständen gibt, die untere-
Drittens ist Locke der Meinung, dass per- inander in der Relation der psychologischen
sonale Einheit ein komplexes Phänomen ist Verbundenheit stehen. Gibt es ein solches
und sich (z.B. durch das Erinnerungskriterium) Band, dann handelt es sich bei den beiden
auf informative Weise weiter analysieren lässt. Bewusstseinszuständen zu t0 und t1 um die
Quante nennt dies „die These der internen Bewusstseinszustände ein und derselben
Komplexität personaler Einheit - kurz: die Person“ (Quante, 2007, S. 47).
Komplexitätsthese“ (Quante, 2007, S. 58).
Butler wies darauf hin, dass Erinnerungen
stets eine Person implizieren, die die Erin-
4. Reid und Butler nerungen hat. Das Erinnerungskriterium setzt
Lockes Lösungsansatz wurde insbesondere also personale Identität voraus und kann diese
von Reid und Butler kritisiert. Reid zeigt niemals konstituieren: „And one should re-
anhand des „Brave Officer Paradox“, dass ally think it self-evident, that consciousess of
Lockes Erinnerungskriterium nicht stichhaltig personal identity presupposes, and therefore
ist: „Suppose a brave officer to have been cannot constitute, personal identity, any more
flogged when a boy at school for robbing an than knowledge, in any other case , can con-
orchard, to have taken a standard from the stitute truth, which it presupposes“ (Butler,
enemy in his first campaign, and to have been 1736/1975, S. 100).
made a general in advanced life; suppose, Butlers Zirkularitätseinwand lässt sich durch
also, which must be admitted to be possible, die Annahme sogenannter „q-memories“
that, when made a general, he was conscious entkräften, ein Vorschlag, der auf Sydney
of his taking a standard, but had absolutely Shoemaker zurückgeht. Nach Shoemaker
lost the consciousness of his flogging“ (Reid, sind q-memories durch einen fehlenden im-
1785/1975, S. 114). Reids Kritik lässt sich pliziten Subjektbezug gekennzeichnet, so
pointiert folgendermaßen zusammenfassen: dass sie nicht-zirkulär personale Identität kon-
„Identity is transitive; memory continuity is not“ stituieren können: „One way of characterizing
2012, 5 (1) Kognitive Neurophysiologie des Menschen 53
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
the difference between quasi-remembering z.B. durch Schlaf, Narkosen, Ohnmachten,
and remembering is by saying that the former etc. dazu führen „that I have never existed at
is subject to a weaker previous awareness any time when I was completely unconscious“
condition than the latter. Whereas someone’s (Olson, 2010, Zugriff: 22.01.2012).
claim to remember a past event implies that he Auch der New Yorker Philosoph Thomas
himself was aware of the event at the time of Nagel definiert personale Identität anhand
its occurrence, the claim to quasi-remember a des physischen Identitätskriteriums. Die Mini-
past event implies only that someone or other malanforderung an ein physikalisches Korrelat
was aware of it“ (Shoemaker, 1970/2003, personaler Identität besteht darin, „bearer of
S. 24). Jedoch muss sich auch ein Vertei- mental states and the cause of their continuity“
diger von Lockes Erinnerungskriterium, der zu sein (Nagel, 1986, S. 40). Hypothetisch
q-memories als basal ansetzt, fragen lassen, nimmt Nagel an, dass am ehesten das intakte
„auf welcher Grundlage er von der Menge der Gehirn diesen Anforderungen Genüge tut. Ein
Quasi-Erinnerungen zu der Menge der Erin- alternativer Kandidat ist der menschliche Kör-
nerungen kommen möchte“ (Quante, 2007, S. per, der eng mit den Hirnfunktionen verknüpft
90). ist, jedoch „[...] the brain is the only part of
me whose destruction I could not possibly
survive. The brain, but not the rest of the
5. Das physische animal, is essential to the self“. Zusammen-
Kontinuitätskriterium fassend kann (mit milder Übertreibung) gesagt
werden: „ [...] I am my brain [...]“ (Nagel, 1986,
Quante und Olson plädieren aufgrund der S. 40). Das Gehirn ist die notwendige und
geschilderten Schwierigkeiten des Erin- hinreichende Bedingung personaler Identität
nerungskriterium für ein anderes naturalis- (Northoff, 2001, S. 131-132), da es die biol-
tisches Kriterium diachroner Identität, das ph- ogische Grundlage aller mentalen Vorgänge
ysisches Kontinuitätskriterium. Nach Quante wie Erinnerungen aber auch des „Bewusst-
lässt sich Butlers Zirkularitätseinwand effektiv seinsstroms“ ist und somit ein Fortbestehen
durch die Annahme aus dem Weg räumen, der Person nach (Teil-)verlust des Gehirns
„dass der Träger der mentalen Episoden nicht unmöglich erscheint.
die Person, sondern ein [...] menschlicher
Organismus ist“ (Quante, 2007, S. 90). Zu 6. Parfit
diesem Schluss kommt auch Olson, der für
einen „somatic approach“ bzw. „animalism“ Mit Hilfe eines Gedankenexperiments weist
plädiert: „There appears to be a thinking Parfit nach, dass Nagels Slogan „I am my
animal located where you are. It also ap- brain“ nicht ausreicht, um numerische Identität
pears that you are the thinking thing - the zu garantieren: „Suppose next that I need
only one - located there“. Olsons Überlegung surgery. All of my brain cells have a defect
ist auch durch die absurde Konsequenz des which, in time, would be fatal. But a surgeon
Erinnerungskriteriums motiviert, dass alle can replace all these cells. He can insert new
Unterbrechungen des Bewusstseinsstroms cells that are exact replicas of the existing
54 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
cells except that they have no defect“ (Parfit, nicht halten. Die Aufgabe des Substanzbe-
1984, S. 474). Parfit unterscheidet zwei Oper- griffs führt in der Folgezeit zu einer Ver-
ationsprozeduren: In der ersten („Case One“) lagerung der Diskussion von der synchronen
werden alle Nervenzellen meines Gehirns zur diachronen Identität. Aber auch die (natu-
in einer Serie von 100 Operationen schrit- ralistischen ) Kriterien der Erinnerung und der
tweise entfernt und durch neue ersetzt. Bei physischen Kontinuität, die im Zusammenhang
der anderen Operationsart („Case Two“) wird der diachronen Identität formuliert wurden,
in einem Schritt mein ganzes Gehirn aus- sind mit einer Vielzahl von Schwierigkeiten
getauscht. Bei der ersten Operation ist die belastet.
Kontinuität meiner Person gegeben, bei der Im folgenden sollen Überlegungen des
zweiten jedoch nicht: „ There is a real dif- kanadischen Philosophen Charles Taylor zur
ference between these cases. In Case One, narrativen Identität vorgestellt werden, der
each of the new parts of my brain is for a time sich nicht nur an der analytischen Philosophie,
joined to the rest of my brain. This enables sondern insbesondere auch an kontinentaleu-
each new part to become part of my brain. ropäischen Traditionslinien orientiert.
When the first new part is inserted, and joined
to the rest of my brain, it wins the title to be
7. Taylor
as much part of my brain as the old parts.
When the second new part is inserted, it too 7.1. Selbstinterpretation
becomes a part of my brain. This is true of
every new part, because there is a time when Taylors Überlegungen zur personalen Identität
this part is joined to what then counts as the knüpfen in vielen Punkten an Wittgenstein an,
rest of my brain. mit dem er sich sehr intensiv auseinanderge-
setzt hat (z.B. Taylor, 1972; 1988a; 1995;
In Case Two, things are different. There are 2010). Taylor ist jedoch nicht nur einem an-
no times when each part is joined to the rest of alytischen Ansatz verpflichtet, sondern steht
my brain. Because of this, the new parts do not u.a. in den Traditionslinien von Hermeneu-
count as parts of my brain. My brain ceases to tik, Anthropologie und Deutschem Idealismus
exist“ (Parfit, 1984, S. 474 f.). Die erste Art der (hier insbesondere Hegel). Von Axel Honneth
Operation werde ich (als Person) überleben, wurde er als ein Parteigänger der Hermeneutik
die zweite jedoch nicht, obwohl das Endergeb- im Felde der analytischen Wissenschaftstheo-
nis in beiden Fällen dasselbe ist. Folglich ist rie bezeichnet (in: Taylor, 1988b, S. 296).
der Slogan „I am my brain“ nicht hinreichend, Für Taylor sind Personen wesentlich „self-
um numerische Identität zu gewährleisten. interpreting animals“ (Taylor, 1985a, S. 45 ff.)
Zusammenfassend bleibt festzuhalten, dass und „dialogical selves“ (Taylor, 1995, S. 230).
weder Descartes’ noch Lockes Ansatz eine Sie sind also durch ihre Fähigkeit zur Selbstin-
tragfähige Lösung des Problems der per- terpretation und zum sprachlich-dialogischen
sonalen Identität darstellt. Descartes’ Sub- Austausch mit anderen Menschen gekennze-
stanzbegriff lässt sich im Rahmen des zeit- ichnet. Ähnlich wie für Wittgenstein ist für Tay-
genössischen naturalistischen Paradigmas lor Sprache ein intrinsisch soziales Phänomen:
2012, 5 (1) Kognitive Neurophysiologie des Menschen 55
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
„The matter talked about is no longer just 7.3. Hermeneutik
for me or for you, but for us“ (Taylor, 1985a,
S. 260). Insofern verfehlen wir völlig das Wie Gadamer ist auch Taylor der Auffas-
Wesentliche, „if we remain with the monolog- sung, dass Menschen immer schon in eine
ical model of the subject, and think of all states bestimmte Sprachgemeinschaft, bestimmte
of awareness, knowledge, belief, attending to, Traditionen und ein bestimmtes Verständ-
as ultimately explicable as states of individu- nis der Welt hineingeboren sind, das die
als“ (Taylor, 1985a, S. 265). Basis ihres Verstehens bildet („Geworfen-
heit“ im Sinne Heideggers). Intersubjektivität
geht der Subjektivität voraus, „we are aware
of the world through a ’we’ before we are
7.2. Sprache through an ’I’“ (Taylor, 1985b, S. 40). Insofern
befindet sich jeder in einem hermeneutis-
Ausgehend von dieser sozialen und dialogis-
chen Zirkel, weil die Interpretationen unserer
chen Dimension der Sprache kritisiert Tay-
Umwelt selbst schon Resultat vorgängiger
lor die zeitgenössischen Sprachauffassungen
Interpretationen sind (Breuer, 2000, S. 23).
als naturalistisch, worunter er Theorien ver-
Verstehen hat immer den Doppelcharakter
steht, die von einem Beobachter über einen
der Teilnahme an einem Sinngeschehen,
beobachteten Gegenstand entwickelt werden,
das dem Subjekt vorausgeht und sein Be-
an dem er nicht beteiligt ist.
greifen ermöglicht und einem Sichverstehen
Taylor stellt dieser naturalistischen eine (Angehrn, 2004, S. 774): Wie ich die Welt
romantisch-expressivistische Sprachauffas- auffasse, ist davon abhängig, wie ich den Sinn
sung gegenüber, die er auch als Herder- meines Daseins interpretiere, wie umgekehrt
Humboldt-Hamann-Theorie bzw. als „triple-H mein Selbstverständnis nicht losgelöst von
theory“ bezeichnet (Taylor, 1985a, S. 256). meiner Sicht auf die Dinge zustande kommt
Die Expressivität von Sprache verdeutlicht bzw. in Honneths Worten: „Soziales Handeln
auch deren dialogischen Charakter, indem sie ist ohne Bezugnahme auf das situationsge-
eine bestimmte Art der Beziehung zu einem bundene Selbstverständnis der handelnden
Gegenüber ausdrückt. Sprechen heißt dann Subjekte gar nicht angemessen aufzufassen;
„to put it ’out there’, to have it out before us, to der Erklärung einer Handlung muss daher ein
be ’up front’ about it“ (Taylor, 1985a, S. 264). hermeneutisches Verstehen der jeder unmit-
Sprache erzeugt etwas, „what one might call a telbaren Beobachtung entzogenen Perspek-
public space, or a common vantage point from tive des Handelnden unbedingt vorhergehen“
which we survey the world together“ (Taylor, (in: Taylor, 1988b, S. 299).“
1985a, S. 259). Etwas ausdrücken bedeutet Taylor unterscheidet dementsprechend zwei
„to place it in public space, and thus to bring Interpretationsebenen: Auf einer präreflexiven
us together qua participants in a common act Ebene ist Personen ein Selbst- und Weltver-
of focussing“ (Taylor, 1985a, S. 260). ständnis vorgegeben, das primär und zum
größten Teil implizit und nicht artikuliert ist (vgl.
Rosa, 1998, S. 200). Dem reflexiven Bewusst-
56 Human Cognitive Neurophysiology 2012, 5 (1)
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
sein wird diese gesamte erste (präreflexive) Lebensgüter sind demgegenüber Ziele,
Interpretationsebene dann zum Gegenstand Prinzipien und Ideale, die Menschen in ihrem
einer zweiten Interpretationsebene, in der jene Leben zu verwirklichen suchen, während Hy-
auf ihre Bedeutungen und ihren Sinn befragt pergüter Leitwerte darstellen, die Kohärenz
und sprachlich artikuliert wird. und eine einheitliche Orientierung in unser
Leben zu bringen vermögen
7.4. Moralische Topographien
7.5. Narrative Identität
Ein „selbstinterpretierendes Tier“ zu sein
heißt für Taylor u.a. auch, sich der Frage zu Nach Taylor müssen wir das eigene Leben im
stellen „Who I desire to be?“ (Rosa, 1998, Sinne einer narrativen Darstellung begreifen.
S. 98) und sich durch ihre Beantwortung in Es genügt nicht, dass ein Individuum über eine
einem moralischen Raum zu verorten. Unsere identitätsstiftende moralische Landkarte ver-
Identität als Personen wird aus seiner Sicht fügt bzw. sich im moralischen Raum orien-
entscheidend durch fundamentale Wertungen tiert. Die Ausbildung und der Erhalt person-
mitbestimmt, so dass sich ein unauflöslicher aler Identität verlangt vielmehr, dass es in der
Zusammenhang von Personalität und der Lage ist, „sich auf dieser Landkarte zu posi-
Konzeption des Guten ergibt. tionieren, d. h. seinen jeweiligen aktuellen Ort
Taylor unterscheidet (mit zunehmender im Hinblick auf die verzeichneten Güter (und
Wertigkeit) zwischen „Lebensgütern“ („Life Übel) zu bestimmen sowie einen Sinn für die
Goods“), „Hypergütern“ („Hypergoods“) und Bewegungsrichtung des eigenen Lebens und
„konstitutiven Gütern“ („Constitutive Goods“). Handelns vor dem Hintergrund dieser Güter
Konstitutive Güter sind Moralquellen, d. h. „it zu entwickeln“ (Rosa, 1998, S. 166). Person-
is a something the love of which empowers ale Identität hat eine unhintergehbare zeitliche
us to do and be good“ (Taylor, 1989, S. 93). Struktur, der die narrative Darstellung der eige-
Dabei leistet das konstitutive Gut mehr als nur nen Lebensgeschichte am ehesten gerecht
die Bestimmung des Inhalts der Moraltheorie. wird. Personsein erschöpft sich nicht in der
„Love of it is what empowers us to be good. Bestimmung dessen, was jemand ist, sondern
And hence also loving it is part of what it umfasst auch immer, was jemand geworden
is to be a good human being.“. Moralthe- ist (oder hätte werden können) bzw. was er
orie gebietet also nicht nur, in bestimmter in Zukunft werden wird. Der Mensch ist ein
Weise zu handeln und bestimmte moralische Geschichten erzählendes Wesen: „It has often
Eigenschaften an den Tag zu legen, sondern been remarked that making sense of one’s life
schreibt auch vor, zu lieben, was gut ist: „To as a story is also, like orientation to the good,
love the constitutive good [...] is to be strongly not an optional extra; that our lives exist also in
motivated in just that way which is defined this space of questions, which only a coherent
as part of doing the good [...]. That is why narrative can answer. In order to have a sense
being good involves loving something and not of who we are, we have to have a notion of how
just doing something“ (Taylor, 1989, S. 533 f., we have become, and of where we are going“
Anm. 2). (Taylor, 1989, S. 47).
2012, 5 (1) Kognitive Neurophysiologie des Menschen 57
M. Ruchsow — Personale Identität aus Sicht der Neurowissenschaften
Kritisch anzumerken bleibt, dass Narratio- Butler, J. (1736/1975). Of Personal Identity. In
nen ebenfalls ein intaktes (autobiographis- J. Perry (Hrsg.), Personal Identity. Berkeley,
ches) Gedächtnis voraussetzen und sich Los Angeles, London: University of Califor-
damit letztendlich als eine Variante des nia Press, 99-105.
Erinnerungskriteriums entpuppen. Sie kön-
nen somit kaum die Identität der Person Carnap, R. (1928/1998). Der logische Aufbau
garantieren, sondern haben diese vielmehr der Welt. Hamburg: Meiner.
zur Voraussetzung. Taylors großes Verdi- Carnap, R. (1931). Die alte und die neue
enst besteht jedoch darin, auf die soziale Logik. Erkenntnis, 1, 12-26.
Dimension personaler Identität hingewiesen
zu haben. Sein Ansatz müsste durch Über- Dennett, D. C. (1991). Consciousness Ex-
legungen des Sozialkonstruktivismus ergänzt plained. London: The Penguin Press.
werden (z.B. Smith, 2010; Bakhurst, 2011),
was jedoch den Rahmen dieser Arbeit spren- Descartes, R. (1641/2009). Meditationen. Mit
gen würde. sämtlichen Einwänden und Erwiderungen,
Hamburg: Meiner.
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60 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
Abstracts of the 20thGerman about the ball flight. This anticipation task was
contrasted with observing a player bouncing a
EEG/EP Mapping Meeting, ball with no need to anticipate. Results showed
Giessen, October 14-16, 2011 a significantly better anticipation performance
in expert tennis players compared to novices,
t(30) = 4.19, p < .001. The functional imaging
data showed enhanced activation in the main
areas of the AON when contrasting the antic-
The influence of expertise on neural pro- ipation and nonanticipation tasks. More pre-
cesses when anticipating action effects cisely, the premotor cortex, the inferior frontal
in tennis N. Balser (1), S. Pilgramm (1,2), gyrus, and the superior parietal lobe showed
M. Bischoff (1,2), B. Lorey (1,2), K. Zentgraf greater activation when anticipation of stroke
(3), R. Stark, A (2). M. Williams (4) & J. direction was contrasted with mere observa-
Munzert (1) (1) Institut für Sportwissenschaft, tion. Compared with novices, experts showed
Justus-Liebig-Universität Gießen, D-35394 greater activation in the cerebellum during the
Gießen, Germany; (2) Bender Institute of Neu- anticipation condition. An additional covariate
roimaging, Justus-Liebig-Universität Gießen, tennis experiencerevealed that the cerebellar
D-35394 Gießen, Germany; (3) Institut für activation in the experts was higher for players
Sportwissenschaft, Universität Bern, CH-3012 who had longer tennis experience. Our find-
Bern, Switzerland; (4) Faculty of Health Sci- ings support the theory that the AON is used
ences, University of Sydney, AUS-NSW 2141 to anticipate the effects of observed actions
Sydney, Australia (Zentgraf et al., 2011). The stronger activation
It has recently been proposed that the action in the cerebellum suggests that experts rely
observation network (AON) (Zentgraf et al., on internal models when predicting the conse-
2011) plays an important role in the anticipa- quences of an action.
tion of action effects. The cerebellum could be
particularly crucial for predicting action conse- Inhibitory control assessed through simul-
quences because of its role in the control of taneous EEG-fMRI imaging: a pilot study
executed movements (Miall, 2003) and its in- Sarah Baumeister (1), Sarah Hohmann (1),
clusion in the AON (Cross et al., 2009). To in- Isabella Wolf (1), Michael Plichta (2), Stefanie
vestigate whether expertise in sport influences Rechtsteiner (1), Maria Zangl (5), Matthias
the activation of this network during an an- Ruf (3), Christine Niemeyer (4), Peter Kirsch
ticipation task, 16 expert tennis players and (4), Herta Flor (5), Andreas Meyer-Lindenberg
16 novices observed videos of tennis strokes. (2), Martin Holtmann (1,6), Vasil Kolev (1,7),
While lying in an fMRI scanner, participants Juliana Yordanova (1,7), Tobias Banaschewski
observed videos showing an opponent’s fore- (1), Daniel Brandeis (1,8) (1) Department of
hand strokes that were occluded at the mo- Child and Adolescent Psychiatry and Psy-
ment of ball-racket contact. The participants’ chotherapy, CIMH Mannheim; (2) Depart-
task was to anticipate the direction of the ob- ment of Psychiatry and Psychotherapy, CIMH
served strokes without having any information Mannheim; (3) Department Neuroimaging,
2012, 5 (1) Kognitive Neurophysiologie des Menschen 61
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
CIMH Mannheim; (4) Department of Clinical (p<.01 at Cz, compared to neutral flankers)
Psychology, CIMH Mannheim; (5) Department NoGo positivity lasting from about 460 to
of Cognitive and Clinical Neuroscience, CIMH 660ms. Furthermore, we found a significantly
Mannheim; (6) Child and Adolescent Psychi- (p<.05 at Cz) enhanced N2 in the NoGo
atry, Ruhr-University Bochum, Germany; (7) compared to the Neutral condition.
Institute of Neurobiology, Bulgarian Academy Simultaneous EEG-fMRI during a Flanker/NoGo
of Sciences, Sofia, Bulgaria; (8) Department task showed landmark effects of inhibitory con-
of Child and Adolescent Psychiatry, University trol in both imaging modalities with a simple
of Zürich 7 min paradigm suitable for adults as well as
Inhibitory control shows individual and ge- ADHD children. In an ongoing study we now
netic variation and is impaired in Attention examine whether inhibitory control is impaired
Deficit Hyperactivity Disorder (ADHD). Neuro- in ADHD compared to control groups, and
feedback is an emerging nonpharmacological improves after neurofeedback training.
treatment for ADHD (Holtmann et al., 2009), Supported by the SFB 636 and NewMeds
but how changes in the inhibitory pathway projects.
contribute to the treatment outcome is still un-
Manipulierte audiovisuelle Pointlight Dis-
clear. Advanced imaging with combined EEG
plays beeinflussen die Nutzung interner
(electroencephalography) and fMRI (func-
Modelle zur Prädiktion M. Bischoff (1,2), B.
tional magnetic resonance imaging) should
Lorey (1,2), S. Pilgramm (1,2), K. Zentgraf
optimally characterize individual variation
(3,2), R. Stark (2), D. Vaitl (2) & J. Munz-
and treatment-induced changes of inhibitory
ert (1,2) (1) Institut für Sportwissenschaft,
control.
Justus-Liebig-Universität Giessen, D-35394,
In this pilot study we explored the feasibility Deutschland; (2) Bender Institute of Neu-
of simultaneous recording of 64 channel EEG roimaging, Justus-Liebig-Universität Giessen,
and 3T (Siemens TIM Trio) fMRI to probe con- D-35394, Deutschland; (3) Institut für
flict processing and inhibitory control using a Sportwissenschaft, Universität Bern, CH-
Flanker/NoGo task (Meyer-Lindenberg et al., 3012, Schweiz Um Handlungen und Hand-
2006). The task requires a left or right but- lungseffekte zu verstehen, werden im Hirn des
ton press, corresponding to the central arrow, Beobachters interne Modelle der Bewegung
when flankers are either other arrows or boxes. mit der wahrgenommenen Bewegung ver-
The button press has to be inhibited when glichen. Solche Handlungsrepräsentationen
flankers are „XX“. liegen in verschiedenen Sinnesmodalitäten
The fMRI analysis (N=23) revealed robust vor, die Verarbeitung interner Modelle sollte
NoGo vs. Neutral effects, with increased acti- also durch Manipulation multisensorischer
vation to NoGo stimuli in an inhibitory network Wahrnehmung beeinflussbar sein. Wird bei
involving bilateral insula and the ACC (p<.05, der visuellen Handlungswahrnehmung zusät-
FWE corrected). After gradient, ballistocardio- zliche auditive Information verwendet und wie
gram and ICA corrections, the corresponding wirkt sich widersprüchliche auditive Informa-
EEG analysis (N=17) revealed a significant tion aus?
62 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
Ein Tischtennis-Spieler, der seinen Gegen- sueller Stimulation höhere Aktivierung als bei
spieler während dessen Schlagausführung der unmerklich inkongruenten. Interne Mod-
beobachtet, nutzt auch den Zeitpunkt des elle sind also multisensorisch repräsentiert
Schläger-Ball-Kontakts zur Einschätzung des und als funktionelle Grundlage der Prädiktion
Schlages. Wird die visuelle Bewegungsinfor- zugänglich für multisensorische Kongruenzef-
mation reduziert in Form von Pointlight Dis- fekte.
plays (PLD) und werden Ball sowie Schläger
dabei ausgeblendet, dann zeigt der Ton den Functional and clinical abnormalities in
Schläger-Ball-Kontakt an und vervollständigt patientes with panic disorder and their
im Vergleich zu einer äquivalenten aber ton- treatment options S. Deppermann (1), S.
losen Bewegung das interne Modell. Sickinger (1), N. Vennewald (2), A.J. Fallgat-
ter (1), P. Zwanzger (2) & A.-C. Ehlis (1) (1)
Sechsundzwanzig Beobachter wurden mit Münster, (2) Tübingen
funktioneller MRT untersucht, während Repetitive transcranial magnetic stimulation
sie PLDs eines gegnerischen Tischtennis- (rTMS) has already been suggested as an
Spielers bezüglich der Richtung des resul- alternative treatment method in a variety of
tierenden Ballflugs einschätzten (die Alterna- psychological disorders such as major de-
tive war „Cross oder Longline“). In den Videos pression. Another frequent disabling disease
waren nur die Marker für beide Schultern, den is panic disorder (PD). PD is characterized
rechten Ellenbogen und das rechte Handge- by the sudden onset of unexpected panic
lenk des Spielers zu sehen, sowie zwei statis- attacks often resulting in the avoidance of a
che Markierungen der gegenüberliegenden multitude of situations (agoraphobia). The
Plattenkante. Der Schläger-Ball-Kontakt kon- neurobiological correlate of these symptoms
nte allein durch ein entsprechendes Tonsignal is believed to be a dysfunction of the fear
markiert werden. Dieser Ton wurde entweder network including hyperactivity of the amyg-
gar nicht präsentiert, zum Bewegungsbe- dala and decreased activity of the prefrontal
ginn – also offensichtlich zu früh, 120ms vor cortex. Accordingly, a model of inadequate
dem eigentlichen Zeitpunkt – unmerklich zu top-down governance in anxiety disorders has
früh – oder zum Zeitpunkt des Schläger-Ball- been established. Whereas functional mag-
Kontakts. netic resonance imaging (fMRI) data could
Die Probanden zeigten eine erhöhte Per- show that cognitive behavioral therapy (CBT)
formanz, wenn der Ton zeitlich kongruent is capable of normalizing both exaggerated
gesetzt war. Region-of-Interest Analysen der amygdala activity and prefrontal hypofunction,
fMRT-Daten ergaben als sensitiv für die Kon- the effects of rTMS as an additional therapeu-
gruenz multisensorische Integrationsareale im tic tool have not been investigated much so
temporo-okzipitalen Gyrus temporalis medius far. Even though CBT is an effective treatment
und im anterioren intraparietalen Sulcus. Die method it has the disadvantage of a delayed
Rekrutierung interner Modelle im ventralen onset of its effect and is not always sufficient
prämotorischen Kortex und Gyrus frontalis so that additional psychopharmacological
inferior (BA44) zeigte bei kongruenter audiovi- medication might be needed. Therefore the
2012, 5 (1) Kognitive Neurophysiologie des Menschen 63
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
aim of this study was to investigate the ap- on a monitor. The interstimulusinterval (ISI) of
plication of sham controlled prefrontal rTMS the presentation has been set either to 3 sec-
during CBT in order to enhance the impact onds, to 6 seconds or varying between 3 and
of the therapy. To quantify and hence being 6 seconds (in 125 msec steps).
able to evaluate the effects of rTMS in terms of As expected the results indicated the fastest
helping to normalize the prefrontal hypoactivity RT for the 3 sec ISI presentation, followed by
the neuroimaging method functional near in- the 6 sec ISI. The varying ISI yielded the slow-
frared spectroscopy (fNIRS) was chosen. One est RT. EEG data indicated significant differ-
major advantage of this method over fMRI is ences in the timecourse of FmT activity at fron-
its compliance with especially PD patients. tocentral and central locations. While for the
During the NIRS recording patients performed 6 second ISI as well as for the varying ISI
an emotional (emotional stroop/Westphal FmTremained on a relatively stable level dur-
paradigm) as well as a cognitive task (verbal ing the last second preceding the task, in the
fluency). The results are not only ground- 3 sec ISI condition a specific preparation pat-
breaking regarding the future of the treatment ternëmerged. In this task FmT increased sig-
of PD but also demonstrate the benefits of nificantly from a very low level to a level ex-
fNIRS as an imaging method to assess higher ceeding the FmT activity of the other task con-
cortical structures when other methods such ditions. Taken together these data indicate that
as fMRI are less convenient. the predictability of a stimulus leads to varying
preparatory attentional processes that can be
Frontal Midline Theta in Simple Reaction detected by FmT.
Time Tasks: Comparing Predictable and
Unpredictable Stimulus Onset M. Doppel- The neuronal basis of the development of
mayr & E. Weber FB Psychologie, Universität humans into speaking and cultural beings
Salzburg, Hellbrunnerstr 34, 5020 Salzburg, Duncker, H.-R. Institut für Anatomie und Zellbi-
Österreich ologie der Universität Gießen During the phy-
In several types of sport, fast reaction times logenetic development of humankind, both the
are of upmost importance. To gain a better un- structures and functions of the human body
derstanding of the cognitive processes that oc- were subjected to evolutionarily-driven biolog-
cur in the prestimulusinterval of reactions (as ical modifications. The body has enlarged,
for example the start of a 100m sprint), we in- has developed new proportions with respect to
vestigated changes of the EEG frontal midline its extremities, and has dramatically increased
theta (FmT), which is known to be related to functional capabilities. Each successive Homo
working memory, action regulation, and sus- species exhibits an enlarged cerebrum, which
tained attention. has developed as a consequence of new ter-
EEG and simple reaction times of 18 voluntary tiary association areas, which make up 50
participants have been recorded during three By migration out of the tropical rain forest, their
different RT- tasks. In all tasks participants ancestral living area, into the enlarging East
were instructed to react (push a button) as fast African savannahs, developing humans could
as possible whenever a circle was presented no longer make use of their inherited feed-
64 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
ing manners and behaviour. As such, they acteristic of including the functional meaning of
were forced to invent all necessary activities these objects or events for the communicating
for their nourishment and defence, including humans, which are represented together with
their social communication in the extended sa- the objects or events in the cerebral memory
vannahs. The inventions of single individu- of the persons.
als were adopted by most members of the This gesticulatory communication has devel-
community, including the successful handing oped – very slowly and in a stepwise fashion
down of these new abilities to descendants. – in combination with linguistic sounds. Only
Through these developments, social commu- with the appearance of modern humans, with
nities drove the formation of cultural communi- their ability to produce all vowels, has a full
ties, with common use of, and communication capacity for spoken communication developed.
about, these abilities and activities, which are By the long phylogeny of mammals in the sub-
collected into, and thereby enlarged, their his- terranean or nocturnal habitat, their auditory
torical development. systems became the most important sensory
system for social and emotional interaction. In
All these new capabilities and communication the language communication of modern hu-
abilities could not be integrated into the genetic mans, a direct coupling of the brains of inter-
codes of the developing humans, but could be locutors occurs: The speaker’s production of
stored as memory in the newly-developed ter- cortical excitations for pronouncing words and
tiary association areas of the cerebrum. For sentences induces in the brain of the listener
handing down of these capabilities to descen- comparable excitations, together with specific
dants, developing humans depended on the associations. These capabilities of acoustic
imitation of these activities and actions, by ob- communication depend not only on the mutual
serving the activities of their parents and other understanding of interlocutors, but also one
community members. These imitations, which the handing down of complex thoughts to all
are used occasionally by higher apes, were in- of the members of the community, and to their
tensively used by developing humans to hand minors. All cultural developments of modern
down abilities to descendants. However, the humans depend on these abilities, in particu-
results of the first imitations by minors had lar, the development the diversity of different
to be intensively socially controlled by parents occupations, as well as thinking in highly de-
and other community members, and the devel- veloped cultural communities.
oping minors had to repeat and rehearse the
imitated actions until they mastered the neces- Recording of laser evoked potentials dur-
sary level of precision. These activities were ing preferential stimulation of mechano-
then neuronally fixed for automatic future ap- insensitive nociceptors unmasked by pe-
plication. Apart from these activities, a gesticu- ripheral nerve block M. Dusch (1*), J. van
latory communication developed, perhaps out der Ham (1*), B. Weinkauf (1), J. Benrath (1),
of gestural pointing at or towards important ob- M. Schmelz (1), R. Rukwied (1), M. Ringkamp
jects or events. The gesticulatory communica- (2), R-D. Treede (3), U. Baumgärtner (3) (1)
tion incorporated primarily the language char- Dept. of Anaesthesiology, Medical Faculty
2012, 5 (1) Kognitive Neurophysiologie des Menschen 65
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
Mannheim, Heidelberg University, Germany; gional individuality indices and reliability
(2) Dept. of Neurosurgery, Johns Hopkins Uni- in complex cognition: FMRI and ERP-data
versity, Baltimore, Maryland; (3) Chair of Neu- Thorsten Fehr Center for Cognitive Sciences;
rophysiology, Centre for Biomedicine and Med- University of Bremen
ical Technology Mannheim, Medical Faculty Individual differences, but also the reliability
Mannheim, Heidelberg University, Germany of psychophysiological measurements are im-
In order to investigate preferentially mechano- portant upcoming topics in the neurosciences.
insensitive (MIA) nociceptors in healthy volun- Usually, experimental approaches are directed
teers, laser radiant heat stimuli were applied to to reduce information to describe neural cor-
the lateral proximal leg after peripheral nerve relates of complex mental processes in a
block of the lateral femoral cutaneous nerve more comprehensible and putatively sufficient
(LFCN). Laser-evoked potentials (LEP) were way. However, individual aspects potentially
recorded in healthy volunteers from partially due to individual learning history and mental
anesthetized skin areas. strategy run the risk of being inappropriately
Nerve block of the LFCN was performed in 10 neglected. Furthermore, retest-reliability in
healthy male subjects with Ropivacain 1 individual physiological parameters has not
In the area of differential sensitivity LEP re- been examined in both experimental intra-
sponses were delayed compared to unaffected and inter-session arrangements. The present
skin (225 ±10.4 ms (SEM), vs. 185 ±7.8 ms) approach utilizes the STROOP-paradigm as
and LEP amplitudes were reduced (13.8 ±1.3 one of the most consistent and reliable experi-
µV vs. 25.6 ±1.6 µV). Reaction times of pain mental procedures in psychological sciences.
responses to the laser stimuli were increased Based on previously published data, there was
(654 ms vs. 406 ms, p<0.01) and pain magni- an adapted form of the STROOP-task applied
tude reduced (1/10 vs. 5/10 NRS; p<0.01). in an EEG- and fMRI-study to estimate indi-
The increase of LEP latency suggests that vidual intra- and inter-session reliability of be-
mechano-insensitive heat-sensitive Aδ noci- havioural and physiological data. Behavioural
ceptors (MIA type II) have a slower conduction data showed the expected interference effect
velocity or a higher response latency as for incongruent as compared to congruent
compared to mechano-sensitive Aδ nocicep- and baseline conditions reflected in longer
tors (type II MSA). Alternatively, recruitment response times for the incongruent condition.
of widely branched slowly conducting and Different individuality indices on the basis of
mechano-insensitive branches of Aδ nocicep- Cartesian analytical geometric will be intro-
tors can explain our finding. We conclude duced and applied on functional neuroimaging
that recording of LEP during laser stimulation data. Reliability- and individuality-estimations
of areas with differentially anesthetized skin of ERP- and fMRI-data will be compared,
is useful to study a mechanically-insensitive, illustrated, and critically discussed.
heat-sensitive subpopulation of Aδ nocicep-
tors. Topographic correlates of semantic prim-
ing differentiate Alzheimer’s and semantic
Alternative approaches in estimating re- dementia M. Grieder (1), R.M. Crinelli (2), T.
66 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
Dierks (1), L.-O. Wahlund (2), T. Koenig (1), M. altered in AD and SD patients whereas the
Wirth (3) (1) Dept. of Psychiatric Neurophys- late controlled components are affected most
iology, University Hospital of Psychiatry, Uni- dominantly in the SD group. Taken together,
versity of Bern, Switzerland; (2) Karolinska In- these results could reflect that the semantic
stitute, Dept. NVS, Division of Clinical Geri- database itself is likely to remain preserved in
atrics, Stockholm, Sweden; (3) Jagustlab, He- AD and to a less extent also in SD patients,
len Willis Neuroscience Institute, University of who suffer from deteriorated retrieval of se-
California Berkeley, Berkeley, CA, USA mantic representations. Taken together, the
automatic spread of activation in the semantic
With the progressing course of Alzheimer’s network appeared to be preserved in both pa-
disease (AD), deficits in declarative memory tient groups, while the late ERP components
increasingly restrict the patients’ daily activi- gave a clear indication of neurophysiological
ties. Besides episodic memory impairments, alterations in AD and SD. Together with subse-
semantic memory is affected by this demen- quent studies, these novel findings might im-
tia subtype. In contrast, patients suffering from prove a profound understanding of the demen-
semantic dementia (SD) show isolated seman- tia subtypes and their early detection.
tic memory impairments. With the aim to es-
tablish sensitive biological markers for the dif- EEG recorded during gross-motor behav-
ferentiation of symptom dimensions in demen- ior and sleep Hoedlmoser, K. (1), Birklbauer,
tia subtypes, the present study compared AD J. (2), Rigler, S. (1), Mueller, E. (2), & Sch-
and SD patients with healthy controls. In par- abus, M. (1) (1) Laboratory for Sleep and Con-
ticular, the automatic and controlled seman- sciousness Research, Department of Psychol-
tic word processing was investigated by com- ogy, University of Salzburg, Austria; (2) De-
bining the recording of event related poten- partment of Sport Science and Kinesiology,
tials (ERP) with the performance of a seman- University of Salzburg, Austria
tic priming (SP) task. Concretely, the task re- There is now compelling evidence that sleep
quired word/non-word (prime and target) lexi- contributes to the consolidation of procedural
cal decisions on sequentially presented word types of memory and to motor learning in par-
pairs, consisting of semantically related or un- ticular. Concerning offline processing of fine-
related prime-target combinations. Besides motor skills during sleep there is already pro-
the analysis of the target onset reaction times found knowledge. However, data on gross-
(RT), early automatic and later controlled ERP motor tasks are still missing. Therefore, the
components were investigated. Both patient aim of our study was to investigate sleep ef-
groups showed general slowed RTs for all fects on performance in a real-life gross-motor
task conditions (related and unrelated word task: riding an inverse steering bicycle. We
pairs), whereby the SD performed consider- tested 20 healthy male subjects (20 - 29 yrs;
able slower than the AD. However, the size M=24.3, SD=2.03) by a between-subject de-
of the SP effect was comparable in all partic- sign. Each subject either participated in a 2hr
ipant groups. The ERP results indicate that midday nap or a restful wake condition. In both
early automatic components are only slightly conditions participants were previously trained
2012, 5 (1) Kognitive Neurophysiologie des Menschen 67
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
on the gross-motor learning task and tested for (2), Tobias Banaschewski (1), Martin Holt-
performance pre- and post-sleeping/resting. mann (1,6), Daniel Brandeis (1,7) (1) De-
Gross-motor performance was decreased af- partment of Child and Adolescent Psychiatry
ter nap but not after resting wakefulness. Fast and Psychotherapy, Central Institute of Men-
sleep spindle density (13-15Hz) was nega- tal Health; (2) Department of Psychiatry and
tively related to the change of performance Psychotherapy, CIMH; (3) Department Neu-
over nap, whereas slow sleep spindle density roimaging, CIMH; (4) Department of Clinical
(11-13Hz) was generally (baseline and exper- Psychology, CIMH; (5) Department of Cog-
imental nap) negatively related to initial gross- nitive and Clinical Neuroscience, CIMH; (6)
motor performance. Together these findings Department of Child and Adolescent Psychia-
suggest that fast sleep spindles during short try – University of Bochum; (7) Department of
midday naps interfere with gross-motor con- Child and Adolescent Psychiatry - University
solidation and individual’s general gross mo- of Zürich
tor learning ability is reflected in interindividual Recording EEG during an fMRI - session is
differences of slow sleep spindle activity. Ad- increasingly used to study cognitive and mo-
ditionally to our sleep-related hypotheses, we tivational states in basic and clinical neuro-
investigated EEG alpha activity during riding science. We used this combined measure-
the inverse in comparison to a normal steer- ment technique to learn more about the hu-
ing bicycle in a subsample of our subjects man reward system. Simultaneous recordings
(N=5). These analyses revealed a strong task require modifications of the original fMRI re-
related alpha synchronization more prominent ward task to improve signal to noise ratio for
during inverse compared to normal steering bi- EEG. One aim of the present study was thus
cycling. As the inverse steering bicycle pro- to find out whether the fMRI core results would
vides an inversion-evoked cognitive load due prove robust in the modified paradigm, while
to inhibition of highly automated movement resolving potential technical problems which
patterns (riding a normal steering bicycle), the may occur when combining both methods in
observed task related power increase in the al- challenging motivational paradigms. Based on
pha band with respect to a reference can be previous work of Kirsch et al. (2003) we modi-
considered as a cortical correlate of the inhibi- fied a reward anticipation task for the use with
tion of already well known, automated memory EEG, which is known to reliably activate ventral
traces. striatal brain structures. EEG data and fMRI
Recording EEG and fMRI simultaneously images were simultaneously acquired in a 3T
during a reward anticipation task: Pilot re- MRI Siemens TIM Trio scanner from 20 healthy
sults for a study with ADHD children Sarah participants (20 to 26 years) using an event re-
Hohmann (1), Michael Plichta (2), Isabella lated design. Money gained of the reward task
Wolf (1,3), Stefanie Rechtsteiner (1), Sarah was paid after the fMRI-Session.
Baumeister (1), Maria Zangl (5), Christine We found a stronger BOLD signal in the ven-
Niemeyer (4), Matthias Ruf (3), Peter Kirsch tral striatum during anticipation of reward. The
(4), Herta Flor (5), Andreas Meyer-Lindenberg robust activation of the brain reward system in
68 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
our modified monetary incentive task confirms aim of the current study was to examine the
that neither simultaneous fMRI-EEG, nor the effects of acute exercise before and after train-
corresponding task modifications diminished ing under normoxic versus hypoxic conditions
sensitivity in detecting ventral striatal BOLD- on Electroencephalography (EEG). Three en-
responses. The analyses revealed meaning- durance untrained male volunteers performed
ful ERPs with significant differences between one-legged cycle training for 30 minutes, three
both conditions (win money/no money) devel- times per week, for four weeks. One leg was
oping during early (<1s) as well as late (>1s) trained under normoxic and the other leg under
stages of reward anticipation. normobaric hypoxic (12.5Before training, up-
Showing that simultaneous combination of per alpha power increased by after normoxic
both methods produced good data quality but decreased by after hypoxic exercise in the
concerning electrophysiology and hemody- parietal region. These changes were attenu-
namic response future work will concentrate ated after training in normoxia but even more
on data fusion of both techniques to fully uti- pronounced after training in hypoxia. Our re-
lize the complementary information brought by sults suggest that exercise effects on EEG
EEG to fMRI and vice versa. In future studies are strongly influenced by hypoxia. Training-
with ADHD-children we will apply this task to induced adaptations to normoxic versus hy-
study effects of neurofeedback-training on the poxic exercise may have opposite directions
brain reward system regarding neurobiological however, with the same meaning (here: in-
and neurophysiological alterations. creased activity in the parietal cortex).
Acute and chronic response of electroen- Do lateralized readiness potentials help to
cephalographic activity to exercise during elucidate extraversion-related differences
normoxia and normobaric hypoxia: a pi- in the magnitude of the psychological re-
lot study Hülsdünker, T. (1), Gutmann, B. (1), fractory period (PRP) effect? Rebekka In-
Mierau, A. (1), Mierau, J. (1), Hollmann, W. dermühle, Stefan Troche, and Thomas Ramm-
(2), Strüder, H.K.(1) (1): Institute of Movement sayer Department of Psychology, University of
and Neurosciences, German Sport University Bern, Bern, Switzerland
(Cologne, Germany), (2): Institute for Cardiol- Psychological refractory period (PRP) refers
ogy and Sports Medicine, German Sport Uni- to a major bottleneck of information process-
versity (Cologne, Germany) ing that becomes evident when participants
It has been suggested, that exercise train- are required to respond to two signals (S1
ing under normobaric hypoxia may be supe- and S2) presented in rapid succession. Typi-
rior to normoxic training for the performance cally, the response to S2 becomes increasingly
of endurance athletes. So far, most of the delayed with decreasing stimulus onset asyn-
previous research has focused on vascular, chrony (SOA) between S1 and S2. The ma-
metabolic and muscular changes associated jor goal of the present study was to answer
with exercising under hypoxia without taking the question of whether extraversion-related
into account that changes may also occur in individual differences can be identified at this
the central nervous system. Therefore, the stage of premotor information processing. For
2012, 5 (1) Kognitive Neurophysiologie des Menschen 69
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
this purpose, 63 introverts and 63 extraverts which is prominent in the delta-band (0.5-3
performed a PRP task and stimulus-locked Hz), can be detected [1]. This delta compo-
(S-LRP) and response-locked (LRP-R) lateral- nent, by its functional and topographical simi-
ized readiness potential latencies were deter- larity to the P300, was interpreted as reflecting
mined. To quantify the PRP effect at the be- the conscious recognition of the perceptual
havioral level, regression analyses were per- change. However, focused attention needed
formed separately for each participant with during perceptual reversals should also reflect
SOA as independent variable and response in an enhanced theta (4-7 Hz) response. This
time to S2 as dependent variable. Thus, the EEG study aimed to investigate the reversal-
resulting regression coefficient b represents related delta and theta activity using the stro-
an estimate of the magnitude of the individ- boscopic alternative motion (SAM) paradigm,
ual PRP effect. While at the behavioral level, a multistable stimulus that during constant
a reliably more pronounced PRP effect could viewing induces internally generated changes
be confirmed for introverts compared to ex- in the perceived direction of motion of flashed
traverts, extraversion-related individual differ- dots. Reaction times from an unambiguous
ences could be revealed neither for S-LRP nor control condition were used to estimate the
for LRP-R latencies. Our findings suggest that stimulus onset after which the percept has
experimentally induced overload of the infor- presumably changed. Reversal-related delta
mation processing system by means of a PRP as well as theta EEG power was enhanced
task appears to differentially affect introverts when compared to a time period during which
and extraverts. LRP analyses, however, did the percept was stable. As expected, the
not prove to be sensitive for the identification theta response exhibited a frontal maximum.
of these behavioral differences at the electro- Further, the topography of the theta response
physiological level. observed following exogenously triggered
This work was supported by the Swiss Na- perceptual reversals differed from internally
tional Science Foundation (105314-120096). generated perceptual changes. These results
suggest that the state of enhanced attention
Enhancement of delta- and theta EEG may be reflected by reversal-related activity in
power during perception of visual ambigu- the delta and theta band. These emphasize
ous stimuli. Ksenia Khalaidovski, Christina the influence of top-down regulated processes
Schmiedt-Fehr, Canan Basar-Eroglu & Birgit upon multistable perception [2]. [1] C. Basar-
Mathes. Institute of Psychology and Cognition Eroglu et al. (1993), Int J Neurosci 73, 139-51
Research, University of Bremen, Grazer Str.4, [2] B. Mathes et al. (2006), Neurosci Lett 402,
D-28359 Bremen, Germany 145-49
Ambiguous patterns make up a well-known
class of visual phenomena in which one in- EEG-Analysis with Matrix-Wavelets A. Klein
variant stimulus pattern is perceived in two Physiologisches Institut, Aulweg 129, 35392
different, mutually exclusive ways. When sub- Gießen
jects indicate a perceptual reversal by pressing Scalar wavelet analysis of EEG-recordings
a button a reversal-related slow positive wave, poses a considerable problem due to the
70 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
amount of data produced. In particular, the seven female right handed youth athletes (M
resulting wavelet transforms are not obviously = 16.79, SD = 2.68) from the German shoot-
related to each other, and it would be very ing federation (DSB). While the experimen-
desirable if known or suspected relationships tal group (N = 11) received attentional train-
between channels could be modelled within ing based on scientifically substantiated re-
the transform itself, not necessitating any ad- search and augmented by hypnotherapeutic
ditional steps. This requirement is met by the elements, participants in the control group (N
Matrix-Wavelet-Transform which operates on = 9) engaged in progressive muscle relaxation.
vector-valued instead of scalar-valued signals Both cohorts received six 90 minute training
using matrix-valued wavelet functions, and sessions. A 64-channel EEG was used be-
which guarantees that any information con- fore and after the trainings were conducted to
tained in the original signal is still available for evaluate the efficacy of the attention training
analysis in the computed transform. measures. In each of them a competition was
The possibilities of this novel method, for ex- designed in which the pistol shooters were re-
ample the analysis of centroids of activity, di- quired to shoot 60 shots on a target in 90 min-
mensionality of the signal, and time-frequency utes. The shot release was determined with
centroids, are presented and compared with the help of an optical sensor fixed directly on
results that were obtained with more traditional the weapon. The sensor’s analyzing software
methods. enabled the differentiation between good and
bad shots based on an assessment of sev-
Neuronal correlates of focused attention eral shooting relevant criteria during the aiming
in pistol shooting sports Christoph Krein- process. In addition to also assessing the par-
bucher, Andrea Geipel, Denise Beckmann- ticipant’s overall shot outcome, an assessment
Waldenmayer & Jürgen Beckmann Institute of the athlete’s distractibility from the shoot-
of Sport Psychology, Technische Universität ing tasks was conducted by evaluating the ath-
München lete’s perception of subliminal stimuli. Self-
In shooting sports the last few seconds of the report questionnaires were also used to evalu-
shot preparation are crucial for a successful ate the participant’s level of attention.
shot outcome. It is not yet clear if certain fre-
quencies in different regions of the brain are Results from baseline measures of the brain
mandatory for achieving peak performance. waves revealed that an increase of theta ac-
Therefore, neuronal correlates of focused at- tivity in frontal areas is only present in bad
tention in sport pistol shooting ought to be re- shots. Thus, there is evidently an optimal level
searched further. Moreover, the investigation of the theta frequency range. In good shots,
should reveal whether an increase in focused there is a higher alpha activity in parietal re-
attention can be achieved through the imple- gions two seconds before shot release than in
mentation of sport specific attentional training bad shots. These findings indicate an inhibi-
and if there are also changes related to the tion of verbal and analytical processes while
cortical activity. trying to become highly focused before pulling
The participants included thirteen male and the trigger. Further calculations are needed to
2012, 5 (1) Kognitive Neurophysiologie des Menschen 71
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
assess the degree to which a change in brain tions Mierau, A. (1), Hülsdünker, T. (1),
activity occurs through the implementation of Mierau, J. (1), Hense, A. (2), Hense, J. (2),
the attention training and how this correlates Strüder, H.K. (1) (1) Institute of Movement
with behavioral states. and Neurosciences, German Sport Univer-
sity (Cologne, Germany); (2) Children’s Sport
Change detection enhances the P3 and School NRW (Cologne, Germany)
fronto-parietal delta response during delay-
dependent working memory B. Mathes (1,2), The effects of acute exercise on brain corti-
J. Schmiedt (1), C. Schmiedt-Fehr (1,2), C. cal activity have been reported in some pre-
Pantelis (3) & C. Basar-Eroglu (1,2) (1) Uni- vious studies however, only for adults. To
versity of Bremen, Institute of Psychology and the best of our knowledge, there have been
Cognition Research, Bremen, Germany, (2) no studies which investigate such effects in
Centre for Cognitive Science, Germany (3) pre-school children although this age-group
Melbourne Neuropsychiatry Centre, University is characterized by a particularly high plas-
of Melbourne, Melbourne, Australia ticity of the central nervous system. 8 male,
Both, recognition of previously encoded stim- pre-school children participated in the study
uli and change detection enhance the P3. The (5.6±0.5 yrs; 122.4±4.2 cm; 22.1±2.7 kg). In
current study contrasted these opposite influ- a balanced cross over design participants ei-
ences on the P3 using a delayed matching-to- ther completed an exercise session (EXE) of
sample task, which included requirements of 45 min or a control condition (CON) where
commonly used working memory as well as they were allowed to paint and/or to talk to
change detection tasks. Mean P3 amplitude their parents. The exercise session consisted
and delta activity was analysed from partic- in three out of five different movement games
ipants who classified probe stimuli as either (10 min each) that were introduced in a coun-
being identical or modified. The P3 ampli- terbalanced order and a soccer match (15
tudes were larger for modified than for identi- min) at the end of the session. Heart rate
cal probes, with both eliciting a larger P3 than (HR) was recorded continuously before, dur-
during encoding. Enhanced single-trial ampli- ing and after exercise as a measure of physi-
tude and trial-by-trial consistency of delta ac- cal demand. 15-20 min before (PRE) and af-
tivity contributed to the larger P3 for the mod- ter (POST) one minute resting EEG record-
ified probe. Fronto-parietal phase coherence ings were completed with the eyes closed
of delta activity was also more enhanced for and the eyes open in a counterbalanced or-
modified than for identical probes. The results der between subjects. EEG data was Fourier
indicate that the P3 reflects an adaptable pro- transformed to provide estimates for abso-
cess of attentional resource allocation to opti- lute power in eight frequency bands (delta to
mize memory-guided decision-making. gamma) based on the individual peak alpha
frequency and analyzed in four regions across
Brain oscillatory changes after acute ex- the scalp. Average HR during the exercise ses-
ercise in pre-school children during eyes- sion was 150.2±15.8 beats/min. Lower-1 al-
closed versus eyes-open resting condi- pha power was reduced for CON compared to
72 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
EXE (p<0.05) in the eyes open condition. Fur- Supported by the German Federal Research
thermore, beta1 and beta2 power were signifi- Council, Wi 1166/10-2.
cantly lower in the frontal cortex for EXE com-
pared to CON (p<0.001). The results of the Bimodal processing of audio-visual stim-
present study show that acute exercise can in- uli during face-to-face communication
duce significant changes in brain cortical ac- Horst M. Müller, Verena Winter, Hendrik
tivity of 5-year old children. These changes Wesselmeier SFB 673 „Alignment in Commu-
are characterized by decreased frontal activ- nication“ and EC 277 „Cognitive Interaction
ity accompanied by a reduction of global corti- Technology“ (CITEC), University of Bielefeld,
cal arousal however, only when visual input is 33501 Bielefeld, Germany
present. While speaking in a face-to-face dialogue, lip
reading supports the language comprehension
Statistical methods for the identification of process substantially. Besides this bimodal
significant directed interactions between binding process during natural language com-
EEG signals T. Milde, K. Schwab, L. Leistritz prehension, perception of voice and lip move-
& H. Witte Institut für Medizinische Statistik, In- ment of the interlocutor is not synchronic. In a
formatik und Dokumentation conversation, for instance standing two metres
The Granger Causality Index (GCI) and Par- apart from each other, an approx. 6 ms delay
tial Directed Coherence (PDC) are two of the of the voice exists. Due to this fact, auditory
most common methods for the identification of sensation after visual sensation is a common
directed interactions between EEG signals. To circumstance, but auditory sensation before vi-
identify statistically significant interactions it is sual sensation should be unusual to us. How-
necessary to know the probability distributions ever, in comparison to hearing only, an audio-
of these interaction measures under the null- visual signal should have the most ecological
hypothesis of absent interactions. As desired validity. In this study, we investigated 1) how
distributions are mostly unknown nonparamet- varying the temporal synchronity of the audi-
ric statistical methodologies must be used to tory signal to the visual signal evokes different
identify significant interactions. Fundamentals ERP wave forms and 2) how bimodal audio-
of GCI- and PDC-analysis are presented us- visual processing will influence the amplitude
ing multivariate AR-models. Statistical analy- of the N1/P2 component. Therefore, 25 sub-
sis of resulting values via bootstrapping in the jects perceived audio-visual sequences of up
multi-trial case and via surrogate data is pre- to four seconds in length. The auditory signal
sented. The focus is on the comparison be- laged for 0 ms, 40 ms, 80 ms, 200 ms, 360 ms
tween different groups and tasks. It can be and preceded 40 ms, 80 ms, 120 ms and 280
shown that topographic representations of sig- ms in relation to the visual signal while record-
nificant directed interactions allow conclusions ing the EEG. In addition, the bimodal effects
on interacting brain regions. Benefits of these were measured against a physical deviance
techniques are demonstrated for applications of the stimuli as an additional control condi-
in pain research and in clinical child psychol- tion. In a behavioral task the naturalness of
ogy. the stimuli was rated by a questionnaire and
2012, 5 (1) Kognitive Neurophysiologie des Menschen 73
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
compared to ERPs. The auditory after visual the first study was to compare the degree of
sensation caused flattened N1/P2 amplitudes overlap between both simulation states and
while the odd situation with auditory before vi- execution in one design. During fMRI mea-
sual sensation caused N1/P2 amplitudes sim- surement, participants had to imagine, ob-
ilar to natural synchronic stimuli. The results serve, and execute alternate, unilateral exten-
correlate with the findings from the behavioral sion/flexion movements with the right hand,
experiment where subjects had to judge when right foot, or both effectors simultaneously.
an audio-visually presented stimulus was out The fMRI results showed similarities between
of sync. These findings were discussed in execution and imagery in both the activation
the framework of the lip-moving requirements pattern and the dissociation of effectors in
of speaking humanoid robots, which could in- the contralateral motor cortex (M1, PMC &
crease the robustness of the machine to hu- SMA). Although these areas were activated
man communication. significantly during observation, this condition
Supported by the Deutsche Forschungsge- showed more of an overlap of both effectors. A
meinschaft (SFB 673, EC 277) somatotopic dissociation was found only in the
right (ipsilateral) hemisphere (BA44). To inves-
The Applicability of the Somatotopic Prin- tigate the relevance of somatotopy and move-
ciple to Action Execution, Imagery, and Ob- ment characteristics for the degree of overlap,
servation T. Naumann (1), B. Lorey (1,2), S. the second study extended the design to in-
Pilgramm (1,2), C. Petermann (4), M. Bischoff clude two additional movements. This time,
(1,2), K. Zentgraf (3,2), R. Stark (2), D. Vaitl participants had to imagine or observe three
(2) & J. Munzert (1) (1) Institute for Sports different unilateral movements executed with
Science, Justus Liebig University Giessen, D- either the right hand or the right foot. The first
35394, Germany; (2) Bender Institute of Neu- movement was the rhythmic extension/flexion
roimaging, Justus Liebig University Giessen, movement already described, the second was
D-35394, Germany; (3) Institute for Sports Sci- an accuracy-demanding pointing task, and in
ence, University of Bern, CH-3012, Switzer- the third task, subjects had to generate static
land; (4) Department of Sports Medicine, Jus- force by pushing a bellows. Results showed
tus Liebig University Giessen, D-35394, Ger- distinct activation sites in the contralateral mo-
many tor cortex for different movements during ac-
Jeannerod’s (2001) mental simulation theory tion observation. No clear somatotopic orga-
hypothesizes overlapping cerebral activation nization could be found for either hand or foot
during the imagery, observation, and execution movements. It is concluded that there might
of human movements. Several fMRI studies be a task-specific form of organization in ac-
have shown somatotopic activation patterns tion observation (Graziano, 2006), whereas an
for the imagery (Ehrsson et al., 2003) and effector-specific dissociation of different types
observation (Wheaton et al., 2004) of move- of movements is found for imagery.
ments with different effectors that are roughly
similar to the patterns found for their execu- Ehrsson, H. H. et al. (2003). Journal of Neu-
tion. Against this background, the goal of rophysiology, 90, 3304-3316. Graziano, M.
74 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
(2006). Annual Review of Neuroscience, 29, latencies pointing to deficits of MMN gener-
105-34 Jeannerod, M. (2001). Neuroimage, ation in depressed patients as opposed to
14, 103-109. Wheaton, K. J., et al. (2004). healthy controls. Brain source analysis sig-
Neuroimage, 22, 277-288. nificantly located the largest MMN impairment
in patients left frontally with increased latency.
Mismatch Negativity in Patients with Ma- However, despite full psychopathological re-
jor Depression Christine Norra (1), Sebas- sponse patients showed no significant change
tian Waniek (2) (1) Dept. of Psychiatry, Psy- of MMN after antidepressive pharmacother-
chotherapy, Preventive Medicine, Ruhr Univer- apy, irrespective of the selective nature of the
sity Bochum, (2) Dept. of Psychiatry and Psy- monoaminergic drug.
chotherapy, University Hospital Münster, Ger- Our findings point to deficits of the auditory in-
many formation processing in MMN in patients with
Mismatch negativity (MMN) is an auditory depressive disorder, too. However, the ab-
evoked potential that has consistently detected sence of any normalization of the MMN in the
neural pre-attentive information processing post-acute phase regardless of the pharma-
deficits of rare unexpected deviants mainly cological profile of monoaminergic antidepres-
in schizophrenia. Neurochemically the gluta- sants might rather refer to the trait character
matergic neurotransmitter system has been of underlying pathophysiological mechanisms
identified as crucial for the origin of deficits in depression. Further longitudinal studies are
in MMN. There is also some evidence for warranted to investigate the potential seroton-
monoaminergic modulation of MMN. Still, with ergic modulation of MMN and its clinical im-
regard to patients with depressive disorders pact.
there are only a few small and rather hetero-
geneous studies of MMN, so far. The aim Personal Identity from the Viewpoint of
of the study was first a comparison of MMN Neuroscience and (Analytical) Philosophy
between patients with major depression and a M. Ruchsow Christophsbad, Faurndauer Str.
healthy control group, and second, a longitudi- 6-28, 73035 Göppingen
nal examination of differential monoaminergic During the last years the controversy about di-
medication effects on MMN. achronic personal identity was dominated by
Auditory MMN was recorded using multi- naturalistic approaches, proposing a (modi-
channel EEG in 17 unmedicated inpatients fied) memory criterion (e.g. Locke), a physi-
with an acute depressive episode and age- cal criterion of bodily continuity (e.g. Williams,
matched healthy controls. Patients received Nagel), or a combination of both (e.g. Brand,
a follow-up MMN after four weeks of random- Northoff). Contrary to this, Wittgenstein’s non-
ized antidepressant treatment with selective naturalistic approach shows that the meaning
serotonergic or noradrenergic re-uptake in- of a word is its use in language (Philosophi-
hibitors. In parallel, depressed symptoms cal Investigations [PI] § 43). With reference
were documented on a weekly basis. to (diachronic) personal identity Wittgenstein
MMN amplitudes of scalp derived potentials succinctly remarks that „there is a great variety
were impaired, with different alterations in the of criteria for personal ’identity’“ (PI 404) which
2012, 5 (1) Kognitive Neurophysiologie des Menschen 75
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
can be characterized by family resemblance of these phenomena (which, by the way, can
(PI 66). A detailed elaboration of Wittgen- even appear in a similar way for the Fourier
stein’s basic idea can be found in the work transform); since they cannot be avoided in
of the Canadian philosopher Charles Taylor general, it is a good idea to be at least aware
who advocates that personal identity nowa- of their existence.
days is influenced by three traditions: 1.) a
disengaged atomistic individualism originating Cortical current density oscillations in the
mainly from the philosophy of Enlightenment, motor cortex are correlated with muscu-
2.) a romantic expressivism as alternative to lar activity during (sub-)maximal bike exer-
Enlightenment philosophy, and 3.) a traditional cise Stefan Schneider (1), David Rouffet (2),
theistic position. Taylor refuses disengaged Francois Billaut (2), Heiko K. Strüder (1) (1)
atomism. In his view persons obtain identity German Sport University Cologne, Institute of
by identification with their social institutions / Movement and Neurosciences, Germany; (2)
social roles, which alludes to Hegel’s concept Victoria University Melbourne, School of Sport
of ethical life (Sittlichkeit) and I. Berlin’s con- and Exercise Science, Australia
cept of positive freedom. The present paper Despite modern imaging techniques, assess-
argues for a view of personality in the tradi- ing and localizing changes in brain activity dur-
tion of hermeneutics and (post)analytical phi- ing whole body moderate and intensive ex-
losophy and refuses naturalistic and neurosci- ercise is still challenging and has not been
entific solutions to the problem of diachronic shown so far. Using an active EEG system
personal identity. in combinations with source localization algo-
rithms, in this study we aimed to asses, dis-
Wavelets - what works and what doesn’t? T. play and localize changes in brain cortical ac-
Sauer Lehrstuhl für Numerische Mathematik, tivity at different intensities of bike exercise.
Heinrich-Buff-Ring 44, 35392 Gießen, Ger- Two experienced bikers (one male / one fe-
many male) served as subjects in this study. EEG
Wavelets are an extremely powerful tool to pro- activity was recorded on 32 sites across the
cess phenomena that are local in time and fre- motor cortex (m1). Simultaneously muscle ac-
quency. Such effects appear frequently espe- tivity was recorded using EMG. Muscular as
cially in the context of EEG signals. Due to well as brain activity were time locked to the
this reason, wavelet methods, discrete ones as pedaling cycle. Averaging 100 cycles at differ-
well as continuous ones, can be found in more ent Watt loads up tp 7W/kg body weight, re-
and more toolboxes for biosignal processing. vealed a high correlation between oscillations
In practice, however, it happens quite often in muscular activity and cortical current den-
that a transform is applied to a class of sig- sity (CCD) in the lower limbs motor cortex area
nals for which it is neither intended nor suit- (MNI 0/-40/60). Results demonstrate that it
able. This can lead to very strange results and is possible to assess and localize brain corti-
the reasons for that are of principal nature, not cal activity even during maximal exercise inten-
even due to incorrect or poor implementations. sity using highly sophisticated but also easy to
In this talk I will mention and explain some use and simple techniques like EEG in com-
76 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
bination with source localization algorithms. ther definite articles (leading to more coherent
Furthermore results confirmed the assumption discourse) or indefinite articles (leading to less
that increasing exercise intensity is accompa- coherent discourse) as well as a sequence of
nied by an increase in cortical current density meaningless letter combinations as a control
in M1, whereas activity patterns remain com- condition. Neurophysiological data revealed
paratively stable across different exercise in- condition related differences in brain activa-
tensities. tion patterns for both tasks. More precisely,
a combined consideration of electrophysio-
Multimodal imaging of complex language logical and vascular data gave insight to the
processing - A combined NIRS-EEG study complex neurocognitive processes underly-
S. Schneider (1), L. Wagels (2), A-C. Ehlis (1), ing pragmatic language comprehension. Our
L. Ernst, A.J. Fallgatter (1), A. M. Rapp (1) (1) results demonstrate the utility of combined
Clinic of Psychiatry und Psychotherapy, Uni- EEG and NIRS measurements to investigate
versity of Tuebingen, 72076 Tuebingen, Ger- neural substrates of higher-level cognitive pro-
many; (2) Department of Clinical Psychology cesses such as figural language processing
and Psychotherapy, University of Tuebingen, and discourse comprehension.
72072 Tuebingen, Germany
Modern neuroimaging methods allow for a Are effects of sleep deprivation treatment
distinct visualization of the localization, func- in patients with major depression pre-
tion and intercommunication of the language dictable by event-correlated potentials?
network. The deliberate, combined application Streuer M, Son K, Juckel G, Norra C Dept.
of different imaging methods, in particular, of Psychiatry, Psychotherapy and Preventive
can benefit a holistic investigation of dynamic Medicine, LWL University Hospital Bochum,
processes, on the one hand, and brain regions Ruhr University Bochum, Germany
and networks, on the other, that are crucially As opposed to psychopharmacotherapy the
involved in language processing. The present antidepressive effect of sleep deprivation is
study focuses on simultaneous recordings immediate and clinically striking. However,
of electroencephalography (EEG) and near- the search for neurobiological predictors like
infrared spectroscopy (NIRS) to investigate aminergic-cholinergic dysbalance of REM
both temporal as well as topographical as- sleep, alterations of circadian rhythms, effects
pects of brain activation patterns associated of vigilance or microsleep has not yet been
with the processing of complex language, such successfully terminated. The loudness depen-
as metaphorical speech or coherent discourse. dence of auditory evoked potentials (LDAEP)
A group of 20 right-handed, healthy subjects has been found a potentially valid psychobi-
performed two subsequent tasks while EEG ological marker for the serotonergic system.
and NIRS data were recorded simultaneously: Therefore, the influence of sleep deprivation
First, participants had to judge the mean- treatment on LDAEP in depressive patients
ingfulness of metaphoric, literal or nonsense was examined in a controlled study.
phrases. In the second paradigm short stories In 27 inpatients with a moderate to se-
were presented in form of sentences with ei- vere episode of major depression taking
2012, 5 (1) Kognitive Neurophysiologie des Menschen 77
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
their individual antidepressive medication a processing of compatible and non-compatible
multichannel-EEG was recorded on two con- color words (Stroop condition) and simple
secutive mornings. Auditory evoked potentials color words (Color condition). Two groups
with different intensities (60-100 dB) were of 22 healthy adults each participated in two
recorded, and LDAEP of N1 and P2 ampli- different experiments. In the Stroop condition
tudes was determined. 14 patients took part in compatible and incompatible color words were
supervised sleep deprivation while 13 patients presented on a monitor while in the Color con-
served as controls by sleeping as usual. In dition simple color words appeared. EEG was
addition, mood (BDI, HAM-D) and sleepiness recorded from 30 channels between the inion
(SSS) was psychometrically assessed. and 5In the Stroop condition effects of stimu-
Self- and investigator-rated assessments lus compatibility were seen with components
showed significant improvement of depres- between 120 und 170 ms where compatible
sive mood in depressive patients after SD stimuli yielded significantly larger responses.
compared to controls. AEP amplitudes and la- In the Color condition global field power was
tencies were not different between the groups, significantly smaller than in the Stroop con-
and LDAEP remained intra-individually stable. dition. Components occurring at 170 and at
Still, there was a clear tendency (p<0.069) of 200 ms showed significant differences in their
a stronger LDAEP at baseline in responders scalp topography. There were no topograph-
to SD compared to non-responders. ical differences at latencies smaller than 130
Altogether this pilot study showed effects ms. Our results illustrate that the compatibil-
of sleep deprivation in AEP analyses of ity of Stroop stimuli is reflected early in field
subgroups with stronger LDAEP, i.e., lower strength and topography at about 120 ms la-
serotonergic activity, in depressive patients tency. In addition, components occurring after
who were responders to SD. The results are 170 ms activated different neurons in Stroop
in line with previous studies showing that a and Color condition. This suggests specific
stronger LDAEP seems to be associated with top-down processing at the level of the visual
a favourable treatment response to seroton- cortex.
ergic antidepressants, e.g., SSRI. In order
to find the optimum indication for SD among Topographical Correlates of Human Se-
depressive patients further studies of LDAEP mantic Learning W. Skrandies (1) & H.
in SD are warranted in larger patient samples. Shinoda (2) (1) Institute of Physiology, Justus
Liebig University, Giessen, Germany; (2) Fac-
Scalp Topography Evoked by Reading ulty of Psychology, Rissho University, Tokyo,
Color Words W. Skrandies Institute of Physi- Japan
ology, Justus Liebig University, Giessen We studied human semantic learning of Kanji
Brain imaging studies show that non- symbols in 18 healthy German adults. Forty
compatible Stroop stimuli activate the an- Kanji characters were presented visually in
terior cingulum of the human brain, and random order before and after a learning ses-
commonly late ERP effects are described. In sion of 20 minutes duration. In the learning
an electrophysiological study we analyzed the period subjects acquired the meaning of 20 of
78 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
the stimuli while the other stimuli served as coupling indices have been investigated in the
unlearned control condition. Learning perfor- alpha range (8-12 Hz) for the reproduction and
mance was tested at the end of the experi- recognition conditions as well as for a resting
ment. Event-related potentials were recorded condition. No significant differences in alpha
from 30 electrodes between the inion and power (8-12 Hz) between the retention inter-
Fz, and were averaged offline for each con- vals of recognition or reproduction and a rest-
dition separately. All subjects learned stimu- ing condition have been observed. However,
lus meaning with a recall rate of more than in contrast to a resting condition, phase de-
90Our findings show that learning of the se- coupling of a distributed network in the Alpha
mantic meaning of Kanji characters occurs range (8-10 Hz) could be found for both condi-
rapidly within 20 minutes. Learning is directly tions. Further phase coupling analysis showed
related to neurophysiological changes at early significant coupling mechanisms in the upper
processing stages. Thus learning is reflected Alpha (10-12Hz) in the reproduction condition
by systematic changes in scalp topography of between left dorsolateral premotor cortex, right
electrical brain activity of primary visual areas. primary motor cortex and right central and
centroparietal regions in the last second of
Phase Locking Mechanisms in the Alpha the retention period. While Alpha power did
Range During Retention of a Motor or Vi- not play a major role retaining a motor mem-
suospatial Working Memory Trace E. Weber ory trace, phase coupling analysis uncovered
(1), B. Griesmayr (1), & P. Sauseng (2) (1) De- memory-relevant network couplings. This cou-
partment of Physiological Psychology, Univer- pling mechanism may be interpreted as a mo-
sity of Salzburg, A-5020, Salzburg, Austria tor memory trace which is relevant for the re-
The neuronal correlates of retaining a motor call of the respective motor response in par-
memory trace are examined in 30 healthy par- ticular shortly before the execution of the ini-
ticipants. Studies using transcranial magnetic tially inhibited motor response. Supported by
stimulation (Hummel et al, 2002, Sauseng et the FWF Project P 22084
al., 2009) showed decreased cortical excitabil-
ity while alpha amplitude was high. Thus, al- Reliability of ERP-data in the STROOP in-
pha activity is assumed to be important for terference task Juliana Wiechert Department
response inhibition. Concerning interregional of Neuropsychology and Behavioral Neurobi-
connectivity, Serrien et al. (2005) found in- ology, Universität Bremen
creased connectivity between the sensorimo- The STROOP-paradigm is one of the most
tor cortex and prefrontal cortex shortly after consistent experimental approaches in psy-
presentation of NoGo stimuli. In the presented chological sciences. However, retest-reliability
experiment, a finger sequence had to be en- in individual physiological parameters has not
coded and reproduced after a retention inter- been examined in both experimental intra- and
val of three seconds. In a control condition, inter-session arrangements. Based on previ-
the finger sequence only had to be recognized ously published data, an adapted form of the
(but not reproduced) after the retention inter- STROOP-task was applied in an EEG-study
val. In this study, power changes and phase to estimate individual intra- and inter-session
2012, 5 (1) Kognitive Neurophysiologie des Menschen 79
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
reliability of behavioural and electrophysiologi- and frequency-frequency couplings). In a first
cal data. Preliminary behavioural data showed step the parameters of the coupled differential
both consistent split-half as well as re-test re- equations (oscillators) are estimated by using
liability in 15 healthy young female study par- the measured EEG data. In a second step
ticipants. There was an expected interference the differential equations are solved which
effect in the incongruent condition reflected results in a corresponding modeled EEG real-
in longer response times compared to both ization. The comparative time-variant analysis
congruent and baseline conditions, and a fa- between measured and simulated data re-
cilitation effect in the congruent condition re- veals the effects which can be explained by
flected in shorter response times compared the model. Such strategies were successfully
to the baseline condition. Electrophysiolog- applied for analysis of EEG burst patterns
ical data suggest larger intra- as compared in sedated patients (encephalographic burst
to inter-session-reliability. Topographical ERP- suppression pattern) and in healthy neonates
effects appeared to be less reliable at process- (burst-interburst patterns during quiet sleep)
ing relevant electrode sites across sessions and can be adapted on other oscillatory
as compared to electrode positions not pre- EEG/MEG activities.
senting any condition differences. Behavioural
data will critically be discussed in relation to Neural correlates of switching the atten-
the respective electrophysiological findings in tional focus during finger movements
an extended sample of individuals. Kristin Marie Zimmermann (1,2), Matthias
Bischoff (2), Britta Lorey (2,3), Rudolf Stark
Model-based strategies for time-variant (2), Joern Munzert (3) & Karen Zentgraf (1,2)
analysis of oscillatory EEG/MEG activity H. (1) Institute of Sport Science, Department of
Witte, Th. Lehmann, M. Wacker, L. Leistritz Human Performance and Training in Sport,
Institute of Medical Statistics, Computer Sci- University of Muenster, Muenster, Germany;
ences and Documentation, Jena University (2) Bender Institute of Neuroimaging, Justus
Hospital, Friedrich Schiller University Jena, Liebig University, Giessen, Germany; (3) In-
D-07740 Jena stitute of Sport Science, Department of Sport
It is shown that model-based analysis strate- Psychology, Justus Liebig University, Giessen,
gies can be beneficially used for exploring Germany
phase coupling characteristics (linear and For more than a decade, sports-related re-
non-linear) and cross-frequency couplings search has been concerned with the effects of
of and between EEG oscillations. As model various attentional strategies on motor perfor-
coupled non-linear oscillators (e.g. of the mance. Thereby comparing an attentional fo-
Duffing type) were applied to identify the cus on moving body parts (internal focus) with
dependencies between time-variant phase- a focus directed on extracorporeal movement
locking, n:m synchronization, and quadratic effects (external focus), the latter seems supe-
phase coupling patterns as well as their rela- rior in producing a benefit in performance out-
tions to so-called cross-frequency couplings come. However, the search for differences in
(amplitude-amplitude, amplitude-frequency the underlying mechanisms of an internal and
80 Human Cognitive Neurophysiology 2012, 5 (1)
W. Skrandies — Abstracts of the 20th German EEG/EP Mapping Meeting
an external attentional focus during motor ex-
ecution has just started. This study investi-
gated the effects of switching from a trained to
an unfamiliar attentional focus on BOLD sig-
nal change by applying functional magnetic
resonance imaging (fMRI). While performing
an overlearned finger tapping sequence (80
correct sequence executions prior to scanner
session), participants (M = 24.7 years; SD =
2.9; gender matched) were instructed to ei-
ther attend to the keys of the response box
(external focus) or to their fingers (internal fo-
cus). For the last half of all trials during scan-
ner session, an unexpected change in atten-
tional focus (from external to internal and vice
versa) was verbally instructed. The instructed
attentional switch led to increased responses
in the inferior frontal gyrus and the inferior
and superior parietal lobule, assumed to de-
pict attentional reallocation. Moreover, chang-
ing from a trained external to a novel inter-
nal focus was associated with higher activation
in the left primary somatosensory cortex and
the right posterior cerebellum. When switch-
ing from a trained internal to an unfamiliar ex-
ternal focus, increased activation was found in
the left premotor cortex, the left secondary so-
matosensory cortex, bilateral anterior and pos-
terior cerebellum, the vermis and the basal
ganglia. We suggest that the motor-related ar-
eas recruited when switching to an external fo-
cus of attention are reflecting a beneficial alter-
ation in motor processing by enhancement of
sensorimotor integration.
2012, 5 (1) Kognitive Neurophysiologie des Menschen 81
Book Review – Buchbesprechung
M. Doppelmayr – Übersicht zeigt zugleich den umfassenden
Neurobiologie der und multidisziplinären Ansatz, der keinen der
in diesem Feld notwendigen oder relevanten
Psychotherapie Wissenschaftssektoren ausspart.
(Buchbesprechung) Für den Großteil der Leserinnen und Leser
werden vermutlich diejenigen Kapitel, die
M. Doppelmayr, FB Psychologie, Universität einen ganz klaren Bezug zu psychischen
Salzburg, Hellbrunnerstr. 345020 Salzburg, Funktionen, sozialen Prozessen oder psychis-
Austria chen Störungen haben, die Wichtigsten sein.
Michael.Doppelmayr@sbg.ac.at Dieser Bereich umfasst etwas mehr als die
Hälfte des Buches und schließt eine Vielzahl
an Themengebieten und Störungsbilder ein.
In der zweiten Auflage des Buches Neurobi- Die einzelnen Kapitel präsentieren sehr
ologie der Psychotherapie verfolgt Prof. Dr. pointiert den aktuellen Stand der Forschung
G. Schiepek von der Paracelsus Medizinis- und sind fast ausnahmslos sehr gut und ver-
chen Universität Salzburg ein ausgesprochen ständlich geschrieben und mit entsprechen-
schwieriges und umfangreiches Unterfan- den Tabellen oder Graphiken aufbereitet. Die
gen. In diesem ca. 700 seitigen Sammelw- hohe Relevanz der neurobiologischen Grund-
erk werden so gut wie alle neurobiologisch lagen und Erklärungsmodelle für den Bereich
orientierten Aspekte der Psychotherapie der Psychotherapie wird hier klar demonstriert
aufgegriffen und zumeist detailliert disku- und abgebildet. In vielen der Kapitel wird auch
tiert. Knapp 100 Autorinnen und Autoren ganz spezifisch auf die jeweils ableitbaren
haben zu diesem Werk beigetragen, unter praktischen Konsequenzen der vorgelegten
Ihnen Persönlichkeiten wie T. Banaschewski, Befunde hingewiesen. Abhängig vom jew-
N. Birbaumer, H. Flor, H. Haken, U. Halsband, eiligen Autor werden naturgemäß die Grund-
T. Kircher, W. Leeb, H. Markowitsch, W. Milt- lagen und Befunde in sehr unterschiedlicher
ner, V. Müller, W. Singer oder P. Tass, um nur Tiefe und aus unterschiedlichen Blickwinkeln
einige zu nennen. präsentiert. In seiner Gesamtheit ist dieser
Nach einem einleitenden umfassenden Teil aber ausgesprochen gut elaboriert, aktuell
Überblick werden die unterschiedlichen Betra- und zumeist hervorragend aufbereitet.
chtungsweisen in acht Themenschwerpunkten Neben dem eben beschrieben Teil gibt es
aufgearbeitet. Die Themen erstrecken sich hi- noch viele weitere Kapitel, die vornehmlich
erbei auf die Gebiete Messmethoden; Moleku- Methoden oder reine Grundlagen präsen-
lare Neurobiologie von Gehirn, Immun- und tieren. Wenngleich auch diese gut aufbereitet
Endokrinsystem; Das Gehirn als komplexes sind, aktuelle Verfahren und neue Entwicklun-
System; Psychische Funktionen; Neurobiolo- gen aufzeigen, so erscheinen mir diese vom
gie sozialer Prozesse; Psychische Störungen; Umfang her etwas unpassend. Für Fachleute
Konsequenzen für Therapien; Wissenschaft- bieten diese kaum Neues und für Personen
stheoretische und ethische Fragen. Diese die sich nicht konkret damit beschäftigen
82 Human Cognitive Neurophysiology 2012, 5 (1)
Book Review – Buchbesprechung
erscheint es zu detailliert. Außerdem ist
etwas unglücklich, wenn z.B.: im Kapitel
zur Elektroenzephalographie spezielle Be-
funde zu Alzheimer Demenz, Depression oder
Schizophrenie besprochen werden, die man
in dieser Form in den spezifischen Kapiteln zu
den Störungen so nicht mehr findet und somit
übersieht, wenn man die Methodenkapitel
nicht durcharbeitet.
Zusammenfassend lässt sich sagen, dass
dieses Buch eine von erstklassigen Autoren
verfasste, gut gewählte, ausgewogene und
inhaltlich sehr breite Palette an Wissen bi-
etet. Die Kapitel sind Großteils unabhängig
und bauen nicht direkt aufeinander auf, was
es ermöglicht beliebige Bereiche selektiv
durchzuarbeiten. Die Methoden und Grund-
lagen nehmen aus meiner Sicht einen etwas
zu breiten Raum ein, der besser für eine
vertiefte Aufarbeitung klassischer Störungs-
bilder genutzt werden hätte könnte. So sind
etwa dem klassischen Themenbereich ”De-
pression” gerade sieben Seiten gewidmet,
während Bereiche wie ”Systhemtheorie und
Dynamic Causal Modelling” mehr als 30
Seiten umfasst. Generell aber ist dieses
Buch eine hervorragende Arbeit, die sowohl
TherapeutInnen, neurobiologisch orientierten
Fachkräften als auch sehr interessierte Laien
faszinieren wird und mit der G. Schiepek eine
hilfreiche Brücke zwischen Neurobiologie und
Psychotherapie schlägt.
Neurobiologie der Psychotherapie, Günter
Schiepek; 2. Auflage; Schattauer Verlag, Stuttgart
(2011), ISBN 978-3-7945-2674-1, 704 Seiten, 224
Abbildungen, 32 Tabellen, EUR 119.-
2012, 5 (1) Kognitive Neurophysiologie des Menschen 83
Announcements — Ankündigungen
Announcements — Ankündigungen
• ISBET Meeting
The annual meeting of the International Society for Brain Electromagnetic Topography (ISBET) will
take place in Bristol, Tennessee, USA, as a Joint Meeting of ECNS - ISNIP - ISBET - EPIC from
September 12-16, 2012.
Information and Registration at: http://www.ecnsweb.com/2012-conference.htm
• 21. Deutsches EEG/EP Mapping Meeting / 21th German EEG/EP Mapping Meeting
Conference language is German; English contributions will be accepted.
– 12. bis 14. Oktober 2012; Schloss Rauischholzhausen
– Schwerpunkte / Themen
* M. Falkenstein (Dortmund) ”Altern, Kognition und Elektrophysiologie”
* Dr. M. Plichta (Mannheim) Symposium über ”NIRS - Grundlagen und Anwendun-
gen in der Neurophysiologie des Menschen”
– Anmeldeschluss ist der 15. Juli 2012.
– Information und Anmeldung unter: http://www.med.uni-giessen.de/physio/
84 Human Cognitive Neurophysiology 2012, 5 (1)