Creativity and the brain : an investigation of the neural correlates of creative thinking
Creativity is a complex construct involving several different mental operations. Neurophysiological studies on creativity have seldom fully considered this fact and have instead approached creativity as a single entity. Furthermore, most neurophysiological studies of creativity face methodological problems. The present studies follow a novel ... approach to investigate the neural underpinnings of creativity by focusing on one creative mental operation, namely conceptual expansion. Conceptual expansion refers to the ability to widen the conceptual structures of acquired concepts, a vital process in the formation of new ideas. This process can happen as a result of active contemplation, such as when individuals generate something novel or as a result of passive induction, such as when individuals try to comprehend and integrate something novel that they have not encountered before. Avoiding drawbacks from previous neurophysiological studies, the new approach introduced in the present work borrows from psycholinguistic research on novel metaphor processing to generate a passive conceptual expansion task. Two studies using functional magnetic resonance imaging (fMRI) and event related potentials (ERP) were carried out, assessing participants brain activity while they read novel metaphoric, senseless and literal sentences. Participants responses regarding the unusualness and appropriateness (the two defining characteristics of creativity) of the sentences served to categorize each trial into three subject-determined conditions: creative (high unusual and high appropriate), nonsensical (high unusual and low appropriate), and literal (low usual and low appropriate). Sentences regarded as creative were of special interest because they are thought to induce conceptual expansion passively in participants. The results of the fMRI study pointed to the involvement of a fronto-temporal network in the processing of conceptual expansion. Activations in the anterior inferior frontal gyrus and the frontopolar regions in the processing of both novel and appropriate stimuli reflect an increased effort to retrieve semantic information and greater semantic selection and integration demands from temporal lobe areas where semantic information is stored. The findings of the ERP study revealed an N400 modulation with regard to the unusual and appropriate (creative) as well as the unusual and inappropriate stimuli (senseless), again reflecting greater effort for semantic retrieval and integration. Together, such findings allow us to move closer to the finer mechanisms underlying creative thinking which is imperative in order to truly understand what creative thinking entails.