S.G. Shamay-Tsoorya,∗, N. Adlera, J. Aharon-Peretzb, D. Perrya, N. Mayselessa a Department of Psychology, University of Haifa, Haifa 31905, Israel b Rambam Medical Center, P.O. Box 9602, Haifa 31096, Israel
A b s t r a c t
Although creativity has been related to prefrontal activity, recent neurological case studies postulate that patients who have left frontal and temporal degeneration involving deterioration of language abilities may actually develop de novo artistic abilities. In this study, we propose a neural and cognitive model according to which a balance between the two hemispheres affects a major aspect of creative cognition, namely, originality. In order to examine the neural basis of originality, that is, the ability to produce statistically infrequent ideas, patients with localized lesions in the medial prefrontal cortex (mPFC), inferior frontal gyrus (IFG), and posterior parietal and temporal cortex (PC), were assessed by two tasks involving divergent thinking and originality. Results indicate that lesions in the mPFC involved the most profound impairment in originality. Furthermore, precise anatomical mapping of lesions indicated that while the extent of lesion in the right mPFC was associated with impaired originality, lesions in the left PC were associated with somewhat elevated levels of originality. A positive correlation between creativity scores and left PC lesions indicated that the larger the lesion is in this area the greater the originality. On the other hand, a negative correlation was observed between originality scores and lesions in the right mPFC. It is concluded that the right mPFC is part of a right fronto-parietal network which is responsible for producing original ideas. It is possible that more linear cognitive processing such as language, mediated by left hemisphere structures interferes with creative cognition. Therefore, lesions in the left hemisphere may be associated with elevated levels of originality.
Although creativity is a central cognitive component which allows everyday flexible and adaptive behavior, there are few neurocognitive models of creative cognition. Creativity has been defined as the ability to produce responses which are both novel (i.e., original, rare and unexpected) and appropriate (i.e., adaptive and useful according to the task constrains) (Sternberg & Lubart, 1999). As opposed to convergent thinking, which is directed towards finding a single correct solution to a problem, creativity or divergent thinking involves the ability to consciously generate new ideas that branch out and allow for many possible solutions to a given problem. Several cognitive tests of divergent thinking have been used to assess levels of creative cognition (Guilford, 1956). Divergent thinking tests are instruments that have been designed to be open-ended and afford multiple appropriate responses such as ‘list as many alternate uses as possible for a shoe’ (Guilford, 1986). These tests provide structured and objective measurements of creativity and its components. One central component of creative cognition and divergent thinking is originality (Sternberg & Lubart, 1999). An idea is considered to be original when it is statistically rare and represents an uncommon unique response (Guilford, 1956, 1959, 1960, 1986). It is important to note here, that rare and unexpected ideas which are inappropriate are not considered original in divergent thinking tasks (Mackinnon, 1965; Runco & Charles, 1993). While recent experimental reports of creative cognition have included neuroanatomical measurements, originality has been investigated only in a handful of studies.