On the personality, neurobiology, and cognition of creativity

Two extreme groups of healthy male undergraduate students, either highly (n=12) or low creative (n=12), were pre-selected from a larger cohort (N= 60) by way of the Creative functioning test (Smith and Carlsson, 1990). The two groups underwent measurements of cerebral blood flow (CBF). CBF was measured first during rest and during three verbal tasks (random order): Automatic speech (Auto), word fluency (FAS) and the unusual uses of objects test (Brick). The participant answered state and trait anxiety inventories after the CBF measurements. On another day, intelligence tests and a test of defense mechanisms were administered.
Calculations were made of differences in blood flow levels between the FAS and the Brick measurements in the anterior prefrontal, fronto-temporal and superior frontal regions. In accordance with pre- diction, repeated measures-ANOVAs showed that the groups differed significantly in all three regions. The highly creative group had increases, or unchanged activity, while the low creative group had mainly decreases. The highly creative group also had higher hemispheric CBF means during rest compared to the low creative group.
The highly creative group had higher trait anxiety than the low creative group. On the intelligence tests the low creative group was superior both on logical-inductive ability and on perceptual speed, while the groups were equal on verbal and spatial tests. Logical ability was negatively correlated with anxiety.
Furthermore, the highly creative group had higher defensive variation than the low group. High defensive variability was positively correlated to the creativity test.
The results are discussed in terms of flexible interaction between complementary functions in the two hemispheres.