Different mental imagery abilities result in different regional cerebral blood flow activation patterns during cognitive tasks.

Using regional cerebral blood flow (rCBF) imaging, two populations having high and low imagery abilities were compared at rest and while performing two cognitive tasks: silent verb conjugation and mental imagery. The imagery task produced an rCBF increase in the left visual association and left frontal cortices in both groups. Differences between high and low imagers were observed on global and regional flow responses to cognitive tasks: low imagers showed a whole cortex CBF increase during both tasks; high imagers showed a right dominance in the visual association cortex in all conditions, and in the parietal association cortex at rest.