On frontal lobe functions: psychiatric patient controls.

Summary The Wisconsin Card Sorting Test was administered to 244 psychiatric patients (including 91 schizophrenics); and their test scores were compared with those from a group of 25 patients with operations on the dorsolateral frontal lobe. The frontal lobe patients were reliably inferior to the psychiatric patients in their card sorting performance. Analyses showed that factors of age, sex, and general intelligence cannot account for the difference. It is concluded that these results add further confirmation to Milner's suggestion that inferior performance on the Wisconsin Card Sorting Test reflects a specific deficit in patients with damage to the dorsolateral frontal lobes.