Impaired effortful cognition in depression.

Depressed patients have been reported to have deficits in "effortful," but not effortless, cognitive functions compared to healthy volunteers. To test the hypothesis that the effortful cognitive deficits in major depression are not simply a function of psychiatric illness or hospitalization, we administered both effort-demanding and effortless cognitive tasks to 17 inpatients with major affective disorder and 17 hospitalized psychiatric controls. The depressed patients performed significantly more poorly than the controls on the effort-demanding task. The groups did not differ on the effortless task. These findings suggest that depressed patients are impaired in performing effort-demanding cognitive tasks compared to nondepressed psychiatric patients.