[Effect of time of day related mood changes on psychological performance].

40 inpatients suffering from endogenous depression were investigated by tests of mental abilities, one time in the morning and one time in the afternoon. The score of the verbal retention test and the score of the numerical test increased significantly from the morning to the afternoon, whereas the variables of concentration were not modified significantly. The depression scores and the intenseness of the mental deficits correlated significantly at any time, but there was no correlation between the improvement of mood and the increase of the achievement scores from the morning to the afternoon.