Mood congruence effect in explicit and implicit memory tasks: A comparison between depressed patients, schizophrenic patients and controls

This study investigates mood congruence effect in explicit and implicit memory tasks in 23 inpatients fulfilling DSM-III-R criteria for major depressive disorder. Performances were compared to those of 15 in- or outpatients fulfilling DSM-III-R criteria for schizophrenia, and 37 normal subjects serving as euthymics controls. All subjects were submitted to a standard cued recall test and to a word stem completion test devised to assess the effect of the initial presentation without the explicit retrieval of the words being necessary. The material used for these two tasks consisted of emotionally negative and positive words. The results show a mood congruence effect in the implicit memory task (and not in the explicit memory task) only in patients who had recovered from their major depressive episode (and not in depressed patients, schizophrenic patients, or controls). These results suggest that implicit and explicit emotional information processing differ from one another in certain respects.