A verbal and a visuospatial recall task were compared for discriminating power, using the matched-tasks methodology. These tasks were administered to long-hospitalized schizophrenics. No evidence of a differential deficit, that is, better recall of either the verbal or the visuospatial materials, emerged in the patients. The results replicate a former finding showing no difference between verbal and visuospatial recall in schizophrenics, using memory tasks which were less sensitive as left- and right-hemisphere measures and a non-verbal task less affected by verbal mediation. This replication questions the assumption that the hemispheric differences observed in schizophrenics affect such memory tasks.

This study uses matched-tasks methodology in order to test memory function in depressed and euthymic patients with major affective disorder. Neither drug-free depressed patients nor lithium-treated euthymic patients show a differential deficit in verbal versus non-verbal recall. However, while euthymic patients show no memory impairment, drug-free depressives do show poor memory functioning. The results support the view that memory deficits observed in affective patients in the depressed state are transient, secondary manifestations of depression and are neither indicative of underlying organic pathology, nor of abnormal hemispheric laterality. This suggests that memory impairment in depression can be treated by treating depressive symptoms, both chemically and behaviourally. The results also support the view that prophylactic lithium treatment has no adverse effects on these memory tasks.

Memory functioning was assessed in 26 unmedicated patients with major depressive disorder (DSM-III) who were then administered either bilateral electroconvulsive therapy (ECT) (N = 16) or imipramine 200 mg per day (N = 10). The subjects were retested following seven ECT administrations or 21 days of imipramine treatment respectively. The retrograde memory tasks included recall of public and autobiographic events. The anterograde memory tasks included an immediate memory task, a verbal paired-associates recall task, and a non-verbal figure reproduction task. Depression was significantly improved in the ECT-treated subjects but not in those administered imipramine. Both ECT- and imipramine-treated patients showed a deficit in recent anterograde memory relative to their pretreatment performance, but no deficit in immediate memory. ECT-treated patients also had a significant and well-characterized impairment in retrograde remote memory. By contrast, imipramine-treated patients did not show a retrograde memory impairment which could be explained by treatment. The results suggest qualitatively different memory deficits produced by ECT and imipramine.

Although patients suffering from major depression respond to antidepressant treatment within several weeks, full reinstatement of premorbid capabilities requires much longer. Nevertheless, most research in major depression seeking the pathophysiological correlates of remission has focused upon the acute post-treatment period. Brain imaging research offers no exception. We have recently shown that cerebral perfusion in depressed patients responding to 6-wk antidepressant medication increases in parieto/cerebellar regions and becomes similar to that of healthy control subjects. We now present technetium-99m hexamethylpropylene amine oxime single-photon emission computed tomography (99mTc-HMPAO SPECT) data collected from 11 of these patients 2 years in remission. Images were analysed using Statistical Parametric Mapping. After 2 years, perfusion normalization found immediately after treatment was maintained, with further increases in frontal and decreases in parieto/cerebellar regions. These findings suggest that perfusion increases in parieto/cerebellar regions may be involved in acute response to treatment whereas increases in frontal regions may be related to its consolidation.

The purpose of this study was to examine the relationship between age-associated changes in central serotonergic function and abnormalities associated with major depression. Under randomized double-blind conditions, prolactin and cortisol responses to the serotonin-releasing agent d,l-fenfluramine hydrochloride (60 mg orally) and placebo were examined in 30 normal subjects (15 men, 15 women; age range 21–84 years) and 39 patients with major depressive disorder, endogenous subtype (14 men, 25 women; age range 29–72 years). In the normal subjects, a significant Age x Challenge x Time interaction was observed in the prolactin response (p = .03). This was primarily due to the elevated prolactin responses of the younger healthy women. Peak minus baseline (delta) prolactin responses were negatively correlated with age (women, p = .004; men, p = .06). In the depressed patients there was no age-related decline in prolactin response to fenfluramine. When depressed and healthy younger subjects were compared, delta prolactin responses to fenfluramine were significantly blunted in young patients with depression (p = .003) irrespective of the significant effect of gender (p = .01), but not in older depressed patients. Cortisol responses to fenfluramine did not reveal consistent effects of age, gender, or diagnosis. Age-related decline in central serotonergic function may make older individuals more vulnerable to depression and possibly render depressive episodes more frequent, more severe, and less amenable to treatment.