Neuropsychological performance in partly remitted unipolar depressive patients: focus on executive functioning.

BACKGROUND

Only few studies have investigated executive impairment in the euthymic phase of unipolar affective disorders, yielding diverging results. The role of impulsivity/orbitofrontal associated executive functioning in remitted depression has not yet been examined.

METHODS

Partly remitted male out-patients (n = 15) with non-psychotic major depression (MDD) were compared with healthy males (n = 15) on several neuropsychological tests. Executive tasks focussed on orbitofrontal function (Go/No-Go, Iowa Gambling Task (IGT), delayed alternation task). Furthermore, the Barratt Impulsiveness Scale (BIS-11) was administered to all subjects.

RESULTS

Executive skills of the patients were largely unimpaired. Patients exhibited significant deficits on measures of verbal memory only. Residual depressive symptoms in patients were correlated with diminished response inhibition. BIS-11 scores were not elevated in the patients.

CONCLUSIONS

Both executive impairment related to orbitofrontal function and self-reported impulsive behaviour in major depression seem to be state-dependent. In accordance with other studies, patients with remitted unipolar depression showed a persistent verbal memory loss.