Psychological treatments for cognitive dysfunction in major depressive disorder: current evidence and perspectives.

BACKGROUND: Patients with mood disorder, both unipolar and bipolar, present with significant cognitive dysfunction while unwell and this persists into euthymia. This impairment is to an extent independent of mood symptoms, has significant implications for prognosis, and exerts an effect on overall functioning. Neurobiological data suggest that the cognitive dysfunction may relate to underlying dysfunction of pre-frontal cortical areas of the brain and their connections with limbic structures.
METHODS: In this paper we examine the theoretical and neurobiological rationale for psychological treatments which focus on the treatment of cognitive dysfunction. We systematically review preliminary studies using cognitive rehabilitation (CR) based techniques in mood disorders, focussing on clinical contexts in which CR may be particularly likely to be important. In addition we examine important methodological issues in developing such an approach.
RESULTS: There is little evidence of traditional psychotherapies having a beneficial effect on cognitive function. However, there are a small number of studies examining specific CR in major depression and in bipolar disorder. The studies are small and inconclusive. However data on neuropsychological function and neurobiology of major depression suggest that this is an approach which deserves further attention and research.
CONCLUSION: Further research is required in carefully selected populations, using well defined CR techniques and appropriate comparator treatments. Combination of these techniques with pharmacological and broader psychological treatments is likely to be most effective.