Abstract and Introduction
Purpose of Review: The present review focuses on recent neuropsychological assessments in bipolar disorder, the methodological issues concerning such studies and areas for future investigation.
Recent Findings: A range of neuropsychological deficits has been demonstrated in manic and depressed patients. However, nonspecific factors may confound such studies. Neuropsychological assessments of euthymic bipolar patients suggest that deficits persist during remission. However, there is debate as to how best conceptualise such 'trait' deficits. Similar neuropsychological deficits have been reported in bipolar disorder and in schizophrenia, which has potential nosological implications. The temporal evolution of neuropsychological deficits is unclear. Deficits have been associated with illness progression. However a few recent studies provide evidence of selective neuropsychological deficits in high-risk groups in bipolar disorder. The neural correlates inferred from neuropsychological studies are consistent with reports from functional neuroimaging and neuropathological studies which have identified prefrontal cortex disturbance and disruption of frontostriatal circuits in bipolar disorder.
Summary: Persistent cognitive impairment in bipolar disorder challenges long-held views on the nature of the disorder. Clarification of the cognitive profile is necessary but will require well-constructed, methodologically robust studies. Further investigations in high-risk groups may help to clarify the development and cause of cognitive dysfunction in bipolar disorder.
In 1896 Kraepelin proposed the separation of the psychoses into two distinct groups of dementia praecox and manic depressive insanity. The latter was characterized by an episodic course and benign prognosis, and forms the basis of our modern concept of bipolar disorder. Cognitive dysfunction has been described in patients with bipolar disorder during manic and depressive phases, but recent investigations have demonstrated neuropsychological impairment in euthymic bipolar patients, which poses a challenge to Kraepelin's dichotomy. However, the nature and genesis of neuropsychological deficits in bipolar disorder have yet to be elucidated.
The emphasis of the present review is on recent investigations into cognitive dysfunction in bipolar disorder.
Curr Opin Psychiatry. 2003;16(1) © 2003 Lippincott Williams & Wilkins
Cite this: Cognitive Dysfunction in Bipolar Disorder - Medscape - Jan 01, 2003.
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