Aim of the study:
The aim of the study was to compare neuropsychological functioning across different states of bipolar disorder: mania/hypomania and depression.

Subject or material and methods:
Cognitive functions were examined in 30 depressed bipolar patients aged 18-68 who fulfilled DSM-IV criteria for depressive episode (Hamilton Depression Rating Scale score ≥ 11) and 30 manic or hypomanic bipolar patients aged 23-68 who fulfilled DSM-IV criteria for manic or hypomanic episode (Young Mania Rating Scale ≥ 11). The comparison group consisted of 30 healthy subjects aged 23-71 without history of psychiatric or neurological disorders. A neuropsychological battery assessed executive functions and fluency (Wisconsin Card Sorting Test – WCST and Controlled Oral Word Association Test FAS, Stroop Color-Word Interference Test), working memory and attention (Trail Making Test Part B - TMT, N-back Test), psychomotor speed (TMT A) and reaction time (N-back Test).

Results:
The bipolar groups showed cognitive dysfunctions in working memory, fluency, attention, psychomotor speed and reaction time in relation to the comparison group. The manic/hypomanic group was also impaired on WCST, a measure of executive functions, which was not observed in depressive patients. Manic/hypomanic patients were significantly more impaired on executive functions than the depressed group.

Discussion:
The obtained results are partly consistent with the previous results.

Conclusions:
A poorer neuropsychological performance was observed in different states of bipolar disorder but during manic/hypomanic state cognitive deficits were more serious regarding executive functions.