Objective: The objective of this study was to examine verbal fluency in a group of patients with bipolar disorder (BPD) during an acute episode of mania, and to determine whether performance was related to disease chronicity. We hypothesized that manic patients with BPD would be impaired on verbal fluency, and that this impairment would be greatest in those individuals who had experienced a greater number of manic episodes.
Method: Forty-five manic inpatients with bipolar disorder, and 30 healthy volunteers completed tests of phonemic and semantic verbal fluency. The patients were dichotomized into those experiencing their first episode of mania (FE) and those who had experienced multiple episodes (ME).
Results: On the phonemic fluency task, ME patients produced significantly fewer words than both healthy volunteers and FE patients, and they made a greater number of errors. No significant group differences in overall output were found on the semantic fluency task, although the ME group was more error-prone than were the other groups.
Conclusions: These findings suggest that verbal fluency is more impaired in ME patients than in patients who have experienced only a single manic episode.