Speech Understanding in Manic and Depressive Episodes of Mood Disorders

The aim of this study was to assess the perception of speech in adverse acoustic conditions during manic and depressive episodes of mood disorders.

Forty-three patients with bipolar disorder (mania, N=20; depression, N=23) and 32 patients with unipolar depression were included for analyses. Thirty-five participants served as the control group. The study of speech understanding was carried out using the Polish Sentence Matrix Test, allowing for the determination of the speech reception threshold (SRT). The test was performed in the clinical groups both during an acute episode and remission; during remission, patients underwent audiometric evaluation.

Compared with control subjects, patients with mood disorders had worse speech understanding (higher SRT), regardless of the episode or remission. A manic episode in the course of bipolar disorder was not associated with worse speech understanding compared with remission of mania. However, an episode of depression in the course of both bipolar disorder and unipolar depression was associated with worse speech understanding compared with remission of depression. In bipolar depression, this correlated with age, duration of the disorder, number of episodes, and number of hospitalizations, as well as in remission with age and duration of illness. In unipolar depression, poor speech understanding was more severe in individuals with hearing impairment.

These findings revealed that patients with mood disorders had impaired speech understanding, even while in remission, and manic episodes in the course of bipolar disorder were not associated with impaired speech understanding compared with mania remission.