An EEG sleep study of a bipolar (manic-depressive) patient with a nocturnal switch process.

Fifty-eight all-night polygraphic sleep recordings were obtained on an unmedicated female bioplar (manic-depressive) patient who switched into and out of mania eight times. While depressed she was hypersomniac and exhibited elevated Rapid Eye Movement (REM) sleep time and short REM latency. On four nights, she apparently switched into mania while asleep. The last recorded sleep stage in each case was REM sleep.