THIS REPORT presents the results of a longitudinal study involving 162 nights of all-night polygraphic recording in six manic-depressive patients who were followed through the various clinical phases of their illness.
Depressed patients have been the subjects of a number of investigations in the sleep laboratory, although usually no distinction has been made between different classes of depression.1-11 No studies of mania have been reported up to now except for a preliminary report from our laboratory.7 Results in depressed patients are conflicting to a certain extent; even the most prominent finding in one study is not noted at all in another. However, some points are clear. A sleep disturbance exists; depressed patients generally have less total sleep than normal subjects, and more awakenings during the night.3-5,8,9 They usually have less stage 4 (deep slowwave) sleep.3-5,8,9,11 The early-morning awakenings traditionally associated