Presleep cognitive hyperarousal and affect as factors in objective and subjective insomnia.

The role of presleep cognition in insomnia was studied in normal sleepers and insomniacs with either (1) psychophysiological insomnia, an objective disorder of initiating and maintaining sleep (DIMS), or (2) DIMS without objective findings (subjective insomnia), as defined by two nights' polysomnographic baseline data. During the experimental night in the sleep laboratory, 24 subjects were interviewed at intervals during the presleep/sleep-onset period. Judges' ratings of subjects' spontaneous reports and subjects' responses to questionnaire items were analyzed for cognitive quality. Objective insomniacs had more frequent cognitive activity than the subjective insomniacs. Both insomnia groups reported more negative thoughts than the controls. Cognitive hyperarousal as a factor in objective insomnia was not clearly supported.