Effects of cognitive arousal and physiological arousal on sleep perception

STUDY OBJECTIVES: Two experiments were conducted to investigate the effect of presleep arousal on sleep perception. Experiment 1 examined the link between presleep cognitive arousal and distorted perception of sleep and compared the relative effect of anxious and neutral cognitive arousal on sleep perception. Experiment 2 compared the relative effect of anxious cognitive arousal and physiological arousal on sleep perception. DESIGN: Participants completed a nap session. Just prior to the nap, the participants were randomly assigned to 1 of 3 groups to receive different arousal manipulations. They were then allowed to go to sleep and were asked to report their sleep perception upon waking. SETTING: Sleep laboratory. PARTICIPANTS: Fifty-four healthy good sleepers in each experiment. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Self-reported sleep, actigraphy-defined sleep, and the discrepancy between them were indexed. In Experiment 1, participants who were experimentally manipulated to experience anxious cognitive arousal during the presleep period reported longer sleep-onset latency. Both the Anxious Cognitive Arousal Group and the Neutral Cognitive Arousal Group exhibited a greater discrepancy between self-reported and actigraphy-defined sleep, relative to participants who received no manipulation. In Experiment 2, participants who were experimentally manipulated to experience anxious cognitive arousal or physiological arousal during the presleep period reported longer sleep-onset latency and shorter total sleep time, and both groups exhibited a greater discrepancy between the self-reported and actigraphy-defined sleep, relative to participants who received no manipulation. CONCLUSIONS: Results suggest that both presleep cognitive arousal and presleep physiological arousal contribute to distorted perception of sleep.