Sleep Timing and Duration Predict Levels of Repetitive Negative Thinking the Following Day

Multiple forms of psychopathology characterized by repetitive negative thinking (RNT) are often comorbid with sleep problems. This study aimed to use a longitudinal method to extend previous research regarding this connection. Participants ( N = 127) were undergraduate students who completed daily measures of sleep, mood, and RNT for 18 days that encompassed a transition to and from a holiday break. At baseline, insomnia severity and circadian disruption severity per self-report measure revealed small to moderate correlations with RNT, and these relations remained significant after statistically controlling for the influence of negative affect. When looking longitudinally within person, later bedtimes and shorter sleep durations were predictors of heightened RNT the next day, even after statistically controlling for negative affect. RNT did not predict sleep variables when running the reverse of these models, yet negative affect emerged as a significant predictor of sleep timing and sleep duration. Results indicate that bedtime and sleep duration may be contributors to RNT, and that sleep disruptions may precede the onset of RNT.