The effect of sleep quality on daily rumination: implications for the sleep-emotion relationship

The current study examines the effect of objective and subjective sleep indicators on the brooding component of rumination within a daily process design. The indirect effects of brooding on the daily sleep-negative affect relationship were also assessed, along with the moderating effect of dysphoric symptoms on these relationships. Participants were 132 undergraduates (60% female, average age of 20). Participants reported on stress, brooding rumination, and negative affect (NA) every evening for seven days via online survey technology. Participants also kept the Consensus Sleep Diary (CSD; Carney et al., 2012) for the seven days and wore an actigraph monitoring device for objective sleep measurement. Results showed that objective and subjective sleep variables (total sleep time [TST], sleep onset latency [SOL], and subjective sleep quality [SSQ]) predicted next-day brooding rumination. Additionally, SSQ had an indirect effect on next-day NA through brooding despite there being no direct effect of sleep variables. Increased brooding after poor sleep might help to partially explain the link between sleep disturbance and negative emotion.