Studies on healthy adults reveal either unclear or inconsistent results regarding the proximal, day-to-day relationship between sleep characteristics (sleep duration, continuity, timing) and different dimensions of mood (positive affect, PA, and negative affect, NA). In addition, while experimental evidence suggests that sleep changes can impact mood by exaggerating people’s emotional response to environmental factors, few studies have tested whether these findings generalize outside the laboratory. The current study aimed to examine 1) a bidirectional model of sleep and mood, and 2) the effects of sleep characteristics on affect reactivity, a measure of emotional response to daily experiences. Participants were healthy, midlife adults (30-54 yrs old, N =462) drawn from the Adult Health and Behavior Project- Phase 2 study. Across a 4-day monitoring period, sleep characteristics were measured via actigraphy and ecological momentary assessment methods were used to collect repeated measures of participants’ affect, work and social experiences. Affect reactivity was quantified as momentary changes in affect following these experiences. Using hierarchical linear modeling, we tested whether participants’ sleep characteristics on a given night predicted next-day affect and vice versa, and we tested whether sleep characteristics influenced affect reactivity. We found higher levels of PA predicted later sleep timing (B =.23, p =.012), but there were no other significant associations between sleep characteristics, PA and NA (p’s >.05). Sleep characteristics did not moderate the effects of daily experiences on either PA or NA (p’s >.05). There were significant individual differences in several of the relationships between sleep, affect, and affect reactivity (p’s <.05). Overall, our findings suggest that day-to-day fluctuations in behavioral sleep patterns generally do not associate with subsequent affective experience. There may be graded and cumulative effects of sleep disruptions on affect and affect reactivity that are not observed in the context of small, daily fluctuations in sleep characteristics
