(PS6-B44) Sleep Hygiene Moderates the Relationship Between Total Sleep Time and Negative Affect

College students are exposed to a unique set of stressors related to the transition to college life and a newfound sense of autonomy and independence (Arnett, 2000). Sleep problems are often a challenge for college students due to increased academic demands where they tend to stay up later and wake up earlier the next day in order to meet said demands, thus accumulating sleep debt (Wolfson, 2010). Deficits in sleep duration was one of the most significant predictors of negative affect and internalizing mental health challenges (Peach et al., 2016; Short et al., 2020). Other research has demonstrated that sleep duration is not associated with negative affect but is associated with positive affect (Rossa et al., 2013). These findings highlight how sleep duration is inconsistently associated with negative affect. Sleep hygiene interventions demonstrate promising improvements in sleep duration in college students evidenced by small to medium effect sizes (Friedrich & Schlarb, 2018). Therefore, the present study aimed to examine the role of sleep hygiene in the relationship between sleep duration and affect. Participants were college students (n = 65) between 18 and 37 years old (M = 20.00, SD = 2.89). Participants were mostly female (63.08%, n = 41) and white, non-Hispanic (64.62%, n = 42). The participants completed baseline measures and wore an actiwatch for two nights. For this study, average total sleep time across the two nights was used.  Participants also completed the Sleep Behavior Self-Rating Scale, Modified to measure sleep hygiene at the start of the study (Gallasch & Gradisar, 2007) and the Positive and Negative Affect Schedule (PANAS; Watson et al., 1988) after the second night of sleep. The overall regression model was statistically significant, F(3, 56) = 3.58, p = .019, R² = .16. Participants’ average Total Sleep Time (TST) and sleep hygiene scores were each significant predictors of negative affect, b = 0.20, p = .017 and b = 2.49, p = .008, respectively. There was also a significant interaction between total sleep time and total sleep hygiene scores, t(64) = -2.45, p = .017. Simple slope analysis revealed that TST was positively related to negative affect among people with poor sleep hygiene (p = .039), TST was not related to negative affect among people with moderate sleep hygiene (p = .723), and the relationship between TST and negative affect for people with good sleep hygiene approached significance, indicating a negative relationship (p = .065). We found that total sleep time was a significant predictor of negative affect, consistent with previous research (Peach et al., 2016; Short et al., 2020). In addition, sleep hygiene moderated the association between total sleep time and negative affect, which suggests that total sleep time has a positive or negative impact on negative affect depending on individuals’ sleep hygiene knowledge. Given the moderating role of sleep hygiene, sleep interventions that address sleep hygiene practices may be key to promoting optimal next day cognitive and emotional functioning.