0178 Cumulative Effects of Mild Sleep Restriction on Lapses of Attention

Abstract Introduction Sleep deprivation leads to detriments in performance, including alertness and vigilance. Less is known, however, about the cognitive impact of mild sleep restriction, including whether negative outcomes are time-dependent and cumulative. We tested the impact of sleep restriction on sustained attention in a multi-week, crossover experiment in a controlled laboratory setting. Methods Sixty-six young adults (Mage = 20.03; 53.0% female; 51.5% non-white) completed seven nights of in-laboratory testing, spread across 3-weeks. On the first week, participants completed a polysomnography adaptation night and baseline assessments including the psychomotor vigilance task (PVT) in the evening (9:00PM) and in the morning (7:30AM) with buffer time to prevent sleep inertia following initial awakening. During the following week, participants completed either three nights of sleep restriction (5 hours of sleep/night) or three nights of normal sleep (8 hours of sleep/night), with PVT testing each morning and evening. After a four-night washout period, participants returned to complete the other sleep condition (order counterbalanced). Research assistants who administered the PVT were kept blinded to the participant’s sleep condition. Results Relative to normal sleep, three nights of sleep restriction significantly worsened PVT mean reaction times (RTs; M = 361 ms versus M = 390 ms; t(65) = 4.38, p .001, d = .54) and number of lapses (M= 3.78 versus M = 5.80; t(65) = 5.00, p .001, d = .62]. There were no main effects of time of day or interactions with sleep condition (ps.05). However, study day significantly interacted with sleep condition (F(2, 128) = 3.42, p = .036, η2 = .051) such that the negative impact of sleep restriction on lapses worsened across the week (night 1: Mdiff = 1.59, night 2: Mdiff = 0.88; night 3: Mdiff = 3.26). Conclusion Mild sleep restriction quickly produces detriments in sustained attention, with effects being cumulative across repeated days of sleep loss. Support (if any) This study was supported by the National Science Foundation (1920730).