0226 Effect of Wake Extension and Short Recovery Sleep on Objective Vigilance and Subjective Sleepiness in Young Adolescents

Abstract

Abstract Introduction Adolescents routinely experience insufficient sleep. Compared to adults, less is known regarding how wake extension and recovery sleep impact objective and subjective indexes of vigilance in youth. Here we explore these questions using acute wake extension. Methods Twenty-two 10–13-year-old children (12.03±1.14 years, 12F) completed a week of actigraphy-monitored at-home sleep stabilization (9.5h TIB). Participants then slept in the laboratory with polysomnography for a baseline (BSL) opportunity of 9.5h (21:00-06:30) and returned the subsequent evening for wake extension (WE) to 02:30 and a 4h recovery sleep opportunity (02:30-06:30). Participants completed performance testing batteries including a 5-minute tablet-based visual adaptation of the psychomotor vigilance task (PVT; BrainBaseline) and introspective ratings at 20:00 and 07:30, as well as at three additional times during WE: 22:00, 00:00, and 01:30. The current analyses focused on PVT reciprocal reaction time (RRT: 1/RT) and the Stanford Sleepiness Scale (SSS) ratings. Results One-way ANOVA across WE (20:00, 22:00, 00:00, 01:30) showed a main effect of time for slower reaction times as participants remained awake (m±sd [1/s] 20:00: 2.01±0.32; 22:00: 1.84±0.33; 00:00: 1.79±0.29; 01:30: 1.71±0.34; F(3,63)=13.78, p<.05, ηp2= .40). After recovery sleep, RRTs at 07:30 (1.69±0.31) were slower than those at 07:30 after baseline sleep (1.95±0.36) (t(21)=5.46, p<.001) and did not differ from 01:30 during WE (t(21)=0.64, p=0.53), indicating persistent impairment after recovery sleep. A main effect of time during WE was also seen for the SSS (20:00: 1.77±0.69; 22:00: 3.36±1.71; 00:00: 4.14±1.21; 01:30: 5.68±1.25; F(3,63)=56.80, p<.001, ηp2= .73). Morning SSS scores were higher (sleepier) on WE (2.24±1.30) than BSL (1.71±0.90) (t(20)=2.45, p=.024). However, unlike RRTs, morning SSS scores were also significantly lower (less sleepy) at 07:30 following recovery sleep compared to 01:30 during WE (t(21)=9.80, p<.001). Conclusion Vigilance performance and sleepiness after 13.5 until 19 h awake worsened and PVT performance did not improve after 4h recovery sleep; however, perceived sleepiness after 4h recovery sleep decreased. This incongruent performance and perception confirms the vulnerability of youth to even partial sleep loss. Our next analyses will consider inattention phenotypes and recovery sleep physiology as potential moderators of these effects. Support (if any) K01MH109854, P20GM139743