LAUSR

Chronic insufficient sleep is prevalent in early adolescence with potential neurobehavioral consequences. However, individual differences examining such outcomes are understudied. Using psychomotor vigilance task (PVT) performance, we examine ADHD traits as a potential factor contributing to the vulnerability of performance following insufficient sleep in youth. A preliminary sample of 22 children (11F; 12.25±0.91yrs) were characterized as either high [n=10] or low [n=12] on Conners-3-Parent ADHD-Probability Index [>=/< 50%tile]. In our crossover at-home protocol, 5 stabilization nights (10h time-in-bed[TIB] set to habitual risetime) were followed by 5 nights of sleep optimization (SO; 10h TIB) or restriction (SR, 7.5h TIB; delaying bedtime and advancing risetime equally), then restabilization for 2-4 nights, and the reverse SO or SR condition. Sleep was monitored via wrist-worn actigraphy (Micro MotionLogger). Following SO or SR, participants completed a 10-minute PVT as part of a larger battery administered in the lab in late afternoon. Primary variables included: mean reciprocal reaction time (RRT), mean of the 10% fastest (FRRT), and 10% slowest (SRRT) RRTs. Mixed-effects ANOVA evaluating condition (SO vs. SR) and group (low- vs. high-ADHD) showed a significant main effect of condition (F(1, 20)=10.91, p=.004, ηp2=.35) with slowed RRTs after sleep restriction (m±sd(1/s): SO=3.31±¬0.46; SR=3.07±0.58), no main effect of group or group-by-condition interaction (ps>.42). No significant effects emerged for FRRT (ps>.13); however, a significant group-by-condition interaction on SRRT(F(1, 20)=4.78, p=.04, ηp2=.19) indicated that only the low-ADHD group demonstrated slower SRRT with SR (SO=1.84±0.45, SR=1.61±0.54), an effect not evident in the high-ADHD group (SO=1.64±0.50, SR=1.69±0.61). These preliminary data indicate that sleep restriction on a simulated school-night schedule impairs vigilance in young adolescents as in adults. While overall SR reaction times were slower for all participants, SR impacted the slowest 10% of RTs specifically in the low-ADHD group. In ongoing analyses, we are evaluating two empirically testable explanations for this effect: (1) potential floor or ceiling effects in the high-ADHD group (2) a paradoxical hyperactivity following sleep loss in the high-ADHD group. R01HD103655; P20GM139743