Abstract Introduction Adolescents are exposed to insufficient sleep due to bioregulatory and social pressures. Attention-deficit/hyperactivity disorder (ADHD) may increase vulnerability to the neurobehavioral consequences of this sleep loss. Traditional measures of attention (e.g., median reaction time RT from the Psychomotor Vigilance Task PVT do not capture temporal fluctuations in attention. Time-varying analysis of reaction time can better index moment-to-moment slowing or speeding. We tested whether sleep restriction changes the trajectory of PVT responses over time and whether ADHD traits moderate these effects. Methods Seventy-eight adolescents (range 10.1-15.7 12.2±1.4 years; 42F) completed a 10-minute afternoon PVT after two counterbalanced 5-night at-home sleep conditions: sleep optimization (SO; 10h time-in-bed) and sleep restriction (SR; 7.5h time-in-bed). Youth were indexed for ADHD traits by parent-rated Conners-3 T-scores for inattention (range 40-90 60.1±14.9) and hyperactivity/impulsivity (range 40-90 61.4±17.1). We extracted each PVT response as a reciprocal reaction time (RRT=1/RT). Linear mixed models examined whether RT varied across time-on-task (i.e., elapsed time within the PVT), condition (SO vs. SR), and ADHD status (mean-centered Conners T-scores). Results We identified a series of effects. A significant interaction of time-on-task and condition (b=0.012, p=.017) indicated that after SO, RRT slowed across the task (b=-0.018, p=.12); however, after SR, RRT sped up over time (b=0.021, p=.017). This time-on-task-by-condition effect was moderated by both inattention (b=0.056, p=.001) and hyperactivity/impulsivity (b=0.058, p.001) traits. In both cases, the effect of sleep condition on time-varying RRT was attenuated in youth with lower ADHD traits. Conclusion Sleep restriction altered adolescents’ time-varying attention, with responses increasing over time compared to a temporal slowing after sleep optimization. Youth with higher ADHD traits showed a stronger shift toward this speeded pattern, suggesting a distinct response phenotype under sleep loss. The consequences of these effects are not yet clear; however, they may reflect either a compensatory attention in youth with ADHD, or conversely, a shift towards impulsivity. Future analyses will link these data to other brain-behavioral outcomes to better understand these effects. Support (if any) R01HD103665 (JMS); P20GM139743 (MAC)
Wright et al. (Fri,) studied this question.