0213 Trait-like Vulnerability Of Higher-order Cognition To Sleep Loss And Circadian Misalignment

Abstract

Abstract The degree of cognitive impairment induced by sleep and circadian disruption has been reported to be trait-like for many basic cognitive domains. Individual differences in vulnerability to sleep and circadian disruption remain largely unexplored for higher-order cognitive functions that are critical for real-world tasks. This study simulated repeated continuous operations duty schedules combining sleep restriction and circadian misalignment, and tested executive function, cognitive processing speed, and selective visual attention. 16 adults (7 female) aged 25.8 (±4.5SD) repeated an 18-day protocol, separated by 3 days of ad libitum recovery sleep at home. Participants maintained a habitual self-selected 8h sleep schedule for two weeks then stayed in the laboratory for four days. The laboratory visit included one sleep opportunity per day: 8h on night one, 3h on night two and 3h on mornings three and four. Cognitive testing was performed every 3h during scheduled wakefulness. Executive function and cognitive processing speed were tested with a Stroop Color Word task and selective visual attention was tested with a conjunction visual search task. Stability of individual differences in cognitive function were quantified by intra-class correlation coefficients (ICC) derived from linear mixed effects models with subject as a random factor and visit and battery number as fixed factors. During combined sleep restriction and circadian misalignment, cognitive processing speed (median reaction times for correct responses to congruent, neutral, and incongruent stimuli), executive function (inhibitory control), and visual selective attention (cognitive throughput) were significantly impaired (p