0167 Examining Whether Increased Practice Moderates Total Sleep Deprivation Impairments in Dynamic Decision-Making

Abstract Introduction Research has shown that total sleep deprivation (TSD) disrupts performance on fast-paced, dynamic decision-making tasks where the correct response is learned from trial-and-error and where conditions can change without warning. These impairments are believed to be driven by underlying problems with learning and updating the correct responses from feedback. However, previous studies have only investigated the effect of TSD on dynamic decision-making before and after a night of wake. It is unclear whether increased practice would moderate TSD-driven decrements. To elucidate this, we increased the number of task administrations throughout TSD. Methods N=13 healthy, normal sleepers (ages 26.7+7.3, 9 females) participated in a 4-day, 3-night in-laboratory study. Following 9h baseline sleep (22:30–07:30), participants underwent 39h TSD, with subsequent 9h recovery sleep (22:30–07:30). Every 12 hours, participants completed 1 of 4 versions of a dynamic decision-making task, the Go/No-Go with reversal (GNGr). The GNGr was administered at 2, 14, 26, and 38-hours of wakefulness. Participants had to learn from feedback which two-digit stimuli required a keypress (go) or no response (no-go) and when to update their responses as the contingencies unexpectedly reversed. A signal detection framework was used to calculate discriminability, or the ability to differentiate between go and no-go stimuli. Performance was split into pre- and post-reversal phases, and each phase was divided into 3 equal blocks. We analyzed discriminability using mixed-effects ANOVA, with fixed-effects of session (1-4), phase (pre/post-reversal), block (1-3), and their interactions, with a random intercept over participants. Results Performance during the TSD sessions (3 and 4) was significantly worse compared to the rested sessions (1 and 2; ps≤0.026). Contrary to expectations, performance did not significantly improve from session 1 to 2 (p=0.246). Conclusion Increasing administrations did not abolish TSD-related decrements. Unlike previous studies, participants did not improve across rested sessions. The interval between rested sessions in our study did not include a period of sleep, possibly indicating that sleep is needed to meaningfully improve performance across earlier sessions. Future studies should investigate whether TSD impairments in dynamic decision-making are dose-dependent and at what specific dose significantly impairs decision-making. Support (if any) ARO award W911NF2210223, subaward SUBK00016350