0180 Behavioral Changes in Executive Control over the Course of Sleep Deprivation

Abstract Introduction Sleep deprivation (SD) impairs cognitive performance, but its specific effects on executive function remain less well understood. In this study, we analyzed Go/No-Go (GNG) task data to examine how sustained attention (Go Accuracy; GA) and inhibitory control (No-Go Accuracy; NGA) change over the course of SD, and whether these changes can be explained by declines in vigilance, as measured by Psychomotor Vigilance Test (PVT) performance. Methods Forty-five healthy adults (ages 20-43) underwent a 28-hour period of SD. During SD, participants completed a GNG task four times and performed 17 hourly PVTs. PVT1 (baseline) was administered at 19:00 (Day 1) and PVT16 at 10:00 (Day 2). PVT16 was chosen over PVT17 for being closer to GNG4 time. Data were analyzed using repeated-measures ANOVA, with PVT change (PVT16 minus baseline) included as a covariate to control for vigilance decline. Results For GA, the main effect of Time (p = .027) indicated that GA significantly declined across the SD period. A significant Time×PVT change interaction (p .001) and a significant Between-Subjects PVT effect (p = .021) showed that declines in PVT performance predicted lower overall GA and that this relationship varied across time. For NGA, the main effects of Time (p = .029), Time×PVT change interaction (p = .040) and Between-Subjects PVT (p = .016), were also significant. These findings indicate that participants with greater PVT decline showed lower overall NGA and that the strength of this relationship depended on the time of day during SD. Conclusion Sustained attention and inhibitory control both declined over the course of sleep deprivation, and these impairments were strongly linked to individual differences in vigilance loss, with participants showing greater PVT decline exhibiting larger reductions in Go and No-Go accuracy. However, deficits persisted even after controlling for vigilance, indicating that sleep deprivation impairs executive processes directly and not solely through reduced alertness. Support (if any)