0099 The Effects Of Prior At-home Sleep Duration On Reversal-learning During A "Shoot/No-Shoot" Task. (12th April 2019) - LaFollette, Kyle
Abstract: Introduction: The ability to quickly adapt to changes in the environment requires flexible thinking and updating of task-relevant information. However, both sleep loss and stress have been found to produce significant degradation in this type of cognitive performance. In this study, we investigated whether differences in total sleep time (TST) and wakefulness after sleep onset (WASO) were predictive of performance on a reversal-learning task. We hypothesized that TST and WASO would predict weaker discriminability and greater response bias following a change in stimulus-response rules. Methods: 63 adults (41 F; 21.7 ± 2.8 yrs) completed ~7 days (6.64 ± 0.96) of at-home actigraphy, followed by an in-laboratory session, which included a prolonged psychosocial stressor. Subjects performed a "Shoot/No Shoot" (SNS) task - a modified go/no-go paradigm. The SNS task required subjects to distinguish between enemies and allies using two pre-defined rules based on uniform color (tan vs. green) and environment (urban vs. rural). Subjects were required to shoot (go) or not shoot (no-go) based on the stable two-factor rule. Following instruction, the contingencies were reversed midway through the task, such that enemies became allies and allies became enemies, requiring subjects to learn the new stimulus-response rules. We quantified performance by decision criterion (response bias; c ) and discriminability ( d' ). At-home TST and WASO were assessed for the night prior to the in-lab session. Results: In the interest of reversal learning, all analyses were restricted to the first 40 trials post-reversal. Simple linear regressions showed that TST significantly predicted c; F(1, 61)=7.94, p=0.006, R 2 =0.115. Subjects with shorter TSTs prior to the in-lab session displayed stronger response bias (larger c ). There was no association between TST and d' . WASO was not found to be significantly related to c or d'. Conclusion: These findings indicate that shorter sleep duration is associated with increasing tendency to "shoot" following a change in situational demands. Such findings emphasize the importance of regularly obtaining recommended sleep durations and managing fatigue, especially in safety critical operations that require flexible thinking. Support (If Any): CDMRP grant W81XWH-17-C-0088