P069 Sleep Restriction Impairs Integration of Multiple Information Sources in Probabilistic Decision-Making

Abstract Introduction Sleep loss affects overall decision-making, but its effects on specific mechanisms of decision-making are less well-understood. Here, we examined the effects of sleep restriction (SR) on the ability to integrate multiple information sources on a probabilistic decision-making task. Methods We recruited 41 healthy participants (n=41; age=27.9±6.0years, 20F), 27 of whom underwent well-rested ( WR 4 nights of 9-hours time-in-bed) and SR (3 nights of 3-hours time-in-bed) conditions in counterbalanced order. On the last day of each lab stay, participants completed a probabilistic decision-making task twice – 2-hours after wake (AM) and 12-hours since habitual wake (PM). On each trial, participants were shown two boxes with different proportions of black/white balls. Eight balls were drawn randomly, with replacement, from an unknown box. Participants determined the selected box using easier-to-understand numerical odds and harder-to-understand draw outcome information. Mathematical modelling was used to infer weights placed on each source of information. Results For AM and PM sessions, participants placed significantly greater weights on odds relative to draw information during WR (p<.001 for both). For AM trials, SR significantly reduced weights given to draw information (p=.041), and reduced weights given to odds at marginally significant levels (p=.062). For PM trials, SR reduced weights given to draw information at marginally significant levels (p=.059). Conclusion While well-rested individuals generally rely more on easier-to-understand information, SR impairs decision-making by further reducing individuals’ ability to consider more complex information. This has implications for high-risk professions where SR is common (e.g. doctors) and impaired decision-making may pose serious consequences.