Limited change in adolescent value-based risk choices following acute sleep restriction and caffeine.

PURPOSE: Adolescence is marked by changes in brain connectivity linked to risk decision-making, indexed by risk-taking propensity, optimal choices (safe, higher expected value), and irrational choices (risky, lower expected value). Insufficient sleep and caffeine consumption, common during adolescence, may independently and jointly influence risk decision-making in adolescents already predisposed to risk-taking. This study investigated whether sleep-restriction impairs risk decision-making, whether caffeine increases risk-taking propensity and optimal choices while decreasing irrational choices, and whether caffeine effects are enhanced under sleep-restriction. METHODS: Forty-one adolescents aged 14-17 years completed a between-subject, two-night sleep manipulation (sleep-restriction: 6 h time in bed, sleep-extension: 9.5 h time in bed), followed by a within-subject, double-blind, placebo-controlled caffeine manipulation. Risk decision-making was assessed using a modified Wheel of Fortune task, and Bayesian inference quantified sleep and caffeine effects. RESULTS: Across all outcomes, posterior estimates for sleep condition, caffeine, and their interaction were small, with 95% highest density intervals spanning zero; region of practical equivalence overlap varied across predictors, indicating limited evidence for practically meaningful effects. Caffeine effects and sleep-caffeine interactions remained uncertain across outcomes. DISCUSSION: Adolescent risk decision-making on the modified Wheel of Fortune task showed no clear evidence of practically meaningful average changes after two nights of sleep-restriction or acute caffeine. These results suggest limited sensitivity of this task to the present manipulations rather than evidence that sleep or caffeine is inconsequential. Findings provide quantitative effect size and uncertainty benchmarks for future experimental work. CLINICAL TRIAL REGISTRATION: https://www.humanforschung-schweiz.ch/en/trial-search/study-detail/58864/translate/en/, identifier SNCTP000004988.