Circadian Timing

This observational behavioural study examines whether individual differences in sleep quality, sleep timing, and chronotype are associated with prosocial allocation decisions in adults. Participants will complete self-report sleep and circadian questionnaires, including the Pittsburgh Sleep Quality Index and the Munich Chronotype Questionnaire, a 7-day sleep diary, and a brief computer-based Dictator Game allocation task. The study does not involve sleep deprivation, sleep restriction, treatment, clinical diagnosis, medication, or medical devices. Participants will not be asked to change their sleep schedule. The Dictator Game decisions are hypothetical and do not affect participants' compensation. The study is intended to describe associations between naturally occurring sleep-related individual differences and behavioural allocation choices, not to diagnose or treat sleep or mental health conditions.