Voluntary Sleep Choice and Its Effects on Bayesian Decisions.

This study examines whether voluntary sleep restriction at commonly experienced levels impacts decision making in a Bayesian choice task. Participants recruited were largely traditional age college students from a regional state university (n = 100) and a federal military academy (n = 99; n = 56 and 43, respectively, used in final analysis). Sleep was measured by actigraphy over a one-week period, followed by performance of a decision task. The task involved two sources of information, base rate odds and sample evidence, with subjects asked to make a probability judgment. Results found that subjects with nightly sleep < 6 hr (sleep deprived = SD), relative to those with > 7 hr, placed less decision weight on new evidence, relative to base rate information, in making difficult choices. This result is strongest among female subjects. For easier choices, voluntary SD did not affect relative decision weights placed on the two sources of available information.