Neural correlates of increased risk-taking propensity in sleep-deprived people along with a changing risk level.

Risky decision-making under a changing risk level is a complex process involving contextual information. The neural mechanism underlying how sleep deprivation (SD) influences risky decision-making behaviors with a changing risk level has yet to be elucidated. In this study, we used the Balloon Analogue Risk Task (BART) during functional magnetic resonance imaging to investigate the neural correlates of SD-induced changes on decision-making behaviors at different risk levels. Thirty-seven healthy male adults were recruited in this within-subjects, repeat-measure, counterbalanced study. These individuals were examined during a state of rested wakefulness state and after nearly 36 h of total SD. The results showed that SD increased the activation of risk modulation in the left inferior frontal gyrus and were positively correlated with risk-taking propensity after SD. Activation in the ventral striatum and thalamus during cash out was increased, and activation in the middle temporal gyrus after explosion (loss of money) was decreased in sleep-deprived subjects, providing additional evidence for greater risk-taking propensity after SD. These results extend our understanding of the neural mechanism underlying alteration of the risk-taking propensity in sleep-deprived individuals.