The Influence Of Sleep Deprivation On Outcome Evaluation In Risky Decision-making

Sleep is a necessary physiological process of maintaining bodies’ normalphysiological and psychological function. However, with the accelerating pace oflife and unhealthy lifestyles, a growing number of people are suffering the troubleof varying degrees of sleep deprivation (SD). SD can cause a great impact on thepeople’s physical and mental state, which has been studied in the military andother special career fields.Risky decision-making is a high-level cognitive activity, which has been theresearch focus in the fields of psychology, economics and management science.In real life, people often need to make decisions in the state of SD. SD can easilycause a subjective feeling of fatigue, which is characterized by dizziness, lack ofmotivation, irritability, reduced alertness, memory loss, and so on. In the study,we used the ERPs as the main technical means to explore the influence of SD onrisky decision-making’s outcome evaluation with the help of a combination ofmethods of subjective assessment and objective measurement. In our experiment,20normal young volunteers were recruited from auniversity to participate in a risky decision-making task (self-made gamblinggame). Subjective and objective outcome evaluations were both measured beforeand after SD. The experiment was divided into two parts. First, the SubjectiveFatigue Questionnaire and VAS scale were adopted to assess the physical andpsychological changes after SD. At the same time, participants’ subjectiveoutcome evaluations were also assessed by the tool of Subjective OutcomeEvaluation Questionnaire. Second, FRN and P300were used as indexes toexplore the influence of SD on the outcome evaluation.The main conclusions of the study are as follows: After24h SD, participantswere more inclined to take a risk than before. The behavior data showed that after24h SD, the subjective outcome evaluations are not influenced by the SD effects,inconsistent with the electrophysiological brain responses. However, regardlessof the outcome valence (gain or loss) and magnitude (25or5), the FRNamplitude, related to the motivational significance (motivational value) of thefeedback, decreased after SD. The amplitude and latency of P300, thought toreflect the emotional value of the feedback, did not appear to change after SD.We can draw a conclusion that FRN is more sensitive to SD as an index thansubjective outcome evaluation. The earlier processing of outcome motivationalvalue is affected by SD; however, the later processing of outcome emotionalvalue is free from the24h SD effect. The result can partially explain thephenomenon that risky behaviors of participants increase after SD.