Study Of The Effect Of Single Dose Testosterone Administration On Decision Making In Healthy Males

In cognitive neuroscience,the role of hormones in decision-making has gradually attracted researchers’ attention.Testosterone is one of the typical steroid hormones.Many studies support the association between testosterone and anti-social behaviors such as impulsiveness behavior as well as aggressive behavior.Decision-making is a common behavior in people’s lives.Previous research mainly focused on brain mechanisms of human decision-making behaviors.Subsequent studies have found that although the single link between hormones and behavior is rare,hormones can affect the brain through genetic or nongenetic pathways,or they can act as neuroactive steroids,which in turn affects decisionmaking.Accordingly,our study aimed to explore the impact of testosterone on decisionmaking using exogenous testosterone administration.Three aspects of decision making were examined: social decision-making,intertemporal decision-making preferences,and the value processing under uncertainty.Study 1 measured the generosity of individuals in social decision-making with a social discounting task.Social distance perception was also measured.The results showed that combined with the hyperbolic curve model of discounting,testosterone significantly increased the discount rate.The generosity decreased as the social distance went further;the analysis of the area under the curve also validated this result.Testosterone administration also made the individual’s perception of social distance become further.Based on Study 1,the replication study of Study1 with larger samples also got the results consistent with Study1.In general,testosterone reduced the generosity of individuals,meanwhile,the decrease of testosterone’s generosity to individuals and the social distant perception were two separate processes.Study 2 used an adaptive time discounting task to investigate how testosterone affect individual impulsiveness in intertemporal decision-making.The of immediate reward in intertemporal decision-making reflected individual impulsivity.Besides,the BIS-11 scale was also used to measure the individual’s impulsivity.Results showed that testosterone did not affect BIS-11 scale score.For the participants received testosterone administration,delay options needed to provide higher benefits in order to reach the equivalent of the subjective value of the delay option to the immediate option,showing a greater impulsiveness to immediate reward.The results of the hyperbolic discounting model fitting also supported this indicator,showing an increase in the individual’s time discount rate with testosterone administration.Study 3 explored individual’s decision preferences and value processing under uncertainty with DEEP task,which combined the cumulative prospect theory to describe the individual’s probability weight function,utility function and loss aversion.We found that subjects were risk-seeking,but testosterone didn’t increase this trend;in decision-making under uncertainty,testosterone reduced the probability distortion of individuals,had no effect on the utility function,and increases individual loss aversion.Meanwhile,model comparison showed that more subjects used the prospect theory model to make decisions,but compared with the number of subjects who used the expected utility theory model to make decisions,the difference did not reach significant level.In summary,our study explored the role of testosterone in decision-making in combination with three pharmacological studies,which can theoretically provide reference and support for testosterone-related psychiatry and serve as a reference for clinical prediction;it can also be used in practice,such as prediction and intervention of adolescents’ abnormal behaviors,prediction of individual impulsiveness and risk attitude,etc.Future research on testosterone and decision-making should be conducted on a large sample of mixed genders,and combined with techniques such as neuroimaging in order to explore in depth and other aspects of decision-making from multiple levels such as neural activity.