The Effects Of Acute Social Stress On Motivational Reversal Learning And The Interventional Effects Of Oxytocin

Cognitive flexibility allows people to quickly adjust behavioral responses to the changing environment,but there are large individual differences—individuals with lower cognitive flexibility are more vulnerable to be maladaptive in changing environment.This project investigated whether acute social stress affected individuals’ ability to flexibly learn new rules during consecutive reversal of rules for approaching or avoiding threat stimuli,and whether oxytocin could play an intervening role.Two laboratory studies were conducted.In study 1,we recruited 50 male and 50 female college students.Participants firstly underwent the Trier Social Stress Test to induce acute social stress or a non-stressful control task,and their learning performance were tested with the Motivational Reversal Learning Task of which task rules switched between approaching threat scenes and avoiding threat scenes.In study 2,we recruited101 male college students.Participants firstly received intranasally 32 IU oxytocin or placebo in a double-blind design,and then underwent the same procedure as in Study1,to test the effects of oxytocin on motivational reversal learning under stress.In Study 1,we found that when task rule was avoiding threat scenes,male-stress group scored significantly lower than male-control group on all behavioral indicators,including correct rate,reversal sensitivity,win-stay rate,and lose-shift rate.Sex and stress had interaction.Specifically,for males,male-control group scored higher on all indicators under the avoidance rule(vs.the approach rule),whereas the performance of male-stress group did not differ by task rules.While for females,the female-stress group scored higher on correct rate,win-stay rate,and lose-shift rate under the avoidance rule(vs.the approach rule),but the performance of female-stress group did not differ by task rules.In addition,systolic blood pressure of the male stress group was negatively correlated with correct rate and reversal sensitivity under the approach rule,and with win-stay rate under the avoidance rule.In study 2,we found that oxytocin administration did not significantly moderate the effect of stress induction on blood pressure,heart rate,salivary cortisol,or subjective mood states.Yet,there is a trend effect that oxytocin might increase the loseshift rate in stress group under the avoidance rule and cause the stress group to exhibit higher lose-shift rate under the avoidance rule than under the approach rule.The results indicate that acute social stress can impair cognitive flexibility in healthy young men when task situations switch from approaching to avoiding threat scenes.The underlying mechanism is related to sympathetic nervous system arousal,and there exists some sex difference in such behavioral and biological mechanism.Oxytocin can relieve the impairment of cognitive flexibility by acute stress.In terms of behavioral patterns,oxytocin can improve the performance of stress group to be more like that of the placebo-control group.These findings suggest the potential of oxytocin in the prevention and treatment on stress-induced negative cognitive consequences and provide evidence for clinical use of oxytocin.