Moderating Effects Of Oxytocin On Perceptions Of Inequity And Its Neural Representation Patterns

In the development of human societies,people have always sought fair outcomes and have strong objections and negative feelings towards inequity,so it is important to explore people’s perceptions of fairness,inequity and how they are regulated.There is a large body of research that demonstrates the importance of oxytocin in modulating social behaviors such as trust,cooperation and information processing,but only a small number of behavioral studies have investigated the modulation of oxytocin in human fairness decision-making,and the experimental tasks used in these studies have mainly examined subjects’ perceptions of inequity in gain situations,but people also face unfairness in loss situations.It is not clear whether oxytocin regulates perceptions of inequity differently in gain and loss contexts.Based on the above studies,our study explores the moderating effects of oxytocin on advantageous inequity and disadvantageous inequity in the context of gaining and losing benefits by revising the classical paradigm of the payoff distribution task,we also explore more refined behavioral patterns and neural mechanisms in combination with computational modeling and f MRI.The design used in this study was a randomized double-blind placebo-controlled between-subject design.A total of 80 healthy male university students were recruited to participate in our study,after 45 minutes of intranasal spraying of oxytocin or placebo,subjects were asked to complete a decision-making task about the outcome of an unequal distribution in the context of gaining and losing benefits.On the behavioral level,oxytocin increased subjects’ fairness rating,preference rating and choice rates for unequal options in the advantageous condition,but did not moderate the gain or loss of benefits.Fitting statistical analyses of behavioral outcomes using an inequity aversion model revealed that oxytocin reduced aversion to advantageous inequity,in addition to increasing aversion to disadvantageous inequity.At the neural level,parametric modulator analyses based on fairness ratings found stronger activity in the dorsolateral prefrontal cortex and dorsal anterior cingulate cortex in response to allocations of advantageous inequity compared to disadvantageous inequity in the OT than the PLC group.These results suggest that oxytocin has similar moderating effects on perceptions of unfairness in both gain and loss contexts,and that oxytocin reduces perceptions of unfairness by increasing individuals’ preferences for advantageous inequity,and that these moderating effects of oxytocin are closely related to the dorsolateral prefrontal cortex and the anterior dorsal cingulate gyrus,which are involved in cognitive control and conflict detection.In contrast to disadvantageous inequity,individuals need to weigh benefits against rules in advantageous inequity,and oxytocin may increase individuals’ attention to benefits and enhance their cognitive control processing in order to make them more likely to accept outcomes that are more self-beneficial,thereby influencing perceptions of fairness.