Working hard for oneself or others: Effects of oxytocin on reward motivation in social anxiety disorder

Abstract

There is some evidence to suggest that oxytocin promotes social behavior, especially for disorders characterized by social dysfunction, such as social anxiety disorder (SAD). The goal of this study was to examine the effect of oxytocin on reward motivation in SAD. We tested whether oxytocin promotes prosocial, or antisocial, self-directed decisions, and whether its effects depended on social anxiety severity and attachment. Fifty-two males with SAD received 24 international units of oxytocin or placebo, and completed a reward motivation task that measured willingness to work for self vs. other monetary rewards. Although there was no main drug effect, social anxiety severity moderated the effect of oxytocin. Less socially anxious individuals who received oxytocin worked harder for other vs. own rewards, compared to high socially anxious individuals. Attachment did not moderate this effect. Among people with SAD, oxytocin enhances prosocial behaviors in individuals with relatively lower levels of social anxiety. National Institutes of Health ClinicalTrials.gov Registry #NCT01856530. https://ichgcp.net/clinical-trials-registry/NCT01856530?term=oxytocin+pro-social&rank=2.

Keywords: Motivation; Other; Oxytocin; Reward; Self.

Conflict of interest statement

The authors declare that they have no competing financial interests.

Copyright © 2017 Elsevier B.V. All rights reserved.

Figures

Fig. 1. Schematic diagram of an example “Other” trial from the “Pay-it-forward” Effort Expenditure for Rewards Task (EEfRT)

A) Trials begin with being told whether the upcoming trial is for “Self” or “Other”. B) Subjects are presented with information regarding the reward magnitude of the hard task for each trial, and the probability of receiving any reward for completing that trial, and have 5s to choose to play either the easy or hard task. C) 1s “Ready” screen. D) Subjects make rapid button presses to complete their chosen task for 7s (easy task) or 21s (hard task). E) Subjects receive feedback about whether they have completed the task. F) Subjects receive reward feedback about whether they received any money for that trial.

Fig. 2

Main effect of self vs. other condition across levels of reward probability. Error bars represent standard error of the mean. All condition comparisons of self vs. other p < 0.001.

Fig. 3

Correlations between percentages of hard-task choices for self vs. other by treatment group.

Fig. 4

Significant interaction of drug × social anxiety symptom severity on difference in proportions of high effort choices for self vs. other conditions. Error bars represent 95% CI.