The effect of social-comparative feedback on corticospinal excitability and balance performance


Providing positive social-comparative feedback (e.g., "you performed better than the group") results in an enhanced level of motivation and self-efficacy, as well as an improvement in balance performance compared to negative (e.g., "you performed worse than the group") or no feedback (Lewthwaite & Wulf, 2010). However, the neural processes contributing to the motor and cognitive benefits of social-comparative feedback have yet to be determined. Thus, the purpose of this study was to examine whether social-comparative feedback alters corticospinal excitability and consequently, balance performance. Thirty-six young adults (18 males) completed a balance task (i.e., standing on a stabilometer) eight times. After three of these trials, the control group received their performance outcome (i.e., time on balance) while the other two groups received positive or negative social-comparative feedback. Before and after each instance of feedback, corticospinal excitability was assessed using transcranial magnetic stimulation. Results indicated that by the end of the eight trials, participants in the negative group rated their balance ability to be 47 and 51% lower than those in the control and positive groups respectively (p<0.001). Despite this difference in perceived skill, all groups improved their balance performance by ~47-54% across all trials (p<0.001). However, this change in performance was not matched by any changes in corticospinal excitability (p=0.340). These findings suggest that the benefits of social-comparative feedback are unlikely to be mediated by neural processes at the corticospinal level. However, future studies are needed to confirm this finding due to the social-comparative feedback having minimal effect in this study.