Influence of competition on motor inhibitory control: Evidence from a go/no-go task

The present experiment examined how individuals' motor response execution and inhibition - as measured by a Go/No-Go (GNG) task - is modulated by social influence arising from competition. We found that participants in a competition group responded significantly faster to frequently occurring Go stimuli than those in a control group, while no between-group difference in accuracy was found. This indicates that competition leads participants to favor a response strategy of maximizing the speed of prepotent motor response execution without sacrificing accuracy. In addition, participants in the competition group committed significantly more errors to infrequently occurring No-Go stimuli than those in the control group. Together, these findings suggest that competition speeds up prepotent motor response execution, which comes at the cost of reduced prepotent response inhibition. Furthermore, increased errors in prepotent response inhibition due to competition correlated positively with self-reported trait competitiveness and trait motor impulsivity, identifying the link between personality traits and competition-induced attenuation of inhibition efficiency. Our signal detection analysis revealed that these behavioral effects can be attributed to a combination of a pronounced tendency to respond in general to both Go stimuli and No-Go stimuli, as evidenced by increased response bias (C), and reduced discrimination of No-Go stimuli from Go stimuli, as indexed by decreased sensitivity (d'). Our experiment offers novel insights into how motor control is modulated by engaging in competition.