Express: The Impact of Humanoid Robot’s Presence on Human’s Cognitive Control in a Stopsignal Task

Motor inhibition - a key aspect of cognitive control - is crucial in interactive contexts, where partners must suppress and adjust actions for optimal coordination. Previous findings has showed that the presence of a human partner impair motor inhibition in joint action tasks. This study investigated whether a similar effect would occur when replacing the human partner with a humanoid robot. To do so, we conducted four experiments using a Stop-Signal Task: (1) a non-engaging robot condition, (2) an engaging robot condition, (3) an engaging robot with disabled cameras, and (4) a human partner condition. Results showed that humanoid robots do not impair motor inhibition, unlike human partners. Instead of increasing cognitive demands, the presence of a humanoid robot appeared to enhance attentional focus when perceived as monitoring, leading to improved motor inhibition. These findings suggest that humanoid robots can be integrated into joint action tasks without compromising cognitive control. Thus, we conclude that, if implemented ethically, robots could offer advantages in collaborative tasks where humans cannot, highlighting their potential for enhancing human performance in shared activities.