The Effects of Trajectory and Endpoint Errors in a Reaching Movement on the Sense of Agency

Abstract

The sense of agency (SoA) refers to the subjective feeling that an individual can control their own action with their own will. However, it is still unclear which aspects of the motor control process precisely affect the sense of agen-cy. In this study, we investigated how the SoA is modulated by the online motor performance (trajectory error) and the outcome of the reaching movement (endpoint error). The results showed that the invalid priming and the visual feedback delay significantly increased both the trajectory and end-point errors and that these errors significantly attenuated the SoA. The further correlation analyses showed that the decrease in SoA was significantly corre-lated with the trajectory error, but not with the endpoint error, when the error was explicitly noticed. We suggest that the deterioration in online motor per-formance, at least in a reaching movement, is the main cause of the attenua-tion in the SoA.