Brain activity and the perception of self-agency while viewing a video of tool manipulation: a functional near-infrared spectroscopy study.

Self-agency is the recognition of one's own movement and plays a vital role in purposeful, voluntary movement. Self-agency can occur in individuals who view their own finger movements as they are projected onto a screen and aligned with their actual hand position. Self-agency can also occur when tools are assimilated into the body schema. Here, we examined whether participants perceived self-agency when they viewed a video of a tool that they manipulated and whether the perception of self-agency correlated with simultaneous changes in oxyhemoglobin in the parietal or prefrontal cortical areas. All participants reported the perception of self-agency, which was correlated with oxyhemoglobin increases in the right inferior prefrontal area. We conclude that self-agency also relates to hand-held tools displayed by video.