Somatosensory feedback from fingers accelerates body representation update

The purpose of our study is to clarify dominant factors and process to induce an embodiment about a robotic limb. The embodiment contributes to fast and precise motion control of the robotic limb since a motion command could be designed in advance for a feedforward control using the body representation including kinematics and dynamics of the robotic limb. The embodiment about the robotic limb will be therefore proportional to task performance of the robotic limb controlled by an operator. This paper compares task performance of an Extra Robotic Thumb (ERT) when different kinds of sensory feedback are separately given. In a reaching task of the ERT, three kinds of sensory feedback from the reaching point are given, tactile and position feedback from a finger, ones from a face, and auditory feedback. We confirmed that the somatosensory feedback from fingers accelerated body representation update and embodiment of the ERT.