Sensory Attenuation With a Virtual Robotic Arm Controlled Using Facial Movements

Area of Science:

• Neuroscience
• Human-Computer Interaction
• Robotics

Background:

• Sensory attenuation (SA) is the reduced perception of self-generated stimuli.
• SA is well-documented for innate body parts, but its occurrence with extended bodies remains unexplored.
• Extended bodies, such as robotic limbs, offer new avenues for investigating self-perception and agency.

Purpose of the Study:

• To investigate whether an extended body, specifically a robotic arm controlled via facial movements in a virtual environment, induces sensory attenuation.
• To compare sensory attenuation between an innate body and an extended robotic body.
• To explore the relationship between sensory attenuation, sense of agency, and body ownership in the context of extended bodies.

Main Methods:

• Two experiments were conducted using a sound comparison task in a virtual reality environment.
• Participants controlled robotic arms with facial movements to generate audio stimuli.
• Sensory attenuation was assessed by comparing perceived intensity of self-generated vs. externally generated sounds from the robotic arm and innate body.

Main Results:

• Voluntary control of the robotic arm in a virtual environment resulted in significant sensory attenuation of audio stimuli.
• Both the innate body and the robotic arm induced sensory attenuation, but differences in the sense of agency were observed between them.
• The degree of sensory attenuation for the robotic arm was correlated with the participant's sense of body ownership.

Conclusions:

• Extended bodies, when controlled voluntarily, can elicit sensory attenuation, similar to the innate body.
• The sense of agency differs between innate and extended bodies, influencing sensory attenuation.
• Body ownership plays a role in the sensory attenuation experienced with robotic extended bodies.