Interplay of tactile and motor information in constructing spatial self-perception

Area of Science:

• Neuroscience
• Perception Science
• Robotics

Background:

• Space perception theories often focus on sensory receptor topography or motor command intensity.
• The relationship between motor commands and sensory feedback is crucial for spatial awareness during movement.
• Understanding the primary driver of spatial perception requires disentangling active versus passive movement roles.

Purpose of the Study:

• To determine whether motor commands or sensory feedback plays a primary role in spatial perception.
• To investigate how active versus passive movements differentially affect the integration of sensorimotor information.
• To re-evaluate classical theories of space perception in light of new experimental evidence.

Main Methods:

• Developed robot-mediated self-touch experiments involving active and passive movements of the right hand.
• Decoupled the spatial extent of hand movements from tactile consequences on the left forearm.
• Utilized unpredictable spatial gain factors during stroking movements to assess perceptual judgments.

Main Results:

• Movement extent and tactile extent perception significantly interfered with each other.
• This mutual interference was consistently stronger during active movements than during passive movements.
• Voluntary motor commands demonstrated a greater integration of multiple sensorimotor signals.

Conclusions:

• Voluntary motor commands play a critical role in integrating sensorimotor signals for personal space perception.
• Active movements lead to a more robust perception of personal space compared to passive movements.
• Findings challenge classical theories by highlighting the dominant role of integrated sensorimotor processing.