Embodied information processing: vibrissa mechanics and texture features shape micromotions in actively sensing rats

Area of Science:

• Neuroscience
• Sensory Biology
• Biomechanics

Background:

• Peripheral sensory organs are crucial for initial sensory information transduction.
• Understanding how physical embodiment shapes sensory transduction is key to perception.
• The rodent vibrissa system is a widely used model for studying touch sensation.

Purpose of the Study:

• To characterize surface transduction during active sensing in the rodent vibrissa system.
• To investigate the role of vibrissa biomechanics in shaping sensory signals.
• To compare sensory input from rough versus smooth textures.

Main Methods:

• High-speed videography was used to track vibrissae movement.
• Rats were trained to sample both rough and smooth textures.
• Analysis focused on vibrissa motion frequencies and velocities.

Main Results:

• Vibrissa length variation predicted motion mean frequencies, highlighting biomechanical influence (e.g., resonance).
• Rough surfaces induced large amplitude, high-velocity "stick-slip-ring" events.
• Smooth surfaces generated smaller, regular stick-slip oscillations, with both exceeding velocities from reduced preparations.

Conclusions:

• Embodiment plays a critical role in vibrissal sensing.
• Active sensation generates more robust sensory drive than previously predicted.
• Input transformations by sensory organs are vital for neural representation.