Whisker-based spatial cognition in mice

Area of Science:

• Neuroscience
• Somatosensation
• Sensory processing

Background:

• Object localization is well understood in visual and auditory systems.
• The neural mechanisms for tactile object localization in external space are unclear.
• Whiskers are crucial for tactile exploration in rodents.

Purpose of the Study:

• To investigate how tactile inputs from whiskers are transformed into a percept of object location in mice.
• To determine the spatial acuity and characteristics of whisker-based tactile localization.
• To explore the role of the primary somatosensory cortex in tactile spatial judgments.

Main Methods:

• Developed a whisker-based categorization task for head-restrained mice.
• Required mice to judge object positions in the horizontal plane.
• Analyzed spatial acuity, bias, and generalization across whiskers, objects, and hemispaces.

Main Results:

• Mice achieved submillimeter spatial acuity in object localization.
• Spatial judgments were robust and showed minimal bias relative to the category boundary.
• Mice demonstrated generalization of learned spatial categories to novel positions.
• Tactile localization depended on the whisker-related primary somatosensory cortex.

Conclusions:

• Mice construct a robust percept of object location using their whiskers.
• This tactile perception is not tied to specific sensors or stimulus features.
• Whiskers support sophisticated tactile localization in external space, independent of specific sensory inputs.