Cortical control of whisker movement

Area of Science:

• Neuroscience
• Sensory Perception
• Motor Control

Background:

• Facial muscles control whisker movements essential for tactile sensory perception in rodents.
• Cholinergic motor neurons in the lateral facial nucleus innervate whisker muscles.
• Premotor neurons in the brain stem, midbrain, and neocortex provide synaptic input to these motor neurons.

Purpose of the Study:

• To review the role of the cortex in motor control of whisker movements.
• To elucidate the neural circuits regulating whisker motor control.

Main Methods:

• Review of anatomical pathways involved in whisker motor control.
• Analysis of functional roles of cortical projections.

Main Results:

• The primary motor cortex (M1) innervates brain stem reticular nuclei, potentially forming a central pattern generator for rhythmic whisker protraction.
• The primary somatosensory cortex (S1) projects to the brain stem spinal trigeminal interpolaris nucleus, involved in whisker retraction.
• Stimulation of M1 elicits exploratory whisking, while S1 stimulation causes whisker retraction.

Conclusions:

• Distinct cortical pathways, M1 and S1, play specific roles in regulating whisker movements.
• These pathways provide insights into the neural basis of active tactile exploration.