Manipulation-specific cortical activity as mice handle food.

Area of Science:

• Neuroscience
• Motor Control
• Sensorimotor Integration

Background:

• Food handling presents a complex motor task for studying manual dexterity.
• Understanding the neural basis of forelimb movements during natural behaviors like food handling is crucial.

Purpose of the Study:

• To investigate the relationship between cortical activity and forelimb movements during food handling in mice.
• To explore the role of sensorimotor cortical areas in fine motor control during a natural behavior.

Main Methods:

• Recorded high-speed video (1,000 fps) and multi-channel electrophysiological cortical spiking activity in mice during food handling.
• Decomposed oromanual events into submovements for event-aligned analysis of neural activity.
• Used optogenetics to manipulate forelimb M1 neuronal activity and assessed effects on movement.

Main Results:

• Forelimb M1 activity was modulated during food handling, increasing during manipulation and decreasing during holding.
• Optogenetic manipulation of M1 neurons affected food-handling movements.
• Similar oromanual-related activity was observed across forelimb M1, S1, and lateral M1, with distinct temporal profiles.
• Cortical activity in these areas accurately predicted forelimb position, indicating high information content.

Conclusions:

• Cortical activity during food handling is manipulation-specific, distributed across sensorimotor areas, and contains rich kinematic information.
• Sensorimotor cortical areas exhibit both shared and distinct neural representations of forelimb movements during complex manual tasks.