Hindbrain modules differentially transform activity of single collicular neurons to coordinate movements

Area of Science:

• Neuroscience
• Motor Control
• Computational Neuroscience

Background:

• Coordinated movements, like swatting or gaze shifts, require precise neural control.
• Current models propose transforming overall desired displacement into individual body part displacements.

Purpose of the Study:

• To investigate the neural logic underlying coordinated movements in the mouse gaze system.
• To explore how single neurons contribute to the control of multiple body parts during movement.

Main Methods:

• Electrophysiological stimulation of the superior colliculus (SC) in mice.
• Analysis of evoked head and eye movements.
• Tracing neural pathways from SC to brainstem nuclei (medulla and pons).

Main Results:

• Stimulating the SC evoked head movements with stereotyped displacements.
• SC stimulation also elicited eye movements with stereotyped endpoints.
• Individual SC neurons with branched axons project to distinct brainstem modules controlling head and eye movements.

Conclusions:

• The mouse gaze system employs a unique neural logic, departing from the overall displacement model.
• Single neurons specify a mixture of endpoints and displacements for different body parts.
• Motor commands are computed at distinct anatomical stages, revealing a hierarchical motor control system.