Activity map of a cortico-cerebellar loop underlying motor planning

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Motor Control

Background:

• The neocortex and cerebellum are known to interact for cognitive functions.
• The precise organization of these structures into functional networks for specific behaviors is not well understood.

Purpose of the Study:

• To delineate the neural activity supporting motor planning.
• To investigate the relationship between this activity and the mesoscale cortico-cerebellar connectome.

Main Methods:

• Utilized transneuronal tracing to map connectivity between the anterior lateral motor cortex (ALM) and the cerebellum.
• Conducted cerebellum-wide neuronal activity surveys during a motor planning task (directional licking).
• Performed perturbation experiments to assess the necessity of identified cerebellar regions.

Main Results:

• Discovered divergent and largely open-loop connectivity between the ALM and cerebellum.
• Identified specific cerebellar 'hotspot' regions with enriched preparatory activity and conjunctive input-output connectivity to the ALM.
• Demonstrated that these conjunction regions are essential for maintaining preparatory activity and guiding subsequent movement.

Conclusions:

• The study identifies a functional cortico-cerebellar loop critical for motor planning.
• Suggests that the cerebellar cortex selectively establishes reciprocal connections with the ALM to orchestrate motor planning.