Back to front: cerebellar connections and interactions with the prefrontal cortex

Area of Science:

• Neuroscience
• Cerebellar Function
• Prefrontal Cortex Circuits

Background:

• Limited understanding of cerebello-cerebral circuit physiology and cerebellar influence on neocortical activity during behavior.
• Recent evidence suggests closed-loop connectivity between the prefrontal cortex and cerebellum.

Purpose of the Study:

• To investigate the physiological properties of the cerebello-prefrontal pathway.
• To determine if cerebellar output modulates neocortical neuronal activity during behavior.
• To explore cerebello-prefrontal network activity during rest and locomotion.

Main Methods:

• Electrical stimulation of the fastigial nucleus (FN) in rats.
• Local field potential (LFP) and single-unit recordings in the prelimbic (PrL) medial prefrontal cortex.
• Simultaneous LFP recordings from FN and PrL during rest and active exploration.
• Granger causality analysis to assess directed network activity.

Main Results:

• FN stimulation evoked rapid LFP responses in the PrL cortex (onset latency ~13 ms).
• A majority of prefrontal neurons showed significant firing rate changes during FN stimulation.
• Significant theta-frequency (5-10 Hz) network coherence between FN and PrL was observed.
• Cerebellar to PrL Granger causality was detected during active locomotion.

Conclusions:

• Demonstrated the existence of a cerebello-prefrontal pathway in rats.
• Revealed behaviorally dependent coordinated network activity between the cerebellum and PrL cortex.
• This pathway may facilitate sensorimotor information transfer to neocortical processing during goal-directed behaviors.