Motor cortex can directly drive the globus pallidus neurons in a projection neuron type-dependent manner in the rat

Elife. 2019 Nov 12:8:e49511. doi: 10.7554/eLife.49511.

Abstract

The basal ganglia are critical for the control of motor behaviors and for reinforcement learning. Here, we demonstrate in rats that primary and secondary motor areas (M1 and M2) make functional synaptic connections in the globus pallidus (GP), not usually thought of as an input site of the basal ganglia. Morphological observation revealed that the density of axonal boutons from motor cortices in the GP was 47% and 78% of that in the subthalamic nucleus (STN) from M1 and M2, respectively. Cortical excitation of GP neurons was comparable to that of STN neurons in slice preparations. FoxP2-expressing arkypallidal neurons were preferentially innervated by the motor cortex. The connection probability of cortico-pallidal innervation was higher for M2 than M1. These results suggest that cortico-pallidal innervation is an additional excitatory input to the basal ganglia, and that it can affect behaviors via the cortex-basal ganglia-thalamus motor loop.

Keywords: basal ganglia; cerebral cortex; globus pallidus; neuroscience; optogenetics; rat; striatum; subthalamic nucleus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Connectome
  • Globus Pallidus / anatomy & histology*
  • Globus Pallidus / physiology*
  • Motor Cortex / anatomy & histology*
  • Motor Cortex / physiology*
  • Neural Pathways / anatomy & histology*
  • Neural Pathways / physiology*
  • Neurons / physiology*
  • Rats

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