Identification of a cellular node for motor control pathways

Nat Neurosci. 2014 Apr;17(4):586-93. doi: 10.1038/nn.3675. Epub 2014 Mar 9.

Abstract

The rich behavioral repertoire of animals is encoded in the CNS as a set of motorneuron activation patterns, also called 'motor synergies'. However, the neurons that orchestrate these motor programs as well as their cellular properties and connectivity are poorly understood. Here we identify a population of molecularly defined motor synergy encoder (MSE) neurons in the mouse spinal cord that may represent a central node in neural pathways for voluntary and reflexive movement. This population receives direct inputs from the motor cortex and sensory pathways and, in turn, has monosynaptic outputs to spinal motorneurons. Optical stimulation of MSE neurons drove reliable patterns of activity in multiple motor groups, and we found that the evoked motor patterns varied on the basis of the rostrocaudal location of the stimulated MSE. We speculate that these neurons comprise a cellular network for encoding coordinated motor output programs.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Efferent Pathways / cytology
  • Efferent Pathways / physiology*
  • Mice
  • Motor Cortex / cytology
  • Motor Cortex / physiology*
  • Motor Neurons / cytology
  • Motor Neurons / physiology*
  • Movement / physiology
  • Muscle, Skeletal / physiology
  • Nerve Net / cytology*
  • Nerve Net / physiology
  • Neural Pathways / cytology
  • Neural Pathways / physiology
  • Posterior Horn Cells / cytology
  • Posterior Horn Cells / physiology*
  • Spinal Cord / cytology
  • Spinal Cord / physiology*