Principles governing recruitment of motoneurons during swimming in zebrafish

Nat Neurosci. 2011 Jan;14(1):93-9. doi: 10.1038/nn.2704. Epub 2010 Nov 28.


Locomotor movements are coordinated by a network of neurons that produces sequential muscle activation. Different motoneurons need to be recruited in an orderly manner to generate movement with appropriate speed and force. However, the mechanisms governing recruitment order have not been fully clarified. Using an in vitro juvenile/adult zebrafish brainstem-spinal cord preparation, we found that motoneurons were organized into four pools with specific topographic locations and were incrementally recruited to produce swimming at different frequencies. The threshold of recruitment was not dictated by the input resistance of motoneurons, but was instead set by a combination of specific biophysical properties and the strength of the synaptic currents. Our results provide insights into the cellular and synaptic computations governing recruitment of motoneurons during locomotion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / physiology
  • Animals
  • Motor Neurons / physiology*
  • Recruitment, Neurophysiological / physiology*
  • Spinal Cord / physiology
  • Swimming / physiology*
  • Synaptic Potentials / physiology
  • Zebrafish