Research‎ > ‎Seminars‎ > ‎Seminars 2009‎ > ‎

10.28.2009 - Hochman on CPGs

  • V0 population of interneurons necessary for righ-left coordination in walking
  • V1 population still get locomotion, but you slow down in walking
  • V2 disrupts left-right coordination - don't get locomotion - drive commisural connections from brainstem to spinal cord
  • Hb9 interneurons activate after the motor-neurons fire
  • V3 spinal neurons also disrupt the rhythm
  • No explicit population that is necessary for the CPG, therefore the CPG is an emergent phenomena
  • How do these experiments actually work?  Does it require "feedback" for the rhythmicity? Perhaps physical enervation can help to drive the circuit?
  • Think that the CPG is in the ventral spinal cord
  • Feedback is required? Removing afferents appears to abolish locomotion.
  • Primary afferents and descending systems not required?
  • Lack of glycinergic or GABAergic transmission still has oscillation in fictive patterns
  • Lack of glutamatergic transmission still get oscillation in fictive patterns
  • Cholinergics are required for walking because flexor/extensor are coactive.
  • There appears like there is an external clock keeping time for the CPG
  • Swimming to walking consists of completely different populations of neurons in lamprays
  • The clock may come from sympathetic nervous system
  • Left then right flexor occurs with low level stimulation