Evidence of plasticity in the pontocerebellar conditioned stimulus pathway during classical conditioning of the eyeblink response in the rabbit

Behav Neurosci. 1998 Apr;112(2):267-85. doi: 10.1037//0735-7044.112.2.267.

Abstract

Electrical stimulation thresholds required to elicit eyeblinks with either pontine or cerebellar interpositus stimulation were measured before and after classical eyeblink conditioning with paired pontine stimulation (conditioned stimulus, CS) and corneal airpuff (unconditioned stimulus, US). Pontine stimulation thresholds dropped dramatically after training and returned to baseline levels following extinction, whereas interpositus thresholds and input-output functions remained stable across training sessions. Learning rate, magnitude of threshold change, and electrode placements were correlated. Pontine projection patterns to the cerebellum were confirmed with retrograde labeling techniques. These results add to the body of literature suggesting that the pons relays CS information to the cerebellum and provide further evidence of synaptic plasticity in the cerebellar network.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Brain Mapping
  • Cerebellar Nuclei / anatomy & histology
  • Cerebellar Nuclei / physiology
  • Cerebellar Nuclei / surgery
  • Cerebellum / anatomy & histology
  • Cerebellum / physiology*
  • Cerebellum / surgery
  • Conditioning, Eyelid / physiology*
  • Electric Stimulation
  • Extinction, Psychological / physiology
  • Fluorescent Dyes
  • Matched-Pair Analysis
  • Memory / physiology
  • Nerve Fibers / physiology
  • Neural Pathways / anatomy & histology
  • Neural Pathways / physiology
  • Neuronal Plasticity / physiology*
  • Pons / anatomy & histology
  • Pons / physiology*
  • Rabbits
  • Sensory Thresholds / physiology
  • Statistics, Nonparametric

Substances

  • Fluorescent Dyes