Learning-induced multiple synapse formation in rat cerebellar cortex

Neurosci Lett. 2002 Nov 8;332(3):180-4. doi: 10.1016/s0304-3940(02)00759-0.


Strengthening of synaptic connections has been proposed to underlie information storage in the brain, and experience-dependent increases in synapse number have been observed. However, the effect of these new synapses on the specific connectivity, and thus function, of a given brain area remains largely unknown. We report here that motor learning specifically induces the formation of multiple synapses--two post-synaptic contacts at a single pre-synaptic varicosity--in the cerebellum. Rats undergoing motor learning had more multiple synapses (two Purkinje cell spines contacting a given parallel fiber varicosity) per Purkinje cell than did active or inactive controls. The formation of multiple synapses provides an additional connection between a given parallel fiber and Purkinje cell, thereby enhancing particular pathways, and may constitute a fundamental mechanism of neural encoding.

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
  • Cerebellar Cortex / physiology*
  • Learning / physiology*
  • Male
  • Motor Activity / physiology
  • Motor Skills / physiology
  • Neuronal Plasticity / physiology
  • Purkinje Cells / physiology
  • Rats
  • Rats, Long-Evans
  • Synapses / physiology*