REGENERATION OF A CENTRAL SYNAPSE RESTORES NONASSOCIATIVE LEARNING

Citation
Bk. Modney et al., REGENERATION OF A CENTRAL SYNAPSE RESTORES NONASSOCIATIVE LEARNING, The Journal of neuroscience, 17(16), 1997, pp. 6478-6482
Citations number
41
Categorie Soggetti
Neurosciences
Journal title
ISSN journal
02706474
Volume
17
Issue
16
Year of publication
1997
Pages
6478 - 6482
Database
ISI
SICI code
0270-6474(1997)17:16<6478:ROACSR>2.0.ZU;2-I
Abstract
Sensitization is a form of nonassociative learning in which a strong o r noxious stimulus persistently enhances the response produced by a we aker stimulus. In the leech Hirudo medicinalis, the S-interneuron is r equired for sensitization of the shortening response. A single S-cell axon was surgically separated from its sole synaptic partner, the neig hboring S-cell, This consistently eliminated sensitization without imp airing reflexive shortening itself, as measured in semi-intact specime ns. Sensitization of the shortening reflex returned after 3 weeks when the severed axon grew and regenerated its specific electrical synapse within tile nerve cord, as shown by restored conduction of impulses b etween S-cells. This confirms the essential role of one neuron, the S- cell, in sensitization, and it demonstrates that regeneration of the s ynapse between S-cells restores this example of nonassociative learnin g.