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James C Saunders"Synaptic basis of neuronal adaptation in the chick cochlear hair cell"

Abstract :


Adaptation is a common property of all sensory systems, and is seen as decreased sensitivity to constant stimulation.
Adaptation in the auditory nerve roccurs when the large discharge rate at stimulus onset is followed by an exponential decay in activity as stimulus duration continues. Unlike adaptation in the deeper regions of the CNS, discharge activity in the auditory nerve declines to a steady but sustained level. In this presentation the parameters of rapid, short-term and long-term adaptation in the cochlear nerve of the chick are presented as a function of frequency, intensity, and temperature. The time constant for recovery from adaptation is also presented. Data are then presented that describe the responses of voltage gated calcium channels and vesicle pools at synaptic ribbon release sites during hair cell membrane depolarization, The physiology of neural adaptation at the chick hair cell afferent synapse is most likely determined entirely by the rates of release and replenishment of various neurotransmitter vesicle pools in the hair cell.

Didier Dulon