Related Experiment Video
Updated: Aug 14, 2026

Postsynaptic Recordings at Afferent Dendrites Contacting Cochlear Inner Hair Cells: Monitoring Multivesicular Release at a Ribbon Synapse
Published on: February 11, 2011
Transmitter release in inner hair cell synapses: a model analysis of spontaneous and driven rate properties of
R Schoonhoven1, V F Prijs, J H Frijns
1Leiden University Hospital, Department of ENT/Audiology, The Netherlands. r.schoonhoven@ent.medfac.leidenuniv.nl
Abstract:
The inner hair cell (IHC) synapse is one of the stages of cochlear processing that determine the relation between sound pressure level and spike rate in auditory nerve fibres. Transmitter released in the non-stimulated condition is held responsible for the wide range of spontaneous spike rates (SR) observed in these fibres. Properties of stimulated spike activity in auditory nerve fibres, including rate threshold and operating range of a fibre, are known to systematically vary with SR. This paper presents a model analysis of the relation between IHC transmembrane potential and transmitter release rate as becoming manifest in these spontaneous and driven rate properties. A previously developed computational model is used to identify those transfer properties of its synapse section which lead to reproduction of the variation of rate thresholds, shapes of rate-intensity functions and maximal driven rate with SR known from the literature. First a simple additive release model, in which driven transmitter release depends linearly on IHC potential, is elaborated. Its results lead to the hypothesis that the true release function is non-linear and variable across synapses generating different SR. An exponential release function is then introduced, with parameters varying across SR in a physiologically dictated way. This approach leads to adequate reproduction of the variation in rate thresholds and rate-intensity functions with SR. Finally, the model is applied in an inverse way to directly estimate the release function from given rate-intensity functions. The conclusion of both forward and inverse model analyses is that transmitter release is a non-linear function of IHC potential which, by the systematic variation of its parameters across SR, effectively leads to the physiological variation in dynamic range across fibres of different SR. Possible relations of these results with ultrastructural morphology and basic physiology of IHC synapses are discussed.
More Related Videos
09:35Investigating Outer Hair Cell Motility with a Combination of External Alternating Electrical Field Stimulation and High-speed Image Analysis
Published on: July 18, 2011
13:04Combined Recording of Mechanically Stimulated Afferent Output and Nerve Terminal Labelling in Mouse Hair Follicle Lanceolate Endings
Published on: May 7, 2016
Related Concept Videos
Hair Cells
The Cochlea
Action Potential
Membrane potential in neurons
Neurons typically have a resting membrane potential of about -70 millivolts (mV). When they receive...
Excitatory and Inhibitory Effects of Neurotransmitters
Auditory Pathway
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
Neuronal Communication