Summating potential (SP) tuning curves.

M A Cheatham; P Dallos

doi:10.1016/0378-5955(84)90009-1

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Summating potential (SP) tuning curves.

M A Cheatham·P Dallos

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Abstract

Two methods were used to extract frequency specific information from the gross d.c. cochlear potential, the summating potential (SP). The first approach was to derive SP tuning curves using a two-tone simultaneous masking procedure; the second to obtain SP iso-response functions. The influence of various parameter changes on the configuration of these functions was also investigated. While SP tuning curves measured using the two-tone paradigm have higher Q10 dB values than SP iso-response functions in the base of the cochlea, the latter have the advantage of avoiding contamination by various nonlinear phenomena which are inherent in the simultaneous tone-on-tone masking procedure. Since SP tuning curves are similar to those for basilar membrane motion (Sellick, P.M., Patuzzi, R. and Johnstone, B.M. (1982): J. Acoust. Soc. Am. 72, 131-141) and the whole nerve action potential (AP) (Cheatham, M.A. and Dallos, P. (1979): J. Acoust. Soc. Am. 65, S13), nearly the same degree of tuning may be reflected at these peripheral recording locations.

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Action Potentials Animals Basilar Membrane Cochlea Cochlear Microphonic Potentials Evoked Potentials, Auditory Guinea Pigs Hair Cells, Auditory Perceptual Masking Stapes Vestibulocochlear Nerve Journal Article Research Support, U.S. Gov't, P.H.S.

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M A Cheatham, P Dallos. 1984. Summating potential (SP) tuning curves.. https://doi.org/10.1016/0378-5955(84)90009-1

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