title: Summating potential (SP) tuning curves.
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.
mesh_terms: D000200:Action Potentials; D000818:Animals; D001489:Basilar Membrane / Q000502:physiology; D003051:Cochlea / Q000502:physiology*; D003055:Cochlear Microphonic Potentials; D005072:Evoked Potentials, Auditory; D006168:Guinea Pigs; D006198:Hair Cells, Auditory / Q000502:physiology; D010470:Perceptual Masking; D013199:Stapes / Q000502:physiology; D000159:Vestibulocochlear Nerve / Q000502:physiology*