Saturation of Receptor Currents Accounts for Two-Tone Suppression

  • G. K. Yates
  • C. D. Geisler
  • R. B. Patuzzi
  • B. M. Johnstone
Part of the NATO ASI Series book series (NSSA)


In a preceding paper of this symposium (Patuzzi et al., this volume), evidence was given of an intimate connection between the electrical activity of the outer hair cells (OHCs) and the threshold sensitivities of primary fibers in the neighborhood of the OHCs. Small reductions in the responsiveness of the OHCs (as indicated by small reductions in the magnitudes of the locally recorded cochlear microphonic potentials) were used, through presumed high-gain active feedback processes, to account for large reductions observed in the neural thresholds near the characteristic frequencies (CFs) of the fibers. In this paper we will present evidence that the “two-tone rate suppression” (2TRS) which is observed in the response discharges of these primary fibers is a natural consequence of the limited dynamic range of the electrical drive to these same active processes: that is, a saturation of feedback (cf. Zwicker, 1979).


Hair Cell Outer Hair Cell Cochlear Microphonic Synchronization Signal Single Tone 
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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • G. K. Yates
    • 1
  • C. D. Geisler
    • 1
    • 2
  • R. B. Patuzzi
    • 1
  • B. M. Johnstone
    • 1
  1. 1.Department of PhysiologyUniversity of Western AustraliaNedlandsAustralia
  2. 2.Departments of Neurophysiology and of Electrical & Computer EngineeringUniversity of Wisconsin-MadisonMadisonUSA

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