The Origin of the Low-Frequency Microphonic in the First Cochlear Turn of Guinea-Pig

Hear Res. 1989 May;39(1-2):177-88. doi: 10.1016/0378-5955(89)90089-0.


Low-frequency microphonic potentials (100 Hz to 2000 Hz) have been measured in the first turn of the guinea pig cochlea before and after a variety of manipulations of the cochlea. These included ablation of the apical turns, iontophoresis of streptomycin, dc current injection into the first turn, acoustic trauma and two-tone interference with pure tones. These manipulations indicate that the low-frequency microphonic measured in the first turn and at the round window is generated predominantly by the hair cells of this region. It is a convenient and relatively uncomplicated indicator of the integrity of the mechano-electrical transduction process of these cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acoustic Stimulation
  • Action Potentials / drug effects
  • Animals
  • Auditory Fatigue / physiology
  • Auditory Threshold / drug effects
  • Auditory Threshold / physiology*
  • Cochlea / physiology*
  • Cochlear Microphonic Potentials*
  • Electric Stimulation
  • Evoked Potentials, Auditory*
  • Guinea Pigs
  • Hair Cells, Auditory / drug effects
  • Hair Cells, Auditory / physiology*
  • Hair Cells, Auditory / surgery
  • Round Window, Ear / drug effects
  • Round Window, Ear / physiology*
  • Streptomycin / pharmacology
  • Vestibulocochlear Nerve / physiology*


  • Streptomycin