Discharge patterns of chicken cochlear ganglion neurons following kanamycin-induced hair cell loss and regeneration

R. J. Salvi, S. S. Saunders, E. Hashino, L. Chen

Research output: Contribution to journalArticle

40 Scopus citations


Hair cells in the basal, high frequency region (>1100 Hz) of the chicken cochlea were destroyed with kanamycin (400 mg/kg/d × 10 d) and allowed to regenerate. Afterwards, single unit recordings were made from cochlear ganglion neurons at various times post-treatment. During the first few weeks post-treatment, only neurons with low characteristic frequencies (<1100 Hz) responded to sound. Despite the fact that the low frequency region of the cochlea was not destroyed, neurons with low characteristic frequencies had elevated thresholds, abnormally broad U-shaped or W-shaped tuning curves and low spontaneous discharge rates. At 2 days post-treatment, the spontaneous discharge rates of some acoustically unresponsive units fluctuated in a rhythmical manner. As recovery time increased, thresholds decreased, tuning curves narrowed and developed a symmetrical V-shape, spontaneous rate increased and neurons with higher characteristic frequencies began to respond to sound. In addition, the proportion of interspike interval histograms with regularly spaced peaks increased. These improvements progressed along a low-to-high characteristic frequency gradient. By 10-20 weeks post-treatment, the thresholds and tuning curves of neurons with characteristic frequencies below 2000 Hz were within normal limits; however, the spontaneous discharge rates of the neurons were still significantly lower than those from normal animals.

Original languageEnglish (US)
Pages (from-to)351-369
Number of pages19
JournalJournal of Comparative Physiology A
Issue number3
StatePublished - Mar 1 1994



  • Cochlear ganglion neurons
  • Hair cell regeneration
  • Spontaneous activity
  • Threshold
  • Tuning curves

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Physiology
  • Animal Science and Zoology
  • Behavioral Neuroscience

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