MATURATION OF SINGLE AUDITORY-NERVE FIBERS RESPONSES TO TONE-BURST STIMULATION IN KITTENS

  • 1 January 1975
    • journal article
    • research article
    • Vol. 70  (2) , 129-138
Abstract
The maturation of single auditory nerve fiber responses to long-duration (500 ms) tone-bursts was studied in kittens at various stages after birth. Spike discharges were examined as a function of latency, peristimulus histograms (PSTH) and interval histograms. The mean value of the on peak latency was about 25 ms at 1-3 days after birth. It then regressed, reaching 8-12 ms at the end of the 1st wk, and 2-4 ms at 20 days. The evolution of PSTH revealed a characteristic sequence of unit reactivity to long duration stimuli (i.e., on, rhythmic, and continuous responses). Rhythmic responses may be related to the immaturity of synaptic junctions below the hair cells. The interspike interval histograms of the discharges showed a similar evolution. A bimodal distribution corresponding to the rhythmic mode of reactivity, appeared at the end of the 1st wk.