Effect of antidromic stimulation of the glossopharyngeal nerve on afferent discharges occurring with and without sensory stimulation of the frog tongue.

Repetitive stimulation of the bullfrog glossopharyngeal nerve at a rate of 100 Hz for 10 s and at a supra-maximal intensity resulted in little depression of the glossopharyngeal nerve responses to application of quinine and mechanical taps to the tongue, in a 30-40% decrease in the responses to salt, acid, water and warmed saline and in a 80% decrease in the number of spontaneous discharges from the tongue. Such a selective depression existed throughout changes in the frequency and the duration of the antidromic stimuli. The phenomena were attributed to antidromic impulses in high-threshold glossopharyngeal nerve afferents.