Printed in The Netherlands RESPONSES FROM THE FIRST ORDER NEURONS OF TH E HORIZONTAL SEMICIRCULAR CANAL IN THE PIGEON
نویسنده
چکیده
The discharge patterns of the primary vestibular afferents of the anesthetized pigeon were studied. The mean resting discharge of these cells is similar to that reported for mammals. Neurons varied with respect to rate and regularity of resting discharge. It was found that the higher the mean rate the more regular the resting discharge. Depolarizing currents directly applied to the ampulla of the horizontal canal decrease the coefficient of variation (C.V.), indicating greater regularity of response, while hyperpolarizing currents increase the C.V. indicating greater irregularity of the response. Similar results were obtained with caloric stimulation directly applied to the canal. Rotational stimulation was used to study changes in sensitivity of the cells when its discharge level was biased by means of caloric or galvanic stimulation. Some cells showed an increase in sensitivity as the biased rate was increased by galvanic stimulation and a decrease as the biased rate was decreased. The same relationship held for caloric stimulation. Other cells showed the reverse relationship.
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