[Responses of the units of the nerve of the frog semicircular canal to caloric stimuli of changing amplitude].

In curarized frogs, responses of isolated neural units of the lateral semicircular canal (LSC) to short local caloric stimuli of different amplitudes (0.5--12.0 degrees C over the canal temperature) inducing excitatory current of endolymph in the LSC, were studied. Estimation of maximal (peak) frequences (PF) in the responses showed the PFs in responses of 52% units (group A) to be either linearly or semilogarithmically related to peak temperature (PT). In 22% units (group B), PFs revealed saturation at PT8--12 degrees C. In 25% units (group C) PFs were related to PT first in direct and then--along with increase of PT--in reverse proportion. Duration of the group A responses is linearly for semilogarithmically related to PT. This was not observed in groups B and C. Two cases of correlation between spontaneous activity and dynamic characteristics of units from groups A and C were found. The results are in agreement with the literature references concerning data obtained in frogs using angular acceleration and stop-stimuli. The controlled caloric stimulus was concluded to be convenient for studying the dynamic characteristics of the semicircular canals afferents.