[Properties of the acoustic neurons of the dorsal nucleus of the medulla oblongata in the frog Rana ridibunda].

Studies have been made of the spontaneous activity and ipsilaterally evoked impulsation in single cells of the medullary auditory region of the frog Rana ridibunda. Approximately 70% of the neurones in the dorsal nucleus exhibited spontaneous firing with an average frequency from 1 to 40 imp/s. Distribution of intervals between impulses (excluding the shortest ones) was found to be close to exponential. Ipsilateral tonal burst presentation at the optimal frequency for the neurones investigated may produce the following types of response: "primary-like" "chopper" and phasic. In tonic neurones, the function of the expected impulsation rate (which reflects the dynamics of synaptic potentials) usually satisfactorily reproduces the initial portion of the stimulus envelope. Phase locking was observed in some of the neurones for tonal signals at frequencies lower than 0.8-1.0 kHz.