Figure 3.

PADs in axonal arborizations of auditory afferents. A, Graded depolarizations tightly followed spikes recorded at the entry of the auditory nerve to the first thoracic ganglion (left). Average time course of the graded depolarization following single spikes (right). B, The afferent response to an acoustic stimulus (white noise, 1 s, 75 dB SPL) consisted of a maintained burst of spikes riding on top of a graded membrane depolarization. The asterisk highlights particularly pronounced depolarization and reduction in spike amplitude at the beginning of the response. The spike amplitude was reduced during the whole auditory response. The afferent was hyperpolarized by current injection of −2 nA.