Interpretation of spontaneous spike discharge patterns of neurons in the cochlear nucleus

Experimental studies with microelectrodes have resulted in quantitative statistical descriptions of spike discharge patterns of both cochlear nucleus neurons and the cochlear nerve fibers that innervate them. A renewal stochastic process provides a useful descriptive model for the discharge patterns of cochlear nerve fibers in the absence of acoustic stimuli. If it is assumed that the total input to a neuron is a superposition of many of these renewal processes, it is possible to derive discharge patterns for the neuron, given the way the neuron responds to its inputs. For some neurons in the anteroventral cochlear nucleus (AVCN), a model which assumes that the neuron discharges each time an input discharge occurs appears to be adequate. Certain other neurons, found in the posteroventral cochlear nucleus (PVCN), have discharge patterns compatible with the assumption that each discharge requires the accumulation of a number of input discharges. These findings are consistent with the anatomy of neurons in these two regions. Some extensions and generalizations of the modeling techniques used are presented.