While it is widely accepted that the precise timing of action potentials is essential for normal auditory function in areas such as the auditory nerve and the medial superior olive, spike timing in pyramidal neurons of the dorsal cochlear nucleus has not been studied extensively. It is known that these neurons show temporal fidelity to complex sounds; however, the ability of these cells to fire precise and reliable trains of action potentials has not been investigated. Since pyramidal cells form the major output of the DCN and integrate both auditory and non-auditory information, it is our hypothesis that these neurons could utilize spike timing to encode this information. Pyramidal cells also receive timed inhibition, a characteristic that is imperative for timing in other areas of the brain. We hypothesize that there are specific biophysical and synaptic characteristics of these cells that would enable them to utilize spike timing to encode information. These characteristics include a fast inactivating potassium channel, a persistent sodium channel, and timed inhibitory input from interneurons. We will employ a variety of techniques to test our hypothesis that these characteristics affect the timing of action potentials in a response to a current pulse. ? ?
Street, Sarah E; Manis, Paul B (2007) Action potential timing precision in dorsal cochlear nucleus pyramidal cells. J Neurophysiol 97:4162-72 |