The Journal of neuroscience : the official journal of the Society for Neuroscience
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Type I spiral ganglion cells provide the afferent innervation to the inner hair cells of the mammalian organ of Corti and project centrally to the cochlear nucleus. While single-unit studies conducted over the past several decades have provided a wealth of information concerning the response characteristics of these neurons and, to some extent, their receptor targets, little is known about the neuron's intrinsic electrical properties. These properties undeniably will contribute to the firing patterns induced by acoustic stimuli. ⋯ In addition to these currents, a slow noninactivating TTX-sensitive inward current was observed that was blockable with Cd2+ or Gd3+. Problems encountered with blocking the tremendous outward K current hampered the characterization of this inward current. Similarities between the kinetics of ganglion cell currents and some of the rapid temporal characteristics of eighth nerve single-unit activity confirm the notion that intrinsic membrane properties help shape auditory neuron responses to sound.