Electrical stimulation of the auditory nerve: Single neuron strength-duration functions in deafened animals

Abstract

Destruction of cochlear hair cells initiates degenerative changes within auditory nerve fibres (ANFs), including loss of peripheral processes and demyelination of the cell body. These changes are likely to affect the biophysical processes involved in action potential generation to an electrical stimulus. We measured the strength-duration relationship in acutely deafened (100% ANF survival) versus long-term deafened cochleae (∼15% ANF survival) by recording from single neurons in the central nucleus of the inferior colliculus (ICC). Input/output functions were constructed for 22 ICC neurons in response to stimulation of the auditory nerve using biphasic current pulses of 20-1000 μs/phase. Str..