Dwayne D. Simmons
Department of Physiological Science

The mechanisms of hearing disorders that involve sensorineural connections within the inner ear and brainstem are not well understood. Research in our laboratory is concerned with the establishment and subsequent modification of sensorineural connections during the development and regeneration of the auditory system across species. In the mammalian auditory system, we are investigating neurochemical factors that may influence cholinergic and GABAergic synaptogenesis. Our studies of the developmental expression of cholinergic receptors and synthetic enzymes suggest that neurotransmitters are expressed after synapses are established. Additionally, synaptic competition may influence the distribution of synapses seen in adults. In the amphibian auditory system, we are investigating sensorineural regeneration as a model for sensory specific synaptogenesis.