NBB Seminar Series

Tuesday, June 17, 2025 at 11:00am

The seminar will be In-Person.

Susan Shore, Ph.D.

Professor Emerita of Otolaryngology, Physiology, & Biomedical Engineering, University of Michigan

“Reversing pathological neural plasticity to treat tinnitus.”

Abstract:

The dorsal cochlear nucleus is the first site of multisensory convergence in mammalian auditory pathways. Principal output neurons, the fusiform cells, integrate auditory nerve inputs from the cochlea with somatosensory inputs from the head and neck. After noise exposure, fusiform cells exhibit increased spontaneous activity and cross-unit synchrony, physiological correlates of tinnitus. Underlying mechanisms include homeostatic and timing-dependent plasticity. To reverse the pathological plasticity, we delivered repeated bisensory auditory-somatosensory stimulation to guinea pigs with tinnitus, choosing an inter stimulus interval known to induce long-term depression (LTD). The LTD inducing bisensory (but not unimodal auditory) stimulation reduced physiological and behavioral evidence of tinnitus in the guinea pigs. Next, we applied the same bisensory treatment to human subjects with tinnitus using a double-blinded, sham-controlled, crossover study. The LTD inducing bisensory stimulation reduced both tinnitus loudness and intrusiveness. Unimodal auditory stimulation did not deliver either benefit. Bisensory auditory-somatosensory stimulation that induces LTD in the dorsal cochlear nucleus may hold promise for suppressing chronic tinnitus, which reduces quality of life for millions of tinnitus sufferers worldwide.