Federal Project Grant Award Summary

The University of Chicago received a $705,937 Project Grant from the National Institute on Deafness and Other Communication Disorders (NIDCD) under the Research Related to Deafness and Communication Disorders program (CFDA 93.173), awarded May 1, 2026, with a completion date of March 31, 2031. This award supports multiscale investigation of vestibular signal integration in the mammalian inner ear, focusing on how different hair cell types and neural encoding strategies contribute to balance and head motion detection. The research utilizes an excised mouse utricle model to examine how Type I and Type II hair cells—which employ fundamentally different synaptic transmission mechanisms (nonquantal ion channels versus quantal glutamate packets, respectively)—process sensory information and integrate signals within vestibular afferent neurons, with particular emphasis on "dimorphic" afferents that contact both cell types.

The project delivers basic neuroscience research outputs examining cellular and population-level mechanisms of vestibular information processing across two integrated research aims. Aim 1 investigates how quantal versus nonquantal synaptic transmission modes are integrated at the individual afferent level, examining differences in frequency tuning, linearity, gain, and temporal resolution. Aim 2 extends this analysis to population coding mechanisms, exploring how zonal organization and hair cell diversity contribute to the distinct regular and irregular afferent spike patterns that encode different head motion parameters. These research activities advance fundamental understanding of inner ear sensory processing relevant to balance disorders and vestibular dysfunction.