Inner Ear Biology

Sensory hair cells of the inner ear convert mechanical vibrations into electrical impulses, which are then carried to the brain by the auditory nerve. The structure and function of the inner ear is a major focus of research at the Eaton-Peabody Laboratories. In normal ears, we study the molecular machinery that drives the transduction of mechanical to electrical signals in hair cells and the synaptic transmission of electrical signals from the hair cells to their neuronal partners. Research also focuses on the neuronal feedback system by which the brain sends control signals back to the inner ear that help us hear sounds in a noisy environment and helps protect the inner from acoustic overstimulation. 

The inner ear is the main site of the damage underlying sensorineural hearing loss (SNHL), the most common type of hearing impairment in adults. Studies here also focus on mechanisms underlying noise-induced and age-related hearing loss as well on the hearing loss associated with cancers of the VIIIth nerve (vestibular schwannoma) or with diseases of the inner ear's bony capsule (otosclerosis). 

As well as searching for treatments to prevent or slow the onset of SNHL, we are developing improved techniques for local delivery of drugs to the inner ear. We are also working on improved diagnostic tests to distinguish different types of inner ear damage using novel audiological tests or novel imaging technologies for direct visualization of inner ear structures. 

Although death of hair cells or inner ear neurons is irreversible in humans and other mammals, our researchers are investigating drug treatments and genetic manipulations to regenerate damaged inner ear tissues and restore useful hearing in animal models. Several are actively working with biotech companies intent on translating the results obtained in animal work to clinical application. One sentence descriptor: Studying the inner ear's normal function and the mechanisms underlying SNHL; developing therapies to slow or reverse the progression of inner ear hearing impairments.