The Inferior Colliculus as a Site of Electrical Stimulation

Univ Of North Carolina Chapel Hill, Chapel Hill NC

Investigators

Abstract

DESCRIPTION (provided by applicant): In the last few decades, electrical stimulation of the inner ear has allowed a remarkable ability for deaf individuals to hear and understand speech. However, some patients cannot be helped by an implant placed in the ear due to the lack of auditory nerves, which can be either congenitally absent, damaged through trauma, or removed in surgery for tumors. In these patients, the only way to deliver acoustic information is through direct brain stimulation. A potential site for stimulation is the inferior colliculus (IC) in the midbrain. The IC is major site for the convergence of auditory information prior to its representation in the cortex. The current study will measure the physiological and behavioral responses to electrical stimulation of the IC in rabbits. The stimuli will include speech cues known to be discriminable by animals. The hypothesis is that patterns of electrical stimulation based on the responses of IC neurons to auditory stimuli will improve the physiological and behavioral discrimination of the speech cues compared to stimulation patterns used for cochlear implants. The experiments will test the ability to achieve functional hearing by stimulation of the inferior colliculus, a major center for auditory integration in the brain. The expected health benefits include future development of devices, software and treatments that assist the deaf and hearing impaired.