Understanding differences in outcomes of cochlear implants

Summary Deafness has a detrimental effect on the structure and function of the auditory system, from loss and demyelination of neurons in the auditory nerve, to plastic changes in the brainstem and cortical areas. These changes can have detrimental effects on a person’s ability to understand speech using a cochlear implant. Understanding the mechanisms of these changes, and how they impact on hearing, will lead to ways to optimise the cochlear implant function for each individual.

Project Details

Deafness has a detrimental effect on the structure and function of the auditory system, from loss and demyelination of neurons in the auditory nerve, to plastic changes in the brainstem and cortical areas. These changes can have detrimental effects on a person’s ability to understand speech using a cochlear implant. Understanding the mechanisms of these changes, and how they impact on hearing, will lead to ways to optimise the cochlear implant function for each individual. This research will involve planning and conducting psychoacoustic and electrophysiological experiments designed to understand the individual characteristics that limit or enhance outcomes for those who receive a cochlear implant. This project will focus on testing a recent hypothesis for a mechanism to explain poor speech understanding: that the response of the auditory neural system in such cases is inconsistent, that is, it varies over time, and this will make it difficult to detect and use the important amplitude modulations in the speech signal and to relearn how to categorise speech sounds after implantation. This hypothesis will be tested by analysing electrophysiological measurements and correlating the findings with behavioural measurements of hearing. This project will potentially lead to new clinical procedures to optimize the programming of cochlear implants for individual people.

General methods to be used in the project:
psychophysics, electrophysiology, cochlear implant programming

Suitable background of students:
This PhD project will suit a student with a background in audiology, experimental psychology, engineering, neuroscience or a related disciple. Strong computing and statistical skills (Matlab, R or related) will be an advantage.