Motor Speech Disorders Laboratory

Cochlear Implant Psychophysics Laboratory

Julie Bierer

Lab Overview and Current Projects:

Human psychophysical studies: My lab is evaluating the effects of partial tripolar fractions on threshold, loudness, and psychophysical tuning curves. The partial tripolar electrode configuration is a novel and potentially clinically useful mode of stimulating cochlear implants. It is a hybrid between the broadly activating monopolar and the more focused tripolar configurations. Focal electrode configurations activate a restricted and local population of auditory neurons. Cochlear implant channels most and least sensitive to the most focal stimulus, the tripolar electrode configuration, will be studied to demonstrate the range of effects possible with the partial tripolar configuration.

Modeling studies: We are developing a practical model of cochlear implant activation of the auditory nerve in the presence of varying nerve survival and/or distance between the electrode and nerve. The long-range goal is for audiologists to have a tool to map the cochlear implant electrode relative to viable nerve cells with the threshold measures.

Animal physiological studies: The partial tripolar electrode configuration, relatively novel to the field of cochlear implants, will be characterized by neural activation patterns of the central auditory nervous system using multi-channel recording.