Implanted devices have helped people with hearing loss for many years. Most of these devices stimulate the auditory nerve associated with the cochlea, a bony inner ear structure. But these kinds of implants aren’t perfect. Their performance can degrade in noisy environments, and due to conditions that damage the auditory nerve or the cochlea, many people are unable to use them. These people require a different kind of device, one that uses electrical impulses, or neurostimulation, to stimulate responses in the brain itself rather than the cochlea.
Hubert Lim, Ph.D., assistant professor in the University of Minnesota’s Department of Biomedical Engineering has been working with two colleagues, James Patrick, D.E., senior vice president and chief scientist at Cochlear Limited in Australia and Thomas Lenarz, M.D., professor and chair of the Otolaryngology Department at Hannover Medical School in Germany, to develop such a device.
Improving upon a device originally designed by Cochlear Limited, the new device enables implanting teams to more accurately control or modulate the brain’s electrical impulses that affect hearing quality. The team is also targeting a new location in the brain – the inferior colliculus (IC), a part of the midbrain that serves as a principal auditory center for the body. The IC is structured in a way that Lim believes will improve hearing better than the previous device’s location in the brainstem, the rear part of the brain contiguous with the spinal cord. Lim hopes that not only will the hearing performance gained from this device be better than the previous one but that it will be nearing that of a cochlear implant.