BU wins $2.75M grant from NIDCD to test and refine prototype Visually Guided Hearing Aid

Boston University (BU) College of Health & Rehabilitation Sciences: Sargent College was recently awarded a five-year, $2.75M grant from the National Institute on Deafness and Other Communication Disorders (NIDCD) to test and refine a prototype Visually Guided Hearing Aid (VGHA).

Gerald D. Kidd Jr., professor in the department of speech, language & hearing sciences at BU Sargent College and director of BU's Sound Field Laboratory developed the VGHA prototype in collaboration with an international research team and Malden, Massachusetts-based Sensimetrics Corporation.

According to the NIDCD, 17 percent of Americans have hearing loss in one or both ears, and the prevalence of hearing loss increases with every age decade. For the majority of hearing losses that are not medically remediable, a hearing aid is the only viable treatment. However, only about 1 in 5 people who could benefit from hearing aids actually wear them. One reason, according to Kidd and colleagues, is that even the most sophisticated modern hearing aids come with a fundamental challenge: how to selectively amplify the sounds the listener wishes to hear while excluding unwanted, interfering sounds.

"Typical hearing aids may not help much in some situations," says Kidd, a psychoacoustics specialist. "They amplify everything, even those voices and sounds you want to tune out."

The VGHA is a new approach to hearing aid design that combines focused amplification with the selection of a sound source by the listener. This unique design uses eye gaze as the means of steering directional amplification, combining an eye-glasses-mounted eye-tracker with an acoustic beam-forming microphone array. The VGHA senses direction of gaze using the eye tracker, and an interface converts those values into control signals that steer the acoustic beam. These technologies work together to approximate the human ear's ability to choose what to tune into and what to ignore, essentially solving the "cocktail party problem".
"We can't turn our heads as quickly as we turn our attention," explains Kidd. "The VGHA addresses these problems by using eye movement - which is quicker than head movement - to steer the hearing aid's microphones like an acoustic flashlight that you shine on what you want to listen to."

The team's preliminary speech intelligibility measurements with noise and speech maskers revealed near or better than normal spatial release from masking with the VGHA. While not yet a wearable prosthesis, the VGHA is ultimately planned as a portable, wearable device.