KU Leuven: Experimental hearing implant succeeds in registering brain waves

Researchers at KU Leuven have for the first time succeeded in measuring brain waves directly via a hearing implant. These brainwaves objectively indicate how good or bad someone hears. The research results are important for the further development of smart hearing aids.

An audiologist will set up the device based on the user’s input, but in some cases this is no easy feat. Just think of children who were born deaf or the elderly with dementia. It is more difficult for them to estimate and communicate how well they hear the sounds, with the result that the implant is not optimally adjusted.

A possible solution is to adjust the implant based on the brain waves, which contain information about how the person processes the sound signal. Such an objective measurement can be done via an electroencephalogram (EEG) in which electrodes are placed on the head. However, it would be more efficient if the implant itself could register the brain waves to measure hearing quality.

Experimental implant
Research by KU Leuven, in collaboration with producer Cochlear , has shown for the first time in a few test subjects that this is possible. “We used an experimental implant that works exactly like a normal implant, but with easier access to the electronics,” says postdoctoral researcher Ben Somers of the Experimental Oto-rhino-laryngology research group.

“A cochlear implant contains electrodes that stimulate the auditory nerve. For example, sound signals are sent to the brain. In our research, we have now also managed to register the brain waves that arise in response to the sound via these implanted electrodes. That is a first. An additional advantage is that, through a smart choice of measuring electrodes, we can measure larger brain responses than the classic EEG measurement with electrodes on the head. ”

“In a more distant future it should even be possible for the hearing implant to be able to adjust itself autonomously on the basis of the registered brainwaves.

An implant that can register brainwaves and measure hearing quality itself offers several advantages, adds co-author Professor Tom Francart. “First, it is an objective measurement that is independent of the user’s input. In addition, you could measure hearing in daily reality and monitor it better. In the long term, the user should therefore no longer have to be tested in the hospital. An audiologist could consult the data remotely and adjust the implant where necessary. ”

“In a more distant future it should even be possible for the hearing implant to be able to adjust itself autonomously on the basis of the registered brainwaves. We are far from that yet, but this research is a necessary first step. Based on our findings, manufacturers can now move forward with smart hearing aids that improve users’ quality of life. In addition to audiological applications, the measurement of brain waves also offers many other possibilities. Think of the monitoring of sleep, attention or epilepsy, but also so-called brain computer interfaces, where other devices can be controlled with brainwaves. ”