Voice-following hearing aid both reads and stimulates the brain
Even in noisy environments, most of us are able to understand what another person is saying by "focusing" our hearing on their voice. Although regular hearing aids are currently unable to do so, that may change if a new prototype reaches production.
The ability to mentally follow a select person's voice, while filtering out distracting background noise, is known as the "cocktail party effect." With a few experimental exceptions, hearing aids aren't able to replicate it, as they simply amplify all of the sounds in a room equally.
Working with industry and academic partners, scientists at Germany's Fraunhofer Institute for Digital Media Technology set out to address that problem via the three-year mEEGaHStim research project – "mEEGaHStim" stands (roughly) for "mobile EEG-based brain stimulation for better hearing."
The resulting wearable device does indeed incorporate an EEG (electroencephalograph), which analyzes the electrical activity of the wearer's brain in order to determine the direction in which they're currently focusing their hearing. An integrated directional microphone known as a beamformer responds by focusing itself in that same direction, while simultaneously filtering out noises coming from either side.
At the same time, via a technique called transcranial electrostimulation, the wearable uses a very low electrical current to stimulate the auditory cortex of the user's brain. According to Fraunhofer, this helps improve the intelligibility of the speaker's voice.
The present prototype, which takes the form of a headset, has reportedly been successfully tested on non-deaf volunteers. Plans now call for trials on partially-deaf users, and for the technology to be miniaturized into something more akin to a traditional hearing aid.