The “cocktail-party problem” is nothing to do with deciding whether to have that third G&T. It’s about picking out voices in the crowd. Our brains have the ability to zoom in on conversations to which we want to pay attention, even against loud background noise. But from our mid-30s the nerves in our inner ear start to become less sensitive and the signal to the brain’s auditory centre becomes muddied, making it harder to pick out particular sounds. Researchers at Columbia University are working on what they reckon will be the first brain-controlled hearing aid to restore that ability.
Brain control isn’t as futuristic as it sounds. It works by using electrical sensors to pick up traces of nerve activity known as myoelectric signals. The same technology has been used in cochlear implants to restore hearing, most often to deaf children, since the early 1980s. But the Columbia team is doing something different. They have figured out how to zoom in on particular voices by decoding nerve signals from the brain to determine which voices the user is trying to pay attention to.
The system works by detecting brainwaves and subjecting them to an algorithm. The algorithm looks for statistical regularities in a large dataset to determine which parts of the dataset – in this case a mixture of sounds – belong together. The electronics in the hearing aid then amplify the parts of the sound spectrum that correspond to the parts the algorithm has picked out.
The goal is not only to improve our hearing but to reduce cognitive load on people in noisy situations, which should help people who work in industrial surroundings. It’ll also help you enjoy a cocktail party more, and stay long enough to enjoy that third G&T. In that case, it might be a mixed blessing. Stuart Nathan•