A new brain-controlled hearing system isolates a single conversation in real time, offering a practical benefit for users in noisy environments.
Researchers at Columbia University's Zuckerman Institute have developed and tested a brain-controlled hearing system that can isolate and amplify a single conversation in a noisy environment in real time. The findings, published in Nature Neuroscience, provide the first direct evidence from human studies that such a closed-loop system can provide a practical benefit to the user.
System Functionality
The system uses electrodes surgically implanted in the brain to monitor neural activity from the auditory cortex while a person listens to multiple overlapping conversations. Machine-learning algorithms analyze the timing of brain wave patterns and match them to the rhythm of a specific voice. When a target speaker is identified, the system adjusts the audio output by amplifying that speaker's volume and suppressing the volume of other speakers.
Clinical Testing
The device was tested on epilepsy patients who had electrodes pre-implanted in their brains as part of their medical treatment. In experiments, the system demonstrated the ability to:
- Correctly identify the attended speaker.
- Improve speech intelligibility for the target conversation.
- Reduce the listening effort reported by participants.
- Function effectively both when participants were guided toward a specific speaker and when they freely chose which conversation to follow.
Context and Limitations
Conventional hearing aids and cochlear implants amplify all sounds in the environment without distinguishing between voices. This research builds on a 2012 discovery that brain wave patterns can indicate which speaker a person is focusing on.
The study has several limitations. The system has only been tested on a small number of participants with typical hearing abilities who were undergoing epilepsy treatment.
Researchers noted that brain signals in individuals with hearing loss may be weaker, potentially affecting accuracy. A wearable, non-invasive version of the technology has not yet been developed. Further studies are required to test the system's performance in more complex, real-world environments.
Collaborating Institutions
The research was conducted in collaboration with surgeons and patients from Hofstra Northwell School of Medicine, Feinstein Institutes for Medical Research, NYU School of Medicine, and the University of California, San Francisco.