Chinese researchers develop device to help 'understand' sound
Chinese researchers have developed the world’s first bionic neural device that enables the brains of hearing-impaired individuals to “understand” sound rather than merely “hear” it.
The device, created by a research team from Nankai University in the northern Chinese city of Tianjin, offers a new approach of electronic substitution and repair for hearing reconstruction, going beyond conventional cochlear implants.
“At present, cochlear implants only address the problem of ‘hearing’. However, constrained by fixed time-based signal mechanisms and a limited number of electrodes, cochlear implants still lag far behind the natural auditory system in terms of temporal resolution and speech recognition in complex acoustic environments,” said Xu Wentao, who led the research at the College of Electronic and Optical Engineering, in a Nankai University press release on Monday (13 July).
“Our goal is not only to make this system able to ‘hear’, but to enable it to truly ‘understand’ sound, meaning it can select, process and transmit valuable auditory information like natural nerves,” he said, adding that the new device marks an important step in hearing rehabilitation from ‘restoring perception’ to ‘rebuilding function’.
The study, titled ‘Artificial neuromorphic interface for hearing restoration’, was published online on 1 July in the journal Nature Materials.
According to the study, hearing depends not only on the ear but also on the auditory nerve, which acts like a ‘superhighway’ transmitting sound signals to the brain. Sensorineural hearing loss, the type of deafness caused by damage to this pathway, affects around 3 per cent of the global population.
Traditional cochlear implants can convert sound into electrical signals, but they still rely on the patient’s remaining auditory nerve to complete the final stage of transmission.
Once the auditory nerve is severely damaged or lost, “even the most advanced cochlear implant becomes ineffective”, said Xu, adding that this long-standing challenge is what his team’s breakthrough seeks to overcome.
The new device, described as a ‘neuromorphic interface’ that mimics the natural coding processes of the biological auditory nerve, integrates sound acquisition, neural coding, semantic processing and bioelectric output into a complete artificial neural circuit.
The research team explained that the device not only captures sound but also filters, analyses and encodes it in a manner resembling the natural auditory system, before conveying meaningful information to the brain.
“Going forward, we will continue our research in neural repair and bionic intelligence, and work hard to move our core technology from the laboratory to clinical use and the market,” said Xu.
“We hope to achieve more breakthroughs in neural prosthetics, intelligent healthcare, brain-computer interfaces and embodied intelligence,” he added.