Wonderful Engineering

New Brain Implant Can Translate Your Thoughts Into Words

People who are unable to communicate owing to an injury or brain injury might be able to speak again soon. We say this because a team of scientists has shown off an incredible implant that is capable of decoding words using the person’s thoughts. A variety of neurological conditions can cause the patient to become unable to speak, and many are then limited to communication devices that make use of head or eye movements for spelling out the word.

However, a team of researchers at the University of California, San Francisco, have created ‘synthetic’ speech thanks to an implant that carries out a scan of brain signals of volunteers while they read about a hundred sentences aloud. The team has, however, stressed again and again that the technology is in its early stages. But it does possess the potential of providing speech to mute patients.

The team, whose study has been published in the journal Nature, didn’t try to translate the electrical activity to speak directly. It made use of a three-stage approach. The first phase was asking volunteers to read out sentences while an implant on the brain’s surface carried out monitoring of neural activity while the sound’s acoustics were being recorded.

In the second phase, the team transformed the signals representing the physical movement that is required for speech – articulations of the jaw, mouth and tongue – before they were transformed into synthetic sentences.

In the third phase, the volunteers were asked to identify the words and sentences that were a result of the computerized speech. The recordings are a little fuzzy, but the simulated sentences are mimicking the ones spoken by the volunteers so precisely that some of the words can be understood without a shadow of a doubt. The experiment was carried out with those who can speak. However, the team learned that the speech could be synthesized form participants that only mimed the sentences as well.

Edward Chang, the study’s lead author, said, ‘Very few of us have any idea of what’s going in our mouths when we speak. The brain translates those thoughts into movements of the vocal tract, and that’s what we’re trying to decode.’ This paves the way for an implant that is capable of translating brain activity into words of the patients that are unable to speak but know how to speak.

Gopala Anumanchipalli, the co-author of the study, said, ‘We used sentences that are particularly geared towards covering all of the phonetic contexts of the English language. But they are only learned so they can be generalised from.’ The researchers have also found a ‘shared’ neural code among the participants suggesting that parts of the brain that are triggered while trying to articulate a word or phrase are the same in everyone.

Chethan Pandarinath and Yahia Ali, from the Georgia Institute of Technology, Atlanta, said, ‘With continued progress, we can hope that individuals with speech impairments will regain the ability to freely speak their minds and reconnect with the world around them.’