Brain-Computer Interface Helps Paralyzed Man Speak
Imagine being unable to speak to your loved ones, your thoughts trapped inside with no way to share them. For many individuals with paralysis caused by conditions like ALS, this is their daily reality. However, a brain-computer interface (BCI) developed by researchers at UC Davis is changing that, giving new hope to those who have lost their ability to communicate.
What They Achieved
Researchers developed a BCI that decodes speech with over 97% accuracy.
A man with ALS used the device to communicate in real-time, speaking at 32 words per minute.
How It Works
The BCI works by decoding neural signals in the brain that correspond to speech. Even when someone can’t physically articulate words, their brain continues to produce signals associated with speech. By implanting small arrays of electrodes into the brain, these signals can be captured and translated into words by a computer system.
The UC Davis team, led by Drs. Nicholas Card, Sergey Stavisky, and David Brandman, tested the system on a 45-year-old man who had been living with ALS for five years. The man’s speech was severely slurred, and he relied on others for daily tasks. Using the BCI, he was able to communicate again with remarkable accuracy.
The Journey
Implantation and Calibration:
Four arrays of 64 microelectrodes were implanted in the part of the participant’s brain responsible for speech-related muscle movements. After a short calibration session where he attempted to speak 50 pre-selected words, the system decoded more than 99% of words correctly.Expanding Vocabulary:
The next day, the team expanded the vocabulary to 125,000 words. With just an additional hour and a half of calibration, the system decoded over 90% of words accurately.Long-Term Success:
Over the following months, the participant used the device in everyday conversations for a total of 248 hours. The system achieved a consistent accuracy of 97.5%, enabling the participant to speak at a rate of 32 words per minute—far faster and more reliably than previous BCIs.
Why This Matters
Communication is at the heart of human connection. Losing the ability to express yourself can be isolating and emotionally devastating. This BCI offers a transformative solution, not just for the participant in this study but potentially for thousands of others living with similar conditions.
Unlike earlier BCIs, this system requires minimal calibration and achieves unprecedented accuracy, making it more practical for real-world use. The addition of a text-to-speech system resembling the participant’s pre-ALS voice added a deeply personal touch, restoring not just the ability to communicate but a piece of the individual’s identity.
Looking Ahead
While this technology is still in its early stages, the results are incredibly promising. Researchers aim to refine the system further and explore ways to make it more accessible. Dr. Brandman sums it up perfectly: “This technology is transformative because it provides hope for people who want to speak but can’t.”
My Final Thoughts
This breakthrough is more than just a technological achievement; it’s a testament to the power of innovation and compassion. For those who’ve been silenced by paralysis, this BCI represents a new chapter—a chance to share thoughts, feelings, and words that were once locked away.
Citation: Card NS, Wairagkar M, Iacobacci C, Hou X, Singer-Clark T, Willett FR, Kunz EM, Fan C, Vahdati Nia M, Deo DR, Srinivasan A, Choi EY, Glasser MF, Hochberg LR, Henderson JM, Shahlaie K, Stavisky SD, Brandman DM. An Accurate and Rapidly Calibrating Speech Neuroprosthesis. N Engl J Med. 2024 Aug 15;391(7):609-618. doi: 10.1056/NEJMoa2314132. PMID: 39141853; PMCID: PMC11328962.