Brain implants give voice to ALS patient, heralding wider speech-restoring technology
Casey Harrell, who lost his speech to ALS, now communicates through a brain-computer interface implanted at UC Davis, marking a breakthrough for voice-restoring neurotech.
After a diagnosis of ALS in 2020, Casey Harrell gradually lost the ability to move his mouth and throat, eventually becoming unable to speak. In 2023 he enrolled in a UC Davis clinical trial that placed four small electrode arrays on the left side of his speech motor cortex. The device decodes his thoughts into phonemes, assembles them into words, and displays them on a screen, with an optional synthetic voice.
Harrell now uses the system for 10-14 hours daily and has produced almost two million words, according to a June Nature Medicine report. Parallel research at the University of Michigan and by neurotech firm Paradromics is developing fully implantable, portable arrays that could enable real-time speech. Scientists caution that one outlet hardware is bulky, slow and costly, but they view it as a pivotal step toward restoring natural conversation for people with ALS, stroke, Parkinson’s disease and other speech-impairing conditions.
Why it matters
Restoring speech for people who have lost it could dramatically improve quality of life and independence for millions with neurological disorders.
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