This man with ALS is “the first power user” of a brain implant that lets him speak

Casey Harrell, a man with amyotrophic lateral sclerosis (ALS), has become the first "power user" of a brain-computer interface (BCI) that enables him to communicate and perform daily tasks. Harrell, who has been paralyzed and dependent on others for care, has accumulated over 3,800 hours of independent use of the BCI device at home within the first 22.6 months of implantation, as reported in the journal Nature Medicine. The BCI, which involves a set of electrodes implanted in his brain, was initially used to help him "speak" sentences, a capability he began using with a research team in 2023. Over the past three years, the research team, including neuroengineer Sergey Stavisky from the University of California, Davis, and Dr. David Brandman, an associate professor at the University of California, Davis, has enhanced the device's functionality. Harrell now utilizes the implant not only for communication but also for web browsing and performing his job, stating that the cumulative improvements are "truly revolutionary" for someone with his condition. The implantation surgery, which took place in July 2023, involved placing four arrays, each containing 64 electrodes, into his brain. Harrell, who was 45 at the time of the surgery and already experiencing significant muscle degeneration and speech difficulties due to ALS, volunteered for the trial, motivated by the potential for transformation in the field of assistive technology.