Brain-computer interfaces and neuroprostheses for severe speech impairment in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a relentlessly progressive neurodegenerative disorder that frequently culminates in severe dysarthria and anarthria, profoundly isolating patients and diminishing their quality of life. Traditional speech therapy and conventional augmentative and alternative communication devices rely on residual motor control and become ineffective in late-stage ALS. In response, brain-computer interfaces and speech neuroprostheses have emerged as transformative solutions. By decoding neural signals directly from the motor cortex and translating them into synthesized speech, these devices bypass compromised neuromuscular pathways. Recent high-impact clinical trials have demonstrated unprecedented success, achieving high-speed decoding and integrating artificial intelligence-driven voice banking to preserve a patient's unique vocal identity. However, significant translational challenges remain, including signal degradation, surgical risks, high socioeconomic costs, and ethical dilemmas regarding patient autonomy and data privacy. This perspective reviews the current state-of-the-art in speech neuroprosthetics, analyzes the barriers to widespread clinical implementation, and advocates for increased interdisciplinary collaboration and funding to establish these technologies as a standard of care for patients with severe speech impairments.