A high-performance speech neuroprosthesis
F.R. Willett, E.M. Kunz, C. Fan, D.T. Avansino, et al.
For: researcher
The problem
People with advanced ALS who have lost intelligible speech lack a communication method approaching the rate of natural speech.
Method
Four intracortical microelectrode arrays were implanted in speech-production areas of a participant with ALS; neural activity was recorded during attempted speech (vocalized and silently mouthed) and decoded to text with a probabilistic model and a large-vocabulary language model.
Result
The interface achieved a 9.1% word error rate on a 50-word vocabulary (2.7x fewer errors than the prior state of the art) and 23.8% on a 125,000-word vocabulary — the first successful large-vocabulary demonstration.
Why it matters
The first practical demonstration of an intracortical BCI restoring near-natural communication to someone who has lost intelligible speech.
Limitations
Results are from a single participant undergoing invasive implant surgery, require intensive daily calibration, and the two implanted arrays did not contribute equally.