Patients with severe paralysis and aphasia, such as those with ALS, may have normal cognition but cannot motorically produce speech.

“So a lot of the work that we've done is on people that have a severe form of paralysis. and ephasia we typically I see refer to as someone who's got let's say a stroke y um in the language centers of the brain where we've focused recently is on patients that have a severe form paralysis like ALS so there the problem is they have largely normal language but they can't get those can't get the motor signal out can't get the motor signal out to the vocal tract the lips the tongue the jaw the larynx those descending fibers are severely affected by ALS they degenerate.”