AlexWelshman wrote:
Can someone with autism, who can't speak, learn to speak as an adult?
It is not quite impossible, but exceedingly unlikely. Unless the person was not speaking for reasons other than nonverbal autism, that is. For autistic nonverbal adults, the same problems are present that inhibited speech when they were a child but in addition the brain itself is now significantly less capable of learning speech. If a nonberbal autistic will ever learn to speak, it will be when they are still a child, before the age of 13-14 or so.
There are of course many other alternate methods of communication, speech is not necessary.