Carly Fleischmann is a pretty famous severely autistic girl. She's non-verbal, but when she was 11 years old, she started typing.
And this article
seems apropos, as she explains it in her own words.
Side by side with her twin sister, Taryn, it would be easy to dismiss Carly as intellectually challenged. That is, until you ask her a question. For instance, Why do autistic kids cover their ears, flap their hands, hum and rock?
Carly: “It’s a way for us to drown out all sensory input that over loads us all at once. We create output to block out input.”
Carly’s brain, unlike most of ours, is overwhelmed by the senses of sight, sound, taste, smell and touch. She calls it audio filtering.
Carly: “Our brains are wired differently. We take in many sounds and conversations at once. I take over a thousand pictures of a person’s face when I look at them. That’s why we have a hard time looking at people. I have learnt how to filter through some of the mess.”
This part is a little funny in context: “I think people get a lot of their information from so-called experts but if a horse is sick, you don’t ask a fish what’s wrong with the horse. You go right to the horse’s mouth.”