Yeah, Helen Keller isn't the greatest example, 'cause she *had*
vision 'til she was 2? or 4? I forget. Anyway, she had PLENTY of
processing-time to get LOTS of raw data to be able to utilize
later on in her Water moment, and plenty of stuff to analogize
to in order to increase her knowledge about her surroundings,
even if her input mechanisms were severely stifled.
Basic circuits were formed; the rest is subconscious
analogizing. Even when I learned about her in grade school, and
saw some dramatic TV movie, I wasn't terribly impressed by Helen
Keller.
I'm 1/2 deaf and 1/2 blind myself - imagining myself in her
shoes wasn't hard when I was 8, or now, but I like what she did
with her life, and I honestly was more impressed by the teacher
than by her.