I read an article in Scientific America and it showed a graph beginning with the '80's
Prior to and up to 1980 there was no diagnosis of Autism in the United States.
I think that there are times we clump children together when they seem to follow a certain pattern of behavior.
When I was born the doctor used forceps which caused lack of oxygen to the brain.
When I was 12 months they told my parents I had a form of cerebral palsy but all the doctors believe they made a mistake but they had to " label" me because I wasn't crawling or standing.
In Autism it's well known there is a test thy do on the unborn child. They use the amniotic fluid to test for he fragile x gene which appears more in boy than girls
I've taught more boys with Autism Spectrum Disorder than girls and the boys are very different than girls. Most boys at the higher end of the spectrum are very verbal where as the girls aren't.
I believe there is a difference between Autism and Autism Spectrum Disorder because given the use of the word " spectrum" means its not truly Autism but yet it falls in the area somewhere.
They used to do that with cerebral palsy which affects different areas of the brain as does Autism which seems to affect the part of the brain that processes auditory and sensory stimuli.
Sorry but this stuff gets me excited. The brain is magnificent.
My sisters and I all got boosters when we were kids and none of us developed Autism nor did any of our family or friends.