We researched autism in psychology.

It's quite rare for someone with autism to be able to comprehend that he/she has it and be able to communicate and function at a regular rate, like a normal healthy person. Autism is a brain disorder and the neurons in the brain are affected, so they don't transmit messages properly. That can affect the other parts of the brain that help you think ahead, regulate coordination, reason, control emotions, etc.

Autism can be diagnosed in an adult if it isn't the most common and obvious form. Autism also doesn't always happen in the womb. Your brain grows and develops your whole life and gives you a large amount of time for the neurons not to grow properly or to grow in the wrong place. However it isn't common for that to happen and it usually does happen before birth.

I see you've watched Rain Man. I was going to reccomend it to anyone here who wants to know more about autism.