I have been reading a lot on the subject of adult autism lately. While there isn't a lot of literature on adult ACC there are some things observed in both our populations. What is important for me to relate today is how adults, learning how to pass as an NT, how to fit in and not be noticed. One unfortunate result of this is how the skill to pass as "normal" has many of us being misdiagnosed with various disorders, (that may be co-morbid but masking the disability.) This is why many of us don't receive an accurate diagnoses until later in life...case in point I was 46 when the neurologist discovered my ACC and I was diagnosed with an ASD.
I've had to really work on my bitterness.
It's well known that early intervention can improve outcomes, the earlier on life one recognizes ACC or ASD the sooner we can teach skills to cope or even thrive as a person with a disability. I know had the doctors in my childhood had access to the knowledge about ACC and ASD we have today, my outcome would look vastly different.
The way ACC and ASD kids learn best (generally speaking, of course) is by rehersal. Actually being prompted to perform the task over and over (far more many times than for an NT.) Such things have a more profound and permanent impact on children's brains, than their adult counterparts. We know today that the nerve cells in the brain and spinal cord continue to migrate and grow well into our twenties. The brain and nervous system is by its nature more plastic, or adaptable during these years.
The downside of rehersal learning is that this is how we learned to pass, or to imitate NT behaviors, even while we don't really "understand" why we must behave this way. So on the surface, we get comments like "you don't look (insert label.)" But how would they know? The same is true for many medical professionals that are not at all versed in ACC and/or ASD. Their attention passes over HFA (high functioning autism) and the need for any ACC diagnostics. We go through the world like a billiard ball, bouncing off the walls, maybe even learning to cope outwardly, but inwardly we blame ourselves for how we are in the world because we have not been diagnosed yet. (Speaking of the many diagnosed in later life.)
This rehearsal thing has another side too. I have attended and done very well in various technical schools, the latest was becoming a Notary Public. But at no time was I able to translate these skills into a real life situation. The "conditions" present when I learned are different when I am "working" and I can't generalize them over. Many times adults with DDs perform highly on cognitive or social testing in a doctors office, while failing to be able to translate that into real life situations. Fortunately there are more doctors specially trained to identify ASD traits, for example, despite the presence of all kind of coping behaviors.
In general your typical GP-PCP knows little to nothing about ACC or ASD, and how best to relate to us and worth with us in a way we can understand and utilize. Having said that, things are progressing, just not as rapidly as I'd like to see.
Lastly, I just want to mention so that you understand, how exhausting it is to pass, we have to work very hard to do so, it is foreign to us, and I can say personally, a major source of irritation. Imagine going through life feeling one has to apologize, not even for what one does, but who one is? I for one, work diligently at being myself and shedding myself of the expectations of others. One of the most healing gifts I could give myself.