I've spent the last few months trying to begin to start to initially even understand this all... but autism (with no appropriate help ever) of different "flavors" is the first thing that had ever explained many behaviors and issues with my father, mother, brother, and I guess me too.
Different countries seem to accept different diagnoses at different rates! I'm sure folks have noticed that with PTSD just a teensy bit.
I am not formally diagnosed with autism (asperger's would be closer, and female asperger's should kind of be its own category almost) but I am working on it. In my country it's very difficult to get that diagnosis officially as an adult; DSM-V requires that it be made as a kid. Well 40 years ago, definitions were very different.
I'm looking into where the info re. autism could help some of my issues... experiences like going into ptsd support groups and not being helped, never being able to cry, and lots of body issues that act differently that trauma issues would indicate... partly...
There is overlap in effects, apparently. Autism can make it hard neurologically to detect one's own feelings. A traumatic childhood with adults around who couldn't explain their own feelings can do similar things.
Loads of folks with autism apparently have ptsd. If you consider that autism is largely genetic, that may mean that both the neurology and the resulting behaviors in parents may make it difficult for kids with the same neurology to, say, learn as best they can to decode their own emotions... esp. since the prevailing understanding of emotions -- the "discourse" available that the kid might pick up around their family and outside it -- has mostly been set up by "neurotypicals", for slightly different actual brain structures from day one. To make it harder, every autistic brain is apparently wired differently from almost every other autistic brain.
This is probably a really long-term sub-thread of human experience running through human societies, mostly silently.
Well I may have lots more to post on this... maybe will start a thread...