So I read these studies many years ago and search engines have notably become worse since then but I'll do my best.
Not gay to ask, btw, what's gay is appealing to corrupt authorities and acting like their say so is the final word on reality, which is why it's a meme.
This
article contains a lot of relevant information and sources. It's a great place to start. Some of the other points can be inferred from the info in this article.
For example, if smart people do poorly in school due to a lack of sufficiently stimulating material, it makes sense that this would manifest as symptoms of ADHD, since they would have trouble paying attention. If smart people have trouble communicating with most people, it makes sense that this would manifest as symptoms of autism, since it would result in social difficulties. So the correlation between the two and high IQ makes sense. So from a logical standpoint, you can see the over lap.
Though there are studies that also support this separately, like this one that claims
autism is a high IQ disorder or this one that claims
higher IQ are at more risk of ADHD.
In regards to the low IQ and high IQ both disagreeing with midwits, my guess is because low IQ people struggle parsing the propaganda that captures the midwits, so they rely on their gut feeling that runs contrary to the lies they're being told. High IQ people can also side step midwit targeted propaganda and logically end up at the same conclusions that low IQ people come to through their gut feeling.
Speaking from personal experience, prior to getting red pilled, I used to consciously dismiss my gut feeling in favour of rationalisations that were based on the information I had available to me. I did it out of misguided principle, as I always valued truth and wanted to only take into account concrete information and not emotional feelings when forming an opinion. It took many examples of being proven wrong for me to reconsider my stance and humble myself in regards to what ones gut feeling or intuition truly is. It's not an emotion like the kind that makes women cry when they get overwhelmed. It's a subconscious way of communicating information to our conscious self, sans references. It requires faith for you to trust it, but should you trust it, you'll find that time and time again it's always right. At least in my experience. So there's something more to it that we don't understand, yet low IQ homies aren't bothered by this problem of not consciously understanding or making sense of everything so they're happier to just accept it and go with it.