I taught gifted education at a prestigious middle school for five years. Over 300 kids came through my classroom during that time. I saw it all. Seizures. Fistfights. One girl was pretty sure there were secret messages from the principal in the tests I gave. Lots of them started taking drugs early too. The culmination happened in the Fall of 2012, when one girl convinced her friends that, if they killed themselves, t…
Probably half the class or more had some form of condition, Autism, ADHD, depression, etc.
Looking back at it now, I don't think it was the case that gifted people are generally "mad". I'm a fairly normal person, and so were a lot of other people in the class. I think that rather, it was that these kids didn't integrate well into conventional education, but this gifted education class was very understanding and accepting of people's "quirks", and had a much more open learning environment where people could grow in their own way. I ended up there because I struggled with the structured nature of normal school.
I've met plenty of people over the years who could be considered gifted (in this case, top 5% IQ), most of them are completely normal and probably just dealt with the overly structured nature of normal school.