You wrote: "I did not ask about normal I asked about neurodiversity."
I think you have based your question on an erroneous assumption, but we may also have understood you. "Normal" (as a synonym for "neurotypical") is after all part of neurodiversity -- or did you mean or understand something different?
I don't think there is any evidence to suggest that introverts in general have significant genetic differences from other people to the degree which, say, people with autism or cretinism differ from the general population in terms of their chromosomes.
Some introverts have an uncommon neurological state such as Asperger Syndrome; some do not. And in some cases, the neurological abnormalities also account for extreme introversion.
Perhaps you could rephrase your question so that we can understand it better, if the answers which we are suggesting seem to you to be inappropriate responses.
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When I must wait in a queue, I dance. Classified as an aspie with ADHD on 31 March 2009 at the age of 43.