I remember reading about a study that determined there was a biological difference in terms of how "introverts" and "extroverts" (using your definitions) proces

I remember reading about a study that determined there was a biological difference in terms of how "introverts" and "extroverts" (using your definitions) processed information. The nervous system of the introverts processed information along a slower pathway, and through a different route, but more thoroughly. If I can manage to track down that URL, I will update my comment. "Introverted" and "extroverted" refer to the external behavioral differences that one can use to categorize people. "Introvert" and "extrovert" are different terms and more refer to people's mental focus, or Jung's explanation of where they get their mental energy. But you can't conflate the two. The most talkative person I've known classified himself as a introvert. I, on the other hand, can be extroverted, but I don't particularly like people nor do I get so much out of interacting with them that I feel compelled to be extroverted. In other words, "introverted extroverts" are the shy people - "introverted introverts" don't really give a damn. But the OP's article is certainly useful; I'd say he just needs to be more precise about the terms he uses and how it's primarily about the behavioral aspects of interacting with people. The idea that it is "draining" to use underdeveloped skills made sense to me.