Although I am not at the PG level, I am definitely introverted. But some of the characteristics described, I have usually attributed to my disability like discomfort in large crowds (I despised going into NYC for this reason), avoiding small talk, and dislike of the phone.
I work in the STEM field, and most people here skip the voicemail and turn to emails or chats - not just when they want me, but when they are looking for my team. Phone is usually used as a desperate attempt to reach the person they want at the office.
It is one of the reasons I love running and rowing - even the team boats are still to some extent, solitary (there is no talking in the boat most of the time other than by the coxswain if you are in a coxed boat). I had enjoyed team sports like volleyball, soccer - but never felt the desire to be with the team all the time outside of practice/competition.
I prefer window over aisle myself - but it is to eliminate having to deal with getting up because someone else wants to get out, and to avoid being brushed by someone walking on the aisle. But in other situations, I do tend to prefer to be close to exit route and be on the side, not in the spotlight.
My father is a classic introvert - he much rather be reading one of his favorite Shakespeare books than have to be at a dinner with even just a few people. It is to the point that when he starts dropping hints of "do you need to go shopping/do errands?", we know everyone else in the house needs to scoot - not to another room, but out of the house - for a few hours. Otherwise, he gets very irritable. One of our favorite activities to do together when I was really little was a trip to the bookstore.
