Here’s an interesting idea that I haven’t heard before, courtesy of Dr. Hans Eysenck: introverts have more cortical activity than extraverts. Ergo introvert brains are already full up, which is why we avoid external stimuli. Extraverts, on the other hand, have empty brains … oh, all right, have less cortical activity, which is why they seek stimulus outside of themselves.
Dr. Hans Eysenck (1916-1997) was a popular biology-personality doctor a few decades ago. His books include The Biological Basis of Personality, Know Your Own IQ, Crime and Personality, and The Psychology of Politics.
Some great thinkers get stuck in their own theories, which can separate them from their peers. (Freud comes to mind.) Eysenck accepted only pure science. He rejected Jung and Meyers-Briggs.
To my mind, Jung and Eysenck dovetail nicely, though I’m not sure either of them would be pleased to hear it. Unfortunately, that leaves me with a chicken-and-egg problem. Does higher cortical activity cause introversion, or is it the other way around?
Whatever the answer may be, I enjoy this cortical aspect of introversion. I look forward to the day when I can refer to my personality as Super Cortical, or even Mach I Cortical. Maybe I’ll be able to turn down invitations without offending anyone, since my cortex is all booked up and it’s not my fault.