Now the nitty gritty.
some information taken from: http://www.celebritytypes.com/blog/2011/04/the-scientific-evidence-for-introversion/
Apparently Extroverts somehow are insensitive to dopamine leading them to require a large amount. Enough that the need direct stimulation from their environment to satisfy them. The extreme would be a thrill seeker who like street racing, clubbing and that kinda thing. This needing more dopamine actually is a perfect description of someone with a smaller population of dopamine receptors.hmm.
In contrast an introvert rarely needs external stimuli to satisfy that need to feel good. Instead, thoughts, ideas, concepts, these are the thins that feel good to an introvert. This nuero-pathway uses a different hormone, Acetycholine, as its feel good hormone. In the link above it is said that introverts actually do have more dopamine in their brains and that the receptors are structurally different than in extroverts. If by structurally different they mean there are more then it would all make sense but it could mean something else.
“Extroverts need [dopamine’s] sidekick, adrenaline, which is released from the action of the sympathetic nervous systems, to make more dopamine in the brain. So the more active the extrovert is, the more Hap[py] Hits are fired and dopamine is increased. Extroverts feel good when they have places to go and people to see.”
“Introverts, on the other hand, are highly sensitive to dopamine. Too much dopamine and they feel overstimulated. Introverts use an entirely different neurotransmitter, acetylcholine, on their more dominant pathway…”
“Acetylcholine…affects attention and learning (especially perceptual learning), influences the ability to sustain a calm, alert feeling and to utilize long-term memory, and activates voluntary movement. It stimulates a good feeling when thinking and feeling.”
Now here is the thing. A person can up-regulate their dopamine receptor count by simply avoiding over stimulation of that pathway. You know how if you stop doing something your addicted to for long enough, it becomes easy to just stay off of it? that is because of an up regulation of dopamine receptors, meaning an increase in the number of them in the brain. If you eat candy all the time, nothing else tastes as good, but then if you stop eating candy for a long time, everything else eventually starts to taste better. So if the difference between an Extrovert and an Introvert was the number of Dopamine receptors, and if the change from using one “feel good pathway” to another, was activated by having a certain number of dopamine receptors, a person should be able to change from extrovert to introvert if given the time for up regulation to occur.
My hypothesis is that an extrovert, someone who was accustomed to going clubbing and street racing or just eating a lot of candy, was willing to stop doing anything very stimulating, it’s possible that they would eventually turn into an introvert and become more interested in ideas and concepts ect. They would grow more dopamine receptors to balance their needs in this area and then they would star to become more reflective.