The Myers-Briggs Guide for Writers

Chapter 3: E vs. I

Extraversion and introversion.  One of the most famous personality dynamics in modern culture.  Most people who hear either of these words can probably call to mind some image of what each represents.  Extraverts are social people; they love to talk, they love to party, they love to rally, and they love drama.  Introverts are quiet souls; they adore a good book, they thrive off cancelled plans,  they try to escape from reality, and they hate leaving their rooms.  It seems pretty cut-and-dried.

Except it's not.

The introvert-extravert continuum does not measure sociability, agreeableness, anxiety, success, or intelligence.  In fact, it does not measure any personality trait.  So throw out any ideas you had about what it means to be an introvert or an extravert (this is going to be a common theme); the truth of the matter is that the only difference between an introvert and an extravert is where they get their energy.

Extraverts glean energy from social interaction.  This does not mean that they are inherently more social creatures; there are "shy" extraverts just like there are "outgoing" introverts.  It doesn't even necessarily mean they love crowds or parties; it just means they feel revitalized when externally stimulated, whatever that means for them.  My brother, for instance, loves to make jokes; the more people laugh, the more energy he has to make more jokes.  As such, it takes a few seconds for him to scroll through his list of Snapchat friends.

Introverts, on the other hand, glean energy from solitude.  While they have a certain capacity for social interaction, after a point they will begin to feel depleted.  As an introvert myself, I can attest to this; I can tread water at a party for a couple hours, but then, all at once, I'll begin to sink.  After that, it's a hopeless cause trying to get me to interact with others; I just don't have the energy.  I also don't have a Snapchat.

But my brother and I are by no means "typical".  I once had a math teacher who I was dead sure was an introvert.  He talked in front of the class, sure, and was a huge jokester, but he always carried around a sense that his inner world was far richer than the one he shared with us.  So imagine my surprise when I managed to get him to take the Myers-Briggs... and he and my brother scored the same.  That was my reality check; I realized then that stereotypes really don't apply to anybody.

Now that you understand the difference, though, some of you may be asking: why are there introverts and extraverts?  Why do some people gain energy from social interaction, while others need time alone to recharge?

Well, the best analogy I've ever heard explaining the purpose, if not the cause, of both types compares them to producers and consumers.  It worked something like this:

Introverts make their own energy.  When they have time alone to recharge, they replenish themselves, making them basically self-sufficient.  Extraverts, on the other hand, get energy from other people; consequently, introverts, with their theoretically infinite ability to create energy (given the right circumstances), transfer their energy to extraverts in social situations, then going home to replenish themselves again.  In this way, both groups get the energy they need, the introverts are kept from perpetual isolation, and extraverts are kept from being constantly around others, since the introverts need time to recharge.

Of course, the real world is much more complicated than that; there are hermits who haven't spoken to another human being in years, and there are incredibly anxious people who can't stand to be alone for any length of time.  Extraverts talk to other extraverts, and introverts talk to other introverts.  The producer-consumer analogy isn't meant to be perfect; it's meant to make the dynamic easier to understand.

Still, the analogy doesn't explain the cause of introversion and extraversion.  That is where things get very interesting.  Studies have shown that introversion and extraversion, while influenced by the environment, have an actual, physical cause: introverts' and extraverts' brains use different pathways to react to internal or external stimulation.  Huffington Post submitted an article (originally from QuietRev.com) explaining three of these differences:

First, dopamine.  Dopamine is a neurotransmitter, which is a chemical that moves through the brain's nervous network, causing a certain response.  This particular neurotransmitter has been linked to movement, attention, and learning and is a part of the brain's reward network.  It is what your brain floods with when your crush says they like you back, when you get that A on the math test you studied for, when you score that final goal and win the game.  Introverts and extraverts, however, react differently to dopamine.  While they both have the same amount available, when introverts release dopamine in response to one of these events, they begin to feel overstimulated.  Meanwhile, their extravert friends get a rush of excitement and clamour for more.

Introverts get excited over a different neurotransmitter: acetylcholine, or ACh.  ACh has been linked to muscle action, learning, and memory.  It also rewards the brain for looking inward, for thinking deep thoughts, for focusing intensely.  Thus, introverts prefer quiet environments where they can enjoy the ACh high: curled up with a good book, watching ten consecutive seasons of their favorite TV show, or sitting in their living rooms, writing guides about the Myers-Briggs for aspiring authors.  Extraverts, having already gotten an extreme dopamine high, have no need for this ACh release.

Drawing these two things together is the autonomic nervous system.  Comprised of the sympathetic and parasympathetic systems, this is the system that prepares you for action in the face of danger or excitement, then calms you down afterwards.  The sympathetic nervous system releases epinephrine, or adrenaline, from the adrenal glands, ramping the body up for a fight-or-flight response.  This system has been linked to dopamine, so extraverts love it.  Their heart rate increases, their brains hyper-focus, and their digestive systems slow as more energy goes into making them as alert as possible.

Introverts, on the other hand, favor the parasympathetic nervous system, which releases norepinephrine, or noradrenaline, to calm the body down.  They appreciate this; their heart rate and blood pressure decrease, their muscles relax, and they begin to store energy.  This system, which has been linked to ACh, provides the sense of peace and deep thought that introverts thrive on.

To sum up, because of their brain chemistry, extraverts operate on a lower level or internal arousal; they need stimulation from their environments in order to keep from feeling bored.  Conversely, introverts operate on a higher level of internal arousal; their minds are constantly stimulated, so anything that comes from the outside runs the risk of overstimulating them.  Notably, this does not mean introverts are in any way more intelligent than extraverts.  There is little-to-no correlation between the two factors.

But what does all this mean for the Myers-Briggs?  Before we get to that, this and the next several chapters must give you a stronger knowledge base about the eight traits that form the sixteen personalities.  Afterwards, we will put it all together and provide an overview of the types.  Finally, we will explain the cognitive functions and really delve into the reasoning behind each type.  That's where the introvert-extravert dichotomy will become especially important.

That being said, I suggest you begin looking around now and trying to determine--without using stereotypes--whether your friends and family are introverts or extraverts.  Then ask them and check your accuracy.  It is an interesting exercise that will make things much easier for you later.

As you people-watch, also be thinking about your characters.  Where do they find their energy?  Play around with it.  You could create a character who is concerned mainly with the outside world--who focuses mainly on people and events and things, not their thoughts--but is shy or withdrawn.  Or you could create a talkative character who loves to socialize and has plenty of friends, but who always needs time to recharge at the end of the day.

Remember: there are more than two kinds of people in the world.  Making your character an extravert or an introvert does not doom them to a life of constant interaction or perpetual isolation.  Just like there are billions of different people in the world, there are billions of ways to make your character love, hate, or ignore his or her surroundings.

Bibliography:

Granneman, Jennifer. "The Scientific Reasons Why Introverts And Extroverts Are Different." The Huffington Post. TheHuffingtonPost.com, Inc., 15 Dec. 2015. Web. 14 June 2016.