An extrovert and introvert walk into a bar. It’s a Saturday night, so the place is hopping. A cover band croons away on stage while dozens of people stand in groups, clutching drinks and nearly shouting to be heard.

The extrovert takes in the scene and gets excited. He sees social opportunities everywhere — an attractive woman at the bar, friends to talk to, the chance to cut loose and have fun. He walks straight up to his group of friends, slaps one of them on the back, and orders a beer.

The introvert sees the situation very differently. He hangs back for a moment, looking around, taking everything in. Then he walks quietly up to his friends. He feels overwhelmed, drowning in all the noise and activity, but he tells himself to relax — this is supposed to be fun, after all.

And the introvert does have fun for a while. But it doesn’t last.

Soon the introvert grows tired. Really tired. Not only does his body feel physically fatigued, but his mind becomes foggy and slow (and not just from the drinks). He desperately wants to head home — or at least outside — where it’s quiet and calm, and he can be alone. He’s getting an introvert hangover.

He glances over at the extrovert, who’s still chatting away with his friends. He doesn’t show any signs of slowing down. In fact, the extrovert looks even more energized than when they arrived.

Sound familiar?

If you’ve ever felt exhausted from socializing, there’s a very real reason. Here’s the science behind why socializing is draining for us “quiet ones” — it has to do with our unique wiring as introverts.

A Few Caveats

First, let’s get a few things out of the way. The above scenario is just an example, and a generalization. Not every extrovert spends their weekend partying, and sometimes even we introverts live it up, too. We all act introverted at times and extroverted at others; according to Carl Jung, the founder of analytical psychology, there’s no such thing as a “pure” introvert or extrovert. We all fall somewhere on the sliding scale that defines introversion and extroversion.

Another thing. Socializing is actually draining for everyone eventually. A recent study from the University of Helsinki found that participants reported higher levels of fatigue three hours after socializing — whether they were an introvert or an extrovert. How tired they felt depended on a few factors: how many people they’d met, the intensity of the interaction, and how much they had a particular goal in mind.

It makes sense that both introverts and extroverts would feel tired after socializing, because socializing expends energy. You have to talk, listen, and process what’s being said, among other things.

Nevertheless, there are some very real differences between introverts and extroverts.

Introverts, Extroverts, and Rewards

These differences have to do with rewards. Rewards are things like getting the phone number of an attractive stranger, getting promoted at work, or even eating a delicious meal.

We all enjoy rewards. We all want rewards. But introverts and extroverts react differently to them.

To understand why socializing quickly wears out introverts, I spoke with Colin DeYoung, a psychology professor at the University of Minnesota, who recently published a paper on introversion. I was doing research for my book, The Secret Lives of Introverts. DeYoung, like other experts, believes that extroverts have a more ramped-up dopamine system than introverts.

What Is Dopamine?

Dopamine is a neurotransmitter. It helps control certain functions by sending signals between the body and the brain. Sometimes called the “feel-good hormone,” it’s associated with positive emotions like bliss, euphoria, and concentration. Dopamine plays an important role in a range of body functions, from movement to sleep to mood. When you feel pleasure — like eating your favorite foods or even during sex — your brain releases dopamine.

There can be a dark side to dopamine. It’s associated with addiction. Some illegal recreational drugs, for example, work by stimulating its release and increasing the amount of it in the brain, which is how people get hooked. That’s how powerful dopamine is.

Extroverts Have a More Active Dopamine System

So what does this have to do with socializing?

Because extroverts have a more active dopamine system, they’re more excited by the possibility of reward. Dopamine gives them energy to, say, strike up a conversation with a stranger or hang out at the bar until last call. Even though these things are tiring, dopamine reduces their cost of effort. It’s like getting a shot of espresso before running a race.

Dopamine even explains why extroverts might talk louder, faster, and with more confidence. These are ways to drawn more attention to yourself and position yourself to gain social rewards.

Introverts have dopamine, too, but our dopamine system is not as “turned up” as that of an extrovert. We just aren’t as “hooked” on pursuing the things that extroverts chase.

Having a less active dopamine system also means that introverts may find certain levels of stimulation — like loud noise and lots of activity — to be punishing, annoying, and tiring. It explains why the introvert in the bar scenario was ready to escape after a while.

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The Introvert’s Superpower

Introverts don’t seek rewards to the same degree that extroverts do. Is this a bad thing? In my opinion, no. It’s actually the introvert’s superpower.

We all have that one friend who partied too hard and paid a price. Or the workaholic spouse who compromised her health and relationships. These are people who chased rewards — hard.

Instead of looking for outside status, introverts tend to turn inward. They research a topic simply for the joy of learning something new. Job-wise, they seek a calling that is more than just a paycheck. They desire depth and intimacy in their relationships, a connection that is mind-to-mind and heart-to-heart, rather than an abundance of casual acquaintances.

I’m not saying all extroverts are shallow and all introverts are deep. That’s simply not true. Sometimes extroverts pursue quiet, intrinsically rewarding activities; sometimes introverts seek status and other external rewards. A healthy, successful life for anyone should include a mix of both.

When writing my book, I asked introverts to tell me about the things that motivate and energize them. They all mentioned low-key activities, like a solo shopping trip, a meaningful conversation with a friend, finishing a good book, or expressing themselves through art. If it weren’t for the introvert’s less active dopamine system, introverts wouldn’t be doing these activities as much. The introvert’s way isn’t about chasing rewards, but rather about seeking meaning.

Want to learn more? Check out my book, The Secret Lives of Introverts: Inside Our Hidden World.

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Image credit: @adamkuylenstierna via Twenty20

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