𝗘𝗻𝗲𝗿𝗴𝗶𝘇𝗲𝗱 𝗼𝗿 𝗘𝘅𝗵𝗮𝘂𝘀𝘁𝗲𝗱 𝗯𝘆 𝗖𝗿𝗼𝘄𝗱𝘀? 𝗛𝗲𝗿𝗲’𝘀 𝘁𝗵𝗲 𝗦𝗰𝗶𝗲𝗻𝗰𝗲 𝗪𝗵𝘆

My next book, Silent Strength: The Introvert's Guide to Building Successful Startups, is a practical guide that empowers introverted entrepreneurs to harness their natural strengths, lead authentically, and succeed in the startup world. To provide a complete picture, I also explore the scientific differences between introverts and extroverts. This post is part of my learning.

“When in public, introverts... often feel to be

the center of (unwanted) attention, hence

rarely craving attention. Extroverts, on the other

hand, seem to never get enough attention.”

– Criss Jami

Ever wonder why some people light up at the prospect of a crowded event while others need a deep breath to calm themselves before they walk through the door?

Research shows that the difference between introverts and extroverts in these moments is actually rooted in brain chemistry.*

Before events, extroverts anticipate social interaction with excitement because it triggers activity in the dopamine reward system, which governs motivation, mood, and feelings of pleasure. Dopamine creates a sense of energy and fuels the eagerness to engage. In contrast, introverts are more sensitive to dopamine, needing only a small amount to feel its effects. As a result, the thought of extended group interaction can feel overwhelming, since dopamine builds too quickly in their systems.

During events, dopamine surges for extroverts as they socialize, making them more alert, confident, and eager for new interactions. For introverts, however, sustained stimulation can lead to overstimulation, anxiety, or fatigue. Many find themselves seeking quiet corners or short breaks to reset.

After events, extroverts often ride a lingering dopamine “high,” leaving them satisfied and energized. Introverts, by contrast, frequently experience what psychologists call the “introvert hangover,” a mental and physical fatigue caused by overstimulation. To recover, they rely on acetylcholine, another neurotransmitter that activates the body’s “rest and digest” mode. Released during calming activities like reading, journaling, or quiet reflection, acetylcholine slows heart rate, lowers blood pressure, and helps introverts restore balance and contentment.

The interplay between dopamine and acetylcholine underscores how each personality type manages stimulation differently. Dopamine fuels extroverts through external engagement, while acetylcholine rewards introverts for turning inward to process and recharge. Both systems, however, highlight valuable contributions: extroverts bring enthusiasm and social energy to events, while introverts offer depth, reflection, and thoughtful connections.

It’s also worth remembering that the body responds the same way to both eustress (positive stress) and distress (negative stress): rapid breathing, a racing heart, and a dry mouth.

The difference lies in interpretation: your mind decides whether you’re nervous or excited. So, when you feel your heart racing before meeting someone new, it may simply be your body preparing you for a valuable opportunity.

Understanding these biological differences can help you navigate gatherings more effectively and value the distinct strengths both introverts and extroverts bring to the table.

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I wrote this post with AI editing.

* Susan Cain, Quiet: The Power of Introverts in a World That Can’t Stop Talking (New York: Crown Publishers, 2012). Marti Olsen Laney, The Introvert Advantage: How to Thrive in an Extrovert World (New York: Workman Publishing, 2002). Laurie A. Helgoe, Introvert Power: Why Your Inner Life Is Your Hidden Strength (Naperville, IL: Sourcebooks, 2008). Robert M. Sapolsky, Why Zebras Don’t Get Ulcers: The Acclaimed Guide to Stress, Stress-Related Diseases, and Coping, 3rd ed. (New York: Henry Holt and Company, 2004).

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