While American culture tends to love the extrovert—the outgoing, charismatic, confident, sociable personality—in recent years, the value of the focused, deep-thinking, quiet, listening introvert has gained favor. Unfortunately, negative stereotypes of both temperaments persist. Research is revealing that both extroverts and introverts have unique and valuable attributes that may largely be driven by genetics and brain function.
INTROVERSION, EXTROVERSION, AND BRAIN TYPES
Whether you have introverted or extroverted tendencies depends in part on your brain. After analyzing blood flow and activity patterns on more than 300,000 brain SPECT imaging scans, the team of psychiatrists at Amen Clinics has identified 5 primary brain types: Balanced, Spontaneous, Persistent, Sensitive, and Cautious. Several of these brain types are associated with attributes commonly seen in introversion and extroversion.
Introversion
Introverts are more likely to have the sensitive brain type (associated with being deeply feeling and empathic and having a tendency for low moods or depression) or the cautious brain type (associated with being prepared, risk-averse, and anxious).
Brain SPECT imaging indicates that sensitive types have high activity in the limbic system, or emotional centers, of the brain, and cautious types have too much activity in the basal ganglia. An Amen Clinics study on the neurobiological underpinnings of introversion and extroversion also revealed higher levels of brain activity in introverts in several other brain regions, including the anterior cingulate gyrus, temporal lobes, and parietal lobes.
The parietal lobes are located in the top back part of the brain and are responsible for sensing the world. Sensory information—sights, sounds, scents, and so on—can be overwhelming and put introverts into sensory overload. Thus, introverts need alone time to decompress and re-energize. They need quiet to concentrate, are reflective, self-aware, take their time to make decisions, are comfortable in their own company, prefer to write than talk, may not like working in a group, and are drained after social activity or being in a crowd.
Extroversion
Extroverts are more likely to have the spontaneous brain type, which is associated with being adventurous and creative. SPECT scans show this brain type is associated with low activity in the
prefrontal cortex (PFC). This mirrors the findings of Amen Clinics’ study mentioned above, which showed that extroverts had lower levels of overall brain activity, including reductions in the PFC. This brain type tends to run low in dopamine. Extroverts are drawn to activities (social, external reward, high sensory) that typically boost dopamine, but they may be impulsive and engage in risky behavior, such as drinking too much or participating in dangerous sports like free climbing. They are more prone to
ADD/ADHD and
addiction. An extrovert typically does not require a lot of alone time, thrives around people, enjoys wide social circles, prefers to talk out problems or questions, is outgoing and optimistic, and is not afraid to take a risk.
Research shows that these temperaments are strong and can last throughout one’s lifetime, indicating that they are likely rooted in the differential excitability of particular brain structures.
Let’s look more closely at what drives introversion and extroversion, and dispel the unhelpful myths that lack compassion and understanding.
DEBUNKING 4 MYTHS ABOUT INTROVERTS AND EXTROVERTS
Myth#1: Extroverts Are Attention-Seekers
Don’t be quick to judge an extrovert negatively. Extroverts may like being the center of attention, but it probably has more to do with brain function than self-centeredness. As mentioned above, extroverts tend to have a spontaneous brain type with low PFC activity and low dopamine. As such, they seek out external rewards that increase dopamine because they need more of it. Some
research indicates that extroverts have more dopamine receptors in their brain and are therefore less sensitive to it, increasing their need for it to feel happy. Getting attention, quick action, risk-taking, seeking novelty, talking, and socializing – these increase dopamine and its “feel good” effects.
Myth#2: Introverts Make Poor Leaders
Because extroverts seek external rewards and are outgoing, sociable, charismatic, quick thinkers, and decision-makers, they are often placed in positions of leadership. Yet, introverts make great leaders, too – and sometimes even better leaders because of the
different skills that they bring to the table – and, in part, this is due to brain function.
Unlike extroverts, research shows that the neural reward response in introverts is more sensitive to dopamine than in extroverts. In fact, one
study that observed neural reward responses in extroverts and introverts found introverts had a much more measured response to dopamine. It may be why high-dopamine experiences put introverts on sensory overload. Hence, the
y crave activities and experiences that are calming.
Additionally, experts believe that their reward response comes from acetylcholine. Its effects are more subtle, which include relaxation, alertness, and contentment. Activities like reading that call for focus and engagement of the mind make introverts feel good. The acetylcholine reward response is believed to be more involved than that of dopamine. Researcher Dr. Marty Olsen Lani, who studies the physiology underlying introverted and extroverted temperaments, posits that this acetylcholine response pathway in introverts travels through several areas of the brain, which includes regions governing empathy, self-reflection, emotional meaning, detection of errors, planning, long-term memory storage, and more.
As a result, introverts have the ability to focus for long periods, balanced and critical thinking, empathy, and an ability to quietly empower others. These introverted attributes have shown sometimes greater business success than extroverts. An
analysis of CEO performances published in the
Harvard Business Review showed that more than half of the best-performing CEOs were actually introverts!
Myth#3: Introverts Are Shy, Afraid, and Don’t Like Social Situations
An introvert’s need to retreat, think, and be alone in order to restore and re-energize is often misunderstood. A
study published in the
Journal of Neuroscience found that introverts had a larger, thicker gray matter in their PFC, which is an area of the brain associated with abstract thought and decision-making. (Interestingly, this same area is thinner in extroverts.)
This indicates that an introvert’s brain has designated more neural resources to abstract thought. They are, by nature, deep thinkers. What appears to be shyness, fear, or dislike of social situations is in reality a need to quietly think things through or assimilate a situation. Introverts prefer to listen and quietly observe, which can also be misunderstood as shyness or social awkwardness.
Myth#4: You Are Either an Introvert or Extrovert
As humans, we love to categorize and think in absolutes. We label people as introverts or extroverts, period. But experts suggest that these temperaments are a continuum. We are likely to lean towards one or the other and have a mix of introverted/extroverted traits. Although some findings suggest that our temperament doesn’t change much throughout our lives, other
research indicates that there’s a benefit to developing personality traits that do not come naturally. Introverts can bolster their happiness by participating in “extroverted” activities such as giving a presentation or socializing. Likewise, an extrovert can benefit by taking time to unwind and enjoy their own company for a time, to listen attentively, or to focus deeply on a problem. While our brain function and genetics may place us on either side of the introversion/extroversion continuum,
research shows that developing both extroverted and introverted traits may be the recipe for success.
Introverts, extroverts, and those with both traits, all have valuable gifts to offer the world, as well as brain health vulnerabilities to overcome. Identifying your brain type and temperament can be helpful to your well-being.
Depression, anxiety, and other mental health issues can’t wait. At Amen Clinics, we’re here for you. We offer in-clinic brain scanning and appointments, as well as mental telehealth, clinical evaluations, and therapy for adults, teens, children, and couples. Find out more by speaking to a specialist today at 888-288-9834 or visit our contact page
here.
