Extraversion - The Two Shades Of Gray

All of us know the basic distinction between introversion and extroversion/extraversion, the two extremes of the spectrum of personalities. We also know about people lying at the mid-point of this spectrum, i.e. ambiverts , people with an equal inclination towards being a social butterfly and relishing the alone-time. But there's more to it. Subsets of the personality spectrum make the whole thing a bit more interesting. That is, like introversion, extraversion too has its own types. Yes! And this actually depends on the gray matter of your brain.

This was said in a study published in the journal Cognitive, Affective and Behavioral Neuroscience by Tara White, (professor at Brown University) andErica Grodin (from National Institutes of Health). The study connected the difference in gray matter of the brains with the two different types of extraversion showed by people - agentic and affiliative.

A similar observation was made in the case of Introverts and Extroverts. Extroverts tend to respond strongly to adventures, social challenges, or taking risks, which stimulates the amygdala and the nucleus accumbens. Meanwhile, introverts tend to have larger, thicker gray matter in the prefrontal cortex — the brain region responsible for abstract thought and decision-making.

Back to the topic of two distinct kinds of extraversion, first let's see what agentic extroverts are like. These are the 'go-getters' , i.e., people who are assertive, have perseverance and a dogged determination to go forward and get what they want, doing whatever it takes. Such people are achievement-driven, therefore, take pride in winning.

The second kind, i.e. the Affiliative Extroverts are the people persons, warm and friendly to all with a great ability to play mediators and ice-breakers in conversations.

Now, studies were conducted to show the difference in gray matter in brains of people belonging to the two different domains of extraversion. The MRI scans showed this difference. People withhigher amounts of agentic extraversion measure had greater gray matter in specific regions of the brain as well as the medial orbitofrontal cortex (a small region that sits between the eyes). While, people scoring higher on affiliative extraversion showed increased gray matter only in the medial orbitofrontal cortex, not in any other regions.

The researchers still don't know the answer to whether personality traits are assigned at birth, i.e.,if certain factors spur the brain to develop this way or if it's a combination of both.

References :

1. https://www.mic.com/articles/111936/which-type-of-extrovert-are-you-the-science-behind-the-different-types-of-extroverts

2. https://www.medicaldaily.com/how-extroverted-are-you-brains-gray-matter-may-lead-two-personality-types-325064