An introvert is often thought of as a quiet, reserved, and thoughtful individual. They don't seek out special attention or social engagements, as these events can leave introverts feeling exhausted and drained. They aren't one to miss a social gathering, and they thrive in the frenzy of a busy environment.

Around one-third to one-half of all people in the world are introverts. Though it looks different in everyone, introverts have many of the same patterns of behavior.

Introverts focus on meaning

Everybody needs a little “me” time. The difference between introverts and extroverts here is that the former group is energized by spending time alone, whereas the former feel as if they’re in a social draught, yearning for someone—anyone—just to say hi or interact with them.

Introverts would rather be in a quiet environment, than at a party.

One biological theory explains that introverts naturally have high cortical arousal (the speed and amount of brain activity) and may process more information per second. Therefore, introverts tend to avoid highly active environments. If you place them in a busy environment, their brain will quickly overload and shut down to stop the inflow of information. This is why introverts wind down at the end of the day - to recharge that lost energy.

Quiet Doesn't Mean Shy

People sometimes make the mistake of thinking that just because a person is quiet, it also means the person is shy. It is important to realize that there is a big difference between introversion, shyness, and social anxiety. Introverted people are not necessarily apprehensive about talking to others, although some introverted people certainly do experience shyness or social anxiety.

Introverts have a vivid imagination

Introverts are great at creativity and problem solving. Some of the most well-known introverts are: J. K. Rowling and Bill Gates. The downside to this, is that introverts may get stuck in their heads. They tend to over-analyze both positive and negative events. They replay the memories continuously in their mind, over and over again. 

Introverts have thicker grey matter in the pre-frontal cortex (abstract thought and decision making).

Buckner (2012) discovered that introverts have larger, thicker gray matter in their prefrontal cortex while extroverts had less. He concluded that this may be evidence for the introverted tendency of sitting alone and reflecting upon things thoroughly before making a decision, and extroverts’ ability to live in the moment and take risks without fully thinking everything through.

Extroverts pay more attention to human faces.

Studies have suggested that introverts respond to faces in a similar way they they respond to images of flowers. Extroverted brains however, show a stronger response to faces. This could be due to their social interactions, something which introverts find difficulty being in.

This also suggests that human faces hold more importance to extroverts, which could explain why they seek out other people's company.