Introvert or extrovert, we can all identify with being one or the other or perhaps you shift between the two ends of the spectrum circumstantially. Either way, psychologists have been studying the fundamental qualities that make someone one or the other.
In 1960 Hans Eysenck proposed that extroverts had a slightly lower level of arousal meaning that they had to work harder to get to the level that others find normal or enjoyable therefore the need to be around others and pursue different experiences. On the other hand, introverts may experience over-stimulation and hence seek out quiet and familiar environments.
Recently, the theory has been refined to link extroversion to Dopamine a chemical that plays an important role in the part of the brain that control reward as well as novelty. A team of researchers lead by Michael Cohen tested the refined theory and confirmed the results that positively favor that introverts and extroverts processed surprise and rewards differently.
Are you an introvert, extrovert or do you find yourself in the middle of the spectrum?