In the 1960s, Hans Eysenck added to Jung's ideas. He thought the main difference between introverts and extraverts lies in how they recharge their mental energy. 

Some experts state that extraverts and introverts use different brain areas to form their ideas. An extravert relies on short term memory and can come to fast associations and ideas. But they often speak before they think.

Carl Gustav Jung coined the terms introversion and extraversion in the 1920s. According to Jung:

Good teachers are aware of the differences between extraverts and introverts and try to develop their strengths.