Like individuals, cultures have different styles. America is a noisy culture, unlike, say, Finland, which values silence. Individualism, dominant in the U.S. and Germany, promotes the direct, fast-paced style of communication associated with extraversion. Collectivistic societies, such as those in East Asia, value privacy and restraint, qualities more characteristic of introverts.
According to the Myers-Briggs Type Indicator personality test administered to two randomized national samples, introverts make up 50 percent of the U.S. population. The MBTI definition of introversion—a preference for solitude, reflection, internal exploration of ideas vs. active engagement and pursuit of rewards in the external/social world—correlates closely with the Big Five description. But the results still surprise; if every other person is an introvert, why doesn't the cultural tone reflect that?
It's not just that we overestimate the numbers of extraverts in our midst because they're more salient. The bias of individuals is reinforced in the media, which emphasize the visual, the talkative, and the sound bite— immediacy over reflection.
"In verbal cultures, remaining silent presents a problem," report Anio Sallinen-Kuparinen, James McCroskey, and Virginia Richmond, who have studied communication styles in the U.S. and Finland. Perceptions of competence tend to be based on verbal behavior. An introvert who is silent in a group may actually be quite engaged—taking in what is said, thinking about it, waiting for a turn to speak—but will be seen in the U.S. as a poor communicator.
When psychologists Catherine Caldwell-Harris and Ayse Ayçiçegi compared U.S. and Turkish samples, they found that having "an orientation inconsistent with societal values" is a risk factor for poor mental health. The findings support what the researchers call the personality-culture clash hypothesis: "Psychological adjustment depends on the degree of match between personality and the values of surrounding society."