From Revenge of the Introvert in Psychology Today:
Introverts are not driven to seek big hits of positive emotional arousal—they'd rather find meaning than bliss—making them relatively immune to the search for happiness that permeates contemporary American culture. In fact, the cultural emphasis on happiness may actually threaten their mental health. As American life becomes increasingly competitive and aggressive, to say nothing of blindingly fast, the pressures to produce on demand, be a team player, and make snap decisions cut introverts off from their inner power source, leaving them stressed and depleted. Introverts today face one overarching challenge—not to feel like misfits in their own culture...
To Hell With Happiness
In the United States, people rank happiness as their most important goal. That view has a special impact on introverts. Happiness is not always their top priority; they don't need external rewards to keep their brains in high gear. In fact, the pursuit of happiness may represent another personality-culture clash for them.
In a series of studies in which subjects were presented with an effortful task such as taking a test, thinking rationally, or giving a speech, introverts did not choose to invoke happy feelings, reports Boston College psychologist Maya Tamir. They preferred to maintain a neutral emotional state. Happiness, an arousing emotion, may be distracting for introverts during tasks. By contrast, extraverts reported a preference to feel "happy," "up," or "enthusiastic" and to recall happy memories while approaching or completing the tasks.
At this year's meeting of the Society for Personality and Social Psychology, Tamir, along with Iris Mauss of the University of Denver, presented a paper entitled, "Come On, Get Happy: The Ironic Effects of the Pursuit of Happiness." The two did not specifically study introverts or extraverts. What they discovered is that, for all people, the pressure to be happy actually reduces happiness.
"We found that when we prime people to value happiness more, they become more unhappy and depressed," reports Mauss. "Our findings offer an intriguing explanation for the vexing paradox that even in the face of objectively positive life circumstances, nations generally do not become happier."
The priming effect seen in the study parallels the social priming introverts experience in everyday life. Although introverts like pursuing frontal cortex functions associated with the exploration of meaning, "there are cultural pressures that could make one feel guilty for not wanting to be as happy as the culture dictates," says Tamir. As a result, introverts are hit with a double whammy—feeling less happy, then feeling guilty and inadequate for feeling that way.
With a biological makeup that enables them to see positive emotional stimuli as a distraction when they are focused on another task, introverts are good at resisting all distraction. Using functional brain imaging, Stanford biopsychologist Brian W. Haas measured the reaction time for introverts and extraverts when they tried to identify the color in which an emotionally provocative word was printed. Introverts proved more able to focus on the task of color identification while disregarding the emotional content and had significantly better reaction times. Concludes Haas: Introverts, who exhibit a higher resting state of arousal, "don't need the same kind of outside entertainment."