Extroverts are more responsive to high-intensity and "happy" stimuli, which may be why an extrovert gets frustrated at the less "readable" face of the introvert.

Extroverts are more attuned to social rewards, so they are more likely to flash a smile for effect. A notable exception are introverts - like me - whom I call "socially accessible" introverts. We have been trained well to smile and nod, which can place a burden on our processing efforts.

Some findings reveal extroverts as more adept at reading nonverbal cues, and attribute this to the extrovert's greater interest and experience with social interactions. Another line of research using subliminal images of facial emotion found introverts to be more sensitive to the differences, and hypothesized that this may be why introverts regulate the amount of incoming social information.

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.

As an introvert, you can be your own best friend or your worst enemy. The good news is we generally like our own company, a quality that extroverts often envy. We find comfort in solitude and know how to soothe ourselves. Even our willingness to look at ourselves critically is often helpful.But, we can go too far. We can hoard responsibility and overlook the role others play. We can kick ourselves when we're down. How many times have you felt lousy about something, only to get mad at yourself for feeling lousy?

A good rule of thumb is that any environment that consistently leaves you feeling bad about who you are is the wrong environment.

Though introverts are drained by interaction, we can take immense pleasure in watching the scene around us.