"Shyness is a normal human temperament," says lead researcher Dr. Kathleen Merikangas of the National Institute of Mental Health, whose teachers always noted her own childhood shyness on her report cards.
But just as it can be hard to tell when feeling sad turns into depression, "there is a blurred boundary between people who describe themselves as shy and clinically significant impairment," Merikangas adds.
The difference: The shy can be drawn out and adapt, while teens or adults with full-fledged social anxiety become so paralyzed during social situations that it interferes with everyday functioning.
In school-age boys especially, "shyness isn't very well tolerated in the United States," says [Children's Hospital Boston's Dr. Nancy] Snidman, who wasn't involved with the new research.
Snidman and colleagues at Harvard Medical School have tracked infants to their college years, and know that babies who react very negatively to new people and objects tend to grow into shy children. That's not a bad thing -- caution is considered an important evolutionary adaptation.
Usually, the clinging tot does just fine as he or she grows older and finds a niche, Snidman says. Girls may think the shy teen boy is nice because he's not macho, for example, or the shy kids wind up on the school newspaper so they can write instead of do public speaking. Many outgrow their shyness.
Yet a very shy child is considered more at risk than others of later developing some type of anxiety disorder -- just as the opposite extreme, a very outgoing child, can be at greater risk for attention or conduct disorders, she says.
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