The Reason Your Anxiety Actually Keeps You Alive

Americans think of anxiety as a bad thing, and for some people it truly is a bad thing.

But the common anxiety you feel about party planning, work projects, or even athletic events is not only normal, it's also beneficial.

Anxiety helps you perform better, David Barlow from Boston University's Center for Anxiety and Related Disorders told New York Magazine's Science of Us.

"The anxiety is something that motivates you to plan your approach to these challenges in such a way that you feel you're prepared," Barlow said. "In doing so, you perform at a much higher level."

It also helps us stay alive.

Anxiety developed in early humans as a way to respond to threats to safety, according to a paper by John S. Price of the U.K.'s Brighton General Hospital.

"Anxiety is a component of de-escalating strategies mediated by the paleo-mammalian (emotional) and reptilian (instinctive) forebrains," Price wrote.

Anxiety "serves to preserve the individual, just as sexual feelings serve to preserve the species," wrote Fredric Neuman, director of the Anxiety and Phobia Treatment Center in White Plains, New York, in Psychology Today.

"Fear is perhaps the easiest emotion to understand," Neuman added in his piece about anxiety's role as a survival mechanism. "In the face of an immediate danger, animals, including human beings, demonstrate a 'fight or flight' reaction. Along with the subjective sensation of fear, there occurs a complicated physiological response that serves to prepare the individual for immediate action: Muscles tense, respiration and heart rate increase, blood pressure rises."

Modern humans are no longer hunter-gatherers living in the wild. But the evolutionary response to a threat remains.

"A dispute with a spouse, a school examination, a scary movie, or a sudden injury — all circumstances that are frightening — set in motion the same train of physiological changes, although to a varying extent, depending on how threatened the person feels," Neuman wrote.

There are, of course, unhealthy amounts of anxiety.

More than 40 million Americans suffer from anxiety disorders, according to the Anxiety and Depression Association of America.

An anxiety disorder involves chronic anxiety that interferes with work, school, or relationships, according to the National Institute of Mental Health.

People who suffer from anxiety disorders have trouble distinguishing between things that are a threat and things that are safe, according to a study published in the March issue of Current Biology.

Other research has found that people with anxiety disorders have trouble processing unconscious emotional responses to threats and have excessive emotional responses.

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