For kids who have good grades but test-anxiety, that can be a real blessing.

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In one test of anxiety, animals were given the choice of staying in the relative safety of a dark box, or of venturing into a lighted box.

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Similarly, in another test of anxiety, animals were given the choice of venturing out on an elevated and unprotected bar to explore their environment, or remain in the relative safety of a similar bar protected by enclosing walls.

FORBES: Thinking With Your Gut. Literally.

After all, the major market indexes pulled back to (successfully) test technical support, creating a lot of anxiety among investors in the process, and the ensuing rally has been so sharp, and so sudden, that you have to believe many have been left behind.

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But anxiety and claustrophobia prevented Emily from getting the test.

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If you have a speech to give, a test to take or an important meeting, for example, some anxiety will help you focus on the event and make sure you're prepared for it, Barlow said.

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The best way to stay in the "sweet spot, " Dr. Moser says, is to channel the anxiety into productive activity like studying and acing the test.

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The current test, called PSA, is less than ideal and can cause men undue anxiety by showing up tumours in the prostate gland that might never go on to cause any health problem.

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