Nature walks boost brain power and mood

A new study provides more proof being outdoors is good for you not only physically -- but mentally as well.

Researchers at Stanford University asked two groups of people to take a 90-minute walk -- one through a natural area one along a busy street.

Afterward, their brains were scanned.

Those that took the nature walk showed decreased activity in the subgenual prefontal cortex -- an area of the brain associated with negative self-reflection.

Researchers say this shows that going out in nature -- even for a short time -- can lessen the line of thinking often associated with depression and mental illness.

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