Biologically, physiologically, functionally - there's no difference between real altitude and these artificial hypoxic environments.

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And they have come about without upgrading the human brain genetically or physiologically.

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The gender issue exists in the brain, though experts do not agree on whether it's psychologically or physiologically based.

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Because the area of the brain affected also is where mood regulation occurs, he said, Ms. Giffords could face physiologically-caused depression.

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According to Daniel Goleman, author of Emotional Intelligence and Primal Leadership, our emotions are physiologically part of our limbic system.

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Neuroplasticity has replaced the formerly-held position that the brain is a physiologically static organ, and explores how the brain changes throughout life.

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This works because the red pigment is physiologically costly to produce.

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Mice and humans are physiologically alike, so a similar effect might be expected for people, but the fact that mice are nocturnal and humans diurnal is a serious complicating factor.

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The most likely answer, as he explains in a paper in the Journal of Experimental Biology, is that urine, though cheap to produce when water is plentiful, is a physiologically costly product when water is scarce.

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