Blood flow increases to your muscles, your attention sharpens, and your pupils dilate. Adrenaline is chemically related to the pleasure hormone dopamine, and dangerous situations can also cause your body to produce endorphins, which suppress pain and heighten pleasure.
These systems may have evolved because a certain amount of risk-taking has survival value – we are descended from people brave enough to hunt mammoths, after all. There are specific genes that increase the ‘adrenaline high’ for some people, and a 2002 study for the World Health Organization found these genes in both adrenaline junkies and drug addicts.
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Asked by: Sarah Weitzman,Penzance
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