But to reach the physiological root of those sensations, we need to take a close look at the vagus nerve -- actually a bundle of nerves that starts at the base of the brain and branches out through the body, linking up with the facial and vocal muscles and the heart, lungs, and gut.

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For a moment it seemed that breath was beginning to rise and fall in its chest: Aldini cut through the rib cage with a scalpel to expose the heart and applied the electrodes directly to that organ, but the body failed to resuscitate.

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Have you ever been halfway through a heart attack and thought "If only my shirt had been laced with wireless sensors that monitored respiration and body temperature, this cheese-stick-related incident might have been prevented"?

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If a person with anorexia becomes severely malnourished, every organ in the body can be damaged, including the brain, heart and kidneys.

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Nevertheless, the creation of Galileo and the improvements to GPS open up all sorts of intriguing possibilities: people prone to heart attacks, or the frail elderly, could wear small and highly accurate locator devices combined with body sensors, which could call medical help in an emergency.

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