Several recent brain-scan studies have shown that yawning evokes a unique neural activity in the areas of the brain that are directly involved in generating social awareness and creating feelings of empathy. One of those areas is the precuneus, a tiny structure hidden within the folds of the parietal lobe. According to researchers at the Institute of Neurology in London, the precuneus appears to play a central role in consciousness, self-reflection, and memory retrieval. The precuneus is also stimulated by yogic breathing, which helps explain why different forms of meditation contribute to an increased sense of self-awareness. It is also one of the areas hardest hit by age-related diseases and attention deficit problems, so it's possible that deliberate yawning may actually strengthen this important part of the brain.
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But yawning doesn't just relax you—it quickly brings you into a heightened state of cognitive awareness. Students yawn in class, not because the teacher is boring (although that will make you yawn as well, as you try to stay focused on the monotonous speech), but because it rids the brain of sleepiness, thus helping you stay focused on important concepts and ideas. It regulates consciousness and our sense of self, and helps us become more introspective and self-aware. Of course, if you happen to find yourself trapped in a room with a dull, boring, monotonous teacher, yawning will help keep you awake.
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Yawning, as a mechanism for alertness, begins within the first 20 weeks after conception. It helps regulate the circadian rhythms of newborns, and this adds to the evidence that yawning is involved in the regulation of wakefulness and sleep. Since circadian rhythms become asynchronous when a person's normal sleep cycle is disturbed, yawning should help the late-night partygoer reset the brain's internal clock. Yawning may also ward off the effects of jet lag and ease the discomfort caused by high altitudes.

So what is the underlying mechanism that makes yawning such an essential tool? Besides activating the precuneus, it regulates the temperature and metabolism of your brain. It takes a lot of neural energy to stay consciously alert, and as you work your way up the evolutionary ladder, brains become less energy efficient. Yawning probably evolved as a way to cool down the overly active mammalian brain, especially in the areas of the frontal lobe. Some have even argued that it is a primitive form of empathy. Most vertebrates yawn, but it is only contagious among humans, great apes, macaque monkeys, and chimpanzees. In fact, it's so contagious for humans that even reading about it will cause a person to yawn.

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My advice is simple. Yawn as many times a day as possible: when you wake up, when you're confronting a difficult problem at work, when you prepare to go to sleep, and whenever you feel anger, anxiety, or stress. Yawn before giving an important talk, yawn before you take a test, and yawn while you meditate or pray because it will intensify your spiritual experience.

Ill b honest, i didnt read it all.... i saw the small print and was lik oh-no,