A common point is that longtime editors have run their course, added everything they know. It’s worth pointing out that Wikipedia’s exponential growth could not continue forever. Most likely is that Wikipedia is finding its natural stable base of editors

German researchers subjected test participants to pink noise (an example above) tuned to their brain waves, right before entering deep sleep (if you need additional explanation about the difference between white vs. pink noise like I did, check out this slightly technical description). Those exposed to the tuned sounds exhibited longer periods of slow wave deep sleep. Not only were participants better off in the deep sleep department, but they were able to retain memory of words they were exposed to before entering sleep.

No time for a nap? The ideal remedy for the mental fatigue that occurs after sleep loss is an afternoon nap, says Matthew Edlund, MD, author of The Power of Rest. But since that’s not possible for most people with jobs, the next best thing is a form of active rest called “paradoxical relaxation.” Dr. Edlund explains: Focus on one muscle group in your body for at least 15 seconds, concentrating only on how it feels and nothing else. Repeat up and down the body. Surprise—you feel recharged.

The researchers followed subjects for an average of six years, measuring their diets, physical activity and how much they napped. They found that occasional napping was associated with a 12 percent reduction in the risk of coronary heart disease, but that regular napping — at least three days weekly — was associated with a 37 percent reduction.

Pathan women in the North-West Frontier Province (1901–1955) of Pakistan during the Anglo-Afghan Wars used a method of execution involving urine, Pathan women urinated into prisoner’s mouths. Captured British soldiers were spread out on the ground and fastened with restraints to the ground, then a stick or a piece of wood was used to keep their mouth open to prevent swallowing. Pathan women, taking turns one at a time, then squatted and urinated directly into the mouth of the man until he drowned in the urine.

ABM has developed a mask called the Somneo Sleep Trainer that exploits one- or two-hour windows for strategic naps in mobile sleeping environments. Screening out ambient noise and visual distractions, the mask carries a heating element around the eyes, based on the finding that facial warming helps send people to sleep. It also carries a blue light that gradually brightens as your set alarm time approaches, suppressing the sleep hormone melatonin for a less groggy awakening. Sleep ideally contains multiple 60- to 90-minute cycles, from slow-wave sleep back up to REM, but a 20-minute nap is all about dipping into Stage 2 as quickly as possible. The idea of the Somneo is to fast-track through Stage 1 sleep, a gateway stage with few inherent benefits, and enter Stage 2, which at least restores fatigued muscles and replenishes alertness.