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U.S. Army develops algorithm for getting ‘optimal alertness’ from caffeine
Caffeine is consumed by some 90% of Americans every day, but not everyone is getting the most of its stimulating effects.

Everyone knows a morning cup of coffee helps you stay focused throughout the day, even after a bad night’s sleep.
But what’s not obvious is when and how much you should consume to achieve the best effects. That’s the focus of a new study funded by the U.S. Army and published in the Journal of Sleep Research.
Caffeine is the most widely used stimulant in the world, consumed in some form by some 90 percent of Americans each day. Studies have shown it reliably boosts performance among sleep-deprived people on cognitive tasks, even after long periods of restricted sleep. The downside is that caffeine, especially high amounts consumed over several days, can prevent sleep-deprived people from making up lost sleep, a measure known as ‘sleep debt’.

The researchers behind the new study aimed to find the optimal balance between the amount of caffeine and the time it’s administered. To do so, they used data from four past caffeine-sleep studies and inputted them into an algorithm built on the unified model of performance, which is a mathematical model that accurately predicts the effects of sleep–wake schedules and caffeine consumption on simple neurobehavioral tasks.
The team, led by the U.S. Army Medical Research and Materiel Command’s Dr. Jaques Reifman, ran thousands of simulations across a wide range of doses and sleep-wake schedules.
“We found that by using our algorithm, which determines when and how much caffeine a subject should consume, we can improve alertness by up to 64 percent, while consuming the same total amount of caffeine,” Reifman told Science Daily. “Alternatively, a subject can reduce caffeine consumption by up to 65 percent and still achieve equivalent improvements in alertness.”
The algorithm could someday be used, for instance, by college students who want to know when they should consume caffeine “so you are as alert as possible during the exam,” Reifman told Live Science.
The optimal caffeine dose amounts and times depended on each individual scenario, so there’s no universal recommendation for when and much caffeine to consume. However, the U.S. Army is reportedly using the algorithm in experiments with soldiers in an effort to improve sleep health in the military, an organization in which sleep deprivation is a constant and often unavoidable problem.
The base algorithm looks like this:
If that's not your cup of joe, a simplified version of the algorithm is available to the public through the 2B-Alert app, which lets users enter their sleep schedules and caffeine intake to find out when and how much caffeine they should consume.

2 new ways to find aliens, according to a Nobel Prize winner
Physicist Frank Wilczek proposes new methods of searching for extraterrestrial life.
Alien spaceships.
- Nobel Prize-winning physicist Frank Wilczek thinks we are not searching for aliens correctly.
- Instead of sending out and listening for signals, he proposes two new methods of looking for extraterrestrials.
- Spotting anomalies in planet temperature and atmosphere could yield clues of alien life, says the physicist.
1. Atmosphere chemistry
<p>Like we found out with our own effect on the Earth's atmosphere, making a <a href="https://ozonewatch.gsfc.nasa.gov/facts/hole_SH.html" target="_blank">hole in the ozone layer</a>, the gases around a planet can be impacted by its inhabitants. "Atmospheres are especially significant in the search for alien life," <a href="https://www.wsj.com/articles/looking-for-signs-of-alien-technology-11581605907" target="_blank">writes Wilczek</a> "because they might be affected by biological processes, the way that photosynthesis on Earth produces nearly all of our planet's atmospheric oxygen."</p><p>But while astrobiology can provide invaluable clues, so can looking for the signs of alien technology, which can also be manifested in the atmosphere. An advanced alien civilization might be colonizing other planets, turning their atmospheres to resemble the home planets. This makes sense considering our own plans to terraform other planets like Mars to allow us to breathe there. Elon Musk even <a href="https://www.space.com/elon-musk-serious-nuke-mars-terraforming.html" target="_blank">wants to nuke the red planet.</a></p>The Most Beautiful Equation: How Wilczek Got His Nobel
<div class="rm-shortcode" data-media_id="ijBZzuI2" data-player_id="FvQKszTI" data-rm-shortcode-id="061a3de613c45f42b05432a2949e7caa"> <div id="botr_ijBZzuI2_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/ijBZzuI2-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/ijBZzuI2-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/ijBZzuI2-FvQKszTI.js"></script> </div>2. Planet temperatures
<p>Wilczek also floats another idea - what if an alien civilization created a greenhouse effect to raise the temperature of a planet? For example, if extraterrestrials were currently researching Earth, they would likely notice the increased levels of carbon dioxide that are <a href="https://www.epa.gov/ghgemissions/overview-greenhouse-gases" target="_blank">heating up</a> our atmosphere. Similarly, we can looks for such signs around the exoplanets.</p><p>An advanced civilization might also be heating up planets to raise their temperatures to uncover resources and make them more habitable. Unfreezing water might be one great reason to turn up the thermostat. </p><p>Unusually high temperatures can also be caused by alien manufacturing and the use of artificial energy sources like nuclear fission or fusion, suggests the scientist. Structures like the hypothetical <a href="https://bigthink.com/paul-ratner/this-mind-bending-scale-predicts-the-power-of-advanced-civilizations" target="_self">Dyson spheres</a>, which could be used to harvest energy from stars, can be particularly noticeable. </p>Wilczek: Why 'Change without Change' Is One of the Fundamental Principles of the ...
<div class="rm-shortcode" data-media_id="KrUgLGWm" data-player_id="FvQKszTI" data-rm-shortcode-id="cc13c3c65924439c1992935c61ab8977"> <div id="botr_KrUgLGWm_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/KrUgLGWm-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/KrUgLGWm-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/KrUgLGWm-FvQKszTI.js"></script> </div>As we approach death, our dreams offer comfort and reconciliation
As patients approached death, many had dreams and visions of deceased loved ones.
One of the most devastating elements of the coronavirus pandemic has been the inability to personally care for loved ones who have fallen ill.
Surprising new feature of human evolution discovered
Research reveals a new evolutionary feature that separates humans from other primates.
Human evolution.
- Researchers find a new feature of human evolution.
- Humans have evolved to use less water per day than other primates.
- The nose is one of the factors that allows humans to be water efficient.
A model of water turnover for humans and chimpanzees who have similar fat free mass and body water pools.
Credit: Current Biology
Skepticism: Why critical thinking makes you smarter
Being skeptical isn't just about being contrarian. It's about asking the right questions of ourselves and others to gain understanding.
