By: By Rachael Rettner, Senior Writer

Published: 07/16/2013 04:07 PM EDT on LiveScience


Drinking plain old water may help improve mental performance, at least on certain brain tests, a small study suggests.


In the study, participants who drank about three cups of water (24 ounces, or 775 milliliters) before taking a battery of cognitive tests[1] performed better on a test that measured reaction times compared with those who did not drink water.


This finding was particular true for thirsty people. The researchers speculate that the sensation of thirst may take some attention away from the task at hand, and thus impair response time.


These results suggest that a "freeing up of attentional resources" occurs when people quench their thirst, the researchers wrote in the July 16 issue of the journal Frontiers in Human Neuroscience.


However, water consumption may not always improve cognition[2] . In a separate test of rule-learning, participants actually fared better if they did not drink water before the test. Future research should try to explain why drinking water appears to have beneficial effects on some cases, but negative effects in others, the researchers said.


"It might be that physiological processes [of drinking or not drinking water] affect performance on different tasks in different ways," said study researcher Caroline Edmonds, of the University of East London School of Psychology in England.



"Thirst might lead to better performance on some tasks," because the hormone vasopressin, which activates the thirst response, has also been linked to attention and arousal, Edmonds told LiveScience.


Earlier studies in adults have suggested that dehydration[3] can decrease mental performance, and studies in children have suggested water consumption can improve memory.


In the new study, 34 adults were asked to abstain from food or drink starting at 9 p.m., and come into a laboratory the next day for testing. Participants visited the laboratory twice: On one occasion, they were offered a cereal bar for breakfast along with water, and on another day, they were offered a cereal bar and no water.


For the reaction test, participants had to press a button as soon as they saw an object on a computer screen. Reaction times were 14 percent faster among the water group than the no water group.


Water consumption did not significantly affect performance on other tests of cognition, such as memory of words.


It's important to note that it is possible to overdose on water -- known as water intoxication -- which occurs when water dilutes sodium in the blood.


Follow Rachael Rettner @RachaelRettner [4] . Follow LiveScience @livescience [5] , Facebook [6] & Google+ [7] . Original article on LiveScience.com[8] .



Copyright 2013 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. ]]>

Also on HuffPost:




Loading Slideshow...



  • Drink First Thing


    "Place a glass of water by your bed and drink it first thing when you get up," suggests Keri Gans, M.S., R.D., a nutrition spokesperson and author of "The Small Changes Diet," in an email to The Huffington Post. Try drinking it <a href="http://www.health.com/health/library/topic/0,,abk5466_abk5467,00.html" target="_hplink">before your usual coffee or tea</a>.
    <br><br>
    <em>Flickr photo by <a href="http://www.flickr.com/photos/jkonig/2168435597/" target="_hplink">JKönig</a></em>




  • Sip At Your Desk


    Keep a reusable cup or bottle at your desk. When it's empty, go refill it. It's a great way to fit in <a href="http://www.huffingtonpost.com/2012/01/13/sitting_n_1202800.html" target="_hplink">more steps during the day</a>, too!
    <br><br>
    Neglecting the bottle? "Put a sticky note on your computer to remind you to drink up," says Gans. If that <em>still</em> doesn't work, try setting a reminder alarm on your phone or calendar.
    <br><br>
    <em>Flickr photo by <a href="http://www.flickr.com/photos/jcestnik/3889059326/" target="_hplink">jennypdx</a></em>




  • Bring Water To Go


    If you don't have a desk job, or even if you do, toss a water bottle in your bag to sip while you're out and about, says Gans.
    <br><br>
    <em>Flickr photo by <a href="http://www.flickr.com/photos/yourdon/4105822390/" target="_hplink">Ed Yourdon</a></em>




  • Drink Before You Eat


    When you sit down to a meal, have a glass or two of water before you start to eat. Not only can it serve as a reminder to drink more, but a 2010 study found that drinking <a href="http://www.sciencedaily.com/releases/2010/08/100823142929.htm" target="_hplink">two glasses before meals</a> helped people lose five pounds more over 12 weeks than people who did not increase their water intake.
    <br><br>
    <em>Flickr photo by <a href="http://www.flickr.com/photos/earlg/237204111/" target="_hplink">Earl</a></em>




  • Dilute Your Juice


    If you're the type of person who'd rather reach for a sweet sip than plain ol' water, you don't have to cut out juice cold turkey. Instead, Gans recommends filling 1/4 of your glass with 100 percent fruit juice, then topping it off with water or seltzer.
    <br><br>
    <em>Flickr photo by <a href="http://www.flickr.com/photos/73981677@N00/5401688691/" target="_hplink">badoir</a></em>




  • Skip The Soda


    If you find yourself reaching for a soda or other sweet drink that isn't 100 percent fruit juice, use that craving as a reminder instead to grab a glass of H2O. And if you can't quit those bubbles? "Seltzer counts as water," says Gans.
    <br><br>
    <em>Flickr photo by <a href="http://www.flickr.com/photos/spencereholtaway/1412762050/" target="_hplink">Spencer E Holtaway</a></em>




  • Give Your Water Some Flavor


    Still can't get over the bland taste? "Use fresh fruit or veggies to flavor your water," says Gans. Cucumber, lemon, lime and watermelon are tasty options, she says, and high in water themselves.
    <br><br>
    <em>Flickr photo by <a href="http://www.flickr.com/photos/riekhavoc/4665442112/" target="_hplink">Kaytee Riek</a></em>




  • Track Your Intake


    Just as <a href="http://www.sciencedaily.com/releases/2008/07/080708080738.htm" target="_hplink">keeping a food diary</a> can help you key into what and when you're eating, tracking your water intake can similarly shine a light on where you could fit in more fluids. There's even <a href="http://itunes.apple.com/us/app/waterlogged-drink-more-water/id352199775?mt=8" target="_hplink">an app for that</a>!
    <br><br>
    <em>Flickr photo by <a href="http://www.flickr.com/photos/ari/765880039/" target="_hplink">Steve Rhodes</a></em>




  • Related Video