Featured Research

from universities, journals, and other organizations

Brain Tweak Lets Sleep-deprived Flies Stay Sharp

Date:
August 1, 2008
Source:
Washington University School of Medicine
Summary:
Staying awake slows down our brains, scientists have long recognized. Mental performance is at its peak after sleep but inevitably trends downward throughout the day, and sleep deprivation only worsens these effects. For the first time, researchers have found a way to stop this downward slide in fruit flies.

Scientists testing sleep's effects on learning have devised a model that presents fruit flies with a simple choice: fly into a lighted vial or a darkened one. Flies instinctively want to fly into the lighted vial, but it contains quinine, a bitter-tasting compound they would much rather avoid. Researchers found a way to tweak the flies' brains so they could still learn to fly into the darkened vial even after they had been deprived of sleep.
Credit: Image courtesy of Washington University School of Medicine

Staying awake slows down our brains, scientists have long recognized. Mental performance is at its peak after sleep but inevitably trends downward throughout the day, and sleep deprivation only worsens these effects.

For the first time, researchers at Washington University School of Medicine in St. Louis have found a way to stop this downward slide. When scientists genetically tweaked a part of the brain involved in learning and memory in fruit flies, the flies were unimpaired even after being deprived of sleep.

"The ultimate goal is to find new ways to help people like the armed forces and first responders stay alert and on top of things when they have to be awake for extended periods of time," says Shaw. "We have drugs now that can keep people awake, but they're addictive and lose their effectiveness with repeated use. This research should help us find methods for maintaining mental acuity that have more specific effects, are less addictive and retain their potency."

Shaw's lab was the first to show that fruit flies enter a state of inactivity comparable to sleep. They demonstrated that the flies have periods of inactivity where greater stimulation is required to rouse them. These periods begin at night; like human sleep they are cyclic over the course of the night, with sleep cycles lasting 20-25 minutes. Also like humans, flies deprived of sleep one day will try to make up for the lost time by sleeping more the next day, a phenomenon referred to as increased sleep drive or sleep debt.

For the new study, first author Laurent Seugnet, Ph.D., a postdoctoral fellow, revealed that sleep deprivation impairs learning in flies. Seugnet put them through multiple runs of a maze with two options: one lighted vial with the bitter-tasting quinine in it and one darkened but quinine-free vial. Flies are instinctively drawn to light, but they want to avoid the unpleasant taste of quinine.

"This tests the flies' mental capacity in two ways: First, they've got to remember that the lighted vial is the one that has quinine in it, and then they've got to suppress their natural instinct to fly toward the light," says Seugnet.

Flies allowed normal sleep learned to avoid the lighted vial, but sleep-deprived flies did not.

A brain messenger known as dopamine is linked to some of the mental capabilities harmed by sleep loss. Researchers decided to test if this messenger could be used to block learning impairment in sleep-deprived flies. Seugnet genetically altered a line of flies so they made more copies of a dopamine receptor in brain regions known as the mushroom bodies. These areas are roughly equivalent to the human hippocampus, which is involved in learning and memory.

Sleep-deprived flies with extra dopamine receptors could still learn as if they had a full night's sleep, Seugnet found.

"Using this gene and other related genes, we may be able to find better ways to boost performance for someone like a relief worker who's had to stay awake for six straight days trying to save people trapped by an earthquake," Shaw says.

"I want to emphasize, though, that this type of treatment would just be for people who absolutely have to stay awake," he adds. "It's not about trying to cram too many hours in your day—everyone else should just suck it up and get a good night's sleep."

Shaw is currently examining the role of related genes in sleep and learning. He is also testing whether sleep deprivation in young flies impairs brain development.


Story Source:

The above story is based on materials provided by Washington University School of Medicine. Note: Materials may be edited for content and length.


Journal Reference:

  1. Seugnet L, Suzuki Y, Vine L, Gottschalk L, Shaw PJ. Receptor activation in the mushroom bodies rescues sleep loss induced learning. Current Biology, Online July 31

Cite This Page:

Washington University School of Medicine. "Brain Tweak Lets Sleep-deprived Flies Stay Sharp." ScienceDaily. ScienceDaily, 1 August 2008. <www.sciencedaily.com/releases/2008/07/080731140225.htm>.
Washington University School of Medicine. (2008, August 1). Brain Tweak Lets Sleep-deprived Flies Stay Sharp. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2008/07/080731140225.htm
Washington University School of Medicine. "Brain Tweak Lets Sleep-deprived Flies Stay Sharp." ScienceDaily. www.sciencedaily.com/releases/2008/07/080731140225.htm (accessed July 25, 2014).

Share This




More Health & Medicine News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
Too Few Teens Receiving HPV Vaccination, CDC Says

Too Few Teens Receiving HPV Vaccination, CDC Says

Newsy (July 24, 2014) The Centers for Disease Control and Prevention is blaming doctors for the low number of children being vaccinated for HPV. Video provided by Newsy
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins