Archive for the ‘Female Athlete’ Category

Research news from Journal of Mass Spectrometry

A new mass spectrometry test can help sports anti-drug doping officials to detect whether an athlete has used drugs that boost naturally occurring steroid levels. The test is more sensitive compared to previous alternatives, more capable of revealing specific suspicious chemical in the body, faster to perform, and could be run on standard drug-screening laboratory equipment. The new test is announced in a special issue of the Journal of Mass Spectrometry that concentrates on detecting drugs in sports.

One of the roles of the masculinising hormone testosterone is to increase muscle size and strength. Taking extra testosterone, or taking a chemical that the body can use to create extra testosterone, could therefore enhance an athlete’s performance. For this reason taking it is banned by the World Anti-Doping Agency (WADA).

The exact level of testosterone varies considerably between different people, so simply measuring total testosterone in an athlete’s urine can not show whether he or she has deliberately taken extra. There is, however, a second chemical in the body, epitestosterone, which is normally present in approximately equal proportions to testosterone. Comparing the ratio of testosterone to epitestosterone can then indicate whether testosterone or a precursor has been taken.

The problem is that it is not always easy to measure these two substances, particularly as they are only present in urine at very low concentrations.

A team of scientists the Sports Medicine Research and Testing Laboratory at the University of Utah have developed a test that makes use of liquid chromatography-tandem mass spectrometry. This method has incredibly high sensitivity (down to 1 ng/ml) and increases the power with which officials can search for both testosterone and epitestosterone within a sample.

“Our system means that we can determine the testosterone/epitestosterone ratio in a sample with greater confidence, and therefore be in a better position to spot doping violations without falsely accusing innocent athletes,” says lead investigator Dr Jonathan Danaceau.

“Not only is the test more sensitive, it is also faster to perform,” says colleague Scott Morrison.

“Having this sort of test available makes cheating harder and lets us take one more step towards enabling free and fair competition,” says Laboratory Director Dr Matthew Slawson.

This paper is part of a special issue for the Olympic Games from the Journal of Mass Spectrometry which focuses of drug use in sport. The issue is available free of charge online for one month at http://www.interscience.wiley.com/journal/jms. The other articles publishing in this issue are:

 

  • History of Mass Spectrometry at Olympic Games (DOI: 10.1002/jms.1445)
  • Nutritional supplements cross-contaminated and faked with doping substances (DOI: 10.1002/jms.1452)
  • Hair analysis of anabolic steroids in connection with doping control results from horse samples (DOI: 10.1002/jms.1446)
  • Mass spectrometric determination of Gonadotrophin releasing hormone (GnRH) in human urine for doping control purposes by means of LC-ESI-MS/MS (DOI: 10.1002/jms.1438)
  • Liquid chromatographic-mass spectrometric analysis of glucuronide-conjugated anabolic steroid metabolites: method validation and inter-laboratory comparison (DOI: 10.1002/jms.1434)
  • Mass Spectrometry of Selective Androgen Receptor Modulators (DOI: 10.1002/jms.1438)
  • Can glycans unveil the origin of glycoprotein hormones? – human chorionic gonadotropin as an example (DOI: 10.1002/jms.1448)
  • A High-Throughput Multicomponent Screening Method for Diuretics, Masking Agents, Central Nervous System Stimulants and Opiates in Human Urine by UPLC-MS/MS (DOI: 10.1002/jms.1436)
  • The application of carbon isotope ratio mass spectrometry to doping control (DOI: 10.1002/jms.1437)
  • Identification of zinc-alpha-2-glycoprotein binding to clone ae7a5 anti-human epo antibody by means of nano-hplc and high-resolution highmass accuracy esi-ms/ms (DOI: 10.1002/jms.1444)
  • Low LC-MS/MS Detection of Glycopeptides Released from pmol Levels of Recombinant Erythropoietin using Nanoflow HPLC-Chip Electrospray Ionization (DOI: 10.1002/jms.1439)
  • Introduction of HPLC/Orbitrap mass spectrometry as screening method for doping control (DOI: 10.1002/jms.1447)

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Article adapted by MD Sports from original press release.
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Contact: Jennifer Beal
Wiley-Blackwell

University Park, Pa. — Girls and boys are now equally caught up in the social pressure for a muscular body image currently lauded in popular culture. A Penn State researcher contends those pressures are leading girls and boys down unhealthy avenues such as the misuse of anabolic steroids.

“Young girls have always had to struggle against the media stereotypes of stick-thin models or voluptuous sexuality, but with the rising popularity of women sports, girls are bombarded with buffed body images,” says Dr. Charles Yesalis, professor of health policy and administration, and exercise and sports science at Penn State, and editor of the newest edition of the book “Anabolic Steroids in Sports and Exercise.” “Now, young boys face pop culture musclemen like The Rock and Steve Austin, given the influence of professional wrestling shows.”

“The current film ‘Charlie’s Angels’ sports karate-kicking women in cool clothes,” he added. “Today’s children look with envy at the physiques of actors Arnold Schwarzenegger, Jean-Claude Van Damme, Wesley Snipes, and Linda Hamilton, whose roles call for a muscular build. Hollywood stars are openly taking Human Growth Hormone (HGH) injections to combat aging.”

In addition, children are entering competitive sports at younger ages and many working families have children signed up in two or three sports. Parents, coaches and young athletes are facing growing violence in amateur athletics. The pressure to win at all costs continues to weigh heavily on children, Yesalis notes.

The concern is that many youths will take shortcuts to achieving a muscular build by using anabolic steroids. Female athletes also are pressured to achieve low body fat to excel in their sport. The Penn State researcher has seen evidence that the pressures are reaching down to young children. For example, the book cites figures from the Monitoring The Future Study, a national-level epidemiological survey conducted annually since 1975. Approximately 50,000 8th, 10th and 12 graders are surveyed each year.

The MTF data shows that during the 1990s, anabolic steroid use among 12 graders –both boys and girls – rose to an all-time high with more than 500,000 adolescents having cycled – an episode of use of 6 to 12 weeks – during their lifetime. And the percentage of girls alone doubled in the same period.

A 1998 study of 965 youngsters at four Massachusetts middle schools found that 2.7 percent admitted to taking illegal steroids for better sports performance. That included some boys and girls as young as 10 years old. “This year’s Olympic doping scandals and the epidemic of anabolic steroids in professional baseball just glorify and justify steroids to impressionable youths,” Yesalis notes. “The use of anabolic steroids has cascaded down from the Olympic, professional and college levels to high schools and junior high schools and now middle schools for athletes and non-athletes alike. ”

“Anabolic steroids are made to order for a female wanting to attain a lean athletic body. While most drug abuse has outcomes that tend to discourage use, females who use anabolic steroids may experience a decrease in body fat, increased muscle size and strength, and enhanced sports performance,” he says.

Girls and boys misusing anabolic steroids may win approval and rewards from parents, coaches and peers, but don’t realize there are long-term negative effects on their health, particularly girls, according to Yesalis. Young girls face potential permanent side effects of male hair growth or baldness, deepening of the voice, the enlargement of the clitoris as well as the known risks of heart and liver diseases.

Published by Human Kinetics, the book incorporates the latest research, experience and insights of 15 experts on the scientific, clinical, historical, legal and other aspects of steroid abuse and drug testing. New information looks at the effects of steroids on health, particularly that of women.

This year, trials of East German doctors, coaches and officials reveal records of systematic doping of young athletes without their own or parents’ knowledge. In 1974, officials’ plan to turn the tiny Communist nation into a superpower in sports included giving performance-enhancing drugs to all competing athletes including children as young as 10 years old. The indictments included 142 former East German athletes who now complain of health problems. In media reports, several female athletes report incidents of miscarriages, liver tumor, gynecological problems and enlarged heart, all showing up decades after the steroid misuse.

“Our society’s current strategy for dealing with the abuse of anabolic steroids in sport primarily involves testing, law enforcement and education,” Yesalis says. “But our efforts to deal with this problem have not been very successful. Unless we deal with the social environment that rewards winning at all costs and an unrealistic physical appearance, we won’t even begin to address the problem.”

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Article adapted by MD Sports Weblog from original press release.
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Contact: Vicki Fong
Penn State

Genetic research into athletic ability should be encouraged for its potential benefits in both sport and public health, a leading group of scientists meeting at the University of Bath said today.

Genetic research into athletic ability should be encouraged for its potential benefits in both sport and public health, a leading group of scientists meeting at the University of Bath said today.

However, ethical concerns, such as whether seeking information about differences between ethnic groups could be perceived as racist research, need to be properly addressed, they warn.

Their recommendations are published in a ‘position stand’ on genetic research and testing launched at the British Association of Sport & Exercise Sciences annual meeting today.

They call for more genetic research in the sport and exercise sciences because of the anticipated benefits for public health, but want researchers to take a more active role in debating the implications of their work with the public.

“If a powerful muscle growth gene was identified, on the one hand this could help develop training programmes that increase muscle size and strength in athletes, but even more importantly the knowledge could be used to develop exercise programmes or drugs to combat muscle wasting in old age,” said Dr Alun Williams from Manchester Metropolitan University, one of the report’s authors.

“We, as scientists investigating genetics, acknowledge a public concern about some genetic research and we believe scientists need to engage in public in debates about the potential benefits of their research.

“Research into the athletic success of East African distance runners or sprinters of West African ancestry might be perceived as unethical.

“But understanding the limits of human exercise capacity in sport could lead to the development of treatments for a range of diseases like cancer and cardiovascular disease.”

The potential applications of genetic testing in sport and exercise also raise some ethical concerns, for example in identifying potential athletic ability before birth.

An Australian company already offers the first genetic performance test (for the ACTN3 gene) which has been linked to sprint and power performance.

The report authors are sceptical about whether this test is useful but anticipate that more advanced versions of these tests will be available in future.

“We are not yet at a point where we can identify a potential future Olympic champion from genetic tests but we may not be very far away,” said Dr Williams, who wrote the report with Drs Henning Wackerhage (Aberdeen University), Andy Miah (University of Paisley), Roger Harris (University of Chichester) and Hugh Montgomery (University College London).

They highlight two dangers of genetic performance tests. Firstly, genetic performance tests might later be linked to disease. For example, a muscle growth gene may later be linked to cancer growth.

“Not all people may want to know, while young that they are at increased risk of cancer by early middle age, but they might inadvertently become aware of that just because they had a ‘sport gene’ test,” said Dr Williams.

Secondly, genetic performance tests can be performed even before birth and this may lead to the selection of foetuses or to abortions based on athletic potential.

The report recommends genetic counselling and that the testing should be confined to mature individuals who fully understand the relevant issues.

Genetic tests might also be used to screen for health risks during sport such as genes that are linked to sudden cardiac death.

Genetic tests for sudden cardiac death are already available but the report recommends that such testing should not be enforced on athletes.

Problems with mandatory testing are highlighted by the case of the basketball player Eddy Curry, who had an irregular heart beat.

Curry was asked by his club, the Chicago Bulls, to perform a predictive genetic test for a heart condition. The athlete refused and was traded to the New York Knicks who did not make such a demand.

In future, genetic tests might be used to identify those that respond with the biggest drop in cholesterol, blood pressure or glucose to exercise.

In a personalised medicine approach, such tests could be used to select subjects for therapeutic exercise programmes but scientists are concerned that this might undermine the ‘exercise for all’ message that already seems difficult to get across to the public.

The authors say that genetic testing might also be used to detect gene doping, which may be a real threat by the time of the London Olympics in 2012, or to show that positive doping tests are the result of a genetic mutation in an athlete.

The report recommends that genetic testing should be used for anti-doping testing as long as the genetic samples are destroyed after testing.

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Article adapted by MD Sports from original press release.
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Contact: Andrew McLaughlin
University of Bath

Experts at The University of Nottingham are to investigate the effect of nutrients on muscle maintenance in the hope of determining better ways of keeping up our strength as we get old.

The researchers, based at the School of Graduate Entry Medicine and Health in Derby, want to know what sort of exercise we can take and what food we should eat to slow down the natural loss of skeletal muscle with ageing.

The team from the Department of Clinical Physiology, which has over 20 years experience in carrying out this type of metabolic study, need to recruit 16 healthy male volunteers in two specific age groups to help in it’s research.

Skeletal muscles make up about half of our body weight and are responsible for controlling movement and maintaining posture. However, at around 50 years of age our muscles begin to waste at approximately 0.5 per cent to one per cent a year. It means that an 80 year old may only have 70 per cent of the muscle of a 50 year old.

Since the strength of skeletal muscle is proportional to muscle size, such wasting makes it harder to carry out daily activities requiring strength, such as climbing stairs and leads to a loss of independence and an increased risk of falls and fractures.

In order for skeletal muscles to maintain their size, the large reservoirs of muscle protein require constant replenishment in the way of amino acids from protein contained within the food we eat. In fact, amino acids from our food act not only as the building blocks of muscle proteins but also actually ‘tell’ our muscle cells to build proteins.

Recent research from the clinical physiology team has shown that the cause of muscle wasting with ageing appears to be an attenuation of muscle building in response to protein feeding. In other words, as we age we lose the ability to covert the protein in the food we eat in to muscle tissue. The proposed research will investigate the mechanisms responsible for this deficit.

Dr Philip Atherton, who is currently recruiting volunteers, said: “I am really excited to be involved in this project because if we can determine ways to better maintain muscle mass as we age it will greatly benefit us all.”

The researchers are looking for 16 healthy, non-smoking, male volunteers aged 18 to 25 and 65 to 75.

Initially, the volunteers will undergo a health screening and then on a different day, under the supervision of a doctor, will be infused with an amino acid mixture to simulate feeding along with a ‘tagged’ amino acid that allows them to assess muscle building. To make these measures, blood samples will be taken from the arm and muscle biopsies from the thigh muscle under local anaesthesia. Volunteers will receive an honorarium to cover their expenses.

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Article adapted by MD Sports from original press release.
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Contact: Lindsay Brooke
University of Nottingham

 

The study will take place at The University of Nottingham’s Medical School which based at the City Hospital in Derby.

Recipe to recover more quickly from exercise: Finish workout, eat pasta, and wash down with five or six cups of strong coffee.

Glycogen, the muscle’s primary fuel source during exercise, is replenished more rapidly when athletes ingest both carbohydrate and caffeine following exhaustive exercise, new research from the online edition of the Journal of Applied Physiology shows. Athletes who ingested caffeine with carbohydrate had 66% more glycogen in their muscles four hours after finishing intense, glycogen-depleting exercise, compared to when they consumed carbohydrate alone, according to the study, published by The American Physiological Society.

The study, “High rates of muscle glycogen resynthesis after exhaustive exercise when carbohydrate is co-ingested with caffeine,” is by David J. Pedersen, Sarah J. Lessard, Vernon G. Coffey, Emmanuel G. Churchley, Andrew M. Wootton, They Ng, Matthew J. Watt and John A. Hawley. Dr. Pedersen is with the Garvan Institute of Medical Research in Sydney, Australia, Dr. Watt is from St. Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia. All others are with the Royal Melbourne Institute of Technology University (RMIT) in Bundoora, Victoria, Australia.

A fuller audio interview with Dr. Hawley is available in Episode 11 of the APS podcast, Life Lines, at www.lifelines.tv. The show also includes an interview with Dr. Stanley Schultz, whose physiological discovery of how sugar is transported in the gut led to the development of oral rehydration therapy and sports drinks such as Gatorade and Hi-5.

Caffeine aids carbohydrate uptake  

It is already established that consuming carbohydrate and caffeine prior to and during exercise improves a variety of athletic performances. This is the first study to show that caffeine combined with carbohydrates following exercise can help refuel the muscle faster.

“If you have 66% more fuel for the next day’s training or competition, there is absolutely no question you will go farther or faster,” said Dr. Hawley, the study’s senior author. Caffeine is present in common foods and beverages, including coffee, tea, chocolate and cola drinks.

The study was conducted on seven well-trained endurance cyclists who participated in four sessions. The participants first rode a cycle ergometer until exhaustion, and then consumed a low-carbohydrate dinner before going home. This exercise bout was designed to reduce the athletes’ muscle glycogen stores prior to the experimental trial the next day.

The athletes did not eat again until they returned to the lab the next day for the second session when they again cycled until exhaustion. They then ingested a drink that contained carbohydrate alone or carbohydrate plus caffeine and rested in the laboratory for four hours. During this post-exercise rest time, the researchers took several muscle biopsies and multiple blood samples to measure the amount of glycogen being replenished in the muscle, along with the concentrations of glucose-regulating metabolites and hormones in the blood, including glucose and insulin.

The entire two-session process was repeated 7-10 days later. The only difference was that this time, the athletes drank the beverage that they had not consumed in the previous trial. (That is, if they drank the carbohydrate alone in the first trial, they drank the carbohydrate plus caffeine in the second trial, and vice versa.)

The drinks looked, smelled and tasted the same and both contained the same amount of carbohydrate. Neither the researchers nor the cyclists knew which regimen they were receiving, making it a double-blind, placebo-controlled experiment.

Glucose and insulin levels higher with caffeine ingestion
The researchers found the following:  
  • one hour after exercise, muscle glycogen levels had replenished to the same extent whether or not the athlete had the drink containing carbohydrate and caffeine or carbohydrate only
  • four hours after exercise, the drink containing caffeine resulted in 66% higher glycogen levels compared to the carbohydrate-only drink
  • throughout the four-hour recovery period, the caffeinated drink resulted in higher levels of blood glucose and plasma insulin
  • several signaling proteins believed to play a role in glucose transport into the muscle were elevated to a greater extent after the athletes ingested the carbohydrate-plus-caffeine drink, compared to the carbohydrate-only drink

 Dr. Hawley said it is not yet clear how caffeine aids in facilitating glucose uptake from the blood into the muscles. However, the higher circulating blood glucose and plasma insulin levels were likely to be a factor. In addition, caffeine may increase the activity of several signaling enzymes, including the calcium-dependent protein kinase and protein kinase B (also called Akt), which have roles in muscle glucose uptake during and after exercise.

Lower dose is next step  

In this study, the researchers used a high dose of caffeine to establish that it could help the muscles convert ingested carbohydrates to glycogen more rapidly. However, because caffeine can have potentially negative effects, such as disturbing sleep or causing jitteriness, the next step is to determine whether smaller doses could accomplish the same goal.

Hawley pointed out that the responses to caffeine ingestion vary widely between individuals. Indeed, while several of the athletes in the study said they had a difficult time sleeping the night after the trial in which they ingested caffeine (8 mg per kilogram of body weight, the equivalent of drinking 5-6 cups of strong coffee), several others fell asleep during the recovery period and reported no adverse effects.

Athletes who want to incorporate caffeine into their workouts should experiment during training sessions well in advance of an important competition to find out what works for them.

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Article adapted by MD Sports from original press release.
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Contact: Christine Guilfoy
American Physiological Society

Physiology is the study of how molecules, cells, tissues and organs function to create health or disease. The American Physiological Society (APS) has been an integral part of this scientific discovery process since it was established in 1887.

A University of Colorado at Boulder study of a space-age, low-gravity training machine used by several 2008 Olympic runners showed it reduced impacts on muscles and joints by nearly half when subjects ran at the equivalent of 50 percent of their body weight.

The new study has implications for both competitive runners rehabilitating from injuries and for ordinary people returning from knee and hip surgeries, according to Associate Professor Rodger Kram of CU-Boulder’s integrative physiology department.

Known as the “G-Trainer,” the machine consists of a treadmill surrounded by an inflatable plastic chamber that encases the lower body of the runner, said Kram. Air pumped into the chamber increases the pressure and effectively reduces the weight of runners, who are sealed in the machine at the waist in a donut-shaped device with a special zipper and “literally lifted up by their padded neoprene shorts,” he said.

Published in the August issue of the Journal of Applied Biomechanics, the study is the first to quantify the effects of running in the G-Trainer, built by Alter-G Inc. of Menlo Park, Calif., using technology developed at NASA’s Ames Research Center in California. The paper was authored by Kram and former CU-Boulder doctoral student Alena Grabowski, now a postdoctoral researcher at the Massachusetts Institute of Technology.

Although G-Trainers have been used in some sports clinics and college and professional sports training rooms since 2006, the new study is the first scientific analysis of the device as a training tool for running, said Grabowski.

“The idea was to measure which levels of weight support and speeds give us the best combination of aerobic workout while reducing the impact on joints,” said Kram. “We showed that a person can run faster in the G-Trainer at a lower weight and still get substantial aerobic benefits while maintaining good neuromuscular coordination.”

The results indicated a subject running at the equivalent of half their weight in the G-Trainer at about 10 feet per second, for example — the equivalent of a seven-minute mile — decreased the “peak” force resulting from heel impact by 44 percent, said Grabowski. That is important, she said, because each foot impact at high speed can jar the body with a force equal to twice a runner’s weight.

Several former CU track athletes participating in the 2008 Olympics in Beijing have used the machine, said Kram. Alumna Kara Goucher, who will be running the 5,000- and 10,000-meter races in Beijing, has used the one in Kram’s CU-Boulder lab and one in Eugene, Ore., for rehabilitation, and former CU All-American and Olympic marathoner Dathan Ritzenhein also uses a G-Trainer in his home in Oregon. Other current CU track athletes who have been injured have tried the machine in Kram’s lab and found it helpful to maintain their fitness as they recovered, Kram said.

For the study, the researchers retrofitted the G-Trainer with a force-measuring treadmill invented by Kram’s team that charts vertical and horizontal stress load on each foot during locomotion, measuring the variation of biomechanical forces on the legs during running. Ten subjects each ran at three different speeds at various reduced weights, with each run lasting seven minutes. The researchers also measured oxygen consumption during each test, Kram said.

Grabowski likened the effect of the G-Trainer on a runner to pressurized air pushing on the cork of a bottle. “If you can decrease the intensity of these peak forces during running, then you probably will decrease the risk of injury to the runner.”

The G-Trainer is a spinoff of technology originally developed by Rob Whalen, who conceived the idea while working at NASA Ames as a National Research Council fellow to help astronauts maintain fitness during prolonged space flight. While the NASA technology was designed to effectively increase the weight of the astronauts to stem muscle atrophy and bone loss in low-gravity conditions, the G-Trainer reverses the process, said Grabowski.

In the past, sports trainers and researchers have used climbing harnesses over treadmills or flotation devices in deep-water swimming pools to help support the weight of subjects, said Kram. Harnesses are cumbersome, while pool exercises don’t provide sufficient aerobic stimulation and biomechanical loading on the legs, he said.

Marathon world-record holder Paula Radcliffe of Great Britain is currently using a G-Trainer in her high-altitude training base in Font-Remeu, France. Radcliffe is trying to stay in top running shape while recovering from a stress fracture in her femur in time for the 2008 Olympic women’s marathon on Aug. 17, according to the London Telegraph.

Kram and Grabowski have begun a follow-up study of walking using the G-Trainer. By studying subjects walking at various weights and speeds in the machine, the researchers should be able to quantify its effectiveness as a rehabilitation device for people recovering from surgeries, stress fractures and other lower body injuries, Kram said.

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Article adapted by MD Sports from original press release.
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Contact: Rodger Kram
University of Colorado at Boulder

Neuroscience researchers at the Duke-NUS Graduate Medical School in Singapore have shown for the first time what happens to the visual perceptions of healthy but sleep-deprived volunteers who fight to stay awake, like people who try to drive through the night.

The scientists found that even after sleep deprivation, people had periods of near-normal brain function in which they could finish tasks quickly. However, this normalcy mixed with periods of slow response and severe drops in visual processing and attention, according to their paper, published in the Journal of Neuroscience on May 21.

“Interestingly, the team found that a sleep-deprived brain can normally process simple visuals, like flashing checkerboards. But the ‘higher visual areas’ – those that are responsible for making sense of what we see – didn’t function well,” said Dr. Michael Chee, lead author and professor at the Neurobehavioral Disorders Program at Duke-NUS. “Herein lies the peril of sleep deprivation.”

The research team, including colleagues at the University of Michigan and University of Pennsylvania, used magnetic resonance imaging to measure blood flow in the brain during speedy normal responses and slow “lapse” responses. The study was funded by grants from the DSO National Laboratories in Singapore, the National Institutes of Health, the National Institute on Drug Abuse, the NASA Commercialization Center, and the Air Force Office of Scientific Research.

Study subjects were asked to identify letters flashing briefly in front of them. They saw either a large H or S, and each was made up of smaller Hs or Ss. Sometimes the large letter matched the smaller letters; sometimes they didn’t. Scientists asked the volunteers to identify either the smaller or the larger letters by pushing one of two buttons.

During slow responses, sleep-deprived volunteers had dramatic decreases in their higher visual cortex activity. At the same time, as expected, their frontal and parietal ‘control regions’ were less able to make their usual corrections.

Scientists also could see brief failures in the control regions during the rare lapses that volunteers had after a normal night’s sleep. However, the failures in visual processing were specific only to lapses that occurred during sleep deprivation.

The scientists theorize that this sputtering along of cognition during sleep deprivation shows the competing effects of trying to stay awake while the brain is shutting things down for sleep. The brain ordinarily becomes less responsive to sensory stimuli during sleep, Chee said.

This study has implications for a whole range of people who have to struggle through night work, from truckers to on-call doctors. “The periods of apparently normal functioning could give a false sense of competency and security when in fact, the brain’s inconsistency could have dire consequences,” Chee said.

“The study task appeared simple, but as we showed in previous work, you can’t effectively memorize or process what you see if your brain isn’t capturing that information,” Chee said. “The next step in our work is to see what we might do to improve things, besides just offering coffee, now that we have a better idea where the weak links in the system are.”

 

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Article adapted by MD Sports from original press release.
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Contact: Mary Jane Gore
Duke University Medical Center

Other authors of the study include Jiat Chow Tan, Hui Zheng, and Sarayu Parimal of the Cognitive Neuroscience Lab at the Duke-NUS Graduate Medical School; Daniel Weissman of the University of Michigan Psychology Department; David Dinges of the University of Pennsylvania School of Medicine; and Vitali Zagorodnov of the Computer Engineering Department of the Nanyang Technological University in Singapore.