Sleep deprivation adversely affects automatic, accurate responses and can lead to potentially devastating errors, a finding of particular concern among firefighters, police officers, soldiers and others who work in a sleep-deprived state, University of Texas at Austin researchers say. Psychology professors Todd Maddox and David Schnyer found moderate sleep deprivation causes some people to shift from a faster and more accurate process of information categorization (information-integration) to a more controlled, explicit process (rule-based), resulting in negative effects on performance. The researchers examined sleep deprivation effects on information-integration, a cognitive operation that relies heavily on implicit split-second, gut-feeling decisions. "It's important to understand this domain of procedural learning because information-integration - the fast and accurate strategy - is critical in situations when solders need to make split-second decisions about whether a potential target is an enemy soldier, a civilian or one of their own, " Maddox said.
A police officer who works the night shift, typically from 8 p.m. to 4 a.m., already is at a disadvantage when it comes to getting a good "night's" sleep. Add frequent overtime to that schedule, and an officer may be climbing into bed as the sun comes up, setting the stage for short and unrestful slumber. A new study published in the current issue of Archives of Environmental & Occupational Health (vol. 64, No. 3) shows that this combination of night work, overtime and shortened sleep can contribute to the development among police officers of the metabolic syndrome, a combination of unhealthful factors that increase the risk of cardiovascular disease (CVD), primarily heart disease and stroke. John M. Violanti, PhD, research associate professor in UB's Department of Social and Preventive Medicine in the School of Public Health and Health Professions, is first author on the paper, and received significant contributions from biostatisticians in the CDC's National Institute for Occupational Safety and Health (NIOSH).
A baby's sleep position is the best predictor of a misshapen skull condition known as deformational plagiocephaly - or the development of flat spots on an infant's head - according to findings reported by Arizona State University scientists in the December issue of the journal Pediatrics. Analyzing the largest database to date, more than 20, 000 children, the ASU researchers found that the number of babies who have developed flat-headedness has dramatically increased since 1992. The increase coincides with the American Academy of Pediatrics launch of a "Back to Sleep" educational campaign that recommended parents place their infants on their backs to reduce the risk of Sudden Infant Death Syndrome. "We looked at a number of risk factors, but the largest factor was the sleep position of the baby, " said Brian Verrelli, an assistant professor in ASU's School of Life Sciences and researcher in the Center for Evolutionary Functional Genomics at the Biodesign Institute. The condition is thought to occur when babies spend too much time in one position.
Sleep apnea is common in individuals who receive a kidney transplant and is associated with increased risk of high blood pressure, heart disease or stroke, according to a study appearing in an upcoming issue of the Clinical Journal of the American Society Nephrology (CJASN). Researchers found that kidney transplant patients are just as likely to have this sleep disorder as dialyzed kidney disease patients who are on the transplant waiting list. Therefore, both types of patients who have sleep apnea should be considered at high risk for developing serious heart-related complications. Cardiovascular disease is the most common cause of death in individuals who receive kidney transplants, and doctors monitor transplant recipients for high blood pressure, or hypertension, and other signs of heart trouble. Obstructive sleep apnea occurs when an individual stops breathing momentarily during sleep due to obstruction of the airway and has been linked to hypertension. Miklos Zsolt Molnar, MD, PhD (Semmelweis University, Budapest, Hungary), and his colleagues studied the prevalence of sleep apnea in kidney transplant patients and the effects the condition had on their cardiovascular risk.
They were in a deep sleep, yet sounds, such as a teakettle whistle and a cat's meow, somehow penetrated their slumber. The 25 sounds presented during the nap were reminders of earlier spatial learning, though the Northwestern University research participants were unaware of the sounds as they slept. Yet, upon waking, memory tests showed that spatial memories had changed. The participants were more accurate in dragging an object to the correct location on a computer screen for the 25 images whose corresponding sounds were presented during sleep (such as a muffled explosion for a photo of dynamite) than for another 25 matched objects. "The research strongly suggests that we don't shut down our minds during deep sleep, " said John Rudoy, lead author of the study and a neuroscience Ph.D. student at Northwestern. "Rather this is an important time for consolidating memories." Most provocatively, the research showed that sounds can penetrate deep sleep and be used to guide rehearsal of specific information, pushing people's consolidation of memories in one direction over another.
Restless leg syndrome (RLS) is a form of insomnia characterized by an overwhelming urge to move the legs when they are at rest, especially during sleep. RLS affects about 10% of the people in the U.S. It runs in families and may have a genetic component. Recent research has found that people with restless leg syndrome are deficient in the mineral magnesium. According to the National Sleep Foundation, almost six out of ten Americans report having insomnia and sleep problems at least a few nights a week. Other types of insomnia include sleep apnea, which involves interrupted breathing and snoring during the night; narcolepsy - which causes people to fall asleep throughout the daytime; insomnia from hormone fluctuations such as with menstruation or menopause; and insomnia from the use of medications, caffeine or alcohol. Those who have restless leg syndrome experience unpleasant sensations in the legs described as creeping, crawling, tingling, pulling, or painful. These sensations usually occur in the calf area but may be felt anywhere from the thigh to the ankle.
A study in the Dec. 15 issue of the Journal of Clinical Sleep Medicine indicates that significant associations exist between parent-reported insomnia symptoms and medical complaints of gastrointestinal regurgitation and headaches in young school-aged children. Results of multivariate regression analysis show that parent-reported insomnia was 3.3 times more likely in children with gastrointestinal regurgitation and 2.3 times more likely in children with headaches. Nineteen percent of children met the criteria for insomnia, which was defined as often having trouble falling asleep and/or waking up often in the night. Gastrointestinal regurgitation was reported in 7.5 percent of children with insomnia and two percent of children who did not have sleep disturbances. Headaches were reported in 24.4 percent of children with insomnia and 13.2 percent of children without disturbed sleep. Lead author Ravi Singareddy, MD, assistant professor in the department of psychiatry at Penn State College of Medicine in Hershey, Pa.
The advice of a pediatrician to place infants on their backs to sleep appears to be the single most important motivator in getting parents to follow these recommendations and a key reason that the rate of sudden death syndrome (SIDS) has plummeted since the "Back to Sleep" campaign was launched in 1994, says a UT Southwestern researcher. Multiple studies have shown that placing infants on their backs to sleep limits the risk of SIDS, the leading cause of death among children in the U.S. under the age of 1. In a study available online and in the December issue of Archives of Pediatric and Adolescent Medicine, researchers, including Dr. George Lister, chairman of pediatrics at UT Southwestern and an author of the study, identify three reasons a caregiver might or might not follow the recommendation: concerns for an infant's comfort; fear that the infant might choke while sleeping on his or her back; and whether a physician advised the caregiver to always place an infant on his or her back to sleep.
A study in the Dec. 15 issue of the Journal of Clinical Sleep Medicine shows that being overweight or obese increases the risk for developing obstructive sleep apnea (OSA) in adolescents but not in younger children. Results indicate that the risk of OSA among Caucasian adolescents 12 years of age and older increased 3.5 fold with each standard-deviation increase in body mass index (BMI) z-score, while the risk of OSA did not significantly increase with increasing BMI among younger children. According to the authors, the results suggest that the increase in risk among overweight and obese adolescents may result from developmental changes such as reductions in upper airway tone and changes to anatomic structures. "These results were a little surprising to us initially, as obesity is generally considered to increase the risk of sleep apnea amongst all children, " said principal investigator Mark Kohler, PhD, research fellow at the Children's Research Centre at the University of Adelaide in Australia.
MSc (Tech) VГ inГ Virtanen has developed a method for analysing snoring sounds by using a PC with a microphone connection and a wireless microphone. The objective was to create an application that could be used at home to monitor snoring. By utilizing this technology, researchers from Tampere University of Technology and the University of Helsinki have investigated sleep disorders and further refined related screening technologies. The collaboration has already spawned the smart alarm clock HappyWakeUp that was launched last year. It is the first health-promoting mobile phone application in the world. In spring, the research team received funding from the Finnish Funding Agency of Technology and Innovation Tekes to create a sleep diagnostics service concept. Based on the technology developed by Virtanen and his colleagues, the team created a service that enables at-home screening of sleep disorders. The service was recently released on the Internet. "People can record their sleep all through the night with a mobile phone or an MP3 player.