Bats, birds, box turtles, humans and many other animals share at least one thing in common: They sleep. Humans, in fact, spend roughly one-third of their lives asleep, but sleep researchers still don’t know why.
According to the journal Science, the function of sleep is one of the 125 greatest unsolved mysteries in science. Theories range from brain “maintenance” — including memory consolidation and pruning — to reversing damage from oxidative stress suffered while awake, to promoting longevity. None of these theories are well established, and many are mutually exclusive.
Researchers develop computational method for aligning internal body clock with local, environmental time.
Traveling across several times zones can cause an individual to experience jet lag, which includes trouble sleeping at night and trouble remaining awake during the day.
New research conducted by Charles Wingo and his colleagues, at the University of Florida, Gainsville, suggests a link between the circadian rhythm and control of sodium (salt) levels in mice.
The hormone aldosterone regulates levels of sodium in the blood and thereby helps control blood pressure.
Experts have long suspected that part of the process of turning fleeting short-term memories into lasting long-term memories occurs during sleep. Now, researchers at the RIKEN-MIT Center for Neural Circuit Genetics of MIT’s Picower Institute for Learning and Memory have shown that mice prevented from “replaying” their waking experiences while asleep do not remember them as well as mice who are able to perform this function.
The work, which has a profound implication in the century-old search for the purpose of sleep, will be reported in the June 25, 2009 issue of Neuron.
The eyes may be the window into the soul, but they may also contain important medical information. According to research findings presented at the American Thoracic Society’s 105th International Conference in San Diego, patients who have been diagnosed with both diabetes and retinopathy should also be screened for obstructive sleep apnea (OSA).
“We know from our earlier research that 23 percent of men with type 2 diabetes have OSA and this is under-recognized and under-treated,” said Sophie D. West, M.D., of the Oxford Centre for Respiratory Medicine in the United Kingdom, who led the research. “This study suggests that OSA is linked to retinopathy in type 2 diabetes.”
Sleep experts know that the mental clarity lost because of a few sleepless nights can often be restored with a good night’s rest. Researchers have identified a key molecular mechanism that regulates the brain’s ability to mentally compensate for sleep deprivation.
Working with mice, they found that a molecule called an adenosine receptor is necessary for sleep-restricted animals to attain adequate levels of slow-wave activity in the brain once normal sleep resumes. It is this increase in slow-wave activity, or SWA, during rebound sleep that helps restore normal working memory and attention skills to the sleep-deprived.
For many animals, sleep is a risk: foraging for food, mingling with mates, and guarding against predators just aren’t tasks possible while snoozing.
Scientists are wondering how, then, has this seemingly life-threatening behavior remained constant among various species of animals?
Scientists have known for a long time now that messing with the 24-hour circadian rhythm plays havoc with the lives and health of medical, military and airline personnel, factory employees, and travelers.
A new paper by University of Notre Dame biologist Giles Duffield and a team of researchers sheds new light on circadian timing systems and focuses on a key gene that seems to regulate the response of the circadian clock to light signals.
Researchers from Johns Hopkins Bayview Medical Center Bariatric Surgery Clinic have found that the chronic intermittent hypoxia that often characterizes obstructive sleep apnea, a common form of sleep-disordered breathing, is independently linked to the progression of liver disease.
In this study, researchers recruited 90 severely obese patients presenting for bariatric surgery at without known diagnoses of obstructive sleep apnea. Each patient underwent a sleep study and blood tests for markers of liver function, insulin resistance, and systemic inflammation.
