麻豆影院

New CU 麻豆影院 research explores effects of too little sleep and 鈥榗ircadian misalignment鈥櫶�

If you are a person who is proud of burning the candle at both ends鈥攕ay, a college student, first responder or military personnel鈥攁nd surviving on less than optimal sleep, here鈥檚 a message you might not want to hear: You can鈥檛 fool Mother Nature.

If you aren鈥檛 getting enough sleep鈥�7 hours is the average minimum for adults鈥攐r not sleeping at night, when the body鈥檚 long-evolved, natural circadian rhythms say it鈥檚 time to sleep, you and your brain aren鈥檛 performing to your maximum capability on many functions, including reaction times and simple cognition, according to current and newly published research from the听Sleep and Chronology Laboratory听at the 麻豆影院.

鈥淓veryone is vulnerable,鈥� says Kenneth P. Wright, Jr., professor of integrative physiology at CU 麻豆影院 and the director of the Sleep and Chronology Laboratory. 鈥淭here is no such thing as a superhuman who is not vulnerable.鈥�

And to study that vulnerability, Wright and the rest of the lab, along with colleagues from CU 麻豆影院, Northwestern University and the University of California, San Diego, are hard at work researching the impact of sleep deprivation and 鈥渃ircadian misalignment,鈥� thanks to a prestigious U.S. Navy Multi-University Research Initiative grant.听听

The grant supports an ongoing project, which also recently saw a published paper in Oxford University鈥檚 Sleep Research Society, to examine the impact of circadian misalignment and sleep disruption on the human microbiome, Wright says.听

More than 40 percent of U.S. military personnel report sleeping five hours or less per night and are often required to sleep at times out of alignment with natural circadian rhythms. Meanwhile, firefighters in the Western United States routinely work 48-hour shifts and 20 percent of the U.S. population does shift work at night or in the early morning hours. Students, too, are known to pull all-nighters.听

鈥淚t鈥檚 not just the military,鈥� Wright says. 鈥淭hink about medical residents, firefighters, police officers, paramedics. Being awake at night goes against our fundamental biology. 鈥� Long work hours and being awake at night just does not make sense from a health and safety perspective.鈥�

According to the paper, 鈥淭rait-like vulnerability of higher-order cognition and ability to maintain wakefulness during combined sleep restriction and circadian misalignment,鈥� sleep restriction and circadian misalignment can have immense health, performance and safety consequences, including, 鈥渞educed effectiveness, efficiency, resilience and readiness, a greater risk of motor vehicle crashes and injuries, higher rates of posttraumatic stress disorder and risky health behaviors in military personnel, more safety violations and citizen complaints for police officers, and greater risk of metabolic disease and cancer.鈥�

To get these results, the team ran 20 healthy adults (average age 25.7) through a sleep wringer.听

In an effort to capture data that would illuminate the effects of longer-term sleep deprivation and circadian misalignment, the subjects completed a 39-day protocol: Two weeks of monitored sleep at home; four days in the lab, including one 鈥渟leep opportunity鈥� of eight hours, followed by two nights of just three hours of sleep; three days of unscheduled sleep at home; cognitive testing; rinse, and repeat.

Many similar studies focus on just one or two tasks, but in order to assess 鈥渕ultiple cognitive domains,鈥� subjects were asked to perform a number of functions, including reaction time, math problems, and tasks to measure executive function, such as locating a car in a large parking lot or a child on a playground. They also were tested on their ability to stay awake.听

鈥淲e put them in a sleep-conducive environment, their head at a 35-degree angle in a chair like a La-Z-Boy, we dim the lights, and they sit there and try to stay awake,鈥� Wright says.听

Wright鈥攁n unabashed proselytizer for good 鈥渟leep hygiene鈥濃�攕ays the results demonstrate clear negative impacts of circadian misalignment and sleep deprivation on cognitive function. The research points to a need to take the problem seriously and 鈥減ersonalize countermeasures,鈥� since different people and different situations may call for different tools to mitigate the problem.

In the broadest sense, Wright says, there is a need for more sleep education and improvement of sleep environments for everyone, not just military personnel, first responders and the like. And he believes sleep should become a basic biomarker during doctor visits, alongside blood pressure and heart rate.

More specifically, Wright says managers should pay closer attention to research showing marked differences in cognitive performance when workers are sleep deprived, particularly if they work night or early-morning hours. For example, first responders who work a night schedule should be given more time off to recover.听

Schools should take sleep into account when scheduling and schools should educate students鈥攖omorrow鈥檚 parents鈥攁bout sleep hygiene鈥攖he importance of natural daylight, for example, and limiting light before bedtime, he says.

Enhanced, appropriate lighting, such as more sunlight, has been shown to improve outcomes for dementia patients and infants in intensive-care units, Wright says.听

鈥淎rchitects, urban planners and government decision makers can all use light to promote health,鈥� he says.

Humans are the only species with the ability to create artificial light and thereby interfere with its own natural circadian rhythms. But with only about a century of widespread artificial light under its belt, Wright says,听Homo sapiens听hasn鈥檛 had nearly enough time to adapt. People may not know it, but sleep hygiene has serious long-term implications for human health.

鈥淥ur biology has evolved over hundreds of thousands of years, so that is a blink in the eye of evolution. Our biology is hard-wired to evolve with the cycle of the sun,鈥� he says.

Given the American tendency to work long hours and, often, skimp on sleep, changing habits may seem like an uphill battle. But Wright sees a parallel in smoking.

鈥淲e鈥檙e at the point now where we were with smoking. We used to think it was OK; doctors smoked. Then we started to recognize there were some issues and we realized, 鈥極K, smoking wasn鈥檛 good,鈥欌�� he says. 鈥淭hat鈥檚 where we are now with sleep. Smoking kills you decades later, as do poor diet and physical inactivity. It鈥檚 the same thing with sleep loss. This is an opportunity to improve sleep health in the population.鈥澨�