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Research, Science, Sleep, Stanford News

Flashing light at night could help beat jet lag, Stanford study says

Flashing light at night could help beat jet lag, Stanford study says

plane in sunsetThe body will eventually adjust to jet lag, it’s just that it takes time — about an hour a day to be precise. And anyone who has suffered the unpleasant side effects of jet lag – brain fog, body achiness, an overwhelming need for endless pots coffee — might have an interest in speeding the process up.

A new Stanford study suggests that exposing travelers to short bursts of flashing lights the night before a trip while asleep could help speed up the process significantly. In a press release I wrote on the study, which was published today in the Journal of Clinical Investigation, researchers explained how this works at a biological level:

The transfer of light through the eyes to the brain does more than provide sight; it also changes the biological clock. A person’s brain can be tricked into adjusting more quickly to disturbances in sleep cycles by increasing how long he or she is exposed to light prior to traveling to a new time zone.

Light therapy is designed to speed up the brain’s adjustment to time changes. By conducting light therapy at night, the brain’s biological clock gets tricked into adjusting to an awake cycle even when asleep. It’s a kind of “biological hacking” that fools the brain into thinking the day is longer while you get to sleep.

 To determine whether continuous or flashing lights would provide the fastest method of sleep cycle adjustment, researchers had 39 study participants sleep in a lab, exposing some to continuous light for an hour, and others to flashing light for an hour. They found that the flashing light —which most could sleep through just fine— elicited about a two-hour delay in the onset of sleepiness, while those exposed to continuous light, the delay was only 36 minutes.

Jamie Zeitzer, PhD, the senior author of the study, described how flashing-light therapy could be used to adapt to traveling from California to the East Coast: “If you are flying to New York tomorrow, tonight you use the light therapy. If you normally wake up at 8 a.m., you set the flashing light to go off at 5 a.m. When you get to New York, your biological system is already in the process of shifting to East Coast time.”

“This could be a new way of adjusting much more quickly to time changes than other methods in use today,” he told me.

Previously: Cheating jet lag: Stanford researchers develop methods to treat sleep disturbances, Why sleeping in on the weekends may not be beneficial to your health, How sleep acts as a cleaning system for the brain, Study shows altered circadian rhythms in the brains of depressed people, Jet-lag drug is a no go and Jet-lagged hamsters flunk IQ test
Photo by Eric Prado

In the News, Public Health, Sleep

How to tell if you’re sleep deprived

How to tell if you're sleep deprived

mad cartoonAre you chronically cranky or hungry (or, worse, hangry)? Are you clumsy or prone to nodding off during a show? Those are just a few of the signs that you may be sleep-deprived — signs that are hilariously depicted through a series of TV and movie clips in a fun new Bustle piece. The article caught my attention because it includes comments from Stanford sleep expert Rafael Pelayo, MD, (who explains why being short on z’s can make it difficult to fall asleep at one’s normal bedtime), but I also quite like the wise words of writer Chrissa Hardy:

Functioning isn’t thriving, just as surviving isn’t really living. The bare minimum is never the goal, and sleeping the shortest amount of time in order to get through the following day is no way to present your best self to the world.

In other words, go get some sleep.

Previously: Stanford doc gives teens a crash course on the dangers of sleep deprivationStanford docs discuss all things sleepExploring the effect of sleep loss on health and What are the consequences of sleep deprivation?
Photo by Ben Piddington

In the News, Research, Sleep

On narcolepsy, naps, the genetics of sleep (and chocolate?)

On narcolepsy, naps, the genetics of sleep (and chocolate?)

606739059_bff97744c2_zSomeone who studies sleep for a living surely sleeps soundly, right? Maintains a set bedtime and snoozes for a full eight hours?

Not necessarily, a recent interview with Stanford narcolepsy researcher Emmanuel Mignot, MD, PhD shows.

“[I] usually wake up once in the middle of the night. Usually, I go into the kitchen and eat something like a piece of chocolate — always dark chocolate,” Mignot said in an article from Van Winkle’s, a website focused on sleep.

Otherwise, Mignot characterizes his sleep as “a little boring. It’s not great, but it’s not traumatic.”

For his dog, the narcoleptic Chihuahua Watson, however, sleep is something that pounces suddenly, often during a rousing game of fetch. “He’ll go and get the toy and then I’ll try to take it from him — and he just falls asleep. I have to catch him as he falls over,” Mignot said.

Watson’s cataplexy, or a sudden episode of muscle paralysis, is one of the most common symptoms of narcolepsy, a disease characterized by almost constant sleepiness.

In the piece, Mignot also discussed his work to develop a treatment for narcolepsy and his plans to conduct study on the genetics of sleep problems.

Previously: How insufficient sleep can lead to weight gain, Watson, the narcoleptic Chihuahua, demonstrates symptoms on-air and Stumbling upon circadian rhythms
Photo by John Loo

Ask Stanford Med, Sleep, Stanford News

Brains that go bump in the night: Stanford biologist talks about parasomnias

Brains that go bump in the night: Stanford biologist talks about parasomnias

“The witching hour… was a special moment in the middle of the night when every child and every grown-up was in a deep, deep sleep, and all the dark things came out from hiding and had the world all to themselves.”
-Roald Dahl, The BFG

nightmareIn folklore and literature, the sleeping hours represent a state of heightened vulnerability, a time when the “ghoulies and ghosties, and long-leggedy beasties” roam free and wreak havoc. Today, neuroscientists are unraveling the biological underpinnings of nightmares, night terrors, and other sleep disturbances.

Recently, I had the chance to sit down to discuss these nighttime phenomena with biologist H. Craig Heller, PhD, a member of the Stanford Neurosciences Institute and an expert in the neurobiology of sleep.

What are parasomnias and what causes them to occur?

Parasomnias include nightmares, night terrors, and sleepwalking — the really bizarre aspects of sleep.

Normal sleep phasing, timing, and coordination require smooth transitions between wake, non-REM sleep, and REM sleep. When the integration is imperfect, the pathologies of sleep may occur.

For example, sleep paralysis is caused by an inappropriate transition between REM sleep and wakefulness. During REM sleep the cortex is activated, so to keep the body asleep, inputs and outputs are blocked — your body becomes paralyzed. Sleep paralysis occurs when REM paralysis persists as you return to wakefulness. You are coming out of a paralyzed state in which you are freely associating, and this can lead to hallucinations that you’re being restrained.

The opposite can also happen: During REM sleep, motor inhibition can be lost, and you can act out your dreams — which can be violent.

In your mind, what’s the scariest sleep disorder?

Sleepwalking. Sleepwalking occurs during NREM sleep, and in contrast to nightmares or violent movements that can occur during REM sleep, sleep walking is more an extension of normal waking behavior, but you are not aware of what you are doing. As a result, sleep walkers can get into dangerous situations.

In one case, a guy sleepwalked out of his house during winter in Minnesota, before eventually returning to his home and to bed. The next morning, he woke up, pulled back the covers, and found his feet seriously frostbitten. They were a mess. You would think he would be in tremendous pain, but he didn’t wake up.

Also, in cold places in the winter, kids can sleep walk out of the house and freeze to death. In one case a child was found dead in the morning just curled up in a snowdrift immediately outside his house. Some apparent suicides may even be cases of sleepwalking.

You mentioned that people can act out their dreams if the REM sleep paralysis is lifted or not activated – is this phenomenon the same as sleep walking?

No, it’s not the same. Loss of motor inhibition during REM usually results in dramatic, extreme movements, whereas sleep walkers are more likely to act in ways that are simple extensions of normal waking behavior. Sleep walkers may eat and maybe even drive a car and not remember it the next morning. Those with REM sleep disorders are acting out the bizarre context of nightmares.

One of my teaching assistants had a particularly dramatic experience: One night she was dreaming that she was being chased by a giant cockroach; she stood up on her bed and started to run, and she ran right off the bed and into the bureau and broke her back.

In some cases, people dream they are fighting an enemy, so they’ll punch or kick the person in bed with them. There are court cases involving murder and the defense is that the individuals were asleep. Court decisions have gone both ways. In one episode, a woman was dreaming she was being attacked, and when her father came into her room to wake her, she got a gun that was in the bedside drawer and shot him.

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Mental Health, Public Health, Public Safety, Sleep, Stanford News

From A to ZZZZs: The trouble with teen sleep

From A to ZZZZs: The trouble with teen sleep

go_to_bed_fullWhen I recently began working on a story on teen sleep for Stanford Medicine magazine, I was afraid I might not find teens who were troubled by sleep issues and willing to talk about them. I need not have worried: Virtually every teen I encountered had a story to tell about consistently having late nights stressing out over tests or papers or texting friends and cruising the web. It also wasn’t unusual for teens to say that they kept their cell phones on at night in case they got a message from a friend who needed to talk.

Some were tortured by the lack of sleep, often nodding off in class, but said they felt compelled to stay up in order to compete academically in these high-pressure local communities that worship at the altar of academic achievement.

“I’ve heard horror stories of being sleep-deprived,” one 17-year-old told me. “You’re not able to focus on homework, you feel moody and are not able to pay attention in class.”

Another teen reinforced what the National Sleep Foundation found in a recent poll – that 87 percent of American teens are chronically sleep-deprived. “You could probably talk to any teen when they reach their breaking point,” she told me. “You’ve pushed yourself so much and not slept enough and you just lose it.”

In my research, I learned that these students pay a heavy price, potentially compromising their physical and mental health. Study after study in the medical literature sounded the alarm over what can go wrong when teens suffer chronic sleep deprivation: drowsy driving incidents, poor academic performance, anxiety, depression, suicidal thoughts and even suicide attempts.

“I think high school is the real danger spot in terms of sleep deprivation,” Stanford’s William Dement, MD, PhD, the famed sleep researcher, told me. “It’s a huge problem.”

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Cancer, Research, Sleep, Stanford News, Stem Cells, Transplants

Sleep deprivation affects stem cell function, say Stanford scientists

Sleep deprivation affects stem cell function, say Stanford scientists

sleepy mouseWe all know that sleep is important for many biological functions. But I’m still surprised at the breadth of its influence. Today, a former postdoctoral scholar at Stanford, Asya Rolls, PhD, published a fascinating study in Nature Communications showing that blood-forming stem cells from drowsy mice perform more poorly when transplanted into recipient animals. In particular, they are less able to home to the bone marrow, and they generate a smaller proportion of a type of immune cell called a myeloid cell than do stem cells from well-rested mice.

Although the researchers studied only laboratory mice, the possible implications for human transplant recipients (in humans, these procedures are called hematopoietic stem cell transplants, or sometimes bone marrow transplants) are intriguing. As Rolls, who is now an assistant professor at the Israel Institute of Technology, said in our release, “Considering how little attention we typically pay to sleep in the hospital setting, this finding is troubling. We go to all this trouble to find a matching donor, but this research suggests that if the donor is not well-rested it can impact the outcome of the transplantation.”

At Stanford, Rolls worked in the laboratory of psychiatrist and sleep medicine specialist Luis de Lecea, PhD, and she collaborated with Wendy Pang, MD, PhD, and Irving Weissman, MD, director of the Stanford Institute of Stem Cell Biology and Regenerative Medicine, to conduct the research.

Despite the fact that sleep deprivation in the donor reduced the efficacy of their stem cells by about 50 percent, all is not lost. From our release:

Although the effect of sleep deprivation was stark in this study, Rolls and her colleagues found that it could be reversed by letting the drowsy mice catch up on their ZZZs. Even just two hours of recovery sleep restored the ability of the animals’ stem cells to function normally in the transplantation tests.

“Everyone has these stem cells, and they continuously replenish our blood and immune system,” said Rolls. “We still don’t know how sleep deprivation affects us all, not just bone marrow donors. The fact that recovery sleep is so helpful only emphasizes how important it is to pay attention to sleep.”

Previously: In mice, at least, uninterrupted sleep is critical for memory and Bone marrow transplantation: The ultimate exercise in matchmaking
Photo by Eddy Van 3000

Aging, Research, Sleep

Having trouble sleeping? Research suggests spending more time outdoors

Having trouble sleeping? Research suggests spending more time outdoors

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Raise your hand if you didn’t sleep well last night. Findings published in the latest issue of Preventive Medicine show that increasing the amount of time you spend outdoors can improve sleep quality, particularly for men and people over the age of 65.

To better understand the relationship between insufficient sleep and outdoor space, researchers analyzed data from the Centers for Disease Control and Prevention’s Behavioral Risk Factor Surveillance System, which surveyed of more than 250,000 adults in the United States. This information was paired with data from a U.S. Department of Agriculture index that scores the country’s geographical areas for natural amenities, using hours of sunlight, an important factor in regulating a person’s circadian rhythm, and temperature. According to a release:

For men, the relationship between sleep and exposure to green space was much stronger than for women. And males and females 65 and over found nature to be a potent sleep aid, [Diana Grigsby-Toussaint, PhD, said.]

Grigsby-Toussaint noted that living near green landscapes is associated with higher levels of physical activity and that exercise in turn predicts beneficial sleep patterns.

The finding should be a boon for people who are having trouble sleeping as they age. “If there is a way for persons over 65 to spend time in nature, it would improve the quality of their sleep—and their quality of life—if they did so,” Grigsby-Toussaint said.

Researchers added that the findings underscored the importance of preserving nature and providing safe access to nature in urban development.

Previously: Green roofs are not just good for the environment, they boost productivity, study shows, Nature is good for you, right? and Out-of-office autoreply: Reaping the benefits of nature
Photo by Garry Knight

Health Policy, Pediatrics, Research, Sleep

Rethinking middle and high-school success: strategies for creating healthier students

Rethinking middle and high-school success: strategies for creating healthier students

512px-Sleeping_while_studyingMy daughters are still years away from college or even high school, but I’m not looking forward to the high-pressure arena that they look to be from afar. The stress and lack of sleep has to take a toll on students’ health. I was curious, then, to hear about a program developed by researchers from Stanford’s Graduate School of Education called Challenge Success. The program helps parents and schools develop a more even-keeled approach to the high-pressure world that many college-bound middle- and high-schoolers find themselves in.

Last week, the program released Overloaded and Underprepared: Strategies for Stronger Schools and Healthy, Successful Kids, a book that gathers what researchers at Challenge Success have learned in the dozen years the program has been in place. The GSE’s website features a Q&A with two of the book’s authors: Denise Pope, PhD, EdM, a Stanford GSE lecturer and co-founder of Challenge Success, and Maureen Brown, Challenge Success Executive Director.

Below are some highlights of the interview, which is worth reading all the way through:

How are students overloaded today?

Pope: People assume with the new standards and requirements for college admission, that teachers need to cover more topics in class and that kids need to take more courses and do more activities in school and after school to meet expectations for success. This is a confusion between rigor and load. Rigor is real depth of understanding, mastery of the subject matter. That’s what we want. Load is how much work is assigned. Many educators and many parents assume that the more work you assign and the more work students do, the better they will understand it. That is not necessarily the case. For example, we have teachers who teach AP classes and cut their homework load in half, and the kids end up doing as well on the exam. You don’t have to do four hours of homework in order to learn something in depth or to retain it. But four hours of homework can be incredibly damaging physically and emotionally.

. . .

Who should read this book?

Pope: We started writing it for educators, to give a guide to those schools that couldn’t physically partner with us at Challenge Success. The goal was to compile our best practices. But after a little bit of writing, I handed it to my husband (who isn’t an educator) just to see if it made sense. He came back and said, ‘You know, I was really interested as a parent as to why a school would use a block schedule or why so many kids are cheating or what is the purpose of taking an Advanced Placement course.’ So we realized it was actually a book for a much broader audience of people who were interested in the research on some of these practices.

Brown: For example, if parents don’t understand the ‘why’ for certain policies or practices, they can’t help advocate for real systemic change. The book gives parents the ability to ask the right questions at their schools to understand why their school is going down a certain path.

Previously: Excessive homework for high-performing high schoolers could be harmful, study findsWith school bells ringing, parents should ensure their children are doing enough sleeping, Stanford expert: Students shouldn’t sacrifice sleep and Stanford researchers to study effectiveness of yoga-based wellness program at local schools
Photo by Psy3330 W10

Pediatrics, Public Health, Public Safety, Sleep, Stanford News

Rolling through campus and talking sleep with famed researcher William Dement

Rolling through campus and talking sleep with famed researcher William Dement

Dement in shuttle2 (RS) - croppedRenowned sleep researcher William Dement, MD, PhD, is maneuvering his way in his “Sleep and Dreams Mobile” through the Stanford University campus, en route to the Jerry House, site of some of the early, landmark studies in sleep. The house, a sprawling Mediterranean-style dormitory, housed Stanford’s Summer Sleep Camp in the 70s and 80s, where Dement and his colleagues planted the seed for some of the most important findings in the field of sleep among adults and teens.

Three years ago, the house was immortalized with a plaque and a party in which Jeff Chimenti of Grateful Dead fame performed for a crowd of 60 celebrants (the building is named after the Grateful Dead’s Jerry Garcia). Dement, now 85, says he often passed the house on his way to his ever-popular Sleep and Dreams class and thought it was important to mark the spot.

“I’d go by this house and think, ‘What happened here is the biggest thing in sleep disorders.’ So I thought something should be done to create a memorial,” he says, leaning on the banister in the living room of the house.

I’ve asked him to give me a tour of the house as background for a story on teen sleep that I’m writing for the next issue of Stanford Medicine magazine. He points to the backyard of the house, now a barren Lake Lagunita, where young volunteers played volleyball, all the while carrying a nest of wires on their heads to monitor their brain waves. Inside, researchers would monitor the youngsters’ brain activity 24 hours a day to better understand their patterns of sleep.

“The electrodes would stay on their heads because it was too difficult to take them off,” Dement explains. When the volunteers would trudge off to Tresidder Union to go bowling or do other activities, he says, “People would say, ‘Here come the trodes.’”

Dement and his colleagues followed the youngsters for ten successive summers, observing patterns in how their sleep changed as they matured.

A major goal of the study was to confirm the popular belief that as teens get older, they need less sleep. To the researchers’ surprise, they found that as the youngsters aged, the number of hours they slept stayed the same – roughly 9 hours.

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Aging, In the News, Public Health, Sleep

Nothing to snort over: Why snoring should be taken seriously

Nothing to snort over: Why snoring should be taken seriously

6258904896_ec4a6f155a_zIt’s the middle of the night—or maybe the middle of the day—and all seems well. Then, you hear it: a low, rumbling, animalistic sound. It could be a snort or a growl or even a snarl. But it’s not an animal at all. It’s a person who is snoring far too loudly for your liking, and the sound only seems to be getting worse.

It’s safe to say we all know someone who snores – or we may even do it ourselves. A Huffington Post article puts a spotlight on snoring and features Stanford’s Rafael Pelayo, MD, who explains why it occurs, why it becomes increasingly worse with age, and, most importantly, why it could signal a potentially serious health problem.

“Think of fire and a fire alarm,” Pelayo says. “The snoring is the alarm. If there’s a fire and the fire alarm goes off and I disconnect the alarm, it doesn’t mean I put out the fire. The fire could still be burning.”

Snoring could be a symptom of sleep apnea, a disorder in which a person’s breathing repeatedly stops and starts during sleep. Apnea is a legitimate medical issue that can be harmful if gone unchecked, and Pelayo encourages anyone who snores to get tested for it.

Alex Giacomini is an English literature major at UC Berkeley and a writing and social media intern in the medical school’s Office of Communication and Public Affairs.

Previously: New recommendation: Adults need at least 7 hours of sleep each night, Why untreated sleep apnea may cause more harm to your health than feeling fatigued and How insufficient sleep can lead to weight gain 
Photo by Marc Lewis

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