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By Nicholas Bakalar Night owls may be at greater risk for depression than early birds. Previous studies have found a link between a person’s unique circadian rhythm, or chronotype, and depression, but none were able to tell whether sleep habits were a cause or an effect of the disease. This new prospective study, in the Journal of Psychiatric Research, is a step closer to establishing causality. Researchers gathered health and behavioral data on 32,740 women whose average age was 55. Each categorized herself as a definite evening or morning type, a somewhat morning or evening type, or neither. All were free of depression at the start of the study, and over the following four years 2,581 of them developed depression, defined by antidepressant use or a clinical diagnosis. After adjusting for marital status, living alone, being retired, alcohol consumption and other variables, the researchers found that compared to the intermediate types, morning people were 12 percent less likely to develop depression, and night owls 6 percent more likely to develop it. The relationship was linear: the more a woman tended toward the night-owl type, the more likely she was to develop depression. “The effect is modest, a modest association for chronotype and incident depression,” said the lead author, Céline Vetter, an assistant professor at the University of Colorado. “But the overall pattern remains constant. We need to get much deeper into what the genetic and environmental contributions are between mood and chronotype.” © 2018 The New York Times Company

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 25113 - Posted: 06.21.2018

By Julia Jacobs Humans, it turns out, can annoy more than just one another. In fact, some animal populations are escaping their Homo sapien cohabitants by sleeping more during the day, a new study finds. Mammals across the globe are becoming increasingly nocturnal to avoid humans’ expanding presence, according to the study, published Thursday in Science magazine. The findings show that humans’ presence alone can cause animals across continents — including coyotes, elephants and tigers — to alter their sleep schedules. “We’re just beginning to scratch the surface on how these behavioral changes are affecting entire ecosystems,” said Kaitlyn Gaynor, an ecologist and graduate student in environmental science at the University of California, Berkeley, who led the study. Previous research has found that mammals went from being noctural to being active during both day and night about 65.8 million years ago, roughly 200,000 years after most dinosaurs went extinct. “Species for millions of years have been adapting to diurnal activity, but now we’re driving them back into the night and may be driving natural selection,” Ms. Gaynor said in an interview. The researchers compiled data from 76 studies of 62 species living on six continents in reaching their conclusions. On average, human disruption is making these animals 1.36 times more nocturnal, according to the study. “For example,” it says, “an animal that typically split its activity evenly between the day and night would increase its proportion of nocturnal activity to 68 percent of total activity near human disturbance.” In California’s Santa Cruz mountains, for example, coyotes are opting to sleep more during the day in response to recreational human activities such as hiking and bicycling. As a result, coyotes are eating more nocturnal prey, whose waking hours match up more closely with theirs. Recent research such as this was used to provide data for the new study, Ms. Gaynor said. © 2018 The New York Times Company

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 25093 - Posted: 06.15.2018

By Nicholas Bakalar Bedtime reading with a tablet or smartphone can interfere with a good night’s sleep, some studies and many anecdotal reports suggest. Now researchers have conducted a small experiment to test the idea. Scientists had nine people spend 10 nights in a sleep laboratory. For five consecutive nights, they read before sleep with an iPad; then they read print for five nights. In both scenarios, they read in a dimly lit room until they felt ready to go to sleep. The experiment, described in Physiological Reports, found that when people used iPads instead of reading print, they selected a later bedtime and had a later sleep onset. They also had suppressed levels of melatonin, the hormone that regulates sleep, and delayed time to melatonin secretion. Periods of REM sleep — the rapid eye movements of the dreaming stage of sleep — were reduced when they used the iPad rather than printed material. The volunteers also reported feeling less sleepy in the evening, and less alert in the morning after using the electronic device. “These devices are not benign,” said a co-author of the study, Jeanne F. Duffy, a neuroscientist at Brigham and Women’s Hospital in Boston. “They have biological effects on us. They can be bad for adults, but really bad for kids and adolescents who already don’t get enough sleep.” © 2018 The New York Times Company

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 25023 - Posted: 05.26.2018

/ By Lynne Peeples Reaching behind a low bookshelf slightly taller than a typical 5-year-old — and one topped with a Seattle Seahawks gnome and stuffed kangaroo — Sara Barbee presses a button labeled “Alert.” Intense bluish light fills her classroom, and nearly all 17 kindergarteners respond with a collective “Whoooaaaaa.” Barbee, their teacher here at Renton Park Elementary School, walks back to the front of the classroom and ushers the students to sit “crisscross applesauce” on the perimeter of a brightly colored alphabet rug. Front-and-center rests a water tank atop a small blue table, which Barbee uses to teach her students about the buoyancy of objects in water. Indeed, it’s not the buoyancy lesson that has drawn me to this school just outside of Seattle, but those funky new lights, which are designed to mimic the shifting colors and intensities of the rising and setting sun. Scientists believe that exposure to bright, blue-rich white light during the day, and to softer, amber hues at night, helps restore the human body’s natural circadian rhythm, a deeply ingrained, physiological drumbeat that, many experts argue, has been disrupted to ill-effect by our constant exposure to standard incandescent or fluorescent lighting — and more recently, to the relentless glow of electronic screens. These are not, of course, new ideas, and doctors have long prescribed light boxes and related paraphernalia for seasonal affective disorder and other forms of depression. But it’s only now, proponents say — amid innovations in light-emitting diode, or LED, technology; amid calls for more energy-efficient lighting infrastructure overall; and amid a renaissance in scientific understanding of how human eyes, brains, and internal clocks interrelate — that a public health revolution, driven by more thoughtful lighting infrastructure, has the potential to unfold. Copyright 2018 Undark

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 25003 - Posted: 05.21.2018

Nicola Davis People who experience disrupted 24-hour cycles of rest and activity are more likely to have mood disorders, lower levels of happiness and greater feelings of loneliness, research suggests. While the study does not reveal whether disruptions to circadian rhythms are a cause of mental health problems, a result of them or some mixture of the two, the authors say the findings highlight the importance of how we balance rest and activity. “Because people have these 24-hour patterns of living nowadays and because by 2050 two-thirds of the world’s population will live in cities where circadian disruption is much more likely, it is quite a big public health issue. How do we take account of our natural patterns of rest and activity and how do we design cities or jobs to protect people’s mental health?” said Daniel Smith, professor of psychiatry at the University of Glasgow and lead author of the research. Writing in the journal Lancet Psychiatry, a team of researchers from Scotland, Ireland and Sweden report how they carried out the largest study of its kind to date by harnessing data from the UK BioBank, a research endeavour that has collected health information on 500,000 participants, aged between 37 and 73, since 2006. To explore the link between mental health and the 24-hour cycles of sleep and activity known as circadian rhythms, the team looked at data from more than 91,000 participants who had worn a wrist-based activity tracker for a week at some point between 2013 and 2015. © 2018 Guardian News and Media Limited

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 24988 - Posted: 05.17.2018

Lynne Peeples Carole Godain remembers a lot of the little details from the clinical trial she took part in nine years ago. There was the blue button she pushed to get her chemotherapy drugs, and the green light that came on to confirm that the medication was dripping into her veins. Then, of course, there was the hour — 10:00 p.m. without fail, for every treatment. By all accounts, Godain’s own time was running short. The first treatment for her colon cancer had failed, and her last body scan had revealed 27 tumours growing inside her liver. So the psychologist from Tours, France, jumped at the opportunity to take part in a trial at Paul Brousse hospital in Villejuif, which aimed to test whether delivering drugs at a specific time of day might make them more effective or reduce their toxic side effects. Ideally, it would accomplish both. “I was interested in increasing my chances of being cured,” says Godain. Today, at the age of 43, she is cancer-free. And Francis Lévi, the oncologist who treated Godain, says that although such an amazing result is anomalous, emerging evidence should encourage more interest in the concept of chronotherapy — scheduling treatments so that they provide the most help and do the least harm. More than four decades of studies describe how accounting for the body’s cycle of daily rhythms — its circadian clock — can influence responses to medications and procedures for everything from asthma to epileptic seizures. Research suggests that the majority of today’s best-selling drugs, including heartburn medications and treatments for erectile dysfunction, work better when taken at specific times of day. “When you give a medication, you always know the dose,” says Lévi, who also now works at Warwick Medical School in Coventry, UK, where he leads a team associated with INSERM, the French national biomedical research agency. “We have found that the timing is sometimes more important than the dose.” © 2018 Macmillan Publishers Limited

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24877 - Posted: 04.18.2018

By NICHOLAS BAKALAR Morning people may live longer than night owls, a new study suggests. Researchers studied 433,268 people, aged 38 to 73, who defined themselves as either “definite morning” types, “moderate morning” types, “moderate evening” types or “definite evening” types. They followed their health for an average of six-and-a-half years, tracking cause of death with death certificates. The study is in Chronobiology International. After controlling for age and sex, smoking, body mass index, sleep duration and other variables, they found that compared with “definite morning” types, “definite evening” types had a 10 percent increased risk of dying from any cause. Each increase from “morningness” to “eveningness” was associated with an increased risk for disease. Night owls were nearly twice as likely as early risers to have a psychological disorder and 30 percent more likely to have diabetes. Their risk for respiratory disease was 23 percent higher and for gastrointestinal disease 22 percent higher. The lead author, Kristen L. Knutson, an associate professor of neurology at Northwestern University, said that while being a night owl is partly genetic, people can make adjustments — gradually making bedtime earlier, avoiding using smartphones before bed, and eventually moving themselves out of the “night owl zone.” Although the reasons for their increased mortality remain unclear, she said, “Night owls should know that there may be some health consequences.” © 2018 The New York Times Company

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24854 - Posted: 04.12.2018

To understand the link between aging and neurodegenerative disorders such as Alzheimer’s disease, scientists from the National Institutes of Health compared the genetic clocks that tick during the lives of normal and mutant flies. They found that altering the activity of a gene called Cdk5 appeared to make the clocks run faster than normal, and the flies older than their chronological age. This caused the flies to have problems walking or flying later in life, to show signs of neurodegeneration, and to die earlier. “We tried to untangle the large role aging appears to play in some of the most devastating neurological disorders,” said Edward Giniger, Ph.D., senior investigator at the NIH’s National Institute of Neurological Disorders and Stroke and the senior author of the study published in Disease Models & Mechanisms. “Our results suggest that neurodegenerative disorders may accelerate the aging process.” On average, the normal flies in this study lived for 47 days. To create a genetic clock, Dr. Giniger’s team measured the levels of every gene encoded in messenger RNA molecules from cells from the heads and bodies of flies at 3, 10, 30, and 45 days after birth. This allowed the researchers to use advanced analysis techniques to search for the genes that seemed to be sensitive to aging, and create a standard curve, or timeline, that described the way they changed. When they performed the same experiments on 10-day-old mutant flies and compared the results with the standard curve, they found that the flies were “older” than their chronological age. Altering Cdk5 activity made the brains of the flies appear genetically to be about 15 days old and their bodies to be about 20 days old.

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24748 - Posted: 03.14.2018

Patricia Neighmond As the months grow colder and darker, many people find themselves somewhat sadder and even depressed. Bright light is sometimes used to help treat the symptoms of seasonal affective disorder, or SAD. Researchers are now testing light therapy to see if it also can help treat depression that's part of bipolar disorder. It's unclear how lack of light might cause the winter blues, although some suggest that the dark days affect the production of serotonin in the skin. The idea with light therapy for depression is to replace the sunshine lost with a daily dose of bright white artificial light. (Antidepressants, psychotherapy and Vitamin D help, too, according to the National Institute of Mental Health.) The light box is actually more like a screen, the size of your average desktop computer. Some people call it a "happy box." To test its usefulness in treating bipolar disorder, researchers at the Feinberg School of Medicine, Northwestern University enrolled 46 patients who had at least moderate bipolar depression. Half of participants were assigned to receive bright light therapy. The other half received a dim red placebo light. They also kept taking their regular medication. © 2017 npr

Related chapters from BN8e: Chapter 16: Psychopathology: Biological Basis of Behavior Disorders; Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 12: Psychopathology: The Biology of Behavioral Disorders; Chapter 10: Biological Rhythms and Sleep
Link ID: 24368 - Posted: 11.27.2017

Mariah Quintanilla WASHINGTON, D.C. — If it takes you a while to recover from a few lost hours of sleep, be grateful you aren’t an orb weaver. Three orb-weaving spiders — Allocyclosa bifurca, Cyclosa turbinata and Gasteracantha cancriformis — may have the shortest natural circadian rhythms discovered in an animal thus far, researchers reported November 12 at the Society for Neuroscience’s annual meeting. Most animals have natural body clocks that run closer to the 24-hour day-night cycle, plus or minus a couple hours, and light helps reset the body’s timing each day. But the three orb weavers’ body clocks average at about 17.4, 18.5 and 19 hours respectively. This means the crawlers must shift their cycle of activity and inactivity — the spider equivalent of wake and sleep cycles — by about five hours each day to keep up with the normal solar cycle. “That’s like flying across more than five time zones, and experiencing that much jet lag each day in order to stay synchronized with the typical day-night cycle,” said Darrell Moore, a neurobiologist at East Tennessee State University in Johnson City. “Circadian clocks actually keep us from going into chaos,” he added. “Theoretically, [the spiders] should not exist.” For most animals, internal clocks help them perform recurring daily activities, like eat, sleep and hunt, at the most appropriate time of day. Previous studies have shown that animals that are out of sync with the 24-hour solar cycle are usually less likely to produce healthy offspring than those that aren’t. |© Society for Science & the Public 2000 - 2017.

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24328 - Posted: 11.15.2017

By Angela Clow, Nina Smyth, October is a dismal time of year. The clocks go back, which accelerates the onset of darker evenings and the “shorter days” inevitably lead to calls for the tradition of putting clocks forward or backward to stop. Of course, the annual return to Greenwich Mean Time (GMT) from British Summer Time (BST) doesn’t make the days any shorter, it merely shifts an hour of available daylight from the evening to the morning. For many, lighter evenings are a priority and little attention is given to the benefits of lighter mornings. Arguments over clock changes tend to revolve around benefits for easier travel in lighter evenings. Nevertheless research suggests that holding onto lighter mornings might have hitherto unforeseen advantages. Light in the morning – more than any other time of day – leads to powerful brain-boosting effects, helping us to function as best we can, despite the approaching winter. All life on Earth has evolved around the 24-hour cycle of light and dark. An obvious sign is our desire for night-time sleep, but most biological functions are fine-tuned around day and night. Our bodies are honed to environmental light via a biological chain reaction. Light intensity is detected by special cells in the retina and this information is relayed to the internal body clock, located deep in a part of the brain called the suprachiasmatic nucleus. This sits in the hypothalamus, responsible for regulation of internal body processes using the endocrine system, which is linked to hormone secretion, via the pituitary gland. We are unaware of these light messages as they have nothing to do with conscious vision. Their sole job is to internalise information about environmental light intensity. © 2017 Scientific American,

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24261 - Posted: 10.30.2017

Nicola Davis Patients undergoing open heart surgery in the afternoon have a lower risk of potentially fatal complications than those undergoing operations in the morning, new research suggests. The study found that events including heart attacks and heart failure were less common among those who had undergone a valve replacement operation in the afternoon. The finding appears to be linked to the ability of the heart tissue to recover after being starved of blood supply during surgery – an effect the researchers say is influenced by the cells’ biological or “circadian” clock. Overweight patients less likely to die in hospital after heart operations Read more While the study suggests patients might fare better if they undergo afternoon surgery, Professor David Montaigne, first author of the research from the University of Lille in France, said it also highlighted another approach to reduce complications. “We have to find a drug that can alter the circadian clock to induce a jet lag,” he said, noting that it could also help to improve patient outcomes for heart attacks and organ transplantation. Writing the in Lancet, Montaigne and colleagues report how they looked at the outcomes of 596 patients, half of whom had valve surgery in the morning, and half in the afternoon. While 18% of morning surgery patients experienced a major cardiac event – such as a heart attack or heart failure –in the following 500 days, only 9% of those who had afternoon surgery experienced such events. © 2017 Guardian News and Media Limited

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24251 - Posted: 10.27.2017

By DOUGLAS QUENQUA Bad news, bears. Hibernation is no longer the coolest thing animals do to survive the winter. As cold weather approaches, tiny mole-like creatures known as red-toothed shrews will shrink their own heads, reducing their skull and brain mass by as much as 20 percent, according to new research published Monday in Current Biology. When warm weather returns, they will regrow the region nearly to its original size, giving new meaning to the phrase “spring ahead.” Though it is not yet clear why the shrews go down a few sizes for the winter, the authors of the study speculate that the reduced head and brain size helps them conserve energy when resources are scarce. “These tiny mammals cannot migrate long distances to avoid winter, nor can they enter any kind of energy-saving state” like hibernation, said Javier Lazaro, a doctoral student at the Max Planck Institute for Ornithology in Germany and an author of the study. They also have high metabolic rates and very little fat stored in their bodies. “Therefore, they starve within a few hours if they do not hunt constantly.” The researchers say the shrinkage is a survival strategy. “Brain tissue is energetically very expensive, so reducing overall brain size might decrease energy demands and thus food requirements,” he said. The shrews’ reduction in size doesn’t only affect the head. Several major organs lose mass in winter, and the spine shortens, as well. Overall, the shrews in the study reduced their body mass by about 18 percent from July to February. Previous research had hinted that all shrew species might undergo a reduction in body and head mass during the winter. There is even a term for it, Dehnel’s Phenomenon, named after the Polish zoologist who conducted that research, August Dehnel. © 2017 The New York Times Company

Related chapters from BN8e: Chapter 13: Homeostasis: Active Regulation of the Internal Environment; Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment; Chapter 10: Biological Rhythms and Sleep
Link ID: 24236 - Posted: 10.24.2017

By Leslie Kaufman It is 7 p.m. on a spring Friday, and the Highland Hospital emergency room in Oakland, one of the busiest trauma centers in northern California, is expecting. When the patient—a young bicyclist hit by a car—arrives, blood is streaming down his temples. From a warren of care rooms, a team of nearly a dozen doctors and nurses materializes and buzzes around the patient. Amelia Breyre, a first-year resident who looks not much older than a college sophomore, immediately takes charge. As soon as the team finishes immobilizing the victim, Breyre must begin making split-second decisions: X-ray? Intubate? Transfusion? She quickly determines there is no internal bleeding or need for surgery and orders up neck X-rays after bandaging the patient’s head. Breyre will make a half-dozen similar critical choices tonight. Highland, a teaching hospital, is perhaps the most selective emergency-medical residency in the nation. To be here, she must be outstanding. To succeed, though, she must stay sharp. That quality of focus—amid the chaos and battered ­humanity that comes through Highland’s doors—is itself in need of urgent care. Andrew Herring, an emergency-room doctor who supervises Breyre and 40 other residents, is worried about the team. ER doctors are shift workers, and their hours are spread over a dizzying, ever-changing schedule of mornings, afternoons, and nights that total 20 ­different shifts a month. That’s meant to equally distribute the burden of nocturnal work across an entire team of physicians. But despite those good intentions, Herring says, the result is that every single one of them is exhausted and sleep ­deprived. That’s dangerous for doctor and patient alike.

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24165 - Posted: 10.09.2017

Allison Aubrey "With exquisite precision, our inner clock adapts our physiology to the dramatically different phases of the day," the Nobel Prize committee wrote of the work of Jeffrey C. Hall, Michael Rosbash and Michael W. Young. "The clock regulates critical functions such as behavior, hormone levels, sleep, body temperature and metabolism." We humans are time-keeping machines. And it seems we need regular sleeping and eating schedules to keep all of our clocks in sync. Studies show that if we mess with the body's natural sleep-wake cycle — say, by working an overnight shift, taking a trans-Atlantic flight or staying up all night with a new baby or puppy — we pay the price. Our blood pressure goes up, hunger hormones get thrown off and blood sugar control goes south. We can all recover from an occasional all-nighter, an episode of jet lag or short-term disruptions. But over time, if living against the clock becomes a way of life, this may set the stage for weight gain and metabolic diseases such as Type 2 diabetes. "What happens is that you get a total de-synchronization of the clocks within us," explains Fred Turek, a circadian scientist at Northwestern University. "Which may be underlying the chronic diseases we face in our society today." So consider what happens, for instance, if we eat late or in the middle of the night. The master clock — which is set by the light-dark cycle — is cuing all other clocks in the body that it's night. Time to rest. "The clock in the brain is sending signals saying: Do not eat, do not eat!" says Turek. But when we override this signal and eat anyway, the clock in the pancreas, for instance, has to start releasing insulin to deal with the meal. And, research suggests, this late-night munching may start to reset the clock in the organ. The result? Competing time cues. © 2017 npr

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24143 - Posted: 10.04.2017

Tina Hesman Saey Discoveries about the molecular ups and downs of fruit flies’ daily lives have won Jeffrey C. Hall, Michael Rosbash and Michael W. Young the Nobel Prize in physiology or medicine. These three Americans were honored October 2 by the Nobel Assembly at the Karolinska Institute in Stockholm for their work in discovering important gears in the circadian clocks of animals. The trio will equally split the 9 million Swedish kronor prize — each taking home the equivalent of $367,000. The researchers did their work in fruit flies. But “an awful lot of what was subsequently found out in the fruit flies turns out also to be true and of huge relevance to humans,” says John O’Neill, a circadian cell biologist at the MRC Laboratory of Molecular Biology in Cambridge, England. Mammals, humans included, have circadian clocks that work with the same logic and many of the same gears found in fruit flies, say Jennifer Loros and Jay Dunlap, geneticists at the Geisel School of Medicine at Dartmouth College. Circadian clocks are networks of genes and proteins that govern daily rhythms and cycles such as sleep, the release of hormones, the rise and fall of body temperature and blood pressure, as well as other body processes. Circadian rhythms help organisms, including humans, anticipate and adapt to cyclic changes of light, dark and temperature caused by Earth’s rotation. When circadian rhythms are thrown out of whack, jet lag results. Shift workers and people with chronic sleep deprivation experience long-term jet lag that has been linked to serious health consequences including cancer, diabetes, heart disease, obesity and depression. © Society for Science & the Public 2000 - 2017.

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24138 - Posted: 10.03.2017

Bill Chappell Jeffrey C. Hall, Michael Rosbash a and Michael W. Young are the joint winners of the 2017 Nobel Prize in Physiology or Medicine, winning for their discoveries about how internal clocks and biological rhythms govern human life. The three Americans won "for their discoveries of molecular mechanisms controlling the circadian rhythm" the Nobel Foundation says. From the Nobel Assembly at Karolinska Institutet, which announced the prize early Monday morning: "Using fruit flies as a model organism, this year's Nobel laureates isolated a gene that controls the normal daily biological rhythm. They showed that this gene encodes a protein that accumulates in the cell during the night, and is then degraded during the day. Subsequently, they identified additional protein components of this machinery, exposing the mechanism governing the self-sustaining clockwork inside the cell. We now recognize that biological clocks function by the same principles in cells of other multicellular organisms, including humans. "With exquisite precision, our inner clock adapts our physiology to the dramatically different phases of the day. The clock regulates critical functions such as behavior, hormone levels, sleep, body temperature and metabolism." Hall, 72, was born in New York and has worked at institutions from the University of Washington to the California Institute of Technology. For decades, he was on the faculty at Brandeis University in Waltham, west of Boston; more recently, he has been associated with the University of Maine. Rosbash, 73, was born in Kansas City, Mo., and studied at the Massachusetts Institute of Technology and at the University of Edinburgh in Scotland. Since 1974, he has been on faculty at Brandeis University in Waltham, Mass. Young, 68, was born in Miami, Fla., and earned his doctoral degree at the University of Texas in Austin. He then worked as a postdoctoral fellow at Stanford University in Palo Alto before joining the faculty at the Rockefeller University in 1978. © 2017 npr

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 24136 - Posted: 10.02.2017

Aaron E. Carroll Many high-school-aged children across the United States now find themselves waking up much earlier than they’d prefer as they return to school. They set their alarms, and their parents force them out of bed in the morning, convinced that this is a necessary part of youth and good preparation for the rest of their lives. It’s not. It’s arbitrary, forced on them against their nature, and a poor economic decision as well. The National Heart, Lung and Blood Institute recommends that teenagers get between nine and 10 hours of sleep. Most in the United States don’t. It’s not their fault. My oldest child, Jacob, is in 10th grade. He plays on the junior varsity tennis team, but his life isn’t consumed by too many extracurricular activities. He’s a hard worker, and he spends a fair amount of time each evening doing homework. I think most nights he’s probably asleep by 10 or 10:30. His school bus picks him up at 6:40 a.m. To catch it, he needs to wake up not long after 6. Nine hours of sleep is a pipe dream, let alone 10. There’s an argument to be made that we should cut back on his activities or make him go to bed earlier so that he gets more sleep. Teens aren’t wired for that, though. They want to go to bed later and sleep later. It’s not the activities that prevent them from getting enough sleep — it’s the school start times that require them to wake up so early. More than 90 percent of high schools and more than 80 percent of middle schools start before 8:30 a.m. Some argue that delaying school start times would just cause teenagers to stay up later. Research doesn’t support that idea. A systematic review published a year ago examined how school start delays affect students’ sleep and other outcomes. Six studies, two of which were randomized controlled trials, showed that delaying the start of school from 25 to 60 minutes corresponded with increased sleep time of 25 to 77 minutes per week night. In other words, when students were allowed to sleep later in the morning, they still went to bed at the same time, and got more sleep. © 2017 The New York Times Company

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 13: Memory, Learning, and Development
Link ID: 24060 - Posted: 09.13.2017

Thomas Cronin We humans are uncommonly visual creatures. And those of us endowed with normal sight are used to thinking of our eyes as vital to how we experience the world. Vision is an advanced form of photoreception – that is, light sensing. But we also experience other more rudimentary forms of photoreception in our daily lives. We all know, for instance, the delight of perceiving the warm sun on our skin, in this case using heat as a substitute for light. No eyes or even special photoreceptor cells are necessary. But scientists have discovered in recent decades that many animals – including human beings – do have specialized light-detecting molecules in unexpected places, outside of the eyes. These “extraocular photoreceptors” are usually found in the central nervous system or in the skin, but also frequently in internal organs. What are light-sensing molecules doing in places beyond the eyes? Vision depends on detecting light All the visual cells identified in animals detect light using a single family of proteins, called the opsins. These proteins grab a light-sensitive molecule – derived from vitamin A – that changes its structure when exposed to light. The opsin in turn changes its own shape and turns on signaling pathways in photoreceptor cells that ultimately send a message to the brain that light has been detected. © 2010–2017, The Conversation US, Inc.

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 7: Vision: From Eye to Brain
Link ID: 23947 - Posted: 08.11.2017

By Linda Geddes BILLIONS of dollars have been spent in search of treatments for psychiatric conditions and brain disorders, when a cheap and effective drug may have been right under our noses: light. Now hospitals are turning to light to treat depression, strokes and Parkinson’s disease, using it to hit the reset button on our internal clocks. From green light soothing the pain of migraine, to blue light reducing organ damage during surgery, recent small studies have uncovered some intriguing effects of this therapy. But apart from easing seasonal affective disorder, we’ve been slow to embrace light as a serious contender for treating neurological conditions. We’ve known for 15 years that a special kind of receptor in our eyes transmits information directly to the body’s master clock, as well as other brain areas that control mood and alertness. These cells are particularly responsive to bluish light, including sunlight. These receptors enable light to act as a powerful reset switch, keeping the clock in our brain synced to the outside world. But this clock can fall out of sync or weaken as part of ageing or a range of disorders – a problem doctors are now starting to treat with light. Most hospitals have small windows and 24-hour lighting, both of which might exacerbate health problems. To tackle this, several hospitals in Europe and the US are installing dynamic “solid state” lighting, which changes like daylight over the course of a day. Such lights can, for example, shine bright whitish-blue in the morning, grow warmer and dimmer throughout the day, and turn orange or switch off at night. © Copyright New Scientist Ltd.

Related chapters from BN8e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 23808 - Posted: 07.06.2017