Meghan Rosen The people of Flint, Mich., are drinking bottled water now, if they can get it. Volunteers deliver it door-to-door and to local fire stations. The goal is to keep the city’s residents from ingesting so much lead. Success – or lack thereof – could have consequences not just now, but for generations to come. Late last year, scientists raised alarms over a link between the city’s lead-tainted water and the growing number of children with high lead levels in their blood. It’s a serious problem. Lead is toxic to the brain, something scientists have long known. “Lead is probably the most well-known neurotoxin to man,” says Mona Hanna-Attisha, the pediatrician who first connected lead in Flint’s water to lead exposure in kids. And as scientists are beginning to find out, the damage that lead inflicts on children may be long-lasting. In addition to harming kids during youth, lead could contribute to disorders that develop later in life, such as Alzheimer’s disease or schizophrenia. Lead’s reach could extend even further, too — beyond those who drank the contaminated water to their children and grandchildren. Flint’s kids “will have to be followed throughout their whole life, and maybe into the next generation or two,” says Douglas Ruden, a neural toxicologist at Wayne State University in Detroit. A few months of drinking clean water will help bring the kids’ lead levels back down, he says. “But the damage is done.” And it’s permanent. In the United States, lead is everywhere. Decades of burning leaded gasoline spewed lead into the air, and the element settled in the upper layer of soil, clinging to particles of dirt. © Society for Science & the Public 2000 - 2016.

Keyword: Development of the Brain; Neurotoxins
Link ID: 21901 - Posted: 02.16.2016

By BENEDICT CAREY Over the past few decades, cognitive scientists have found that small alterations in how people study can accelerate and deepen learning, improving retention and comprehension in a range of subjects, including math, science and foreign languages. The findings come almost entirely from controlled laboratory experiments of individual students, but they are reliable enough that software developers, government-backed researchers and various other innovators are racing to bring them to classrooms, boardrooms, academies — every real-world constituency, it seems, except one that could benefit most: people with learning disabilities. Now, two new studies explore the effectiveness of one common cognitive science technique — the so-called testing effect — for people with attention-deficit problems, one of the most commonly diagnosed learning disabilities. The results were mixed. They hint at the promise of outfoxing learning deficits with cognitive science, experts said, but they also point to the difficulties involved. The learning techniques developed by cognitive psychologists seem, in some respects, an easy fit for people with attention deficits: breaking up study time into chunks, mixing related material in a session, varying study environments. Each can produce improvements in retention or comprehension, and taken together capture the more scattered spirit of those with attention deficit hyperactivity disorder, especially children. The testing effect has proved especially reliable for other students, and it is a natural first choice to measure the potential application to A.D.H.D. The principle is straightforward: Once a student is familiar with a topic, testing himself on it deepens the recall of the material more efficiently than restudying. © 2016 The New York Times Company

Keyword: ADHD; Learning & Memory
Link ID: 21900 - Posted: 02.16.2016

By Nancy Szokan It’s well known that physical activity is a mood elevator. But writing in “The Athlete’s Way” blog on Psychology Today’s website, endurance athlete Christopher Bergland discusses a study indicating that combining movement with the attention-focusing benefits of meditation can be an extra-effective tool in fighting depression. The small study, conducted at Rutgers University in New Jersey, was based on a set of assumptions: Healthy brains are constantly producing neurons. Brains of people under stress or suffering depression produce fewer neurons. Physical activity increases neuron production, as do antidepressant medications. (Meanwhile, a certain number of newborn neurons die off.) Mental exercise — “effortful learning,” which requires focus — reduces those deaths. People with depression often have problems with focus. The researchers tested a novel intervention — it’s called MAP because it involves mental and physical training — aimed at both increasing neuron production and keeping those neurons alive. Fifty-two people completed the study — 22 with major depressive disorder, or MDD, and 30 who were not depressed. Twice a week, they performed 30 minutes of meditation during which they were directed to constantly focus on their breathing; they began each session seated, but for the last 10 minutes they meditated while walking slowly. Then they performed 30 minutes of moderate physical activity on a treadmill or stationary cycle. After eight weeks, the researchers found that the MDD patients’ depressive symptoms had been reduced by 40 percent. (The non-depressed participants also said they felt happier.)

Keyword: Depression
Link ID: 21899 - Posted: 02.16.2016

By SINDYA N. BHANOO The human brain is attracted to things that were once pleasing even if they no longer are, researchers report. Study participants were asked to find red and green objects on a computer screen filled with different colored objects. They received small rewards for finding the objects: $1.50 for the red ones and 25 cents for the green ones. The next day, while brain scans were conducted, participants were asked to find certain shapes on the screen. There was no reward, and color was irrelevant. Still, when a red object appeared, participants focused on it, and scans showed dopamine was released in their brains. “They are not getting a reward for that, yet part of the brain is saying, ‘Oh, there’s a reward — pay attention to it,’” said Susan M. Courtney, a cognitive neuroscientist at Johns Hopkins University and a co-author of the study in Current Biology. The findings may help researchers develop pharmaceutical treatments for problems like food or drug addiction. © 2016 The New York Times Company

Keyword: Drug Abuse; Learning & Memory
Link ID: 21898 - Posted: 02.16.2016

By Dominic Howell BBC News A new therapy which involves a patient embodying themselves in a virtual reality avatar of a crying child could help with depression, research has suggested. Patients wear a headset that projects a life-sized image, firstly of an adult and then of a child. The new research tested the technology for the first time on patients with a mental health problem. The project is part of a continuing study at University College London. The university, which is working in collaboration with ICREA-University of Barcelona, has suspected for several years that virtual therapy could help with mental health conditions. This latest research - which has been published in the British Journal of Psychiatry Open and was funded by the Medical Research Council - lays the basis for a large-scale clinical trial to be carried out in the future. The study took 15 people who were all being treated by the NHS for depression and put them through the avatar experience. Firstly, the patients - 10 of whom were female and the rest male - put on a headset which projected an adult version of themselves into a virtual reality mirror. The patient was asked to mentally identify with the adult avatar, which exactly replicated the patient's body movements, in a process known as "embodiment". They then noticed a separate avatar of a small crying child, who was also in the mirror. They were told to say compassionate phrases to the child to try and comfort and console it. Patients asked the child to think of a time when it was happy, and to think of someone who loved them. At this stage of the experiment the roles were then reversed. © 2016 BBC

Keyword: Depression
Link ID: 21897 - Posted: 02.15.2016

By Lindsey Tanner CHICAGO — Two blood-building drugs injected soon after birth may give premature babies a lasting long-term edge, boosting brain development and IQ by age 4, a first-of-its-kind study found. The study was small but the implications are big if larger, longer studies prove the drugs help level the playing field for these at-risk newborns, the researchers and other experts say. Preemies who received the medicines scored much better by age 4 on measures of intelligence, language and memory than those who did not. The medicine-receiving group’s scores on an important behavior measure were just as high as a control group of 4-year-olds born on time at a normal weight. The results are “super exciting,” said Robin Ohls, the lead author and a pediatrics professor at the University of New Mexico. She said it is the first evidence of long-term benefits of the drugs when compared with no blood-boosting treatment. Although the treated babies didn’t do as well as the normal-weight group on most measures, their scores were impressive and suggest greater brain development than the other preemies, Ohls said. They scored about 12 points higher on average on IQ tests than the untreated infants but about 10 points lower than the normal-weight group. On tests measuring memory and impulsive behavior, the treated babies fared as well as those born at normal weight.

Keyword: Development of the Brain
Link ID: 21896 - Posted: 02.15.2016

Laura Sanders WASHINGTON — Tiny orbs of brain cells swirling in lab dishes may offer scientists a better way to study the complexities of the human brain. Toxicologist Thomas Hartung described these minibrains, grown from stem cells derived from people’s skin cells, at the annual meeting of the American Association for the Advancement of Science. Insights from experiments on animals are often difficult to apply to humans, Hartung, of Johns Hopkins University, said in a news briefing February 12. “We need something else,” he said. “We are not 150-pound rats.” These minibrains aren’t flashy. Other minibrain systems created by scientists in the past have complex neural structures and elaborate development (SN: 9/21/13, p. 5), representing the Ferraris and Maseratis of minibrains, Hartung said. In contrast, he said, his minibrains are Mini Coopers. But these bare-bones models, made of busy nerve cells and support cells in a sphere about the size of a fly eye, offer a standardized system that can reliably test the effects of a wide range of drugs. Hartung and colleagues are developing a company to make minibrains quickly available to researchers who could use them to study such disorders as autism, depression and Alzheimer’s disease, he said. The minibrains would cost about as much as a lab rat. © Society for Science & the Public 2000 - 2016

Keyword: Development of the Brain
Link ID: 21895 - Posted: 02.15.2016

By Ann Gibbons Depressed? Your inner Neandertal may be to blame. Modern humans met and mated with these archaic people in Europe or Asia about 50,000 years ago, and researchers have long suspected that genes picked up in these trysts might be shaping health and well-being today. Now, a study in the current issue of Science details their impact. It uses a powerful new method for scanning the electronic health records of 28,000 Americans to show that some Neandertal gene variants today can raise the risk of depression, skin lesions, blood clots, and other disorders. Neandertal genes aren’t all bad. “These variants sometimes protect against a disease, sometimes make people more susceptible to disease,” says paleogeneticist Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. Two other new studies identified three archaic genes that boost immune response. And most archaic genes that persist in humans were likely beneficial in prehistoric times. But some now cause disease because modern lifestyles and environments are so different. Living people carry only trace amounts of Neandertal DNA, which makes its impact on health more striking. “The Neandertal genetic contribution to present-day people seems to have larger physiological effects than I would have naïvely thought,” says Pääbo, who helped launch this avenue of research by sequencing the first ancient genomes but was not involved in these studies. On average, Europeans and Asians have inherited about 1.5% of their genomes from Neandertals. Island Melanesians carry an additional 2% to 3% of DNA inherited from another extinct group, the Denisovans. Most Africans lack this archaic DNA because the interbreeding happened after modern humans left Africa. © 2016 American Association for the Advancement of Science

Keyword: Depression; Genes & Behavior
Link ID: 21894 - Posted: 02.13.2016

Mo Costandi Tell me where dwell the thoughts, forgotten till thou call them forth? Tell me where dwell the joys of old, and where the ancient loves, And when will they renew again, and the night of oblivion past, That I might traverse times and spaces far remote, and bring Comforts into a present sorrow and a night of pain? Where goest thou, O thought? To what remote land is thy flight? If thou returnest to the present moment of affliction, Wilt thou bring comforts on thy wings, and dews and honey and balm, Or poison from the desert wilds, from the eyes of the envier? In his epic poem, Visions of the Daughters of Albion, William Blake wonders about the nature of memory, its ability to mentally transport us to distant times and places, and the powerful emotions, both positive and negative, that our recollections can evoke. The poem contains questions that remain highly pertinent today, such as what happens to our long-lost memories, and how do we retrieve them? More than two centuries later, the mechanisms of memory storage and retrieval are the most intensively studied phenomena in the brain sciences. It’s widely believed that memory formation involves the strengthening of connections between sparsely distributed networks of neurons in a brain structure called the hippocampus, and that subsequent retrieval involves reactivation of the same neuronal ensembles. And yet, neuroscientists still struggle to answer Blake’s questions definitely. Now, a team of researchers at the University of Geneva have made another important advance in our understanding of the neural mechanisms underlying memory formation. Using a state-of-the-art method called optogenetics, they show how the neuronal ensembles that encode memories emerge, revealing that ensembles containing too many neurons – or too few – impair memory retrieval. © 2016 Guardian News and Media Limited

Keyword: Learning & Memory
Link ID: 21893 - Posted: 02.13.2016

Sara Reardon Mice are sensitive to minor changes in food, bedding and light exposure. It’s no secret that therapies that look promising in mice rarely work in people. But too often, experimental treatments that succeed in one mouse population do not even work in other mice, suggesting that many rodent studies may be flawed from the start. “We say mice are simpler, but I think the problem is deeper than that,” says Caroline Zeiss, a veterinary neuropathologist at Yale University in New Haven, Connecticut. Researchers rarely report on subtle environmental factors such as their mice’s food, bedding or exposure to light; as a result, conditions vary widely across labs despite an enormous body of research showing that these factors can significantly affect the animals’ biology. “It’s sort of surprising how many people are surprised by the extent of the variation” between mice that receive different care, says Cory Brayton, a pathologist at Johns Hopkins University in Baltimore, Maryland. At a meeting on mouse models at the Wellcome Genome Campus in Hinxton, UK, on 9–11 February, she and others explored the many biological factors that prevent mouse studies from being reproduced. Christopher Colwell, a neuroscientist at the University of California, Los Angeles, has first-hand experience with these issues. He and a colleague studied autism in the same genetically modified mouse line, but obtained different results on the same behaviour tests. Eventually they worked out why: Colwell, who studies circadian rhythms, keeps his mice dark in the daytime to trick their body clocks into thinking day is night, so that the nocturnal animals are more alert when tested during the day. His colleague does not. © 2016 Nature Publishing Group

Keyword: Animal Rights; Miscellaneous
Link ID: 21892 - Posted: 02.13.2016

By Uri Bram Early-life exposure to pathogenic bacteria can induce a lifelong imprinted olfactory memory in C. elegans through two distinct neural circuits, according to a study published today (February 11) in Cell. Researchers from Rockefeller University in New York City have shown that early-life pathogen exposure leads the nematode to have a lifelong aversion to the specific associated bacterial odors, whereas later-in-life exposure spurs only transient aversion. “This study is very exciting,” said Yun Zhang of Harvard who studies learning in C. elegans but was not involved in the present work. “Imprinting is a form of learning widely observed in many animals [but] finding this in C. elegans is very meaningful because this nematode is genetically tractable, and its small nervous system is well described.” A classic example of imprinting is how geese form attachments to the first moving object they see after birth; Nobel laureate Konrad Lorenz famously showed that the “moving object” could be himself instead of a mother goose. During the critical period at the start of life, animals often have unusual abilities to create and maintain long-term memories. For the present study, Rockefeller’s Xin Jin and colleagues described a form of aversive imprinting in their C. elegans: newly hatched nematodes exposed to Pseudomonas aeruginosa PA14 or toxin-emitting Escherichia coli BL21 established a long-term olfactory aversion to it. Animals that experienced the pathogen immediately after hatching were able to synthesize and maintain the aversive memory for the whole of their four-day lifespans, while animals trained in adulthood only retained the aversive memory for up to 24 hours. © 1986-2016 The Scientist

Keyword: Learning & Memory; Development of the Brain
Link ID: 21891 - Posted: 02.13.2016

Alan Yuhas in Washington DC Scientists working on genetically modified worms have made what they hope are the first steps towards developing a preventative treatment for Alzheimer’s disease. The study, published in the journal Science Advances and presented at the American Association for the Advancement of Science conference, describes how researchers modified nematode worms to develop Alzheimer’s-like symptoms, and then applied the existing anti-cancer drug, bexarotene, at various stages of the disease. “We showed that these worms that were doomed to develop Alzheimer’s disease could be rescued,” said study author Michele Vendruscolo, of the University of Cambridge. “It is a powerful first step,” he said. “It is very exciting, but at the same time we are very aware it the first step and many things can go wrong.” Researchers believe that Alzheimer’s destroys brain function through a catastrophic cascade of events: natural proteins start folding and glomming onto each other in dysfunctional ways, a process that in turn creates the toxic molecules thought to kill brain cells. When the proteins started malfunctioning in the worms, the drug could do nothing to save them. But if administered before symptoms developed, it prevented the first stage of the process. © 2016 Guardian News and Media Limited

Keyword: Alzheimers; Genes & Behavior
Link ID: 21890 - Posted: 02.13.2016

Janet Raloff WASHINGTON ― Many people have turned to electronic cigarettes in hopes of avoiding the heart and cancer risks associated with smoking conventional tobacco products. But vaping appears far from benign, a trio of toxicologists reported February 11 and 12 at the American Association for the Advancement of Science annual meeting. If used as a means to totally wean people off of tobacco products, then e-cigarettes might have value, concedes Ilona Jaspers of the University of North Carolina at Chapel Hill. But she’s not sure. Unpublished data that she and the others presented at the meeting link e-cig products to a host of new risks. So vaping may not eliminate risks associated with conventional smoking, Jaspers maintains ― “and may actually be introducing new ones.” Her group examined scraped cells from the noses of otherwise healthy people who had a history of smoking, vaping or doing neither. The researchers then measured the activity levels in these cells of 594 genes associated with the body’s ability to fight infections. Among smokers, the activity of 53 genes was substantially diminished, compared with people who neither smoked nor vaped. Among vapers, those same 53 genes showed significantly diminished activity, Jaspers reported, as did 305 more. The normal role of these genes would suggest that the lung tissue as well as nasal tissue of smokers ― and especially vapers ―“may be more susceptible to any kind of infection.” © Society for Science & the Public 2000 - 2016.

Keyword: Drug Abuse
Link ID: 21889 - Posted: 02.13.2016

By Julia Shaw The approach to Valentine's Day is a reminder that we humans are so intrigued by the idea of love that we have made it into something to celebrate in it’s own right. Love is something amazing. Love is something special. But what are the implications of love for our memories? Remember those “your brain on drugs” awareness posters? You can essentially substitute “love” for “drugs” and the same warnings apply. Scientists have found that being in love actually makes you activate some of the same brain regions as when you take addictive drugs, like ecstasy or cocaine. Neuroscientist Kayo Takahashi and his team have described passionate love as an “all-encompassing experience” which has “disorienting effects” and is generally considered “highly pleasurable”. While you probably don’t need a bunch of scientists to tell you that, you probably do need them to explain what that actually means in the brain. In 2015 Kayo and his team were keen on exploring the role of one particular culprit of the feel-good effects of love, the neurotransmitter dopamine. Among many other effects, dopamine generally makes us feel pleasure. Kayo and his team looked into the brains of people who were in the early stages of romantic relationships, and they found that when shown pictures of their romantic partners, participants experienced a flood of dopamine to parts of their brains. As it turns out, brains need to release dopamine in order to store long-term memories. © 2016 Scientific American

Keyword: Sexual Behavior; Learning & Memory
Link ID: 21888 - Posted: 02.11.2016

By PAM BELLUCK The risk of developing dementia is decreasing for people with at least a high school education, according to an important new study that suggests that changes in lifestyle and improvements in physical health can help prevent or delay cognitive decline. The study, published Wednesday in The New England Journal of Medicine, provides the strongest evidence to date that a more educated population and better cardiovascular health are contributing to a decline in new dementia cases over time, or at least helping more people stave off dementia for longer. The findings have implications for health policy and research funding, and they suggest that the long-term cost of dementia care may not be as devastatingly expensive as policy makers had predicted, because more people will be able to live independently longer. There are wild cards that could dampen some of the optimism. The study participants were largely white and suburban, so results may not apply to all races and ethnicities. Still, a recent study showed a similar trend among African-Americans in Indianapolis, finding that new cases of dementia declined from 1992 to 2001. The 2001 participants had more education, and although they had more cardiovascular problems than the 1992 participants, those problems were receiving more medical treatment. Another question mark is whether obesity and diabetes, which increase dementia risk, will cause a surge in dementia cases when the large number of overweight or diabetic 40- and 50-year-olds become old enough to develop dementia. © 2016 The New York Times Company

Keyword: Alzheimers; Learning & Memory
Link ID: 21887 - Posted: 02.11.2016

By Sheena Goodyear, A brain implant the size of a paper-clip might one day help paralyzed people regain the ability to use their arms and legs via a wireless connection that will transmit their thoughts to an exoskeleton. It's not the first technology to allow paralyzed people to operate mechanical limbs with signals from their brain, but it has the potential to revolutionize the field because it's minimally invasive and totally wireless. It's made possible because of a matchstick-sized implant called a stentrode, crafted from nitinol, an alloy that is commonly used in brassiere underwires and eyeglass frames, according to a study published in the journal Nature Biotechnology. ​"It's really a new method for getting brain data out of the brain without performing brain surgery," Thomas Oxley, a neurologist at the University of Melbourne who designed the device, told CBC News. "Part of the reason that brain-machine interfaces have not been successful to this point is because they get rejected by the body, and the reason they get rejected is because they all require direct implantation into the brain. And to do that you have to take off the skull — you have to perform a craniotomy." ©2016 CBC/Radio-Canada.

Keyword: Robotics
Link ID: 21886 - Posted: 02.11.2016

Rae Ellen Bichell There's been a male tilt to biomedical research for a long time. The National Institutes of Health is trying to change that and is looking to bring gender balance all the way down to the earliest stages of research. As a condition of NIH funding, researchers will now have to include female and male animals in their biomedical studies. As late as the 1990s, researchers worried that testing drugs in women who could be pregnant or become pregnant might lead to birth defects, so experimental drugs were mainly tested in men. Research in animals followed the same pattern. "There was not the understanding that it really isn't scientifically appropriate to study men and apply your findings to women. We just didn't know that back then," says Dr. Janine Clayton, director of the Office of Research on Women's Health at the NIH. When the drugs this way finally went to market and women took them, sometimes things went wrong. To try to fix the problem, the NIH and Congress required that women and men be included in research involving human subjects. Now, there are more women than men participating in clinical trials, at least in studies funded by the NIH. But there's still a mystery: Why do women still report many more bad reactions to medications than men do? "Men and women respond to medications differently. In fact, one study looked at the drugs that have been taken off the market and 8 of the 10 drugs taken off the market in that particular time period had more severe effects in women," says Clayton. © 2016 npr

Keyword: Sexual Behavior
Link ID: 21885 - Posted: 02.11.2016

Jo Marchant The brain cells of people with Parkinson’s disease can be trained to reliably respond to placebo drugs, Italian neuroscientists report. The training wears off after 24 hours but the effect shows it may be possible to reduce the medication needed to treat Parkinson’s by interspersing real drugs with inert injections or pills, says placebo researcher Fabrizio Benedetti at the University of Turin, Italy, who led the work. A few people with Parkinson’s disease do respond dramatically to placebos, but most do not1. People with the condition suffer characteristic tremors and stiff muscles because their dopamine-producing brain cells are gradually dying off. They alleviate their symptoms by taking drugs such as apomorphine, which activate receptors for dopamine. For some conditions — such as pain and immune disorders — trials have shown2 that it is possible to train people to respond to placebos, although this practice hasn’t made its way into clinical care. Benedetti and his colleagues wondered whether the same effect might be possible for neurological disorders. They studied 42 people with advanced Parkinson’s disease who were having electrodes implanted into their brains for a therapy called deep brain stimulation, which eases symptoms by stimulating affected brain areas directly. That surgery gave Benedetti’s team a rare opportunity to measure the activity of individual neurons in the thalamus, a brain region known to be inhibited by lack of dopamine in people with Parkinson's. © 2016 Nature Publishing Grou

Keyword: Parkinsons
Link ID: 21884 - Posted: 02.10.2016

By CARL ZIMMER The Zika virus has quickly gained Ebola-level notoriety as it has spread through the Western Hemisphere in recent months. Researchers in Brazil, where it was first detected in May, have linked infections in pregnant women to a condition known as microcephaly: infants born with undersize heads. Where birth defects are concerned, however, the Zika virus is far from unique. A number of other viruses, such as rubella and cytomegalovirus, pose a serious risk during pregnancy. Researchers have uncovered some important clues about how those pathogens injure fetuses — findings that are now helping to guide research into the potential link between Zika and microcephaly. “I think we’ll discover a lot of parallels,” said Dr. Mark R. Schleiss, the director of pediatric infectious diseases and immunology at the University of Minnesota Medical School. The risk that viruses pose during pregnancy came to light in the mid-1900s, when outbreaks of rubella, or German measles, led to waves of birth defects, including microcephaly, cataracts and deformed hearts and livers. The number of infants affected was staggering. In an epidemic in Philadelphia in 1965, 1 percent of all babies were born with congenital rubella syndrome, which can also cause deafness, developmental disability, low birth weight and seizures. Because of vaccinations, such devastation is now rare in the United States and a number of other countries. “I’m 52, and I’ve seen one case of congenital rubella syndrome,” said Dr. David W. Kimberlin, a professor of pediatrics at the University of Alabama at Birmingham. But the virus is still a grave threat in developing countries. Worldwide, more than 100,000 children are born each year with congenital rubella syndrome. © 2016 The New York Times Company

Keyword: Development of the Brain
Link ID: 21883 - Posted: 02.10.2016

By Jordana Cepelewicz Seasonal variations play a major role in the animal kingdom—in reproduction, food availability, hibernation, even fur color. Whether this seasonality has such a significant influence on humans, however, is an open question. Its best-known association is with mood—that is, feeling down during the colder months and up in the summer—and, in extreme cases, seasonal depression, a phenomenon known as seasonal affective disorder (SAD). A new study published in this week’s Proceedings of the National Academy of Sciences seeks to delve deeper into how human biology has adapted not only to day/night cycles (circadian rhythms) but to yearly seasonal patterns as well. Scientists have previously found seasonal variation in the levels and concentrations of certain compounds associated with mood (including dopamine and serotonin), conception and even mortality. Now for the first time, using functional MRI, “it’s [been] conclusively shown that cognition and the brain’s means of cognition are seasonal,” says neuroscientist Gilles Vandewalle of the University of Liège in Belgium, the study’s lead researcher. These findings come at a time when some scientists are disputing the links between seasonality and mental health. Originally aiming to investigate the impact of sleep and sleep deprivation on brain function, Vandewalle and his fellow researchers placed 28 participants on a controlled sleep/wake schedule for three weeks before bringing them into the laboratory, where they stayed for 4.5 days. During this time they underwent a cycle of sleep deprivation and recovery in the absence of seasonal cues such as natural light, time information and social interaction. Vandewalle’s team repeated the entire procedure with the same subjects several times throughout the course of nearly a year and a half. © 2016 Scientific American

Keyword: Attention; Biological Rhythms
Link ID: 21882 - Posted: 02.10.2016