By Nicholas Bakalar Getting enough sleep is healthful, but getting too much might not be. Researchers gathered health and lifestyle information, including self-reported sleep data, on 116,632 people in 21 countries. Over eight years of follow-up, they recorded 4,381 deaths and 4,365 major cardiovascular events. The study, in the European Heart Journal, found that compared with people who slept six to eight hours a night, those who slept eight to nine hours had a 5 percent increased risk for cardiovascular disease or death. People who slept nine to 10 hours had a 17 percent increased risk, and those who slept more than 10 hours increased their risk by 41 percent. The researchers also found a 9 percent increased risk in people who slept less than six hours, but that difference was not statistically significant. Daytime naps also increased the risk for cardiovascular events, but only in people who slept more than six hours a night. The researchers controlled for age, body mass index, physical activity, diabetes, depression, smoking, alcohol consumption and many other health and behavioral characteristics. “Get enough sleep — that is, six to eight hours a day,” said the lead author, Chuangshi Wang, a doctoral student at McMaster University in Hamilton, Ontario. “But if you sleep more than nine hours a day, you may want to visit a doctor to check your overall health.” © 2018 The New York Times Company

Keyword: Sleep
Link ID: 25750 - Posted: 12.06.2018

By Pam Belluck CHARLOTTE, N.C. — Steve Singer, who has bipolar and borderline personality disorders, knows when he’s on the verge of a mental health crisis. The female voice he hears incessantly in his head suddenly shuts up, and the hula hoop he gyrates while walking to the grocery store stops easing his anxieties. That’s when he gets to a hospital. Usually, talking briefly with a nurse or social worker calms him enough to return home. But this year a hospital placed him on a locked ward, took his phone, and had an armed guard watch him for 20 hours before a social worker spoke with him and released him. “I get the heebie-jeebies thinking about it,” said Mr. Singer, 60. “They didn’t help me, they hurt me.” Deeply upset, he turned to something he’d never known existed: He completed a psychiatric advance directive, a legal document declaring what treatment he does and doesn’t want. Increasingly, patients, advocates and doctors believe such directives (called PADs) could help transform the mental health system by allowing patients to shape their care even when they lose touch with reality. Hospitals must put them in patients’ medical records and doctors are expected to follow them unless they document that specific preferences aren’t in the patients’ best medical interest. As the pendulum has swung from institutionalization to outpatient care, psychiatric directives also offer a middle path by allowing patients to designate family members to speak for them when they’re too sick to do so themselves. But some doctors and hospitals are wary that the documents could tie their hands and discourage treatment they consider warranted. Some worry the directives won’t be updated to reflect medical advances. Others question whether people with serious psychiatric conditions are ever capable of lucidly completing such directives. “A decision based on erroneous information on a PAD, that can happen,” said Dr. Katayoun Tabrizi, a forensic psychiatrist at Duke. “This is not a cookbook.” © 2018 The New York Times Company

Keyword: Schizophrenia; Alzheimers
Link ID: 25749 - Posted: 12.04.2018

By Philip S. Gutis With a slow moving disease like Alzheimer’s, there’s still time for doubt. Perhaps the diagnosis is wrong and the memory holes and struggle for words are just normal aging. Deep in your psyche, there’s still a little spark of hope. But there comes a moment when denial is no longer an option. Like Alzheimer’s itself, the moment creeps up slowly, taking care to not give away too much too soon. My moment came recently, as I was walking past the Bucks County Playhouse in downtown New Hope, Pa. I correctly remembered that my husband, Tim, and I recently saw a show there. I even remembered who went with us. But I had no recollection of what show I had seen. Tim reminded me that it was “Guys and Dolls,” but the memory wasn’t there. No songs, no story, no scenes. Nothing at all. The next morning, I sat quietly on my bed. “Tim,” I said, “It’s coming, isn’t it?” Without asking what I meant, Tim gently said, “Yes, it’s coming.” I cried, of course, but just a little. I’ve known, obviously, that change is coming. I’ve been tested, prodded, injected and studied for well over two years as part of a clinical trial. But looking back, I realize that I’ve still harbored a shadow of doubt. The shadow is gone. The spark of hope has been extinguished. Now we have to seriously plan for the future. Alzheimer’s will continue to steal from me, and, unless there’s an unlikely medical miracle, nothing is going to stop the creeping loss. Loss of memory. Loss of mobility. Loss of freedom. Despite this, I haven’t thrown in the towel. Deep down, I know there’s much more life to live, much more time to fight and to love. The years since my diagnosis haven’t been all bad. A few months after we learned the news, my partner of 12 years and I went to the county courthouse to get married. My sister and my nieces and nephew joined us and took pictures as we kissed for the first time as a married couple and fulfilled the Jewish tradition of breaking a glass for good luck. © 2018 The New York Times Company

Keyword: Alzheimers
Link ID: 25748 - Posted: 12.04.2018

By Daphna Joel and Cordelia Fine In 17th and 18th century Europe, the rise of egalitarian ideals created the need for a scientific account of women’s inferior status. Thus was born gender biological complementarity — the notion that, as historian of science Londa Schiebinger explains in The Mind Has No Sex, “Women were not to be viewed merely as inferior to men but as fundamentally different from, and thus incomparable to, men.” It has been with us in one way or another, roping in science to explain the gender status quo, ever since. At its core is the persistent belief that men’s and women’s natures can be usefully and meaningfully carved into two categories or “natural kinds,” that are distinct, timeless, and deeply biologically grounded. Today’s version of this idea continues a centuries long quest to find the source of this hypothesized divergence in abilities, preferences, and behavior in the brain: You can find this notion at work, for instance, in popular books like John Gray’s “Men Are from Mars, Women Are from Venus” in the 1990s, Louann Brizendine’s “The Female Brain” and “The Male Brain” the following decade, and last year’s “Results at the Top: Using Gender Intelligence to Create Breakthrough Growth” by Barbara Annis and Richard Nesbitt. But a version of the same assumption is also sometimes subtly present in scientific research. Consider, for example, Cambridge University psychologist Simon Baron-Cohen’s influential Empathizing-Systemizing theory of brains and the accompanying “extreme male brain” theory of autism. This presupposes there is a particular “systemizing” brain type that we could meaningfully describe as “the male brain,” that drives ways of thinking, feeling, and behaving that distinguish the typical boy and man from the typical “empathizing” girl and woman. © 2018 The New York Times Company

Keyword: Sexual Behavior
Link ID: 25747 - Posted: 12.04.2018

By Moises Velasquez-Manoff In May of 2017, Louise decided that her life was just too difficult, so she’d end it. In the previous four years, three siblings and a half-sibling had died, two from disease, one from fire and one from choking. Close friends had moved away. She felt painfully, unbearably alone. It would be the fourth time Louise (I’m using her middle name to protect her privacy), then 68, would attempt suicide, and she was determined to get it right. She wrote a letter with instructions on where to find important documents and who should inherit what. She packed up her jewelry and artwork, addressing each box to particular friends and family members. Then she checked into a motel — homes where people have committed suicide lose value and she didn’t want hers to sell below market — put a plastic sheet on the bed, lay down and swallowed what she figured was an overdose of prescription pills with champagne. A few days later, she woke up in a psychiatric ward in Albuquerque. The motel maid had found her. “I was very upset I had failed,” she told me recently. So she tried to cut her wrists with a bracelet she was wearing — unsuccessfully. The suicide rate has been rising in the United States since the beginning of the century, and is now the 10th leading cause of death, according to the Centers for Disease Control and Prevention. It’s often called a public health crisis. And yet no new classes of drugs have been developed to treat depression (and by extension suicidality) in about 30 years, since the advent of selective serotonin reuptake inhibitors like Prozac. The trend most likely has social causes — lack of access to mental health care, economic stress, loneliness and despair, the opioid epidemic, and the unique difficulties facing small-town America. These are serious problems that need long-term solutions. But in the meantime, the field of psychiatry desperately needs new treatment options for patients who show up with a stomach full of pills. Now, scientists think that they may have found one — an old anesthetic called ketamine that, at low doses, can halt suicidal thoughts almost immediately. © 2018 The New York Times Company

Keyword: Depression; Drug Abuse
Link ID: 25746 - Posted: 12.03.2018

By Sarah Vander Schaaff Nancy Baum Lipsitz remembers the night the pain began. She’d had a glass of white wine with a friend and went to bed with a terrible headache. The next day, she still felt horrible, the beginning of what she called a “rolling tide” of near constant migraines and lower level headaches. For three years she dealt with the symptoms. Sometimes she got tunnel vision, or a visual aura, a warning that a big headache was on the way. Those felt like “someone taking a pick and jabbing it through my nose and eye,” she said. Then there was the vomiting, numbness and sensitivity to light and noise. Her speech slurred. Less severe headaches felt like a “hangover.” She stopped exercising, socializing and overseeing her 15-year-old daughter’s homework, relying instead on her daughter to take care of her, bringing an ice pack, medication or whatever else she needed when a migraine attacked. “Everything you are as a human being gets stripped away,” Lipsitz said of what was ultimately diagnosed as refractory migraine. The one thing she did not give up was her work. As director of anesthesiology at Carnegie Hill Endoscopy in New York, she knew patients and staff depended on her. “I am not going to let a migraine shut me in the bedroom,” she said. She showed up at 6 a.m., no matter the pain. © 1996-2018 The Washington Post

Keyword: Pain & Touch
Link ID: 25745 - Posted: 12.03.2018

By Stephen L. Macknik Sensory information flowing into our brains is inherently ambiguous. We perceive 3D despite having only 2D images on our retinas. It’s an illusion. A sunburn on our face can feel weirdly cool. Illusion. A little perfume smells good but too much is obnoxious. Also an illusion. The brain expends a great deal of effort to disambiguate the meaning of each incoming signal—often using context as a clue—but the neural mechanisms of these abilities remain mysterious. Neuroscientists are a little closer to understanding how to study these mechanisms, thanks to a new study by Kevin Ortego, Michael Pitts, & Enriqueta Canseco-Gonzalez from Pitts's lab at Reed College, presented at the 2018 Society for Neuroscience meeting, on the brain's responses to both visual and language illusions. Illusions are experiences in which the physical reality is different from our perception or expectation. Ambiguous stimuli are important tools to science because the physical reality can legitimately be interpreted in more than one way. Take the classic rabbit-duck illusion, published by the Fliegende Blätter magazine, in Münich, at the end of the 19th century, in which the image can be seen as either a duck or a rabbit. Bistable illusions like these can flip back and forth between competing interpretations, but one cannot see both percepts at the same time. Recent examples of ambiguous illusions show that numerous interpretations are possible. The first place winner of this year's Best Illusion of the Year Contest, created by from Kokichi Sugihara, shows three different ways of perceiving the same object, depending on your specific vantage point. © 2018 Scientific American,

Keyword: Language; Attention
Link ID: 25744 - Posted: 12.03.2018

By Austin Frakt If part of a hospital stay is to recover from a procedure or illness, why is it so hard to get any rest? There is more noise and light than is conducive for sleep. And nurses and others visit frequently to give medications, take vitals, draw blood or perform tests and checkups — in many cases waking patients to do so. Some monitoring is necessary, of course. Medication must be given; some vital signs do need to be checked. And frequent monitoring is warranted for some patients — such as those in intensive care units. But others are best left mostly alone. Yet many hospitals don’t distinguish between the two, disrupting everyone on a predefined schedule. Peter Ubel understands the problem as both a physician and patient. When he spent a night in the hospital recovering from surgery in 2013, he was interrupted multiple times by blood draws, vital sign checks, other lab tests, as well as by the beeping of machines. “Not an hour went by without some kind of disruption,” said Dr. Ubel, a physician with Duke University. “It’s a terrible way to start recovery.” It’s more than annoying — such disruptions can harm patients. Short sleep durations are associated with reduced immune function, delirium, hypertension and mood disorders. Hospital conditions, including sleep disruptions, may contribute to “posthospital syndrome” — the period of vulnerability to a host of health problems after hospitalization that are not related to the reason for that hospitalization. “In addressing a patient’s acute illness, we may inadvertently be causing harm by ignoring the important restorative powers of a healing environment,” said Harlan Krumholz, a Yale University physician who has been calling attention to posthospital syndrome for several years. “The key to a successful recovery after illness may be a less stressful, more supportive, more humane experience during the hospitalization.” © 2018 The New York Times Company

Keyword: Sleep
Link ID: 25743 - Posted: 12.03.2018

Ashley P. Taylor Electrically stimulating the lateral orbitofrontal cortex, a brain area behind the eyes, improves the moods of people with depression, according to a study published yesterday (November 29) in Current Biology. The technique used by the researchers, led by Edward Chang of the University of California, San Francisco, is called deep brain stimulation (DBS), in which surgically implanted electrodes send electrical pulses to particular areas of the brain. The approach is already in use as a treatment for movement disorders such as Parkinson’s disease and tremors. But results on its ability to treat depression have been mixed, as NPR reports. The researchers worked with 25 epilepsy patients who already had electrodes implanted into their brains as part of their treatments. Many of the study participants also had signs of depression as evaluated by mood tests the researchers administered, Science News reports. The investigators tried stimulating many areas of the brain, and they found that jolts to the lateral orbitofrontal cortex made patients with signs of depression—but not others who didn’t have symptoms—feel better right away. “Wow, I feel a lot better. . . . What did you guys do?” study coauthor Kristin Sellers recalls a patient exclaiming after receiving the stimulation, she tells NPR. “Only the people who had symptoms [of depression] to start with improved their mood, which suggests that perhaps the effect of what we’re doing is to normalize activity that starts off abnormal,” adds another coauthor, Vikram Rao.

Keyword: Depression
Link ID: 25742 - Posted: 12.03.2018

By Carl Zimmer To demonstrate how smart an octopus can be, Piero Amodio points to a YouTube video. It shows an octopus pulling two halves of a coconut shell together to hide inside. Later the animal stacks the shells together like nesting bowls — and carts them away. “It suggests the octopus is carrying these tools around because it has some understanding they may be useful in the future,” said Mr. Amodio, a graduate student studying animal intelligence at the University of Cambridge in Britain. But his amazement is mixed with puzzlement. For decades, researchers have studied how certain animals evolved to be intelligent, among them apes, elephants, dolphins and even some birds, such as crows and parrots. But all the scientific theories fail when it comes to cephalopods, a group that includes octopuses, squid and cuttlefish. Despite feats of creativity, they lack some hallmarks of intelligence seen in other species. “It’s an apparent paradox that’s been largely overlooked in the past,” said Mr. Amodio. He and five other experts on animal intelligence explore this paradox in a paper published this month in the journal Trends in Ecology and Evolution. For scientists who study animal behavior, intelligence is not about acing a calculus test or taking a car apart and putting it back together. Intelligence comprises sophisticated cognitive skills that help an animal thrive. That may include the ability to come up with solutions to the problem of finding food, for example, or a knack for planning for some challenge in the future. Intelligent animals don’t rely on fixed responses to survive — they can invent new behaviors on the fly. © 2018 The New York Times Company

Keyword: Intelligence; Evolution
Link ID: 25741 - Posted: 12.01.2018

By Kara Manke A single season of high school football may be enough to cause microscopic changes in the structure of the brain, according to a new study by researchers at UC Berkeley, Duke University and the University of North Carolina at Chapel Hill. A 3D representation of a magnetic resonance imaging scan, showing areas in the front and rear of the brain lit up. Magnetic resonance imaging (MRI) brain scans have revealed that playing a single season of high school football can cause microscopic changes in the grey matter in young players’ brains. These changes are located in the front and rear of the brain, where impacts are most likely to occur, as well as deep inside the brain. The researchers used a new type of magnetic resonance imaging (MRI) to take brain scans of 16 high school players, ages 15 to 17, before and after a season of football. They found significant changes in the structure of the grey matter in the front and rear of the brain, where impacts are most likely to occur, as well as changes to structures deep inside the brain. All participants wore helmets, and none received head impacts severe enough to constitute a concussion. The study, which is the cover story of the November issue of Neurobiology of Disease, is one of the first to look at how impact sports affect the brains of children at this critical age. © 2018 UC Regents

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 25740 - Posted: 12.01.2018

Ashley Westerman A single season playing football might be all it takes to change a young athlete's brain. Those are the preliminary findings of research presented this week in Chicago at the annual meeting of the Radiological Society of North America. Researchers used special MRI methods to look at nerve bundles in the brain in a study of the brains of 26 young male football players, average age 12, before and after one season. Twenty-six more young males who didn't play football also got MRI scans at the same time to be used as a control group. In the youths who played football, the researchers found that nerve fibers in their corpus callosum — the band that connects the two halves of brain — changed over the season, says lead study author Jeongchul Kim, a research associate in the Radiology Informatics and Imaging Laboratory at Wake Forest School of Medicine in Winston-Salem, N.C. "We applied here two different imaging approaches," he says. One analyzed the shape of the nerve fibers and the other focused on the integrity of the nerves. Kim says the researchers found some nerve bundles grew longer and other bundles became shorter, or contracted, after the players' initial MRI scans at the beginning of the season. He says they saw no changes in the integrity of the bundles. The team says these results suggest that repeated blows to the head could lead to changes in the shape of the corpus callosum, which is critical to integrating cognitive, motor and sensory functions between the two hemispheres of the brain, during a critical time for brain development in young people. © 2018 npr

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 25739 - Posted: 12.01.2018

By Neuroskeptic The science story of the past week was the claim from Chinese scientist He Jiankui that he has created gene-edited human babies. Prof. He reports that two twin girls have been born carrying modifications of the gene CCR5, which is intended to protect them against future HIV risk. It’s far from clear yet whether the gene-editing that He described has actually taken place – no data has yet been presented. The very prospect of genetically-modifying human beings has, however, led to widespread concern, with He’s claims being described as “monstrous“, “crazy” and “unethical”. All of which got me wondering: could there ever be a neuroscience experiment which attracted the same level of condemnation? What I’m asking here is whether there are neuroscience advances that would be considered inherently unethical. It would, of course, be possible to carry out any neuroscience experiment in an unethical way, by forcing or tricking people into participation. But are there experiments which would be unethical even if all the participants gave full, informed consent at every stage? Here are a couple of possibilities: Intelligence enhancement: Suppose it were possible to substantially boost human intelligence through some kind of technological means, perhaps a drug, or through brain stimulation. I suspect that many people would see this prospect as an ethical problem, because it would give users a definite advantage over non-users and thus, in effect, force people to use the technology in order to keep up. It would be a similar situation to the problem of doping in sports: if doping were widespread, it would be very difficult for non-dopers to compete.

Keyword: Learning & Memory; Intelligence
Link ID: 25738 - Posted: 12.01.2018

Susan Milius Mom nurses her young for weeks on milk that has four times the protein of a cow’s. Yet this mother’s not a mammal. She’s a jumping spider with eight legs and a taste for fruit flies. We mammals have named ourselves after our mammary glands. Yet other animals, from tsetse flies to pigeons, secrete their own versions of milk for their babies. The newly discovered nursing in Toxeus magnus could be the most mammal-like of all, a research team from China proposes in the Nov. 30 Science. Biologists have recognized T. magnus as a species since 1933, but a small spider’s mothering habit was easy to miss. The spiders hunt beasts such as fruit flies and will retreat to a little nest, perhaps attached to a leaf, to raise a family. Study coauthor Zhanqi Chen of the Chinese Academy of Sciences in Menglunzhen, who studies spider behavior, noticed several T. magnus sharing a nest in 2012 and wondered if the species had some sort of extended parental care. It was another five years before he spotted the nursing behavior, when a spiderling clamped itself against mom’s underside one exciting July night in 2017. With a T. magnus female under a microscope, a gentle finger push on the underside of the abdomen will squeeze a tiny bead of white liquid out of a crease called an epigastric furrow, the researchers say. For the first week or so after eggs hatch, a spider mom leaves milk droplets around the nest for the crawling dots of her young to drink. Then nursing turns more mammalian, with little ones pressing themselves against their mother’s body. |© Society for Science & the Public 2000 - 2018

Keyword: Sexual Behavior; Evolution
Link ID: 25737 - Posted: 11.30.2018

By Diana Kwon For almost a decade, cleaning rituals ruled Kathrine’s life. The middle-aged resident of Bergen, a coastal town in the southern tip of Norway, was consumed by a fear of germs and contamination that led to endless cycles of tidying, vacuuming and washing. “I realized that I was facing a catastrophe,” Kathrine Mydland-aas, now 41, recalls. “I couldn’t help the kids with homework, couldn’t make dinner for them, couldn’t give them hugs. I didn’t do anything but cleaning. I tried to quit, but the rituals always won.” Last year, around nine years after Mydland-aas’s cleaning rituals began, a psychologist diagnosed her with obsessive-compulsive disorder (OCD) and referred her to a clinic at the Haukeland University Hospital in Bergen. There, a team was administering a behavioral therapy for the condition that, to Mydland-aas’s surprise, was only four days long. “I thought, what can they do in four days?” she says. “[But] it changed my life.” Mydland-aas is one of more than 1,200 people who have received the Bergen four-day treatment for OCD, a concentrated form of exposure therapy designed by two Norwegian psychologists, Gerd Kvale and Bjarne Hansen. The four-day protocol has recently gained international attention for its effectiveness and efficiency—last month Time magazine named the pair, who are both currently affiliated with the Haukeland University Hospital and the University of Bergen, as two of this year’s 50 most influential people in healthcare. © 2018 Scientific American

Keyword: OCD - Obsessive Compulsive Disorder; Learning & Memory
Link ID: 25736 - Posted: 11.30.2018

Jon Hamilton There's new evidence that mild pulses of electricity can relieve depression — if they reach the right target in the brain. A study of 25 people with epilepsy found that those who had symptoms of depression felt better almost immediately when doctors electrically stimulated an area of the brain just above the eyes, a team reported Thursday in the journal Current Biology. These people were in the hospital awaiting surgery and had wires inserted into their brains to help doctors locate the source of their seizures. Several of the patients talked about the change they felt when the stimulation of the lateral orbitofrontal cortex began, says Kristin Sellers, an author of the paper and a postdoctoral researcher at the University of California, San Francisco. One person's response was: "Wow, I feel a lot better. ... What did you guys do?" The stimulation only lasted a few minutes. After it stopped, the effect on mood quickly faded. To be sure that the effect was real, the researchers also pretended to stimulate the lateral OFC in the same patients without actually running current through the tiny wires implanted in their brains. In those sham treatments, there was no discernible change. DBS is an approved treatment for tremors, including those associated with Parkinson's disease. But results with depression have been less consistent, and DBS isn't approved for this purpose by the Food and Drug Administration. © 2018 npr

Keyword: Depression
Link ID: 25735 - Posted: 11.30.2018

By Abby Ellin The issue was peanut butter. No matter what form it took — creamy, crunchy, straight from the jar or smeared between two slices of bread — it caused Sunny Gold enormous anxiety. In fact, the gooey spread posed such a threat that during her first few years of recovery from binge eating disorder, between 2006 and 2007, Ms. Gold, 42, a communications specialist in Portland, Ore., couldn’t keep it around the house. It was one of her favorite foods, and she feared she would binge on it. Just knowing it was there, lurking in her cupboard, made her feel “unsafe,” as she put it. And that’s when things got really tricky. Because her boyfriend at the time, John Pavlus, didn’t think twice about peanut butter — or any food, for that matter. When Ms. Gold, the author of “Food: The Good Girl’s Drug,” told him that it would be a casualty of her getting healthy, he was taken aback. “It was a bit uncomfortable for me at first,” Mr. Pavlus, a 40-year-old writer and filmmaker, admitted. He knew that Ms. Gold had grappled with binge eating since she was a teenager, but food was something they’d bonded over. So when she decided that she needed to “cut herself off,” he felt that he was losing something, “less for the practical inconvenience than the unexpected feeling of being subtly disconnected from her,” he said. “It was strange to think of these parts of our shared reality as being so radically — to me — redefined. Is peanut butter literally dangerous now? Does that mean I have to treat it that way too? Will it be like this forever?” Mr. Pavlus’s reaction is echoed by many romantic partners of someone with an eating disorder, many of whom — though certainly not all — are women. Partners often want to help, but simply don’t know how. © 2018 The New York Times Company

Keyword: Anorexia & Bulimia
Link ID: 25734 - Posted: 11.30.2018

By Frankie Schembri Fruit flies might not sing songs, make art, or don traditional garments, but that doesn’t mean they don’t have culture. New evidence suggests female fruit flies (Drosophila melanogaster) can create unique dating customs based on the partners they see other female fruit flies select. Cultural traditions—the traits and behaviors that are handed down across generations and spread through social learning—have been found in the grooming patterns of certain apes and the songs of some whales and birds. But scientists had little proof that smaller creatures such as insects could have culture. So researchers set up a series of experiments in which one “observer” female fruit fly watched a “demonstrator” fly pick between two males that differed only in their color—pink or green. When it was their turn to mate, observers chose the same color of mate more than 80% of the time, compared with random chance, researchers report today in Science. The team also tested how reliably preferences were passed to the next generation by placing 12 observers in the center of a hexagonal container surrounded by six demonstrators who went exclusively for either pink or green males. In the next round of mating, the first observers to mate became the demonstrators. Over the course of 36 trials, the pink or green preference “trickled down” to the eighth generation of flies before they started to choose randomly again. © 2018 American Association for the Advancement of Science

Keyword: Sexual Behavior
Link ID: 25733 - Posted: 11.30.2018

By Roni Caryn Rabin A. A deficiency of vitamin B12 can cause neurological and psychiatric problems that “can progress if left untreated, and can lead to irreversible damage,” said Dr. Donald Hensrud, director of the Mayo Clinic’s Healthy Living Program. Fortunately, it can be reversed fairly easily with vitamin pills or injections. Vitamin B12 is required for proper red blood cell formation, nerve function and DNA synthesis. It is naturally present in fish, meat, eggs and dairy products, as well as some fortified breakfast cereals and nutritional yeast products. Strict vegans who avoid animal products can develop a deficiency of B12 over time if they don’t take a supplement. But two-thirds of cases occur in the elderly, who are susceptible because they may not absorb adequate amounts of B12 from foods but who are not routinely tested, Dr. Hensrud said. Consequences of B12 deficiency can cause a range of symptoms that include fatigue, weakness, constipation, loss of appetite and weight loss. Other symptoms include difficulty maintaining balance, depression, confusion, dementia, poor memory and soreness in the mouth or tongue. B12 deficiency may also result in a form of anemia called megaloblastic anemia, which can also result from a deficiency of folic acid, another B vitamin. If anemia is detected on blood tests, levels of both vitamins should be checked. Neurological symptoms can, however, occur in the absence of anemia. Early treatment is critical to avoid potentially irreversible damage. Older adults are susceptible to B12 deficiency because they may have decreased secretion of hydrochloric acid in the stomach, which makes it difficult to absorb B12. Also vulnerable to B12 deficiency are those with gastrointestinal disorders like celiac disease or Crohn’s disease; those who have had weight loss or other gastrointestinal surgery; and those who use certain acid reflux drugs or the diabetes drug metformin. Individuals with pernicious anemia, which affects up to 2 percent of older adults, are also susceptible. © 2018 The New York Times Company

Keyword: Depression
Link ID: 25732 - Posted: 11.30.2018

By R. Douglas Fields SAN DIEGO—In the textbook explanation for how information is encoded in the brain, neurons fire a rapid burst of electrical signals in response to inputs from the senses or other stimulation. The brain responds to a light turning on in a dark room with the short bursts of nerve impulses, called spikes. Each close grouping of spikes can be compared to a digital bit, the binary off-or-on code used by computers. Neuroscientists have long known, though, about other forms of electrical activity present in the brain. In particular, rhythmic voltage fluctuations in and around neurons—oscillations that occur at the same 60-cycle-per-second frequency as AC current in the U.S.—have caught the field’s attention. These gamma waves encode information by changing a signal’s amplitude, frequency or phase (relative position of one wave to another)—and the rhythmic voltage surges influence the timing of spikes. Heated debate has arisen in recent years as to whether these analog signals, akin to the ones used to broadcast AM or FM radio, may play a role in sorting, filtering and organizing the information flows required for cognitive processes. They may be instrumental in perceiving sensory inputs, focusing attention, making and recalling memories and coupling various cognitive processes into one coherent scene. It is thought that populations of neurons that oscillate at gamma frequencies may unite the neural activity in the same way the violin section of an orchestra is coupled together in time and rhythm with the percussion section to create symphonic music. When gamma waves oscillate in resonance, “you get very rich repertoires of behaviors,” says Wolf Singer, a neuroscientist at the Ernst Strüngmann Institute in Frankfurt, Germany, who researches gamma waves. Just as your car’s dashboard will vibrate in sync with the motor vibrating at a resonant frequency, so too can separate populations of neurons couple in resonance. © 2018 Scientific American

Keyword: Brain imaging
Link ID: 25731 - Posted: 11.29.2018