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By Frankie Schembri Some of the deadliest mass shootings in U.S. history, including lone gunmen killing 26 people at the First Baptist Church in Sutherland Springs, Texas, and 17 students and staff at Marjory Stoneman Douglas High School in Parkland, Florida, have occurred in the past 2 years. These tragedies were preventable, says Garen Wintemute, an emergency medicine physician at the University of California (UC), Davis, Medical Center, and the director of UC Davis’s Violence Prevention Research Program. Wintemute has studied gun violence for more than 30 years and is one of the few researchers to approach the matter as an issue of public health. He has gone undercover at gun shows to document illegal activity and worked with California lawmakers to establish gun policies. Wintemute writes about his solutions to gun violence in an opinion piece published this week in The New England Journal of Medicine. Science chatted with him about the unique factors behind mass shootings and which policy interventions are most effective. This interview has been edited for clarity and length. Q: What does it mean to approach gun violence from a public health perspective? A: Firearm violence has been seen traditionally as a crime problem. But gun violence is one of our leading causes of death and injury, and the implications of this violence are huge in terms of the safety and health of our overall population. So, we treat it as we would any other major health problem. We ask: Where does it come from? How does it get amplified? Who is at risk for developing this problem? Can we learn enough to create a treatment or prevention strategy? © 2018 American Association for the Advancement of Science

Keyword: Aggression
Link ID: 25503 - Posted: 09.28.2018

By Lisa Rein In my first Feldenkrais class, we lay on our backs with eyes closed and drifted our eyeballs left to right and back again. We shifted our heads from side to side as our eyes followed in their sockets. Then we changed it up, moving our eyes in the opposite direction from our heads. This may sound like a simple sequence. It’s deceptively challenging. And it continued for an hour, with sitting variations, eyes alternately open and shut, a brain workout that included tracking our thumbs as our bent arms moved at eye level from left to right and back again. These eye calisthenics were supposed to relieve my years of back pain. Yeah, right, I remember thinking that Sunday morning 18 months ago as I felt an odd exhaustion set in. Slow and subtle was harder than I thought. I fidgeted. My eyes grew tired. How was all of this commotion under my lids supposed to stop my right hip from unnecessary rotation when I walked and unfreeze my left shoulder and neck? I had tried the Feldenkrais Method under some duress. Although there aren’t a lot of good studies, my friend Jon told me it had reduced his lower back pain from excruciating to manageable. Too many chiropractors, osteopaths, yoga classes, trainers, acupuncturists and ibuprofen over 30 years of back pain. They had at best given me only temporary relief — or sometimes more pain. Feldenkrais sounded too nuanced, with its slow and subtle movements that were supposed to retrain how I walked, sat or held myself as I typed a story on my computer. © 1996-2018 The Washington Post

Keyword: Pain & Touch
Link ID: 25502 - Posted: 09.28.2018

By Nicholas Bakalar Consuming caffeine regularly may increase the ability to withstand pain, a small study suggests. Researchers recruited 62 men and women, ages 19 to 77, and had them record their daily caffeine intake from coffee, tea, soda, energy drinks and chocolate. They averaged 170 milligrams of caffeine a day, about the amount in two cups of coffee, although 15 percent of the group consumed more than 400 milligrams a day. The study is in Psychopharmacology. After seven days, they took the volunteers into a laboratory to test their pain tolerance using calibrated devices that gradually increased heat or pressure on a volunteer’s forearm or back. The people pressed a button on a hand-held device first when the sensation became painful, and then again when it became intolerable. The experiment controlled for sex and race, current tobacco use and alcohol consumption, among other variables that could affect pain sensation. Still, they found that the more caffeine consumed, the greater the tolerance for pain. “Diet can actually be a useful intervention for decreasing pain sensitivity,” said the lead author, Burel R. Goodin, an associate professor of psychology at the University of Alabama at Birmingham. “It’s not just caffeine. A study has shown, for example, that a plant-based diet can actually help increase pain tolerance.” © 2018 The New York Times Company

Keyword: Pain & Touch
Link ID: 25501 - Posted: 09.28.2018

By Megan Thielking, Walk into Kalypso Wellness Centers in San Antonio, Texas, and you might be treated with one of five “proprietary blends” of ketamine. They’re not cheap—$495 per infusion—and not covered by insurance, but the company offers a “monthly” membership program to cut costs and advertises discounts for members of the military and first responders. Kalypso promotes ketamine, long used as an anesthetic during surgery and more recently as a club drug, as a treatment for more than two dozen conditions, including depression, chronic pain, and migraines. “Congratulations on resetting your life!!!” it cheerily tells patients on a form they’re handed after an infusion. Starting with just one office 19 months ago, Kalypso has expanded rapidly to meet surging patient demand for ketamine and now oversees two other Texas clinics and offices in North Carolina and New York. It recruits customers through online ads and radio spots, and even by visiting support groups for pain patients, people with depression, first responders, and grieving parents who have lost children. Advertisement “You name it, we’ve done it,” said clinic co-founder and anesthesiologist Dr. Bryan Clifton. An investigation by STAT shows that Kalypso’s sweeping claims are hardly uncommon in the booming ketamine treatment business. Dozens of free-standing clinics have opened across the U.S. in recent years to provide the drug to patients who are desperate for an effective therapy and hopeful ketamine can help. But the investigation found wide-ranging inconsistencies among clinics, from the screening of patients to the dose and frequency of infusions to the coordination with patients’ mental health providers. A number of clinics stray from recommendations issued last year by the American Psychiatric Association. © 2018 Scientific American

Keyword: Depression; Drug Abuse
Link ID: 25500 - Posted: 09.27.2018

By Carolyn Y. Johnson and Joel Achenbach The allegations of sexual assault against Judge Brett M. Kavanaugh have a common element of binge drinking, and highlight the powerful effects alcohol can have on adolescents and their still-developing brains. Alcohol not only changes behavior — sometimes with disastrous consequences — it can also interfere with memory formation, creating gaps that experts refer to as blackouts. “In the moment, the person can be functioning normally, with no sign there’s going to be memory impairment. But because those memories never get consolidated and stored, it’s like they never occurred, so you can’t recall them later on,” said Kate Carey, a clinical psychologist at Brown University School of Public Health. “Which doesn’t mean it didn’t happen.” Binge drinking and the imperfection of memory are likely to be discussed during Thursday’s hearing before the Senate Judiciary Committee. Christine Blasey Ford said the Supreme Court nominee became “stumbling drunk” and attacked her at a party in high school. Kavanaugh has denied the allegation. He also said in a television interview that he’d never had a blackout from alcohol. Binge drinking among U.S. high school students peaked in the early 1980s, when Kavanaugh was a student at Georgetown Prep. High school binge drinking has declined in recent decades in part because dozens of states, as well as the District of Columbia, raised the minimum legal drinking age to 21 in the 1980s, said Katherine Keyes, an epidemiologist at Columbia University and an expert on alcohol consumption.

Keyword: Drug Abuse; Learning & Memory
Link ID: 25499 - Posted: 09.27.2018

Craig Richard Have you ever stumbled upon an hourlong online video of someone folding napkins? Or maybe crinkling paper, sorting a thimble collection or pretending to give the viewer an ear exam? They’re called ASMR videos and millions of people love them and consider watching them a fantastic way to relax. Other viewers count them among the strangest things on the internet. So are they relaxing or strange? I think they are both, which is why I have been fascinated with trying to understand ASMR for the past five years. In researching my new book “Brain Tingles,” I explored the many mysteries about ASMR as well as best practices for incorporating ASMR into various aspects of life, like parenting, spas and health studios. ASMR is short for Autonomous Sensory Meridian Response. Enthusiast Jennifer Allen coined the term in 2010. You may also hear this phenomenon called “head orgasms” or “brain tingles.” It’s distinct from the “aesthetic chills” or frisson some people experience when listening to music, for instance. People watch ASMR videos in hopes of eliciting the response, usually experienced as a deeply relaxing sensation with pleasurable tingles in the head. It can feel like the best massage in the world – but without anyone touching you. Imagine watching an online video while your brain turns into a puddle of bliss. The actions and sounds in ASMR videos mostly recreate moments in real life that people have discovered spark the feeling. These stimuli are called ASMR triggers. They usually involve receiving personal attention from a caring person. Associated sounds are typically gentle and non-threatening. © 2010–2018, The Conversation US, Inc.

Keyword: Hearing; Emotions
Link ID: 25498 - Posted: 09.27.2018

Laura Sanders Nearly two out of three U.S. kids spend more than two hours a day looking at screens, a new analysis of activity levels finds. And those children perform worse on memory, language and thinking tests than kids who spend less time in front of a device, the study of over 4,500 8- to 11-year-olds shows. The finding, published online September 26 in Lancet Child & Adolescent Health, bolsters concerns that heavy use of smartphones, tablets or televisions can hurt growing minds. But because the study captures a single snapshot in time, it’s still not known whether too much screen time can actually harm brain development, experts caution. Researchers used data gleaned from child and parent surveys on daily screen time, exercise and sleep, collected as part of a larger effort called the Adolescent Brain Cognitive Development Study. Cognitive abilities were also tested in that bigger study. As a benchmark for the new study, the researchers used expert guidelines set in 2016 that recommend no more than two hours of recreational screen time a day, an hour of exercise and between nine and 11 hours of nighttime sleep. Overall, the results are concerning, says study coauthor Jeremy Walsh, an exercise physiologist who at the time of the study was at the Children’s Hospital of Eastern Ontario Research Institute in Ottawa, Canada. Only 5 percent of the children met all three guidelines on screen time, exercise and sleep, the survey revealed. Twenty-nine percent of the children didn’t meet any of the guidelines, meaning that “they’re getting less than nine hours of sleep, they’re on their screens for longer than two hours and they’re not being physically active,” Walsh says. “This raises a flag.” |© Society for Science & the Public 2000 - 2018.

Keyword: Development of the Brain
Link ID: 25497 - Posted: 09.27.2018

By Sam Rose Imagine the following transformation. A pea-sized chunk of your skin breaks apart in a dish of salts and serums. The mixture is infected with viruses that make some cells smaller, more circular, and clump together. They’ve turned into stem cells. Then, a bath of other salts, serums, and factors coax them into becoming mature neurons. The neurons divide and organize themselves into three dimensional spheres. Inside the spheres, the neurons layer themselves like the neurons in your cerebral cortex. There’s not just one ball, but an army of tiny spheres. Each sphere contains thousands of neurons; each neuron with a copy of your DNA. The neurons communicate with each other with pulses of electricity. The spheres start to organize structures that look a lot like the different lobes and substructures of your brain. Some of the spheres may even form an optic cup, an early version of your retina. This may seem like a perverse form of human cloning carried out by a neuroscientist turned witch-doctor. But it’s real: an emerging laboratory model system that might one day help treat you or a loved one’s debilitating neurological disorder. They are called brain spheroids (or three-dimensional brain cultures or cerebral organoids) and are a relatively new creation. They were first described in a splashy study published in Nature in 2013 and are one of the most technically impressive forms of tissue culture. What brain spheroids are not, however, is as important as what they are. They’re not ‘mini-brains’. They’re not generating thoughts and emotions. Without any sensory input they lack grounding in the physical world. Brain spheroids are also very small. At 4 mm in diameter, they’re much smaller than a mouse’s brain. They’re this small because real developing brains need massive amounts of nutrients throughout the depth of their structure. Brain spheroids get their nutrients from a bath of serums. But without a network of blood vessels to deliver the serum to deeper parts of the spheroid, these parts starve. Attaching a functioning circulatory system to the spheroids isn’t feasible with current techniques, so making bigger, more developed spheroids seems unlikely at this point. © 2018 Scientific American

Keyword: Development of the Brain
Link ID: 25496 - Posted: 09.26.2018

By Benedict Carey and Jan Hoffman When Judge Brett M. Kavanaugh and Christine Blasey Ford present their vastly different recollections to the Senate on Thursday, the quality and reliability of memory itself will be on trial. Judge Kavanaugh has emphatically denied allegations from Dr. Blasey that he tried to rape her when they were teenagers or ever committed sexual assault against anyone. Dr. Blasey and another accuser, Deborah Ramirez, have recounted their alleged incidents with both precise detail and gaping holes. Could Judge Kavanaugh’s accusers be mistaken about his identity? Could he somehow have erased the experiences they allege from his memory? Or, even, could all be telling what they genuinely believe is the truth? The biology of memory, while still far from worked out, helps to explain how vastly different accounts can emerge from a shared experience. Memory, by its nature and necessity, is selective, its details subject to revision and dissipation. From the dizzying stream of incoming perceptions, the brain stores, or “encodes,” the sights, sounds, sensations and emotions that it deems important or novel. The quality of preservation may depend not only on the intensity of emotion in the moment an event occurs but on the mechanics of how that event is recorded and retrieved — in some cases, decades later. “Recollection is always a reconstruction, to some extent — it’s not a videotape that preserves every detail,” said Richard J. McNally, a professor of psychology at Harvard University and the author of “Remembering Trauma.” “The details are often filled in later, or dismissed, and guessing may become part of the memory.” For a trauma victim, this encoding combines mortal fear and heart-racing panic with crystalline fragments of detail: the make of the gun, the color of the attacker’s eyes. The emotion is so strong that the fragments can become untethered from time and place. They may persist in memory even as other relevant details—the exact date, the conversation just before the attack, who else was in the room — fall out of reach. © 2018 The New York Times Company

Keyword: Learning & Memory
Link ID: 25495 - Posted: 09.26.2018

Denis Campbell Health policy editor Eating junk food increases the risk of becoming depressed, a study has found, prompting calls for doctors to routinely give dietary advice to patients as part of their treatment for depression. In contrast, those who follow a traditional Mediterranean diet are much less likely to develop depression because the fish, fruit, nuts and vegetables that diet involves help protect against Britain’s commonest mental health problem, the research suggests. Published in the journal Molecular Psychiatry, the findings have come from an analysis by researchers from Britain, Spain and Australia who examined 41 previous studies on the links between diet and depression. “A pro-inflammatory diet can induce systemic inflammation, and this can directly increase the risk for depression,” said Dr Camille Lassale, the study’s lead author. Bad diet heightens the risk of depression to a significant extent, she added. The analysis found that foods containing a lot of fat or sugar, or was processed, lead to inflammation of not just the gut but the whole body, known as “systemic inflammation”. In that respect the impact of poor diet is like that of smoking, pollution, obesity and lack of exercise. © 2018 Guardian News and Media Limited

Keyword: Depression; Obesity
Link ID: 25494 - Posted: 09.26.2018

April Fulton Within three days of starting high school this year, my ninth-grader could not get into bed before 11 p.m. or wake up by 6 a.m. He complained he couldn't fall asleep but felt foggy during the school day and had to reread lessons a few times at night to finish his homework. And forget morning activities on the weekends — he was in bed. We're not the only family struggling to get restful shut-eye. "What parents are sharing with us is that the 'normal life' of a typical American high schooler is interfering with sleep," says Sarah Clark, co-director of C.S. Mott Children's Hospital National Poll on Children's Health at the University of Michigan. In the poll of 2,000 parents from various ethnic groups and backgrounds that Clark and her team published this month, 1 in 6 parents say their teen experiences frequent sleep problems — "having trouble falling asleep or staying asleep 3 or more nights per week." More than half the parents say it's because their teens won't get off their electronic devices, and 43 percent blame irregular schedules with homework and activities. A significant percentage of parents say their kids worry about school (31 percent), and 23 percent say their teens stay up worrying about their social lives. It's likely that the numbers of teens who have trouble sleeping is even higher than the poll of parents suggests, Clark says, because kids can hide their nighttime electronics use and parents may not frequently check in on older children. How can parents help? Start with knowing what kids need. © 2018 npr

Keyword: Sleep; Development of the Brain
Link ID: 25493 - Posted: 09.26.2018

Nathaniel Comfort It’s never a good time for another bout of genetic determinism, but it’s hard to imagine a worse one than this. Social inequality gapes, exacerbated by climate change, driving hostility towards immigrants and flares of militant racism. At such a juncture, yet another expression of the discredited, simplistic idea that genes alone control human nature seems particularly insidious. And yet, here we are again with Blueprint, by educational psychologist Robert Plomin. Although Plomin frequently uses more civil, progressive language than did his predecessors, the book’s message is vintage genetic determinism: “DNA isn’t all that matters but it matters more than everything else put together”. “Nice parents have nice children because they are all nice genetically.” And it’s not just any nucleic acid that matters; it is human chromosomal DNA. Sorry, microbiologists, epigeneticists, RNA experts, developmental biologists: you’re not part of Plomin’s picture. Crude hereditarianism often re-emerges after major advances in biological knowledge: Darwinism begat eugenics; Mendelism begat worse eugenics. The flowering of medical genetics in the 1950s led to the notorious, now-debunked idea that men with an extra Y chromosome (XYY genotype) were prone to violence. Hereditarian books such as Charles Murray and Richard Herrnstein’s The Bell Curve (1994) and Nicholas Wade’s 2014 A Troublesome Inheritance (see N. Comfort Nature 513, 306–307; 2014) exploited their respective scientific and cultural moments, leveraging the cultural authority of science to advance a discredited, undemocratic agenda. Although Blueprint is cut from different ideological cloth, the consequences could be just as grave. © 2018 Springer Nature Limited.

Keyword: Genes & Behavior; Intelligence
Link ID: 25492 - Posted: 09.26.2018

Laura Sanders With the help of a spine stimulator and intensive training, a formerly paralyzed man can command his legs to step again. This achievement, described online September 24 in Nature Medicine, inches researchers closer to restoring movement to paraplegic people. The therapy allows 29-year-old Jered Chinnock to control his leg movements with his thoughts. “This is highly significant,” study coauthor Kendall Lee, a neurosurgeon at the Mayo Clinic in Rochester, Minn., said in a news briefing on September 20. A snowmobile wreck left Chinnock paralyzed, unable to move or feel sensations below the chest. His initial rehabilitation focused on acclimating to life in a wheelchair. But three years after the accident, he enrolled in an aggressive study designed to get him moving. Surgeons implanted a stimulator that zaps nerve cells on the spinal cord below the site of Chinnock’s injury. With the stimulator on, therapists led Chinnock through exercises to reactivate muscles and nerves. Over two weeks of training with the stimulator, he could stand and, while lying on his side, make voluntary steplike movements. Those results were published last year in Mayo Clinic Proceedings. Now, after 43 weeks of intense rehabilitation, Chinnock has made even greater strides. He can step on a treadmill on his own, and, with assistance and a walker, can step across the ground. Over the course of one training session, he was able to travel 102 meters, about the length of an American football field, the researchers report. Because he required assistance, researchers describe Chinnock’s motion as “independent stepping” rather than walking. That’s because, in clinical terms, walking describes “a highly coordinated activity in terms of balance, strength and adaptation to the environment,” said Lee’s coauthor Kristin Zhao, also of the Mayo Clinic. |© Society for Science & the Public 2000 - 2018.

Keyword: Movement Disorders; Robotics
Link ID: 25491 - Posted: 09.25.2018

Jacek Debiec Most of what you experience leaves no trace in your memory. Learning new information often requires a lot of effort and repetition – picture studying for a tough exam or mastering the tasks of a new job. It’s easy to forget what you’ve learned, and recalling details of the past can sometimes be challenging. But some past experiences can keep haunting you for years. Life-threatening events – things like getting mugged or escaping from a fire – can be impossible to forget, even if you make every possible effort. Recent developments in the Supreme Court nomination hearings and the associated #WhyIDidntReport action on social media have rattled the public and raised questions about the nature, role and impact of these kinds of traumatic memories. Leaving politics aside, what do psychiatrists and neuroscientists like me understand about how past traumas can remain present and persistent in our lives through memories? Imagine facing extreme danger, such as being held at gunpoint. Right away, your heart rate increases. Your arteries constrict, directing more blood to your muscles, which tense up in preparation for a possible life-or-death struggle. Perspiration increases, to cool you down and improve gripping capability on palms and feet for added traction for escape. In some situations, when the threat is overwhelming, you may freeze and be unable to move. Threat responses are often accompanied by a range of sensations and feelings. Senses may sharpen, contributing to amplified detection and response to threat. You may experience tingling or numbness in your limbs, as well as shortness of breath, chest pain, feelings of weakness, fainting or dizziness. Your thoughts may be racing or, conversely, you may experience a lack of thoughts and feel detached from reality. Terror, panic, helplessness, lack of control or chaos may take over. Copyright © 2010–2018

Keyword: Learning & Memory; Stress
Link ID: 25490 - Posted: 09.25.2018

By Jean Rhodes, Mary Waters In the aftermath of Hurricane Florence, news coverage has shifted to focus on the storm’s destructive toll and the survivors’ efforts to restore their shattered lives and communities. But there is another side to the story that will go mostly unnoticed: disasters can set the stage for profound personal and societal growth. In August 2005, just before Hurricane Katrina struck, we were part of a team of researchers collecting data in 10 U.S. cities for a study of community college students. The New Orleans site consisted of mostly young black women, many living in the 9th ward, where some of the worst destruction and trauma would occur. In the midst of the post-Katrina mayhem we realized that we had a rare opportunity. We had pre-disaster data and could control for how survivors were functioning prior to the storm, so we were uniquely positioned to explore the long-term effects of the disaster. Over the course of more than a decade of research we have uncovered surprising findings about recovery and resilience—including that over 60 percent of the survivors have bounced back to pre-disaster levels of mental health.But perhaps most surprising has been the deep psychological growth that has emerged from the depths of despair. © 2018 Scientific American

Keyword: Stress
Link ID: 25489 - Posted: 09.25.2018

Anthea Lacchia Just 10 minutes of light physical activity is enough to boost brain connectivity and help the brain to distinguish between similar memories, a new study suggests. Scientists at the University of California studying brain activity found connectivity between parts of the brain responsible for memory formation and storage increased after a brief interval of light exercise – such as 10 minutes of slow walking, yoga or tai chi. The findings could provide a simple and effective means of slowing down or staving off memory loss and cognitive decline in people who are elderly or have low levels of physical ability. The scientists asked 36 healthy volunteers in their early 20s to do 10 minutes of light exercise – at 30% of their peak oxygen intake – before assessing their memory ability. The memory test was then repeated on the same volunteers without exercising. The same experiment was repeated on 16 of the volunteers who had either undertaken the same kind of exercise or rested, with researchers scanning their brain to monitor activity. In the brains of those who had exercised they discovered enhanced communication between the hippocampus – a region important in memory storage – and the cortical brain regions, which are involved in vivid recollection of memories. “The memory task really was quite challenging,” said Michael Yassa, a neuroscientist at the University of California, Irvine, and project co-leader. The participants were first shown pictures of objects from everyday life – ranging from broccoli to picnic baskets – and later tested on how well they remembered the images. “We used very tricky similar items to to see if they would remember whether it was this exact picnic basket versus that picnic basket,” he said. © 2018 Guardian News and Media Limited

Keyword: Learning & Memory
Link ID: 25488 - Posted: 09.25.2018

Sukanya Charuchandra Previous research has shown that the gut-brain connection, which refers to signaling between the digestive and the central nervous systems, is based on the transport of hormones, but a study published today (September 21) in Science suggests there may be a more direct link—the vagus nerve. This research presents “a new set of pathways that use gut cells to rapidly communicate with . . . the brain stem,” Daniel Drucker, who studies gut disorders at the Lunenfeld-Tanenbaum Research Institute in Toronto, Canada, and was not involved with the project, tells Science. Building on an earlier study in which the team found that gut cells had synapses, the researchers injected a rabies virus, expressing green fluorescence, into the stomachs of mice and watched it travel speedily from the intestines to the rodents’ brainstems. When they grew sensory gut cells together with neurons from the vagus nerve, the neurons moved across the dish to form synapses with the gut cells and began electrically coupling with them. Adding sugar to the dish sped up the rate of signaling between the gut and brain cells, a finding that suggests glutamate, a neurotransmitter involved in sensing taste, may be key to the process. Blocking glutamate secretion in gut cells brought these signals to a grinding halt. © 1986 - 2018 The Scientist.

Keyword: Obesity
Link ID: 25487 - Posted: 09.25.2018

by Marvin M. Lipman, ‘I thought I had Parkinson’s disease!” the 65-year-old stock analyst exclaimed. Over the past six months, her handwriting had deteriorated to the point that she was having difficulty signing checks. Because a good friend of hers had recently received a diagnosis of Parkinson’s disease, she feared the worst. I began to suspect that her concern was groundless when I noticed that both of her hands shook and that she had a barely noticeable to-and-fro motion of her head — two signs that are uncommon in Parkinson’s disease. And as she walked toward the examining room, her gait was normal and her arms swung freely — hardly the stiff, hesitant shuffle so often seen with Parkinson’s. The exam turned up none of the other cardinal manifestations of Parkinson’s: the typical masklike facial expression; the slowed, monotonous speech pattern; and the ratchet-like sensation the examiner feels when alternately flexing and extending the patient’s arm. Moreover, her hand tremors seemed to improve at rest and worsen when asked to do the “finger to nose” test. The diagnosis was unmistakable: She had essential tremor, a nervous-system problem that causes unintentional shaking, most often starting in the hands. © 1996-2018 The Washington Post

Keyword: Movement Disorders
Link ID: 25486 - Posted: 09.25.2018

Roland S. Liblau The events that lead to the sleep disorder narcolepsy are a long-standing mystery. Writing in Nature, Latorre et al.1 reveal that people with narcolepsy have unusually high levels of a type of immune cell called a T cell, which targets proteins normally present in neurons in the brain. This finding raises the question of whether narcolepsy arises because T cells unleash an autoimmune response against neurons that are important for sleep regulation. Narcolepsy affects around 1 in 2,000 people2. The symptoms usually begin in adolescence or early adulthood, and include daytime sleepiness and, in some cases, cataplexy — sudden muscle weakness during wakefulness that causes falls. A small population of neurons in the brain produces a protein called hypocretin, which controls sleep–wake cycles3, and narcolepsy-like symptoms occur in animals that have defects in genes required for the production of or response to hypocretin4. Narcolepsy type 2 is associated with daytime sleepiness, and this can progress to narcolepsy type 1, which is characterized by sleepiness and cataplexy. People with narcolepsy type 1 have abnormally low numbers of hypocretin-producing neurons5. Hypocretin levels in the cerebrospinal fluid that bathes the brain and spinal cord can be measured to help diagnose6 narcolepsy type 1, and such tests provide a way of indirectly monitoring the loss of hypocretin-producing neurons over time. The trajectory of this neuronal loss remains to be fully understood, but can take months or years. © 2018 Springer Nature Limited.

Keyword: Narcolepsy; Neuroimmunology
Link ID: 25485 - Posted: 09.24.2018

By Henry Nicholls A fresh-faced batch of teenagers just began a new school year, but will they get the most out of it? In the mornings, many are forced to get to school much too early. And at night, ubiquitous screens are a lure that’s hard to resist. This double whammy is a perfect lesson in sleep deprivation. Three out of every four students in grades 9 to 12 fail to sleep the minimum of eight hours that the American Academy of Sleep Medicine recommends for their age group. And sleep deprivation is unremittingly bad news. Anyone who talks about sleep as if it’s some kind of inconvenience and getting less of it is a virtue should be challenged. These people are dangerous. At its most basic, insufficient sleep results in reduced attention and impaired memory, hindering student progress and lowering grades. More alarmingly, sleep deprivation is likely to lead to mood and emotional problems, increasing the risk of mental illness. Chronic sleep deprivation is also a major risk factor for obesity, Type 2 diabetes, hypertension, cardiovascular disease and cancer. As if this weren’t enough, it also makes falling asleep at the wheel much more likely. It is important to understand why teenagers have a particularly hard time getting enough sleep, and what adults need to do to help. First, a reminder of the basic biology: After puberty, adolescents are no longer the morning larks of their younger years. They become rewired as night owls, staying awake later and then sleeping in. This is not part of a feckless project to frustrate parents, but is driven by changes in the way the brain responds to light. © 2018 The New York Times Company

Keyword: Biological Rhythms; Development of the Brain
Link ID: 25484 - Posted: 09.24.2018