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People who want to quit smoking are more likely to succeed if they go "cold turkey" by stopping abruptly, a study in Annals of Internal Medicine shows. Volunteers who used this approach were 25% more likely to remain abstinent half a year from the date that they give up than smokers who tried to gradually wean themselves off instead. The NHS says that picking a convenient date to quit is important. Make a promise, set a date and stick to it, it advises. And sticking to the "not a drag" rule can really help too. "Whenever you find yourself in difficulty say to yourself, 'I will not have even a single drag' and stick with this until the cravings pass," the service says. And it recommends seeing a GP to get professional support and advice to give up smoking. In the British Heart Foundation-funded study, nearly 700 UK volunteers were randomly assigned to one of two groups - a gradual quit group or an immediate quit group. All of the participants were also offered advice and support and access to nicotine patches and replacement therapy, like nicotine gum or mouth spray - services which are available for free on the NHS. After six months, 15.5% of the participants in the gradual-cessation group were abstinent compared with 22% in the abrupt-cessation group. Lead researcher Dr Nicola Lindson-Hawley, from Oxford University, said: "The difference in quit attempts seemed to arise because people struggled to cut down. It provided them with an extra thing to do, which may have put them off quitting altogether." Even though more people in the study said they preferred the idea of quitting gradually than abruptly, individuals were still more likely to stop for good in the abrupt group. © 2016 BBC.
Keyword: Drug Abuse
Link ID: 21993 - Posted: 03.16.2016
The CDC recommends non-opioid therapy, including exercise and over-the-counter pain medications, as the preferred treatment for chronic pain. It says opioids should only be prescribed — at the lowest effective dosage possible — when the benefits from pain reduction and bodily function outweigh the risks. In 2014, American doctors wrote nearly 200 million prescriptions for opioid painkillers, while deaths linked to the drugs climbed to roughly 19,000 — the highest number on record. The number of Canadians who die every year from opioids is not readily known — the Canadian Centre on Substance Abuse does not track the statistics — but Toronto physician Nav Persaud told CBC News in 2014 that more than 1,000 Canadians die from painkillers every year. A 2012 study says one in eight deaths among young adults age 25 to 34 in Ontario and one out of every 170 deaths in the province as a whole are opioid overdoses. One in four people who entered a withdrawal management program at St. Joseph's Healthcare in Hamilton, Ont., were opioid patients in 2012, up from one in ten in 2002. Other studies have cast doubt on the effectiveness of opioids on chronic pain, raising questions on whether its limited long-term effects are worth the harmful risks. "The science is clear," CDC director Tom Frieden said Tuesday. "For the vast majority of patients, the known and often fatal risks [of opioids] far outweigh the proven and transient benefits." ©2016 CBC/Radio-Canada.
Keyword: Pain & Touch; Drug Abuse
Link ID: 21992 - Posted: 03.16.2016
Linda Geddes The health effects of a bad diet can carry over to offspring through eggs and sperm cells without DNA mutations, researchers have found. The mouse study, published in Nature Genetics1, provides some of the strongest evidence yet for the non-genetic inheritance of traits acquired during an organism’s lifetime. And although previous work has suggested that sperm cells can carry 'epigenetic' factors, this is the first time that such an effect has been observed with egg cells. Researchers have suspected for some time that parents' lifestyle and behaviour choices can affect their children's health through epigenetics. These are chemical modifications to DNA or the proteins in chromosomes that affect how genes are expressed, but that do not alter the gene sequences themselves. Whether those changes can be inherited is still controversial. In particular, there have been suggestions that parental eating habits might shape the offspring's risk of obesity and diabetes. However, it has been difficult to disentangle the possibility that the parents’ behaviour during pregnancy or during the offspring's early childhood was to blame, rather than epigenetic changes that had occurred before conception. To get around this issue, endocrinologist Peter Huypens at the German Research Center for Environmental Health in Neuherberg, Germany, and his colleagues gave genetically identical mice one of three diets — high fat, low fat or standard laboratory chow — for six weeks. As expected, those fed the high-fat diet became obese and had impaired tolerance to glucose, an early sign of type 2 diabetes. © 2016 Nature Publishing Group
Keyword: Obesity; Epigenetics
Link ID: 21991 - Posted: 03.15.2016
By ERICA GOODE Their websites show peaceful scenes — young women relaxing by the ocean or caring for horses in emerald pastures — and boast of their chefs and other amenities. One center sends out invitations to a reception with cocktails and hors d’oeuvres. Another offers doctors and therapists all-expense-paid trips to visit and experience their offerings, including yoga classes. Several employ staff who call mental health professionals, saying they would love to have lunch. The marketing efforts by these for-profit residential care centers are aimed at patients with eating disorders and the clinicians who treat them. The programs have proliferated in recent years, with some companies expanding across the country. The rapid growth of the industry — there are more than 75 centers, compared with 22 a decade ago, according to one count — has been propelled by the Affordable Care Act and other changes in health insurance laws that have increased coverage for mental disorders, as well as by investments from private equity firms. The residential programs, their directors say, fill a dire need, serving patients from areas where no adequate treatment is available. “Only 15 to 30 percent of people have access to specialized care for eating disorders, which means there are a lot of people out there who have zippo,” said Doug Bunnell, the chief clinical officer for Monte Nido, a program that began in Malibu, Calif., and now operates centers in five states. But the advertising and the profusion of centers, which typically cost $1,000 a day but can run much higher, is raising concerns among some eating disorders experts, who worry that some programs may be taking advantage of vulnerable patients and their families. In the companies’ rush to expand, they argue, quality of treatment may be sacrificed for profit. And they question whether the spalike atmosphere of some programs is so comfortable that it fosters dependency. © 2016 The New York Times Company
Keyword: Anorexia & Bulimia
Link ID: 21990 - Posted: 03.15.2016
How did evolution produce a monstrous killer like T. rex? A fossil find in Central Asia is giving scientists a glimpse of the process. T. rex and other tyrannosaurs were huge, dominant predators, but they evolved from much smaller ancestors. The new discovery from Uzbekistan indicates that this supersizing happened quickly, and only after the appearance of some anatomical features that may have helped the monster tyrannosaurs hunt so effectively. The finding was reported Monday by Hans-Dieter Sues of the Smithsonian's National Museum of Natural History in Washington, Stephen Brusatte of the University of Edinburgh in Scotland, and others in a paper released by the Proceedings of the National Academy of Sciences. The discovery They report finding bones of a previously unknown member of the evolutionary branch that led to the huge tyrannosaurs. This earlier dinosaur lived about 90 million years ago, south of what is now the Aral Sea. It looked roughly like a T. rex, but was only about 10 to 12 feet long and weighed only about 600 pounds at most, Sues said. T. rex grew about four times as long and weighed more than 20 times as much. The discovery helps fill in a frustrating gap in the tyrannosaur fossil record. Before that gap, which began some 100 million years ago, the ancestral creatures were only about as big as a horse. Right after the gap, at about 80 million years ago, tyrannosaurs were multi-ton behemoths like T. rex. The new finding shows the forerunners were still relatively small even just 90 million years ago. So the size boom happened pretty quickly. Standard equipment ©2016 CBC/Radio-Canada.
Keyword: Evolution
Link ID: 21989 - Posted: 03.15.2016
By Perri Klass, M.D. I got my good sleeper second. My oldest child, my first darling baby, did not reliably sleep through the night till he was well past 2. Since he is now an adult, I can skip right over all the questions of whether we could have trained him to self-soothe and stop calling for us in the night — we tried; we failed; we eventually gave up. The good sleeper was a good sleeper right from the beginning. She followed the timeline in the books, slept longer and longer between feedings, till she was reliably giving us a real night while she was still an infant and she never looked back. Had we matured as parents, become less anxious, more willing to let her learn how to soothe herself? Were our lives calmer? Well, no. In fact, kind of the opposite. We just got dealt two very different babies. I supervise pediatric residents as they learn to provide primary care, to offer guidance to parents as they struggle with all the complexities of baby and toddler sleep, eating, potty training, discipline and tantrums. All of the stuff that shapes your daily life with a small child, and I’m talking about an essentially healthy, normally developing small child. And the hardest thing to teach, especially to people who haven’t yet done any child-rearing, is how different those healthy, normal babies can be, right from the beginning. So we review our sensible pediatric rubrics that deal with these questions, from establishing good sleep patterns to setting limits to encouraging a healthy varied diet. But sometimes it seems that these rubrics work best with the children and families who need them least. Every child is a different assignment — and we can all pay lip service to that cheerfully enough. But the hard thing to believe is how different the assignments can be. Within the range of developmentally normal children, some parents have a much, much harder job than others: more drudge work, less gratification, more public shaming. It sometimes feels like the great undiscussed secret of pediatrics — and of parenting © 2016 The New York Times Company
Keyword: Development of the Brain
Link ID: 21988 - Posted: 03.15.2016
By ANDREW POLLACK An experimental drug derived from marijuana has succeeded in reducing epileptic seizures in its first major clinical trial, the product’s developer announced on Monday, a finding that could lend credence to the medical marijuana movement. The developer, GW Pharmaceuticals, said the drug, Epidiolex, achieved the main goal of the trial, reducing convulsive seizures when compared with a placebo in patients with Dravet syndrome, a rare form of epilepsy. GW shares more than doubled on Monday. If Epidiolex wins regulatory approval, it would be the first prescription drug in the United States that is extracted from marijuana. The drug is a liquid containing cannabidiol, a component of marijuana that does not make people high. As many as 30 percent of the nearly 500,000 American children with epilepsy are not sufficiently helped by existing drugs, according to GW. Parents of some of these children have been flocking to try marijuana extracts, prepared by medical marijuana dispensaries. A number of states, in response to pressure from these parents, have passed or considered legislation to make it easier to obtain marijuana-based products. And some families have become “marijuana refugees,” moving to Colorado where it has been easier to obtain a particular extract, known as Charlotte’s Web, after the girl who first used it to control seizures. Hundreds of other children and young adults have been using Epidiolex outside of clinical trials, under programs that allow desperate patients to use experimental drugs. While many parents have reported significant reductions in seizures, experts have been cautious about anecdotal reports, saying that such treatments needed to be compared with a placebo to make sure they work. As such, the results from the GW trial have been closely watched. © 2016 The New York Times Company
Keyword: Epilepsy; Drug Abuse
Link ID: 21987 - Posted: 03.15.2016
By Sandra G. Boodman Kim Pace was afraid he was dying. In six months he had lost more than 30 pounds because a terrible stabbing sensation on the left side of his face made eating or drinking too painful. Brushing his teeth was out of the question and even the slightest touch triggered waves of agony and a shocklike pain he imagined was comparable to electrocution. Painkillers, even morphine, brought little relief. Unable to work and on medical leave from his job as a financial consultant for a bank, Pace, then 59, had spent the first half of 2012 bouncing among specialists in his home state of Pennsylvania, searching for help from doctors who disagreed about the nature of his illness. Some thought his searing pain might be the side effect of a drug he was taking. Others suspected migraines, a dental problem, mental illness, or an attempt to obtain painkillers. Even after a junior doctor made what turned out to be the correct diagnosis, there was disagreement among specialists about its accuracy or how to treat Pace. His wife, Carol, a nurse, said she suspects that the couple’s persistence and propensity to ask questions led her husband to be branded “a difficult case” — the kind of patient whom some doctors avoid. And on top of that, a serious but entirely unrelated disorder further muddied the diagnostic picture. So on July 17, 2012, when Pace told his wife he thought he was dying, she fired off an emotional plea for help to the office of a prominent specialist in Baltimore. “I looked at Kim and it hit me: He was going to die,” she said. “He was losing weight and his color was ashen” and doctors were “blowing him off. I thought, ‘Okay, that’s it,’ and the nurse in me took over.”
Keyword: Pain & Touch; Epilepsy
Link ID: 21986 - Posted: 03.15.2016
By Julia Shaw Our brains play tricks on us all the time, and these tricks can mislead us into believing we can accurately reconstruct our personal past. In reality, false memories are everywhere. False memories are recollections of things that you never actually experienced. These can be small memory errors, such as thinking you saw a yield sign when you actually saw a stop sign, or big errors like thinking you took a hot air balloon ride that never actually happened. If you want to know more about how we can come to misremember complex autobiographical events, here is a recipe and here is a video with footage from my own research. A few weeks ago I reached out to see what you actually wanted to know about this phenomenon on Reddit, and here are the answers to my six favorite questions. 1. Is there any way a person can check if their own memories are real or false? The way that I have interpreted the academic literature, once they take hold false memories are no different from true memories in the brain. This means that they have the same properties as any other memories, and are indistinguishable from memories of events that actually happened. The only way to check, is to find corroborating evidence for any particular memory that you are interested in “validating”. © 2016 Scientific American
Keyword: Learning & Memory
Link ID: 21985 - Posted: 03.15.2016
By BARBARA K. LIPSKA AS the director of the human brain bank at the National Institute of Mental Health, I am surrounded by brains, some floating in jars of formalin and others icebound in freezers. As part of my work, I cut these brains into tiny pieces and study their molecular and genetic structure. My specialty is schizophrenia, a devastating disease that often makes it difficult for the patient to discern what is real and what is not. I examine the brains of people with schizophrenia whose suffering was so acute that they committed suicide. I had always done my work with great passion, but I don’t think I really understood what was at stake until my own brain stopped working. In the first days of 2015, I was sitting at my desk when something freakish happened. I extended my arm to turn on the computer, and to my astonishment realized that my right hand disappeared when I moved it to the right lower quadrant of the keyboard. I tried again, and the same thing happened: The hand disappeared completely as if it were cut off at the wrist. It felt like a magic trick — mesmerizing, and totally inexplicable. Stricken with fear, I kept trying to find my right hand, but it was gone. I had battled breast cancer in 2009 and melanoma in 2012, but I had never considered the possibility of a brain tumor. I knew immediately that this was the most logical explanation for my symptoms, and yet I quickly dismissed the thought. Instead I headed to a conference room. My colleagues and I had a meeting scheduled to review our new data on the molecular composition of schizophrenia patients’ frontal cortex, a brain region that shapes who we are — our thoughts, emotions, memories. But I couldn’t focus on the meeting because the other scientists’ faces kept vanishing. Thoughts about a brain tumor crept quietly into my consciousness again, then screamed for attention. © 2016 The New York Times Company
Keyword: Consciousness; Vision
Link ID: 21984 - Posted: 03.14.2016
Deborah Orr The psychologist Oliver James has for many years been a part of the cultural landscape, writing best-selling books, making television programmes, contributing articles to newspapers and generally offering his views. As a practicing psychotherapist of many years’ standing, he has good reason to believe that he has important insights to offer. James is particularly exercised by the damage caused by casual emotional abuse – the explosive parent who shouts and swears at their kids, displays resentment against them or tries to coerce them into doing things instead of employing reason. No sensible person disagrees with him on this, and only a harsh critic would deny that James has played a strong and positive part in popularising these simple, important wisdoms. That’s why it’s so very odd that James has chosen now to perpetrate casual emotional abuse on a grand scale. His latest book, Not in Your Genes: The Real Reason Parents Are Like Their Children, expands on an argument he’s been making for years: that there is no scientific basis for belief in the idea that there is any genetic element to any psychological trait. Even illnesses such as schizophrenia and bipolar disorder are completely down to the environment in which you grew up, not the complex interplay between nature and nurture that mainstream science espouses. Even if James had conclusive evidence to back up his absolutist claim – which he does not – I would suggest that such news should be broken gently. © 2016 Guardian News and Media Limited
Keyword: Development of the Brain; Genes & Behavior
Link ID: 21983 - Posted: 03.14.2016
A senior British doctor, who has been an expert defence witness for parents accused of killing their children, has been found guilty of multiple charges that include giving misleading evidence in court. The Medical Practitioners Tribunal Service said that Waney Squier, a consultant pathologist at John Radcliffe Hospital in Oxford, UK, had failed to work within the limits of her competence, failed to be objective and unbiased, and failed to heed the views of other experts. In many of the cases investigated, her actions were deliberately misleading and irresponsible. The MPTS had considered Squier’s work as an expert witness in six child abuse cases and one appeal in which parents faced charges of non-accidental head injury, formerly known as shaken-baby syndrome. Squier is prominent among several researchers worldwide who have challenged a long-standing belief that a trio of symptoms of head injury provide unequivocal evidence of abusive behaviour. Squier has argued in the scientific literature and in court that the symptoms in question – haemorrhages on the surface of the brain, haemorrhages in the retinas, and a swollen brain – can have innocent causes, such as choking or other difficulties in breathing. These symptoms, they say, can also arise from the birthing process itself. Michele Codd, chair of the tribunal, gave examples of where the panel felt Squier’s court evidence had strayed outside her field of expertise. These included offering opinions on biomechanics in relation to injuries from falling, pathology of the eyes, and paediatric medicine. © Copyright Reed Business Information Ltd.
Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 21982 - Posted: 03.14.2016
By HEATHER MURPHY Good morning. Or confusing morning, really. Come Daylight Saving Time each year, people often complain about how thrown off they feel by the shift of an hour. I thought they were just whiny. That is, until my dinosaur got jet lag and refused to glow. Since that’s not an everyday occurrence, let me explain the dinosaur first, and then I’ll get to how my dinosaur’s problems may be connected to your own struggles to function over the next few days. (Hint: It’s not only the loss of sleep that causes problems.) Created by a company called BioPop, my Dino Pet contains lots of itty bitty dinoflagellates. Dinoflagellates, if you are having trouble summoning a sixth-grade biology lesson, are usually ocean-dwelling, single-celled organisms also known as marine plankton. People typically encounter them when they clean the inside of their aquarium (this form is often referred “brown slime algae”) or if they happen to be kayaking through a bay filled with lots of bioluminescent ones. The ones that live in my plastic dinosaur (a Christmas gift) are the latter kind. Shake them just a bit and the transparent creatures become a glow-in-the-dark snow globe. Except that a week after I set my dinosaur up, it still refused to put on its shimmer show. I tried everything. I moved it from darker to lighter spots. I played it music and whispered encouraging words. But when I turned off the lights, my little dino remained depressingly dark. © 2016 The New York Times Company
Keyword: Biological Rhythms
Link ID: 21981 - Posted: 03.14.2016
By Emily Underwood Nestled deep within a brain region that processes memory is a sliver of tissue that continually sprouts brand-new neurons, at least into late adulthood. A study in mice now provides the first glimpse at how these newborn neurons behave in animals as they learn, and hints at the purpose of the new arrivals: to keep closely-related but separate memories distinct. A number of previous studies have suggested that the birth of new neurons is key to memory formation. In particular, scientists believe the new cell production—known as neurogenesis—plays a role in pattern separation, the ability to discriminate between similar experiences, events, or contexts based on sensory cues such as a certain smell or visual landmark. Pattern separation helps us use cues such as the presence of a particular tree or cars nearby, for example, to distinguish which parking space we chose today, as opposed to yesterday or the day before. This ability appears to be particularly diminished in people with anxiety and mood disorders. Scientists can produce deficits in pattern separation in animals by blocking neurogenesis, using x-ray radiation to kill targeted populations of cells in the dentate gyrus. Because such studies have not established the precise identity of which cells are being recorded from, however, no one has been able to address the “burning question” in the field: "how young, adult-born neurons and mature dentate granule neurons differ in their activity," says Amar Sahay, a neuroscientist at the Massachusetts General Hospital and Harvard Medical School. © 2016 American Association for the Advancement of Scienc
Keyword: Neurogenesis; Learning & Memory
Link ID: 21980 - Posted: 03.12.2016
Sara Reardon Elite ski jumpers rely on extreme balance and power to descend the steep slopes that allow them to reach up to 100 kilometres per hour. But the US Ski and Snowboard Association (USSA) is seeking to give its elite athletes an edge by training a different muscle: the mind. Working with Halo Neuroscience in San Francisco, California, the sports group is testing whether stimulating the brain with electricity can improve the performance of ski jumpers by making it easier for them to hone their skills. Other research suggests that targeted brain stimulation can reduce an athlete’s ability to perceive fatigue1. Such technologies could aid recovery from injury or let athletes try 'brain doping' to gain a competitive advantage. Yet many scientists question whether brain stimulation is as effective as its proponents claim, pointing out that studies have looked at only small groups of people. “They’re cool findings, but who knows what they mean,” says cognitive psychologist Jared Horvath at the University of Melbourne in Australia. The USSA is working with Halo to judge the efficacy of a device that delivers electricity to the motor cortex, an area of the brain that controls physical skills. The company claims that the stimulation helps the brain build new connections as it learns a skill. It tested its device in an unpublished study of seven elite Nordic ski jumpers, including Olympic athletes. © 2016 Nature Publishing Group,
Keyword: Movement Disorders
Link ID: 21979 - Posted: 03.12.2016
How is the brain able to use past experiences to guide decision-making? A few years ago, researchers supported by the National Institutes of Health discovered in rats that awake mental replay of past experiences is critical for learning and making informed choices. Now, the team has discovered key secrets of the underlying brain circuitry – including a unique system that encodes location during inactive periods. “Advances such as these in understanding cellular and circuit-level processes underlying such basic functions as executive function, social cognition, and memory fit into NIMH’s mission of discovering the roots of complex behaviors,” said NIMH acting director Bruce Cuthbert, Ph.D. While a rat is moving through a maze — or just mentally replaying the experience — an area in the brain’s memory hub, or hippocampus, specialized for locations, called CA1, communicates with a decision-making area in the executive hub or prefrontal cortex (PFC). A distinct subset of PFC neurons excited during mental replay of the experience are activated during movement, while another distinct subset, less engaged during movement in the maze – and therefore potentially distracting – are inhibited during replay. “Such strongly coordinated activity within this CA1-PFC circuit during awake replay is likely to optimize the brain’s ability to consolidate memories and use them to decide on future action” explained Shantanu Jadhav, Ph.D. (link is external), now an assistant professor at Brandeis University, Waltham, MA., the study’s co-first author. His contributions to this line of research were made possible, in part, by a Pathway to Independence award from the Office of Research Training and Career Development of the NIH’s National Institute of Mental Health (NIMH).
Keyword: Learning & Memory; Attention
Link ID: 21978 - Posted: 03.12.2016
By Kj Dell’Antonia New research shows that the youngest students in a classroom are more likely to be given a diagnosis of attention deficit hyperactivity disorder than the oldest. The findings raise questions about how we regard those wiggly children who just can’t seem to sit still – and who also happen to be the youngest in their class. Researchers in Taiwan looked at data from 378,881 children ages 4 to 17 and found that students born in August, the cut-off month for school entry in that country, were more likely to be given diagnoses of A.D.H.D. than students born in September. The children born in September would have missed the previous year’s cut-off date for school entry, and thus had nearly a full extra year to mature before entering school. The findings were published Thursday in The Journal of Pediatrics. While few dispute that A.D.H.D. is a legitimate disability that can impede a child’s personal and school success and that treatment can be effective, “our findings emphasize the importance of considering the age of a child within a grade when diagnosing A.D.H.D. and prescribing medication for treating A.D.H.D.,” the authors concluded. Dr. Mu-Hong Chen, a member of the department of psychiatry at Taipei Veterans General Hospital in Taiwan and the lead author of the study, hopes that a better understanding of the data linking relative age at school entry to an A.D.H.D. diagnosis will encourage parents, teachers and clinicians to give the youngest children in a grade enough time and help to allow them to prove their ability. Other research has shown similar results. An earlier study in the United States, for example, found that roughly 8.4 percent of children born in the month before their state’s cutoff date for kindergarten eligibility are given A.D.H.D. diagnoses, compared to 5.1 percent of children born in the month immediately afterward. © 2016 The New York Times Company
Keyword: ADHD; Development of the Brain
Link ID: 21977 - Posted: 03.12.2016
By Dominic Howell BBC News Gum disease has been linked to a greater rate of cognitive decline in people with Alzheimer's disease, early stage research has suggested. The small study, published in PLOS ONE, looked at 59 people who were all deemed to have mild to moderate dementia. It is thought the body's response to gum inflammation may be hastening the brain's decline. The Alzheimer's Society said if the link was proven to be true, then good oral health may help slow dementia. The body's response to inflammatory conditions was cited as a possible reason for the quicker decline. Inflammation causes immune cells to swell and has long been associated with Alzheimer's. Researchers believe their findings add weight to evidence that inflammation in the brain is what drives the disease. 'Six-fold increase' The study, jointly led by the University of Southampton and King's College London, cognitively assessed the participants, and took blood samples to measure inflammatory markers in their blood. Their oral health was also assessed by a dental hygienist who was unaware of the cognitive outcomes. Of the sample group, 22 were found to have considerable gum disease while for the remaining 37 patients the disease was much less apparent. The average age of the group with gum disease was 75, and in the other group it was 79. A majority of participants - 52 - were followed up at six months, and all assessments were repeated. The presence of gum disease - or periodontitis as it is known - was associated with a six-fold increase in the rate of cognitive decline, the study suggested. © 2016 BBC
Keyword: Alzheimers
Link ID: 21976 - Posted: 03.12.2016
Carl Zimmer Scientists recently turned Harvard’s Skeletal Biology Laboratory into a pop-up restaurant. It would have fared very badly on Yelp. Katherine D. Zink, then a graduate student, acted as chef and waitress. First, she attached electrodes to the jaws of diners to record the activity in the muscles they use to chew food. Then she brought out the victuals. Some volunteers received a three-course vegetarian meal of carrots, yams or beets. In one course, the vegetables were cooked; in the second, they were raw and sliced; in the last course, Dr. Zink simply served raw chunks of plant matter. Other patrons got three courses of meat (goat, in this case). Dr. Zink grilled the meat in the first course, but offered it raw and sliced in the second. In the third course, her volunteers received an uncooked lump of goat flesh. In some of the trials, the volunteers chewed the food until it was ready to swallow and then spat it out. Dr. Zink painstakingly picked apart those food bits and measured their size. Every week, we'll bring you stories that capture the wonders of the human body, nature and the cosmos. “If that was all my dissertation was, I would have quit graduate school,” Dr. Zink said. “It was as lovely as it sounds.” Dr. Zink persevered, however, because she was exploring a profound question about our origins: How did our ancestors evolve from small-brained, big-jawed apes into large-brained, small-jawed humans? Scientists studying the fossil record have long puzzled over this transition, which happened around two million years ago. Before then, early human relatives — known as hominins — were typically about the size of chimpanzees, with massive teeth and a brain only a third the size of humans’ current brains. © 2016 The New York Times Company
Keyword: Evolution; Obesity
Link ID: 21975 - Posted: 03.10.2016
By Jerome Siegel To say whether an animal sleeps requires that we define sleep. A generally accepted definition is that sleep is a state of greatly reduced responsiveness and movement that is homeostatically regulated, meaning that when it is prevented for a period of time, the lost time is made up—an effect known as sleep rebound. Unfortunately, the application of this definition is sometimes difficult. Can an animal sleep while it is moving and responsive? How unresponsive does an animal have to be? How much of the lost sleep has to be made up for it to be considered homeostatically regulated? Is the brain activity that characterizes sleep in humans necessary and sufficient to define sleep in other animals? Apart from mammals, birds are the only other animals known to engage in both slow-wave and rapid eye movement (REM) sleep. Slow-wave sleep, also called non-REM sleep, is characterized by slow, high-amplitude waves of electrical activity in the cortex and by slow, regular respiration and heart rate. During REM sleep, animals exhibit a waking-like pattern of cortical activity, as well as physiological changes including jerky eye twitches and increased variability of heart rate and respiration. (See “The A, B, Zzzzs.”) But many more animals, including some insects and fish, engage in behaviors that might be called sleep, such as resting with slow but regular respiration and heart rates and a desensitization to environmental stimuli. In addition to diversity in the neural and physiological correlates of sleep, species vary tremendously in the intensity, frequency, and duration of sleep. Some animals tend to nap intermittently throughout the day, while others, including humans, tend to consolidate their sleep into a single, long slumber. The big brown bat is the current sleep champion, registering 20 hours per day; giraffes and elephants doze less than four hours daily. © 1986-2016 The Scientist
Keyword: Sleep; Evolution
Link ID: 21974 - Posted: 03.10.2016