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By Allison Bond, Although neurologist Amie Hsia was hundreds of miles away from the emergency room team caring for her ailing aunt last February, she knew her symptoms and imaging pointed to a severe stroke. Hsia’s aunt needed treatment fast with a clot-busting medicine and a procedure known as an endovascular thrombectomy, which removes the clot and restores blood flow to oxygen-starved patches of the brain. The hospital caring for her wasn’t equipped to perform the surgery, however, so Hsia insisted she be transferred to a nearby hospital, where the clot was removed from her brain. Hsia’s aunt survived and is able to live independently, despite some remaining symptoms from the stroke. Still, the travel to another hospital cost her valuable time—and could have hurt her in the long run. That’s the implication of a study published Monday in the Journal of the American Medical Association that found that the sooner patients with severe strokes receive a thrombectomy, the less disabled they tend to be three months later. The research indicates that the brain-saving benefits of thrombectomy are most pronounced within the first few hours after signs of a stroke begin, and that these effects decline with each passing hour. To some experts, the study is a call to rejigger the current method of determining where ambulances ought to take stroke patients, which is based solely on proximity. Instead, they say, patients with apparent severe strokes should be rushed to hospitals that perform thrombectomies. © 2016 Scientific America
Link ID: 22703 - Posted: 09.28.2016
By Nick Purdon, Leonardo Palleja, CBC News If you met Lisa James, chances are you'd never guess she injects herself with heroin twice a day. She's a devoted mom to her daughter Tia, 24, who has a rare neurological disorder that causes tumours to grow on her spine and brain. She comforts Tia when she's overcome with nausea. She's by her side when she visits doctors. "My relationship with my daughter is better than it's ever been," says James, 48. But James says it wasn't so long ago, her days were spent doing absolutely anything to score heroin. She used to steal hundreds of dollars' worth of meat from grocery stores and sell it on the streets. She even stole from Tia. "I took $500 out of her account and because of the lovely girl that she is, she never wanted to make me feel bad," James says. "If someone had told me I would do something so despicable — I never would have believed it." She says that all changed when she was accepted to the Providence Crosstown Clinic in Vancouver's Downtown Eastside, where she's buzzed in every morning at 9 a.m. She sits down in a sterile room and injects a syringe full of free heroin into her arm. ©2016 CBC/Radio-Canada.
Keyword: Drug Abuse
Link ID: 22702 - Posted: 09.28.2016
Ramin Skibba. Physiologist Ivan Pavlov conditioned dogs to associate food with the sound of a buzzer, which left them salivating. Decades later, researchers discovered such training appears to block efforts to teach the animals to link other stimuli to the same reward. Dogs trained to expect food when a buzzer sounds can then be conditioned to salivate when they are exposed to the noise and a flash of light simultaneously. But light alone will not cue them to drool. This ‘blocking effect’ is well-known in psychology, but new research suggests that the concept might not be so simple. Psychologists in Belgium failed to replicate the effect in 15 independent experiments, they report this month in the Journal of Experimental Psychology1. “For a long time, you tend to think, ‘It’s me’ — I’m doing something wrong, or messing up the experiment,’” says lead author Tom Beckers, a psychologist at the Catholic University of Leuven (KU Leuven) in Belgium. But after his student, co-author Elisa Maes, also could not replicate the blocking effect, and the team failed again in experiments in other labs, Beckers realized that “it can’t just be us”. The scientists do not claim that the blocking effect is not real, or that previous observations of it are wrong. Instead, Beckers thinks that psychologists do not yet know enough about the precise conditions under which it applies. © 2016 Macmillan Publishers Limited,
Keyword: Learning & Memory
Link ID: 22701 - Posted: 09.27.2016
By Abdul-Kareem Ahmed In the world of recreational and professional sports, many athletes—particularly in contact sports—suffer concussions. These mild traumatic brain injuries cause headaches, memory problems and confusion, but usually resolve on their own with rest. Some players, however, especially after repeated concussions, continue to experience symptoms for many months—a phenomenon termed post-concussion syndrome. A few of these players will eventually develop chronic traumatic encephalopathy (CTE), a progressive neurodegenerative disease that causes dementia symptoms similar to Alzheimer’s disease. CTE can lead to personality changes, movement problems and, sometimes, mortality. CTE is diagnosed after death because it requires postmortem examination of a player’s brain. Post-concussion syndrome, in contrast, is diagnosed based on patient symptoms. To date, doctors do not have any objective tests to determine syndrome severity or relate it to the risk of developing CTE. Now, a group of researchers from Sweden and the U.K. say they have developed such a test, reporting their findings last week in JAMA Neurology. The test measures biomarkers in the cerebrospinal fluid—the colorless liquid that supports and suspends the brain and spinal cord—that appear to provide a measure of concussion severity and CTE risk. The researchers collected cerebrospinal fluid via spinal taps from 16 professional Swedish ice hockey players and a similar number of healthy individuals. The hockey players had all experienced post-concussion syndrome, causing nine of them to retire from the game. © 2016 Scientific American,
By KEN BELSON One of the frustrations of researchers who study chronic traumatic encephalopathy, the degenerative brain disease linked to repeated head hits, is that it can be detected only in autopsies, and not in the living. Researchers, though, have been trying to solve this problem in two primary ways: by identifying biomarkers linked to the disease that show up on imaging tests in certain locations in the brain, and by trying to locate in the blood the protein that is the hallmark of the disease. On Monday, two groups of researchers said they had made what they considered small steps in developing both methods. The announcements are small parts of much larger studies that will take years to bear fruit, if they ever do. Both methods have been questioned by detractors, some of whom say the hype is getting ahead of the science. Scientists, these critics note, have spent decades trying to find ways to accurately diagnose Alzheimer’s disease, which has some of the same characteristics as C.T.E. Still, at a medical conference in Boston on Monday, Robert Stern, a professor of neurology at Boston University, said technology developed by the company Quanterix (paid for in part with a grant from the N.F.L.) had identified elevated levels of tau proteins in blood samples of 96 former football players between 40 and 69 years old, compared with only 25 people of the same age in a control group. The results, which are part of a seven-year study and are under review for publication, are preliminary because they identify only the total amount of tau in the blood, not the amount of the specific tau linked to C.T.E. Additional tests are being done in Sweden to determine the amount of the C.T.E.-related tau in the blood samples, Stern said. Even so, Stern said, the blood samples from the 96 former players suggest that absorbing repeated head hits earlier in life can lead to higher concentrations of tau in the blood later. © 2016 The New York Times Company
Emma Yasinski Two often-overlooked medications might help millions of Americans who abuse alcohol to quit drinking or cut back. Public health officials, building on a push to treat people who abuse opioids with medications, want physicians to consider using medications to treat alcohol addiction. The drugs can be used in addition to or sometimes in place of peer-support programs, they say. "We want people to understand we think AA is wonderful, but there are other options," says George Koob, director of the National Institute of Alcohol Abuse and Alcoholism, a part of the federal National Institutes of Health. It is still rare for a person struggling with alcohol to hear that medication therapy exists. This partly reflects the tradition of treating addiction through 12-step programs. It's also a byproduct of limited promotion by the drugs' manufacturers and confusion among doctors about how to use them. A key study funded by the federal government reported last year that only 20 percent people who abuse alcohol will ever receive any form of treatment, which ranges from seeing a counselor or doctor to entering a specialized treatment program. The same is true for opioid addiction — about 80 percent of people dependent on opioids will never receive treatment. © 2016 npr
Keyword: Drug Abuse
Link ID: 22698 - Posted: 09.27.2016
By NICHOLAS BAKALAR Ants, like people and rats, can become addicted to morphine. Scientists divided 90 ants into three groups. The first received a solution containing morphine and sugar, which was gradually reduced until the ants were receiving pure morphine. The second group of ants got a sugar solution gradually reduced to pure water, and the third ate just sugar. Then the researchers offered all three groups the choice of sugar or morphine. The ants that had been gradually deprived of sugar and those never exposed to morphine went right back to sugar. But about two-thirds of the ants given morphine chose it over sugar. Ants are the first nonmammal to display drug-seeking behavior, the researchers said. © 2016 The New York Times Company
Keyword: Drug Abuse
Link ID: 22697 - Posted: 09.27.2016
James Gorman When the leader of a flock goes the wrong way, what will the flock do? With human beings, nobody can be sure. But with homing pigeons, the answer is that they find their way home anyway. Either the lead pigeon recognizes that it has no clue and falls back into the flock, letting birds that know where they are going take over, or the flock collectively decides that the direction that it is taking just doesn’t feel right, and it doesn’t follow. Several European scientists report these findings in a stirring report in Biology Letters titled, “Misinformed Leaders Lose Influence Over Pigeon Flocks.” Isobel Watts, a doctoral student in zoology at Oxford, conducted the study with her advisers, Theresa Burt de Perera and Dora Biro, and with the participation of Mate Nagy, a statistical physicist from Hungary, who is affiliated with several institutions, including Oxford and the Hungarian Academy of Sciences. Dr. Biro, who studies social behavior in primates as well as pigeons, said that the common questions that ran through her work were “about group living and what types of challenges and opportunities it brings.” She and her colleagues at Oxford have pioneered a method of studying flock behavior that uses very-fine-resolution GPS units, which the birds wear in pigeon-size backpacks. The devices record a detailed position for each bird a number of times a second. Researchers in Budapest and Oxford developed software to analyze small movements and responses of every bird in a flock. With this method, the scientists can identify which pigeons are leading the way. They can build a picture of how each bird responds to changes in the flight of other birds. © 2016 The New York Times Company
Jon Hamilton There's growing evidence that a physical injury to the brain can make people susceptible to post-traumatic stress disorder. Studies of troops deployed to Iraq and Afghanistan have found that service members who suffer a concussion or mild traumatic brain injury are far more likely to develop PTSD, a condition that can cause flashbacks, nightmares and severe anxiety for years after a traumatic event. And research on both people and animals suggest the reason is that a brain injury can disrupt circuits that normally dampen the response to a frightening event. The result is like "driving a car and the brake's not fully functioning," says Minxiong Huang, a biomedical physicist at the University of California, San Diego. Scientists have suspected a link between traumatic brain injury (TBI) and PTSD for many years. But the evidence was murky until researchers began studying troops returning from Iraq and Afghanistan. What they found was a lot of service members like Charles Mayer, an Army sniper from San Diego who developed PTSD after finishing a deployment in Iraq. In 2010, Mayer was on patrol in an Army Humvee near Baghdad when a roadside bomb went off. "I was unconscious for several minutes," he says. So he found out what happened from the people who dragged him out. The blast fractured Mayer's spine. It also affected his memory and thinking. That became painfully clear when Mayer got out of the Army in 2012. © 2016 npr
The make-up of the bacteria found in human faeces may influence levels of dangerous fat in our bodies, say researchers from King's College London. Their analysis of stool samples in a study of more than 3,600 twins found evidence that some of this bacteria is inherited. What is contained in faeces bacteria could therefore partly explain why obesity passes down through families. The study is published in Genome Biology. The research team extracted information from study participants about the human faecal microbiome - the bacteria present in faeces samples - and compared these to six different measures of obesity, including body mass index (BMI) and different types of body fat. The researchers found the strongest links with visceral fat, where participants with a high diversity of bacteria in their faeces had lower levels of visceral fat. This type of body fat is bad news because it is stored in the stomach area around important organs such as the liver, pancreas and intestines and is linked with higher risks of cardiovascular disease and diabetes. Dr Michelle Beaumont, lead study author from the department of twin research and genetic epidemiology at King's College London, said although the study showed a clear link, it was not yet possible to explain why it existed. One theory is that a lack of variety in faecal bacteria could lead to the domination of high levels of gut microbes which are good at turning carbohydrates into fat. © 2016 BBC.
Link ID: 22694 - Posted: 09.26.2016
By GINA KOLATA You must lose weight, a doctor told Sarah Bramblette, advising a 1,200-calorie-a-day diet. But Ms. Bramblette had a basic question: How much do I weigh? The doctor’s scale went up to 350 pounds, and she was heavier than that. If she did not know the number, how would she know if the diet was working? The doctor had no answer. So Ms. Bramblette, 39, who lived in Ohio at the time, resorted to a solution that made her burn with shame. She drove to a nearby junkyard that had a scale that could weigh her. She was 502 pounds. One in three Americans is obese, a rate that has been steadily growing for more than two decades, but the health care system — in its attitudes, equipment and common practices — is ill prepared, and its practitioners are often unwilling, to treat the rising population of fat patients. The difficulties range from scales and scanners, like M.R.I. machines that are not built big enough for very heavy people, to surgeons who categorically refuse to give knee or hip replacements to the obese, to drug doses that have not been calibrated for obese patients. The situation is particularly thorny for the more than 15 million Americans who have extreme obesity — a body mass index of 40 or higher — and face a wide range of health concerns. Part of the problem, both patients and doctors say, is a reluctance to look beyond a fat person’s weight. Patty Nece, 58, of Alexandria, Va., went to an orthopedist because her hip was aching. She had lost nearly 70 pounds and, although she still had a way to go, was feeling good about herself. Until she saw the doctor. “He came to the door of the exam room, and I started to tell him my symptoms,” Ms. Nece said. “He said: ‘Let me cut to the chase. You need to lose weight.’” © 2016 The New York Times Company
Link ID: 22693 - Posted: 09.26.2016
George Paxinos Many people today believe they possess a soul. While conceptions of the soul differ, many would describe it as an “invisible force that appears to animate us”. It’s often believed the soul can survive death and is intimately associated with a person’s memories, passions and values. Some argue the soul has no mass, takes no space and is localised nowhere. But as a neuroscientist and psychologist, I have no use for the soul. On the contrary, all functions attributable to this kind of soul can be explained by the workings of the brain. Psychology is the study of behaviour. To carry out their work of modifying behaviour, such as in treating addiction, phobia, anxiety and depression, psychologists do not need to assume people have souls. For the psychologists, it is not so much that souls do not exist, it is that there is no need for them. It is said psychology lost its soul in the 1930s. By this time, the discipline fully became a science, relying on experimentation and control rather than introspection. What is the soul? It is not only religious thinkers who have proposed that we possess a soul. Some of the most notable proponents have been philosophers, such as Plato (424-348 BCE) and René Descartes in the 17th century. Plato believed we do not learn new things but recall things we knew before birth. For this to be so, he concluded, we must have a soul. Centuries later, Descartes wrote his thesis Passions of the Soul, where he argued there was a distinction between the mind, which he described as a “thinking substance”, and the body, “the extended substance”. He wrote: © 2010–2016, The Conversation US, Inc.
Link ID: 22692 - Posted: 09.26.2016
By Michael Price A deadly disease known as African sleeping sickness has puzzled doctors for decades. It would disappear from villages without a trace, only to re-emerge weeks or months later with no known cause. Frustrated health officials wondered how sleeping sickness could persist when not a single villager or animal—the disease’s only carriers—tested positive for the insect-borne parasite that causes it. Now, scientists may have an answer at last: They’ve discovered the disease was hiding in plain sight this whole time, living in and even transmitting via human skin. African sleeping sickness, also known as African trypanosomiasis, is caused by a microscopic wormlike parasite spread exclusively by the tsetse fly. As such, it’s limited by the fly’s range to sub-Saharan Africa. Locals avoid places where the flies are numerous, but political unrest can displace residents and force them into the path of the disease. Once infected, people have anywhere from weeks to years before the parasite crashes into the brain, causing headaches, tremors, confusion, and paralysis. Those infected also suffer from a disrupted sleep cycle, bouts of random sleepiness and wakefulness that gives the disease its name. Without treatment—toxic drugs that keep patients bedridden for weeks—those infected nearly always slip into a coma and die. In the 1950s and 1960s, health officials got the number of reported cases down to a few thousand per year and were on track to eradicate it, says parasitologist Annette MacLeod of the University of Glasgow in the United Kingdom, who led the new discovery. But despite their best efforts, they could never get rid of the last few thousand cases. © 2016 American Association for the Advancement of Science.
Link ID: 22691 - Posted: 09.24.2016
By CONOR DOUGHERTY SAN FRANCISCO — Every now and again, when I’m feeling a little down, I go to Baseball-Reference.com and look up the San Francisco Giants’ box score from July 29, 2012. It’s an odd choice for a Giants fan. The Los Angeles Dodgers won, 4-0, completing a weekend sweep in which they outscored the Giants by 19-3 and tied them for the lead in the National League West. The Giants went on to win the World Series that year, but that’s not why I remember the July 29 game. I remember that afternoon because my mom, in the throes of Alzheimer’s, left the house she shared with my dad in the Noe Valley neighborhood, walked four or so miles and somehow ended up at AT&T Park. Then she went inside and watched her team. It took a while for me to believe this. When Mom told me she had gone to the park — my dad barely watches baseball, so the Giants have always been a thing between me and Mom — I assumed it was an old memory misplaced on a new day. But it turned out that Sunday game did overlap with the hours she had been out, and a month or so later my dad got a credit card bill with the charge for the ticket. I can’t tell you when Mom cheered or if she managed to find her seat. All I know is Clayton Kershaw struck out seven, the Giants had five hits, and even though I’ve committed these statistics to memory, I still like looking them up. On the chance that this hasn’t been clubbed into your head by now, the Giants have won the World Series in every even-numbered year this decade. And for reasons that I choose to see as cosmic, this run of baseball dominance has tracked my mom’s descent into Alzheimer’s. The disease doesn’t take people from you in a day or a week or a season. You get years of steady disappearance, with an indeterminate end. So for me and Mom and baseball, this decade has been a long goodbye. © 2016 The New York Times Company
Link ID: 22690 - Posted: 09.24.2016
By Dwayne Godwin, Jorge Cham The brain processes a wealth of visual information in parallel so that we perceive the world around us in the blink of an eye Dwayne Godwin is a neuroscientist at the Wake Forest University School of Medicine. Jorge Cham draws the comic strip Piled Higher and Deeper at www.phdcomics.com. © 2016 Scientific American
Link ID: 22689 - Posted: 09.24.2016
By Alison F. Takemura Bodies like to keep their pH close to 7.4, whether that means hyperventilating to make the blood alkaline, or burning energy, shifting to anaerobic metabolism, and producing lactate to make the blood acidic. The lungs and kidneys can regulate pH changes systemically, but they may not act quickly on a local scale. Because even small pH changes can dramatically affect the nervous system, a study led by Sten Grillner of Karolinska Institute in Sweden looked for a mechanism for pH homeostasis in the spinal cord. Using the lamprey as a model system, the researchers observed that a type of spinal canal neuron, called CSF-c, fired more rapidly when they bathed it with high pH (7.7) or low pH (7.1) media. They could suspend the elevated activity by blocking two ion channels: PKD2L1 channels, which stimulate neurons in alkaline conditions, or ASIC3 channels, which, the team showed previously, do the same in acidic states. As the neurons fired, they released the hormone somatostatin, which inhibited the lamprey’s locomotor network. These results suggest that, whichever direction pH deviates, “the response of the system is just to reduce activity as much as possible,” Grillner says. The pH-regulating role of CSF-c neurons is likely conserved among animals, the authors suspect, given the presence of these neurons across vertebrate taxa. © 1986-2016 The Scientist
Keyword: Movement Disorders
Link ID: 22688 - Posted: 09.24.2016
By Karl Gruber Five lionesses in Botswana have grown a mane and are showing male-like behaviours. One is even roaring and mounting other females. Male lions are distinguished by their mane, which they use to attract females, and they roar to protect their territory or call upon members of their pride. Females lack a mane and are not as vocal. . New Scientist Live: Book tickets to our festival of ideas and discovery – 22 to 25 September in London But sometimes lionesses grow a mane and even behave a bit like males. However, until now, reports of such maned lionesses have been extremely rare and largely anecdotal. We knew they existed, but little about how they behave. Now, Geoffrey D. Gilfillan at the University of Sussex in Falmer, UK, and colleagues have reported five lionesses sporting a mane at the Moremi Game Reserve in Botswana’s Okavango delta. Gilfillan started studying these lionesses back in March 2014, and for the next two years he focused on recording the behaviour of one of them, called SaF05. She had an underdeveloped mane and was larger than most females. “While SaF05 is mostly female in her behaviour – staying with the pride, mating males – she also has some male behaviours, such as increased scent-marking and roaring, as well as mounting other females,” says Gilfillan. © Copyright Reed Business Information Ltd.
By MICHAEL HEDRICK My father said on numerous occasions when I was growing up that he would see other families that had problems like divorce and drug use, and he would thank God that his family was so perfect. Things would change, though. They always do. And that perfect family would face just as much struggle as any other. Growing up in the mountains above Boulder, Colo., our life was good. My parents had left their life in Chicago behind for an ideal they saw in a piece of art they found at a flea market, a haphazardly painted picture of a cabin next to a river with the mountains towering in the background. Born in the early ‘80s, my brothers and I shared a bond as best friends in our small neighborhood, isolated from town, where we spent time outside sledding, building forts and making dams in the ditch that ran by our house. The biggest problems we seemed to face were bloody knees and the occasional broken bone from snowboarding and bike accidents. My dad, a subscriber to “Mother Earth News,” relished our family’s home in the mountains. There were backpacking trips to the national park 30 miles away, where he taught us how to build a fire and to hang our food from tree limbs to keep it out of reach of bears. Other times he would take us on long father-son road trips, where we would drive the long highways with nothing to look at but the passing fields and nothing to pay attention to but the books on tape from Focus on the Family that my father put on the car stereo. Those tapes provided a Christian look at what it meant to be a man, covering issues like lust, sex and puberty, and he’d answer our questions about girls and all manner of things relating to our growing into healthy young men. © 2016 The New York Times Company
By Mallory Locklear Men and women show different patterns of drug abuse, with women becoming addicted to some substances much more quickly. Now a study in rats has found that sex hormones can reduce opioid abuse. From studies of other drugs, such as cocaine and alcohol, we know that women are less likely to use these substances than men, but become addicted faster when they do. “There are a lot of data to indicate that women transition from that initial use to having a substance-use disorder much more rapidly,” says Mark Smith, a psychologist at Davidson College, North Carolina. Once addicted, women also seem to have stronger drug cravings. Tracking drug use throughout women’s menstrual cycles suggests that both these differences could be shaped by hormones – with more intense cravings and greater euphoria at particular times in the cycle, says Smith. Craving crash Now Smith’s team has investigated the effects of hormones on opioid addiction in rats. Their findings suggest that hormones such as oestrogen and progesterone may help women to kick the habit. The researchers allowed female rats to self-administer heroin, and measured how much they chose to take at different times in their oestrous cycle – a regular sequence of hormone fluctuations similar to those seen in the menstrual cycle in women. © Copyright Reed Business Information Ltd.
By Virginia Morell There will never be a horse like Mr. Ed, the talking equine TV star. But scientists have discovered that the animals can learn to use another human tool for communicating: pointing to symbols. They join a short list of other species, including some primates, dolphins, and pigeons, with this talent. Scientists taught 23 riding horses of various breeds to look at a display board with three icons, representing wearing or not wearing a blanket. Horses could choose between a “no change” symbol or symbols for “blanket on” or “blanket off.” Previously, their owners made this decision for them. Horses are adept at learning and following signals people give them, and it took these equines an average of 10 days to learn to approach and touch the board and to understand the meaning of the symbols. All 23 horses learned the entire task within 14 days. They were then tested in various weather conditions to see whether they could use the board to tell their trainers about their blanket preferences. The scientists report online in Applied Animal Behaviour Science that the horses did not touch the symbols randomly, but made their choices based on the weather. If it was wet, cold, and windy, they touched the "blanket on" icon; horses that were already wearing a blanket nosed the “no change” image. But when the weather was sunny, the animals touched the "blanket off" symbol; those that weren’t blanketed pressed the “no change” icon. The study’s strong results show that the horses understood the consequences of their choices, say the scientists, who hope that other researchers will use their method to ask horses more questions. © 2016 American Association for the Advancement of Science.