By Max Evans BBC News A stranger once waved at Boo James on a bus. She did not think any more of it - until it later emerged it was her mother. She has a relatively rare condition called face blindness, which means she cannot recognise the faces of her family, friends, or even herself. Scientists have now launched a study they hope could help train people like Boo to recognise people better. Boo said for many years she thought she was "from another planet". "It is immensely stressful and very emotionally upsetting to sit and dwell upon so I try not to do that," she said. "It's very hard work. It can be physically and emotionally exhausting to spend a day out in public constantly wondering whether you should have spoken to someone." For most of her life, she didn't know she had the condition - also known as prosopagnosia - and blamed herself for the "social awkwardness" caused when she failed to recognise people. "I had to try and find a way to explain that. I really couldn't very well, except to think that I was just the one to blame for not being bothered to remember who people were. "[Like it was] some sort of laziness: I didn't want to know them, obviously I wasn't interested enough to remember them, so that was some kind of deficiency, perhaps, in me." But the penny dropped in her early 40s when she saw a news item about the condition on television. "I then knew that the only reason I wasn't recognising that person was because my brain physically wasn't able to do it," she said. "I could immediately engage more self-understanding and forgive myself and try to approach things from a different angle." Image caption Boo has developed techniques to try to help her cope, including remembering what people wear She said her childhood was punctuated by "traumatic experiences" with fellow children, childminders and teachers she could not recognise. © 2019 BBC

Keyword: Attention
Link ID: 26011 - Posted: 03.06.2019

Carolyn Wilke Over the course of human evolution, our brains expanded massively. One of the areas that ballooned over the past few million years is the cerebral cortex, the wrinkly outer layer of the brain. It processes sensory information, coordinates our motion, and is in charge of our higher order functions, such as language processing and problem solving. Scientists are scrutinizing the structure of the cortex for clues about its development throughout our lives and our evolution as a species and to understand where heredity intersects with intelligence. A new study of hundreds of developing brains reveals a trifecta of overlap in regions of the cortical surface that develop from childhood to adulthood, expanded during evolution, and are connected to genetics. The scientists also found genetically mediated links between IQ test scores and surface area in regions related to intelligence, they report today (March 4) in the Journal of Neuroscience. “I think it’s a very, very strong work,” says Rachel Brouwer, a neuroscientist at University Medical Center Utrecht in the Netherlands who was not part of the study. The authors pick up which regions of the brain where variability is most explained by genes, but by looking for connections with evolutionary expansion and neurodevelopment, “it is an attempt to link [heritability] to what it actually means in a broader picture,” she says. © 1986 - 2019 The Scientist

Keyword: Intelligence; Evolution
Link ID: 26010 - Posted: 03.06.2019

Rob Stein There's strong new evidence that a common childhood vaccine is safe. A large study released Monday finds no evidence that the vaccine that protects against measles, mumps and rubella increases the risk of autism. The study of children born in Denmark is one of the largest ever of the MMR vaccine. "The study strongly supports that MMR vaccination does not increase the risk for autism," the authors write in the Annals of Internal Medicine. "We believe our results offer reassurance and provide reliable data." The study's first author, epidemiologist Anders Hviid of the Staten Serum Institute in Copenhagen, added in an email: "MMR does not cause autism." In the study, researchers analyzed data collected from all children born in Denmark to Danish-born mothers between 1999 and 2010. Among the 657,461 children included in the analysis, 6,517 were diagnosed with autism over the next decade. But there was no overall increased risk for the developmental disorder among those who received the MMR vaccine when compared with those who had not gotten the vaccine, the researchers found. The researchers also found no increased risk among subgroups of children who might be unusually susceptible to autism, such as those with a brother or sister with the disorder. © 2019 npr

Keyword: Autism
Link ID: 26009 - Posted: 03.06.2019

Robin McKie Matt Ellison was seven when his father was diagnosed with Huntington’s disease. The condition – which is progressive, incurable and invariably fatal – took 15 years to kill John Ellison. The impact on Matt’s life was profound. His father, who had inherited the disease from his mother, found he could no longer concentrate enough to hold down his job as an engineer at Jaguar. Later he began to lose the power of movement and, eventually, lost his ability to speak. At his local school Matt was mocked because of his father’s odd, uncoordinated gait. The taunting got so bad that Matt stopped attending. “I stayed at home and helped Mum look after Dad,” he recalls. Then in 2007, when Matt reached 18, he decided to find out whether he faced a similar fate. He was tested and told: yes, he had the Huntington’s gene. A few years later his father died, aged 55. “I had had time to prepare myself, but it still hits you hard when you are told you are positive,” says Matt. “I had wanted to be negative as much for my mum, who had gone through enough pain.” For Matt, and thousands of others who have been told they have inherited this affliction, the future would appear bleak, a prospect of inexor able physical and mental decline. The Huntington’s gene is remorseless in its impact. But recently this dark outlook has brightened. Scientists believe they are closing in on a treatment to control Huntington’s worst effects. © 2019 Guardian News & Media Limited

Keyword: Huntingtons
Link ID: 26008 - Posted: 03.05.2019

By Karen Weintraub For decades researchers have focused their attacks against Alzheimer’s on two proteins, amyloid beta and tau. Their buildup in the brain often serves as a defining indicator of the disease. Get rid of the amyloid and tau, and patients should do better, the thinking goes. But drug trial after drug trial has failed to improve patients’ memory, agitation and anxiety. One trial of a drug that removes amyloid even seemed to make some patients worse. The failures suggest researchers were missing something. A series of observations and recently published research findings have hinted at a somewhat different path for progression of Alzheimer’s, offering new ways to attack a disease that robs memories and devastates the lives of 5.7 million Americans and their families. One clue hinting at the need to look further afield was a close inspection of the 1918 worldwide flu pandemic, which left survivors with a higher chance of later developing Alzheimer’s or Parkinson’s. A second inkling came from the discovery that the amyloid of Alzheimer’s and the alpha-synuclein protein that characterizes Parkinson’s are antimicrobials, which help the immune system fight off invaders. The third piece of evidence was the finding in recent years, as more genes involved in Alzheimer’s have been identified, that traces nearly all of them to the immune system. Finally, neuroscientists have paid attention to cells that had been seen as ancillary—“helper” or “nursemaid” cells. They have come to recognize these brain cells, called microglia and astrocytes, play a central role in brain function—and one intimately related to the immune system. © 2019 Scientific American

Keyword: Alzheimers; Neuroimmunology
Link ID: 26007 - Posted: 03.05.2019

By Andrew Jacobs CAMBRIDGE, Mass. — There’s a new war raging in health care, with hundreds of millions of dollars at stake and thousands of lives in the balance. The battle, pitting drug companies against doctors and patient advocates, is being fought over the unlikeliest of substances: human excrement. The clash is over the future of fecal microbiota transplants, or F.M.T., a revolutionary treatment that has proved remarkably effective in treating Clostridioides difficile, a debilitating bacterial infection that strikes 500,000 Americans a year and kills 30,000. The therapy transfers fecal matter from healthy donors into the bowels of ailing patients, restoring the beneficial works of the community of gut microbes that have been decimated by antibiotics. Scientists see potential for using these organisms to treat diseases from diabetes to cancer. At the heart of the controversy is a question of classification: Are the fecal microbiota that cure C. diff a drug, or are they more akin to organs, tissues and blood products that are transferred from the healthy to treat the sick? The answer will determine how the Food and Drug Administration regulates the procedure, how much it costs and who gets to profit. In 2013, the F.D.A. announced a draft decision to regulate the therapy as a new drug but said it would continue to study the matter before reaching a final decision — which is expected to happen soon. Critics say that approach is based on outdated science and could lead to increased costs for patients, most of whom currently rely on a nonprofit stool bank in Cambridge. At stake, some researchers say, is the future of pioneering therapies that harness the human microbiome — the trillions of organisms that colonize the body and are increasingly seen as critical for healthy brain development and immune function. © 2019 The New York Times Company

Keyword: Obesity
Link ID: 26006 - Posted: 03.05.2019

/ By Jonathan S. Jones Newly unsealed documents from a lawsuit by the state of Massachusetts allege that Purdue Pharma, maker of OxyContin and other addictive opioids, actively sniffed out new, sinister ways to cash in on the opioid crisis. Despite years of negative press coverage, unwanted attention from regulators, multimillion dollar fines and several major lawsuits, Purdue staff and owners sought to expand the company’s sights beyond its usual array of opioid painkillers. Purdue planned to become an “end-to-end pain provider,” by branching into the market for opioid addiction and overdose medicines, looking to peddle these medicines even while the company continued to aggressively market its addictive opioids. Internal research materials coldly explained the rationale behind this plan: “Pain treatment and addiction are naturally linked.” As thousands of Americans continue to overdose on opioids annually, Purdue’s secret marketing research predicted that sales of naloxone, the overdose reversal drug, and buprenorphine, a medicine used to treat opioid addiction, would increase exponentially. Addiction to Purdue’s opioids would thus drive the sale of the company’s opioid addiction and overdose medicines. Purdue even planned to target as customers patients already taking the company’s opioids and doctors who prescribed opioids excessively, according to the Massachusetts lawsuit filing. To keep the plan quiet, Purdue staff dubbed the scheme “Project Tango.” Copyright 2019 Undark

Keyword: Drug Abuse
Link ID: 26005 - Posted: 03.05.2019

Assessing the patterns of energy use and neuronal activity simultaneously in the human brain improves our understanding of how alcohol affects the brain, according to new research by scientists at the National Institutes of Health. The new approach for characterizing brain energetic patterns could also be useful for studying other neuropsychiatric diseases. A report of the findings is now online in Nature Communications. “The brain uses a lot of energy compared to other body organs, and the association between brain activity and energy utilization is an important marker of brain health,” said George F. Koob, Ph.D., director of the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of NIH, which funded the study. “This study introduces a new way of characterizing how brain activity is related to its consumption of glucose, which could be very useful in understanding how the brain uses energy in health and disease.” The research was led by Dr. Ehsan Shokri-Kojori and Dr. Nora D. Volkow of the NIAAA Laboratory of Neuroimaging. Dr. Volkow is also the director of the National Institute on Drug Abuse at NIH. In previous studies they and their colleagues have shown that alcohol significantly affects brain glucose metabolism, a measure of energy use, as well as regional brain activity, which is assessed through changes in blood oxygenation. “The findings from this study highlight the relevance of energetics for ensuring normal brain function and reveal how it is disrupted by excessive alcohol consumption,” says Dr. Volkow.

Keyword: Drug Abuse; Brain imaging
Link ID: 26004 - Posted: 03.05.2019

Laura Sanders Fast waves of activity ripple in the brain a half second before a person calls up a memory. The finding, published in the March 1 Science, hint that these brain waves might be a key part of a person’s ability to remember. The results come from a study of 14 people with epilepsy who had electrodes placed on their brains as part of their treatment. Those electrodes also allowed scientists to monitor neural activity while the people learned pairs of words. One to three minutes after learning the pairs, people were given one word and asked to name its partner. As participants remembered the missing word, neuroscientist and neurosurgeon Kareem Zaghloul and his colleagues caught glimpses of fast brain waves rippling across parts of the brain at a rate of around 100 per second. These ripples appeared nearly simultaneously in two brain regions — the medial temporal lobe, which is known to be important for memory, and the temporal association cortex, which has a role in language. When a person got the answer wrong, or didn’t answer at all, these coordinated ripples were less likely to be present, the researchers found. “We see this happening, and then we see people remember,” says Zaghloul, of the National Institutes of Health in Bethesda, Md. While recalling a memory, “you mentally jump back in time and re-experience it,” Zaghloul says. Just after the ripples, the researchers saw telltale signs of that mental time travel — an echo of brain activity similar to the brain activity when the memory of the word pair was first formed. |© Society for Science & the Public 2000 - 201

Keyword: Learning & Memory
Link ID: 26003 - Posted: 03.05.2019

By Paula Span Donna Kaye Hill realized that her 80-year-old mother was faltering cognitively when her phone suddenly stopped working. When Ms. Hill called the phone company, “they told me she hadn’t paid her bill in three months.” Finding other alarming evidence of memory gaps, she took her mother, Katie, to a memory clinic. A geriatrician there diagnosed dementia and recommended two prescription drugs and a dietary supplement, a form of vitamin E. Katie Hill dutifully took vitamin E capsules, along with a host of other medications, until she died four years later. As she declined, her daughter didn’t think the vitamin, or the two prescription medications, was making much difference. “But if it doesn’t hurt, if there’s a chance it helps even a tiny bit, why not?” she reasoned. Ms. Hill, 62, a retired public employee in Danville, Va., takes fish oil capsules daily herself, hoping they’ll help ward off the disease that killed her mother. The elder Ms. Hill was unusual only in that a doctor had recommended the supplement; most older Americans are taking them without medical guidance. The Food and Drug Administration estimates that 80 percent of older adults rely on dietary supplements, many purporting to prevent or treat Alzheimer’s and other forms of dementia. Last month, the F.D.A. cracked down on this burgeoning market, sending warning letters or advisories to 17 companies selling about 60 supplements with names like Cogni-Flex and Mind Ignite. The warnings pointed out that the companies had touted these products as working like Alzheimer’s drugs, “but naturally and without side effects.” Or as “clinically shown to help diseases of the brain, such as Alzheimer’s.” The pills, oils and capsules were said to treat other diseases, too, from stroke to erectile dysfunction. © 2019 The New York Times Company

Keyword: Alzheimers
Link ID: 26002 - Posted: 03.02.2019

Analysis of genetic data from more than 94,000 individuals has revealed five new risk genes for Alzheimer’s disease, and confirmed 20 known others. An international team of researchers also reports for the first time that mutations in genes specific to tau, a hallmark protein of Alzheimer’s disease, may play an earlier role in the development of the disease than originally thought. These new findings support developing evidence that groups of genes associated with specific biological processes, such as cell trafficking, lipid transport, inflammation and the immune response, are “genetic hubs” that are an important part of the disease process. The study, which was funded in part by the National Institute on Aging (NIA) and other components of the National Institutes of Health, follows results from 2013. It will be published online February 28, 2019 in the journal Nature Genetics . “This continuing collaborative research into the genetic underpinnings of Alzheimer’s is allowing us to dig deeper into the complexities of this devastating disease,” said Richard J. Hodes, M.D., director of the NIA. “The size of this study provides additional clarity on the genes to prioritize as we continue to better understand and target ways to treat and prevent Alzheimer’s.” The researchers, members of the International Genomic Alzheimer’s Project (IGAP), analyzed both rare and common gene variants in 94,437 individuals with late onset Alzheimer’s disease, the most common form of dementia in older adults. IGAP is made up of four consortia in the United States and Europe that have been working together since 2011 on genome-wide association studies (GWAS) involving thousands of DNA samples and shared datasets. GWAS are aimed at detecting variations in the genome that are associated with Alzheimer’s. Understanding genetic variants is helping researchers define the molecular mechanisms that influence disease onset and progression.

Keyword: Alzheimers; Genes & Behavior
Link ID: 26001 - Posted: 03.02.2019

Laura Sanders People often fret about television time for children. A new study examines the habit at the other end of life. The more television older people watched, the worse they recalled a list of words, researchers report online February 28 in Scientific Reports. But the study describes only a correlation; it can’t say that lots of TV time actually causes the memory slips. Researchers examined data on 3,590 people collected as part of the English Longitudinal Study of Aging, a long-running study of English people aged 50 and older. In 2008 and 2009, participants reported how many hours a day, on average, they spent watching television. In addition to the surveys, participants listened to a recording of 10 common words, one word every two seconds. Then, people tried to remember as many words as they could, both immediately after hearing the words and after a short delay. Six years later, people took the same tests. People who watched more than 3.5 hours of TV daily back in 2008 or 2009 were more likely to have worse verbal memory scores six years later, the researchers found. Television “dose” seemed to matter: Beyond that 3.5-hour threshold, the more TV people watched, the bigger their later verbal memory scores declined. It’s not known whether television time actually causes verbal memory problems. The reverse could be true: People who have worse memories might be more likely to watch more television. Still, the researchers suggest that TV might cause a certain kind of mental stress that might contribute to memory trouble. |© Society for Science & the Public 2000 - 2019

Keyword: Learning & Memory
Link ID: 26000 - Posted: 03.02.2019

Matthew Warren Cue the super-mouse. Scientists have engineered mice that can see infrared light normally invisible to mammals — including humans. To do so, they injected into the rodents’ eyes nanoparticles that convert infrared light into visible wavelengths1. Humans and mice, like other mammals, cannot see infrared light, which has wavelengths slightly longer than red light — between 700 nanometres and 1 millimetre. But Tian Xue, a neuroscientist at the University of Science and Technology of China in Hefei, and his colleagues developed nanoparticles that convert infrared wavelengths into visible light. The nanoparticles absorb photons at wavelengths of around 980 nanometres and emit them at shorter wavelengths, around 535 nanometres, corresponding to green light. Xue’s team attached the nanoparticles to proteins that bind to photoreceptors — the cells in the eye that convert light into electrical impulses — and then injected them into mice. The researchers showed that the nanoparticles successfully attached to the photoreceptors, which in turn responded to infrared light by producing electrical signals and activating the visual-processing areas of the brain. The team conducted experiments to show that the mice did actually detect and respond to infrared light.

Keyword: Vision
Link ID: 25999 - Posted: 03.01.2019

Laura Sanders In the understory of Central American cloud forests, musical mice trill songs to one another. Now a study of the charismatic creatures reveals how their brains orchestrate these rapid-fire duets. The results, published in the March 1 Science, show that the brains of singing mice split up the musical work. One brain system directs the patterns of notes that make up songs, while another coordinates duets with another mouse, which are carried out with split-second precision. The study suggests that “a quirky animal from the cloud forest of Costa Rica could give us a brand new insight,” into the rapid give-and-take in people’s conversations, says study coauthor Michael Long, a neuroscientist at New York University’s School of Medicine. Quirks abound in these mice, known as Alston’s singing mice (Scotinomys teguina). Like famous singers with extreme green room demands, these mice are “kind of divas,” Long says, requiring larger terrariums, exercise equipment and a very special diet. In the lab, standard mouse chow doesn’t cut it; instead, singing mice feast on fresh meal worm, dry cat food and fresh fruits and berries, says Bret Pasch. The biologist at Northern Arizona University in Flagstaff has studied these singing mice for years but wasn’t involved in this study. The mice are also, of course, loud. “They’re very vocal,” particularly in the confines of a lab, Pasch says. “Once an animal calls, it’s like a symphony that goes off,” with repeating calls. In the wild, these duets are thought to attract mates and stake out territory. |© Society for Science & the Public 2000 - 2019.

Keyword: Animal Communication; Sexual Behavior
Link ID: 25998 - Posted: 03.01.2019

Nicola Davis A pair of twins have stunned researchers after it emerged that they are neither identical nor fraternal – but something in between. The team say the boy and girl, now four years old, are the second case of semi-identical twins ever recorded, and the first to be spotted while the mother was pregnant. The situation was a surprise to the researchers. An ultrasound of the 28-year old mother at six weeks suggested the twins were identical – with signs including a shared placenta. But it soon became clear all was not as it seemed. “What happened was the mother came back for her routine ultrasound some months later, and we saw one [twin] to be a boy and one to be a girl,” said Dr Michael Gabbett, first author of the report from Queensland University of Technology in Australia. “At that point we started the genetic studies and worked it out from there.” Twins are normally either identical or fraternal. In the case of identical, one egg is fertilised by one sperm, but the resulting ball of cells splits in two, giving rise to two offspring with identical genetic material. In the case of fraternal, or non-identical, twins, two eggs are fertilised, each by a different sperm. The resulting siblings arise from the same pregnancy, but are no more genetically similar than siblings from the same parents born at a different time. Faced with a puzzling scenario, Gabbett and colleagues report in the New England Journal of Medicine that they took samples from the two amniotic sacs, allowing them to investigate the genomes of the twins during the pregnancy. © 2019 Guardian News & Media Limited

Keyword: Sexual Behavior; Development of the Brain
Link ID: 25997 - Posted: 03.01.2019

By Daisy Yuhas, Spectrum Steve Slavin was 48 years old when a visit to a psychologist’s office sent him down an unexpected path. At the time, he was a father of two with a career in the music industry, composing scores for advertisements and chart toppers. But he was having a difficult year. He had fewer clients than usual, his mother had been diagnosed with cancer, and he was battling anxiety and depression, leading him to shutter his recording studio. Slavin’s anxiety—which often manifested as negative thoughts and routines characteristic of obsessive-compulsive disorder (OCD)—was nothing new. As a child, he had often felt compelled to swallow an even number of times before entering a room, or to swallow and count—one foot in the air—to four, six or eight before stepping on a paving stone. As an adult, he frequently became distressed in crowds, and he washed his hands over and over to avoid being contaminated by other people’s germs or personalities. His depression, too, was familiar—and had caused him to withdraw from friends and colleagues. This time, as Slavin’s depression and anxiety worsened, his doctor referred him to a psychologist. “I had had an appointment booked for weeks and weeks and months,” he recalls. But about 10 minutes into his first session, the psychologist suddenly changed course: Instead of continuing to ask him about his childhood or existing mental-health issues, she wanted to know whether anyone had ever talked to him about autism.

Keyword: Autism; OCD - Obsessive Compulsive Disorder
Link ID: 25996 - Posted: 03.01.2019

By Carolyn Y. Johnson The negative health effects of skimping on sleep during the week can’t be reversed by marathon weekend sleep sessions, according to a sobering new study. Researchers have long known that routine sleep deprivation can cause weight gain and increase other health risks, including diabetes. But for those who force themselves out of bed bleary-eyed every weekday after too few hours of shut-eye, hope springs eternal that shutting off the alarm on Saturday and Sunday will repay the weekly sleep debt and reverse any ill effects. The research, published in Current Biology, crushes those hopes. Despite complete freedom to sleep in and nap during a weekend recovery period, participants in a sleep laboratory who were limited to five hours of sleep on weekdays gained nearly three pounds over two weeks and experienced metabolic disruption that would increase their risk for diabetes over the long term. While weekend recovery sleep had some benefits after a single week of insufficient sleep, those gains were wiped out when people plunged right back into their same sleep-deprived schedule the next Monday. “If there are benefits of catch-up sleep, they’re gone when you go back to your routine. It’s very short-lived,” said Kenneth Wright, director of the sleep and chronobiology laboratory at the University of Colorado at Boulder, who oversaw the work. “These health effects are long-term. It’s kind of like smoking once was — people would smoke and wouldn’t see an immediate effect on their health, but people will say now that smoking is not a healthy lifestyle choice. I think sleep is in the early phase of where smoking used to be.” Clifford Saper, head of neurology at Beth Israel Deaconess Medical Center, called the study “convincing and fascinating.” © 1996-2019 The Washington Post

Keyword: Sleep
Link ID: 25995 - Posted: 03.01.2019

By Gretchen Reynolds A few minutes of brief, intense exercise may be as effective as much lengthier walks or other moderate workouts for incinerating body fat, according to a helpful new review of the effects of exercise on fat loss. The review finds that super-short intervals could even, in some cases, burn more fat than a long walk or jog, but the effort involved needs to be arduous. I have written many times about the health, fitness and brevity benefits of high-intensity interval training, which typically involves a few minutes — or even seconds — of strenuous exertion followed by a period of rest, with the sequence repeated multiple times. Most H.I.I.T. workouts require less than half an hour, from beginning to end (including a warm-up and cool-down), and the strenuous portions of the workout are even briefer. But despite this concision, studies show that interval workouts can improve aerobic fitness, blood sugar control, blood pressure and other measures of health and fitness to the same or a greater extent than standard endurance training, such as brisk walking or jogging, even if it lasts two or three times as long. People being people, though, the most common question I hear about quickie intervals and have asked, on my own behalf, is whether they also will aid in weight control and fat loss. Only a few past studies have directly compared the fat-burning effects of endurance training to those of short interval workouts, however, and their results have been inconsistent. Some indicate that intervals prompt significant fat loss and others that any losses are negligible when compared to the effects of endurance training.

Keyword: Obesity
Link ID: 25994 - Posted: 02.28.2019

Tina Hesman Saey BALTIMORE — Some police dogs may smell fear, and that could be bad news for finding missing people whose genetic makeup leaves them more prone to stress. Trained police dogs couldn’t recognize stressed-out people with a particular version of a gene that’s involved in stress management, geneticist Francesco Sessa reported February 22 at the annual meeting of the American Academy of Forensic Sciences. The dogs had no trouble identifying the men and women volunteers when the people weren’t under stress. The study may help explain why dogs can perform flawlessly in training, but have difficulty tracking people in real-world situations. Sessa, of the University of Foggia in Italy, and colleagues wondered whether fear could change a person’s normal scent and throw off dogs’ ability to find missing people. The researchers also investigated whether people’s genes might make some individuals easier or harder for dogs to pick out of a lineup. Previous studies already had linked different versions of the serotonin transporter gene SLC6A4 to stress management. People with the long version of the gene tend to handle stress better than people with the short version, Sessa said. He and colleagues recruited four volunteers — a man and a woman who each have the long version of the gene and a man and a woman with the short version. Each of the participants wore a scarf for a couple of hours a day to imprint their scent on the garment. Then the researchers brought the volunteers into the lab. In the first session, the volunteers wore a T-shirt and weren’t subjected to any stressors. The team then created two lineups of T-shirts, one with those of the men and another for the women. After sniffing the scarves, two trained police dogs had no trouble identifying any of the volunteers in a lineup of 10 T-shirts. The canine units identified each of the volunteers in three out of three attempts. |© Society for Science & the Public 2000 - 2019

Keyword: Chemical Senses (Smell & Taste); Genes & Behavior
Link ID: 25993 - Posted: 02.28.2019

Sarah DeWeerdt An analysis of four mouse models negates certain assumptions underlying the “signaling imbalance theory,” a popular hypothesis about autism’s origins in the brain. The findings suggest that the imbalance is a compensatory response to other problems in the brain, rather than the underlying cause of autism. The signaling imbalance theory holds that the brains of autistic people have too much excitatory brain activity and not enough inhibitory signals to counteract it. This imbalance then causes neurons to fire too often, the theory goes, and contributes to motor problems, sensory hypersensitivity and other autism traits. This hypothesis, first suggested in 2003, is so popular that it is often cited as fact. The new study questions its underlying assumptions, however. The researchers did find a skewed signaling balance but not the unusually high rate of neuronal firing, or “spikes.” “It’s not as straightforward as the classic hypothesis is worded,” says study leader Dan Feldman, professor of neurobiology at the University of California, Berkeley. “The [signals] are changing in a way that stabilizes brain function rather than creates excess spikes.” Feldman’s team found this pattern in four popular models of autism: mice lacking the genes CNTNAP2 or FMR1, or missing one copy of TSC2 or a region of chromosome 16 called 16p11.2. © 1986 - 2019 The Scientist

Keyword: Autism
Link ID: 25992 - Posted: 02.28.2019