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By ALAN SCHWARZ DELRAY BEACH, Fla. — Three shaky months into recovery from heroin addiction, Dariya Pankova found something to ease her withdrawal. A local nonalcoholic bar sold a brewed beverage that soothed her brain and body much as narcotics had. A perfect solution — before it backfired. Ms. Pankova grew addicted to the beverage itself. She drank more and more, awakened her cravings for the stronger high of heroin, and relapsed. Only during another stay in rehab did Ms. Pankova learn that the drink’s primary ingredient, a Southeast Asian leaf called kratom, affects the brain like an opiate and can be addictive, too. “It’s preying on the weak and the broken,” said Ms. Pankova, 23, a Brooklyn native who received treatment in Delray Beach. “It’s a mind-altering substance, so people like me who are addicts and alcoholics, they think just because it’s legal, it’s fine. It’s a huge epidemic down here, and it’s causing a lot of relapses.” Some users embrace kratom as a natural painkiller and benign substitute for more dangerous substances that, in most states, is legal. But its growing popularity and easy availability are raising concerns among substance abuse experts and government officials who say it is being furtively marketed as a way out of addiction, even though it is itself addictive. Worse, some of those experts say, kratom can lead some addicts back to heroin, which is cheaper and stronger. “It’s a fascinating drug, but we need to know a lot more about it,” said Dr. Edward W. Boyer, a professor of emergency medicine at the University of Massachusetts Medical School and a co-author of several scientific articles on kratom. “Recreationally or to self-treat opioid dependence, beware — potentially you’re at just as much risk” as with an opiate. Concern is particularly high in South Florida, where a rising concentration of drug-treatment providers has coincided with the sprouting of kratom bars. But kratom is now available around the country. © 2016 The New York Times Company

Keyword: Drug Abuse
Link ID: 21747 - Posted: 01.04.2016

By Melinda Wenner Moyer There's a reason your mother told you to look people in the eye when you talk to them: eye contact conveys important social cues. Yet when someone holds your gaze for more than a few seconds, the experience can take on a different tenor. New work elucidates the factors that affect whether we like or loathe locking eyes for a lengthy period. Researchers have long known that eye contact is an important social signal. Our recognition of its import may even be hardwired. One study found that five-day-old babies prefer looking at faces that make direct eye contact compared with faces that have an averted gaze. “Eye contact provides some of the strongest information during a social interaction,” explains James Wirth, a social psychologist now at Ohio State University at Newark, because it conveys details about emotions and intentions. (Lack of eye contact is one of the early signs of autism in infants and toddlers.) The power of eye contact is so great that, according to a 2010 study co-authored by Wirth, if someone avoids your gaze for even a short period, you may feel ostracized. But what determines how we feel about prolonged eye contact? One recent study explored this question. In research presented in May 2015 at the Vision Sciences Society conference, psychologist Alan Johnston and his colleagues at University College London collected information from more than 400 volunteers about their personalities. Then the subjects indicated their comfort level while watching video clips of actors who appeared to be looking directly at them for varying lengths of time. © 2016 Scientific American

Keyword: Autism; Emotions
Link ID: 21746 - Posted: 01.04.2016

By NICHOLAS WADE After decades of disappointingly slow progress, researchers have taken a substantial step toward a possible treatment for Duchenne muscular dystrophy with the help of a powerful new gene-editing technique. Duchenne muscular dystrophy is a progressive muscle-wasting disease that affects boys, putting them in wheelchairs by age 10, followed by an early death from heart failure or breathing difficulties. The disease is caused by defects in a gene that encodes a protein called dystrophin, which is essential for proper muscle function. Because the disease is devastating and incurable, and common for a hereditary illness, it has long been a target for gene therapy, though without success. An alternative treatment, drugs based on chemicals known as antisense oligonucleotides, is in clinical trials. But gene therapy — the idea of curing a genetic disease by inserting the correct gene into damaged cells — is making a comeback. A new technique, known as Crispr-Cas9, lets researchers cut the DNA of chromosomes at selected sites to remove or insert segments. Three research groups, working independently of one another, reported in the journal Science on Thursday that they had used the Crispr-Cas9 technique to treat mice with a defective dystrophin gene. Each group loaded the DNA-cutting system onto a virus that infected the mice’s muscle cells, and excised from the gene a defective stretch of DNA known as an exon. Without the defective exon, the muscle cells made a shortened dystrophin protein that was nonetheless functional, giving all of the mice more strength. The teams were led by Charles A. Gersbach of Duke University, Eric N. Olson of the University of Texas Southwestern Medical Center and Amy J. Wagers of Harvard University. © 2016 The New York Times Company

Keyword: Movement Disorders; Muscles
Link ID: 21745 - Posted: 01.02.2016

By Elizabeth Pennisi Whether foraging for food, caring for young, or defending the nest, the worker castes of carpenter ants toil selflessly for their queen and colony. Now, biologists have figured out how to make some of those worker ants labor even harder, or change their very jobs in ant society, all by making small chemical modifications to their DNA. The finding calls attention to a new source of behavioral flexibility, and drives home the idea that so-called epigenetic modifications can connect genes to the environment, linking nature to nurture. The work is “a pioneering study establishing a causal link between epigenetics and complex social behavior,” says Ehab Abouheif, an evolutionary developmental biologist at McGill University, Montreal, in Canada. “These mechanisms may extend far beyond ants to other organisms with social behavior.” Insect biologists have long debated whether the division of labor in these sophisticated species with castes is driven by colony needs or is innate. Evidence in honey bees had pointed toward a genetic difference between queens and workers. In the past several years, however, work in both honey bees and ants had indicated that epigenetic modifications—changes to DNA other than to its sequence of bases (or DNA “letters”)—influence caste choices, indicating environmental factors can be pivotal. But subsequent research about one type of change, methylation, led to contradictory conclusions. © 2016 American Association for the Advancement of Science.

Keyword: Epigenetics
Link ID: 21744 - Posted: 01.02.2016

By R. Douglas Fields We all heard the warning as kids: “That TV will rot your brain!” You may even find yourself repeating the threat when you see young eyes glued to the tube instead of exploring the real world. The parental scolding dates back to the black-and-white days of I Love Lucy, and today concern is growing amid a flood of video streaming on portable devices. But are young minds really being harmed? With brain imaging, the effects of regular TV viewing on a child's neural circuits are plain to see. Studies suggest watching television for prolonged periods changes the anatomical structure of a child's brain and lowers verbal abilities. Behaviorally, even more detrimental effects may exist: although a cause-and-effect relation is hard to prove, higher rates of antisocial behavior, obesity and mental health problems correlate with hours in front of the set. Now a new study hits the pause button on this line of thinking. The researchers conclude that the entire body of research up to now has overlooked an important confounding variable, heredity, that could call into question the conventional wisdom that TV is bad for the brain. Further study will be needed to evaluate this claim, but the combined evidence suggests we need a more nuanced attitude toward our viewing habits. To understand the argument against television, we should rewind to 2013, when a team ofresearchers at Tohoku University in Japan, led by neuroscientist Hikaru Takeuchi, first published findings from a study in which the brains of 290 children between the ages of five and 18 were imaged. The kids' TV viewing habits, ranging from zero to four hours each day, were also taken into account. © 2016 Scientific American

Keyword: Intelligence; Learning & Memory
Link ID: 21743 - Posted: 01.02.2016

By Ana Swanson Earlier this year, the famous blue-and-black (or white-and-gold) dress captivated the Internet, serving as a reminder that color is truly in the eye of the beholder. The dress was also a lesson in the power of social media, the science of shifting colors, and the fun of optical illusions. Here we present a visual story from February 27 that rounded up some of the best-known optical illusions on the Web. The Internet erupted in an energetic debate yesterday about whether an ugly dress was blue and black or white and gold, with celebrities from Anna Kendrick (white) to Taylor Swift (black) weighing in. (For the record, I’m with Taylor – never a bad camp to be in.) It sounds inane, but the dress question was actually tricky: Some declared themselves firmly in the blue and black camp, only to have the dress appear white and gold when they looked back a few hours later. Wired had the best explanation of the science behind the dress’s shifting colors. When your brain tries to figure out what color something is, it essentially subtracts the lighting and background colors around it, or as the neuroscientist interviewed by Wired says, tries to “discount the chromatic bias of the daylight axis.” This is why you can identify an apple as red whether you see it at noon or at dusk. The dress is on some kind of perceptual boundary, with a pretty even mix of blue, red and green. (Frankly, it’s just a terrible, washed out photo.) So for those who see it as white, your eyes may be subtracting the wrong background and lighting.

Keyword: Vision
Link ID: 21742 - Posted: 01.02.2016

By Mitch Leslie Male mice bequeath an unexpected legacy to their progeny. Two studies published online this week in Science reveal that sperm from the rodents carry pieces of RNAs that alter the metabolism of their offspring. The RNAs spotlighted by the studies normally help synthesize proteins, so the findings point to an unconventional form of inheritance. The results are “exciting and surprising, but not impossible,” says geneticist Joseph Nadeau of the Pacific Northwest Diabetes Research Institute in Seattle, Washington. “Impossible” is exactly how biologists once described so-called epigenetic inheritance, in which something other than a DNA sequence passes a trait between generations. In recent years, however, researchers have found many examples. A male mouse’s diet and stress level, for instance, can tweak offspring metabolism. Researchers are still trying to determine how offspring inherit a father’s metabolic attributes and physiological condition. Some evidence implicates chemical modification of DNA. Other work by neuroscientist Tracy Bale of the University of Pennsylvania Perelman School of Medicine in Philadelphia and colleagues has found that mammalian sperm pack gene-regulating molecules called microRNAs. The new work highlights a different class of RNAs, transfer RNAs (tRNAs). In one study, genomicist Oliver Rando of the University of Massachusetts Medical School in Worcester and colleagues delved into a case of epigenetic inheritance in which the progeny of mice fed a low-protein diet show elevated activity of genes involved in cholesterol and lipid metabolism. When Rando’s group analyzed sperm from the protein-deprived males, they uncovered an increased abundance of fragments from several kinds of tRNAs. The researchers concluded the sperm acquired most of these fragments while passing through the epididymis, a duct from the testicle where the cells mature. © 2016 American Association for the Advancement of Science

Keyword: Epigenetics
Link ID: 21741 - Posted: 01.02.2016

By Nicholas Bakalar Psychotherapy is effective in easing the symptoms of irritable bowel syndrome, researchers have found, even after therapy has ended. Irritable bowel syndrome can cause diarrhea, cramping, fever and sometimes rectal bleeding. The chronic ailment affects up to 11 percent of the population, and there is no cure or completely effective treatment. The study, in Clinical Gastroenterology and Hepatology, used data from 41 clinical trials that included 1,183 people assigned to psychotherapy and 1,107 controls. The approach was usually cognitive therapy, but some studies tested hypnotherapy, mindfulness, behavioral therapy or dynamic psychotherapy. The studies all used questionnaires at the start and end of the treatment, asking about severity and frequency of symptoms. Over all, the researchers found that 12 months after the end of treatment, 75 percent of the treatment group had greater symptom relief than the average member of the control group, although the benefits were modest. “I.B.S. is notoriously difficult to treat,” said the lead author, Kelsey T. Laird, a doctoral candidate at Vanderbilt University, “so the fact that these effects are just as strong six to 12 months later is very exciting — a significant effect, which did not decrease over time.” Whether a given individual will benefit from psychotherapy is still unknown, Ms. Laird said. But, she added, “We do know that this seems to be one of the best treatments out there. So I would recommend it.” © 2016 The New York Times Company

Keyword: Stress
Link ID: 21740 - Posted: 01.02.2016

By KARL OVE KNAUSGAARD I arrived in Tirana, Albania, on a Sunday evening in late August, on a flight from Istanbul. The sun had set while the plane was midflight, and as we landed in the dark, images of fading light still filled my mind. The man next to me, a young, red-haired American wearing a straw hat, asked me if I knew how to get into town from the airport. I shook my head, put the book I had been reading into my backpack, got up, lifted my suitcase out of the overhead compartment and stood waiting in the aisle for the door up ahead to open. That book was the reason I had come. It was called “Do No Harm,” and it was written by the British neurosurgeon Henry Marsh. His job is to slice into the brain, the most complex structure we know of in the universe, where everything that makes us human is contained, and the contrast between the extremely sophisticated and the extremely primitive — all of that work with knives, drills and saws — fascinated me deeply. I had sent Marsh an email, asking if I might meet him in London to watch him operate. He wrote a cordial reply saying that he seldom worked there now, but he was sure something could be arranged. In passing, he mentioned that he would be operating in Albania in August and in Nepal in September, and I asked hesitantly whether I could join him in Albania. Now I was here. Tense and troubled, I stepped out of the door of the airplane, having no idea what lay ahead. I knew as little about Albania as I did about brain surgery. The air was warm and stagnant, the darkness dense. A bus was waiting with its engine running. Most of the passengers were silent, and the few who chatted with one another spoke a language I didn’t know. It struck me that 25 years ago, when this was among the last remaining Communist states in Europe, I would not have been allowed to enter; then, the country was closed to the outside world, almost like North Korea today. Now the immigration officer barely glanced at my passport before stamping it. She dully handed it back to me, and I entered Albania. © 2015 The New York Times Company

Keyword: Consciousness
Link ID: 21739 - Posted: 12.30.2015

Bruce Bower Craig Bryan treats military personnel who struggle with thoughts of ending their own lives, as well as those who’ve survived an actual suicide attempt. But these days he’s fighting an uphill battle. Suicide rates in the United States have been rising, especially among veterans and members of the armed forces. Traditional assumptions about why people kill themselves have not led to effective strategies for suicide prevention, Bryan says. So in recent years psychologists and others have been reconsidering basic beliefs about why people carry out the ultimate act of self-destruction. “There has been an explosion of new thinking about suicide in the past decade,” says Bryan, a clinical psychologist at the University of Utah in Salt Lake City. This shift in focus was inspired by psychologist Thomas Joiner’s introduction in 2005 of the interpersonal theory of suicide. Unlike previous theorists, Joiner, of Florida State University in Tallahassee, treated thinking about suicide and attempting suicide as separate experiences, each with its own explanations and risk factors. Joiner’s approach has inspired much new suicide research by Bryan and others. One line of work suggests that three factors render individuals especially prone to moving from suicidal thoughts to actions: a partly inborn ability to withstand pain, self-hate triggered by extremely distressing experiences and, finally, access to guns or other lethal means. © Society for Science & the Public 2000 - 2015.

Keyword: Depression
Link ID: 21738 - Posted: 12.30.2015

By KEN BELSON When St. Louis Rams quarterback Case Keenum sustained a concussion in a game in Baltimore last month, commentators focused on how he wobbled as he got up and questioned why he was not taken out of the game. Few mentioned that he had slammed his head on the turf. In the rush to reduce head trauma in sports, doctors, researchers, leagues and equipment makers have looked at everything from improving helmets to teaching safer tackling techniques. But one little-explored cause of concussions is the field beneath the feet of the millions of athletes who play football, lacrosse, soccer and other sports. A new report compiled by the Concussion Legacy Foundation called attention to the link between head injuries and poorly maintained fields, especially the growing number of those made of synthetic turf. The foundation urged groundskeepers, athletic directors and sports associations to treat their fields as seriously as other protective sports equipment. “We have no national conversation on the technology underneath an athlete’s feet,” the authors wrote in their report, the Role of Synthetic Turf in Concussion. “Helmet technology is an area of great attention and investment, and surfaces deserve the same attention.” The report, which is based on more than a dozen academic studies, cites research that shows that 15.5 percent of concussions in high school sports occur when players hit their head on a playing surface. Another study found that 10 percent of concussions sustained by high school and college football players came after players hit their head on a field. In the N.F.L., about one in seven concussions occurs when a player’s head strikes a synthetic or grass field. © 2015 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 21737 - Posted: 12.30.2015

By Darryl Fears For male smallmouth bass, sex change is increasingly not an option. In the chemical-laced Chesapeake Bay watershed and in rivers up through New England, it comes with the territory. Based on the latest U.S. Geological Survey on intersex fish, 85 percent of male smallmouth bass in waters in and around national wildlife refuges in the Northeast have developed "characteristics of the opposite sex." That's in addition to 90 percent of the species in some West Virginia waters and 50 percent to 100 percent in the southern stretch of the Potomac River. All of the affected fish had eggs where their testes should be, according to previous studies. Why this is happening remains a mystery, says the lead author of a new study, despite the problem being detected more than a decade ago. “It is not clear what the specific cause of intersex is in these fish,” said Luke Iwanowicz, a USGS research biologist. “This study was designed to identify locations that may warrant further investigation." The strongest suspicion focuses on what is poured down the drains of homes, businesses and farms every day. Scientists are worried that prescription drugs such as birth control and mood-control pharmaceuticals, flushed down toilets, and chemical pesticides such as atrazine, washed off farms by rain, have turned creeks, streams and rivers into chemical soups that disrupt the endocrines of marine life.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 21736 - Posted: 12.30.2015

By Diana Kwon Pupils are a rich source of social information. Although changes in pupil size are automatic and uncontrollable, they can convey interest, arousal, helpful or harmful intentions, and a variety of emotions. According to a new study published in Psychological Science, we even synchronize our pupil size with others—and doing so influences social decisions. Mariska Kret, a psychologist now at the University of Amsterdam in the Netherlands, and her colleagues recruited 69 Dutch university students to take part in an investment game. Each participant decided whether to transfer zero or five euros to a virtual partner after viewing a video of their eyes for four seconds. The invested money is tripled, and the receiver chooses how much to give back to the donor—so subjects had to make quick decisions about how trustworthy each virtual partner seemed. Using an eye tracker, the investigators found that the participants' pupils tended to mimic the changes in the partners' pupils, whether they dilated, constricted or remained static. As expected, subjects were more likely to give more money to partners with dilating pupils, a well-established signal of nonthreatening intentions. The more a subject mirrored the dilating pupils of a partner, the more likely he or she was to invest—but only if they were of the same race. The Caucasian participants trusted Caucasian eyes more than Asian eyes—which suggests that group membership is important when interpreting these subtle signals. © 2015 Scientific American

Keyword: Attention; Emotions
Link ID: 21735 - Posted: 12.30.2015

By Roni Caryn Rabin Melatonin has been shown to be effective in randomized clinical trials — the kind considered the gold standard in medicine — but it may work better for some sleep problems than others. “There is pretty strong evidence it’s effective for jet lag,” said D. Craig Hopp, a program director at the National Center for Complementary and Integrative Health, part of the National Institutes of Health. But “the evidence is more equivocal for chronic things like insomnia.” A 2002 Cochrane review that analyzed 10 randomized trials, most of them comparing oral melatonin to placebo, concluded that melatonin is “remarkably effective in preventing or reducing jet lag.” It not only helped people fall asleep faster and sleep more soundly, but also led to less daytime fatigue and improved general well-being. Eight of the 10 trials found that taking melatonin for several days after arriving at a destination reduced jet lag from flights crossing at least five time zones. In many of the trials, people also took melatonin on the day of the flight or for several days before the trip, usually in the late afternoon or early evening. Once at the destination, melatonin should be taken close to bedtime, aiming for the local hours between 10 p.m. and midnight. Doses of 0.5 milligrams and 5 milligrams were both effective, though people fell asleep faster and slept better with the larger dose. For others with insomnia, melatonin has more modest benefits. A 2013 analysis that looked at 19 randomized controlled trials involving 1,683 subjects determined that on average, melatonin reduced the amount of time it took to fall asleep by seven minutes when compared with placebo and increased total sleep time by eight minutes. © 2015 The New York Times Company

Keyword: Sleep; Biological Rhythms
Link ID: 21734 - Posted: 12.30.2015

Carl Zimmer Throughout the day, a clock ticks inside our bodies. It rouses us in the morning and makes us sleepy at night. It raises and lowers our body temperature and at the right times, and regulates the production of insulin and other hormones. From Our Advertisers The body’s circadian clock even influences our thoughts and feelings. Psychologists have measured some of its effects on the brain by having people take cognitive tests at different times of day. As it turns out, late morning turns out to be the best time to try doing tasks such as mental arithmetic that demand that we hold several pieces of information in mind at once. Later in the afternoon is the time to attempt simpler tasks, like searching for a particular letter in a page of gibberish. Another clue about the clock in our brains comes from people with conditions such as depression and bipolar disorder. People with these disorders often have trouble sleeping at night, or feel groggy during the day. Some people with dementia experience “sundowning,” becoming confused or aggressive at the end of the day. “Sleep and activity cycles are a very big part of psychiatric illnesses,” said Huda Akil, a neuroscientist at the University of Michigan. Yet neuroscientists have struggled to understand exactly how the circadian clock affects our minds. After all, researchers can’t simply pop open a subject’s skull and monitor his brain cells over the course of each day. A few years ago, Dr. Akil and her colleagues came up with an idea for the next best thing. © 2015 The New York Times Company

Keyword: Biological Rhythms; Depression
Link ID: 21733 - Posted: 12.29.2015

Love a sugar hit? Your sweet tooth may hail from an unlikely source: your liver. A hormone made by the organ appears to control how much carbohydrate and sugar we want to eat, and helps slow us down when we are overindulging. The hormone, called FGF21, has already been found to help obese mice lose weight and regain their sensitivity to insulin. A modified form is currently in clinical trials to test whether it has the same effect in people with diabetes. Our bodies break down carbohydrates into sugars such as sucrose, glucose and fructose. Recent genetic studies have suggested that people with altered levels of FGF21 consume more carbohydrates. To find out more, a team co-led by Matthew Potthoff at the University of Iowa observed the eating habits of mice with either abnormally high or low levels of the hormone. They found that mice genetically modified to lack the hormone chose to drink much higher levels of sugar-sweetened drinks than normal mice. Those given an extra dose of the hormone, on the other hand, reduced their sugar intake. The team also showed that the hormone is produced in response to high carbohydrate levels; it then enters the bloodstream, where it sends a signal to the brain to suppress our sugar intake. In people, blood levels of FGF21 triple 24 hours after a spike in blood sugar levels. When monkeys were given the synthetic version of the hormone being tested in clinical trials, they also opted for a diet low in sugar, according to a separate study by Steven Kliewer at the University of Texas Southwestern Medical Center at Dallas and colleagues. The team also found that these monkeys consumed less alcohol than those that weren’t given the compound. © Copyright Reed Business Information Ltd.

Keyword: Obesity; Hormones & Behavior
Link ID: 21732 - Posted: 12.29.2015

By BENEDICT CAREY SAN FRANCISCO — The idea was to go out in an emotional swan dive, a lunge for the afterlife that would stretch his 17-year-old imagination. He settled on a plan and shared the details with a Facebook friend: He would drop DMT, a powerful psychedelic, and then cut his throat. “Everyone was telling me what I could and couldn’t do — doctors, my parents,” said Frank, now a 19-year-old college student. “I was going to hurt myself, to show people, ‘Look, I am still in control of my life.’” And so, in time, he was. Frank, who eight months earlier had received a diagnosis of psychosis, the signature symptom of schizophrenia, and had been in and out of the hospital, gradually learned to take charge of his own recovery, in a new approach to treatment for people experiencing a first psychotic “break” with reality. At a time when lawmakers in Washington are debating large-scale reforms to the mental health care system, analysts are carefully watching a handful of new first-break programs like the one that treated Frank in New York as a way to potentially ease the cycle of hospitalization and lifetime disability that afflict so many mentally ill people. More than two million people in the United States have received a diagnosis of schizophrenia. Most are consigned to whatever treatment is available amid a hodgepodge of programs that often focus on antipsychotic drugs to blunt delusions and paranoia — medicines that can come with side effects so debilitating that many patients go off them and end up in a loop of hospitalization and despair. But over the past several years, a number of states have set up programs with a different approach, emphasizing supportive services, like sustained one-on-one therapy, school and work assistance, and family education, as well as medication. The therapists work to engage each patient as an equal partner in decisions — including about medication dosage, to make it as tolerable as possible. © 2015 The New York Times Company

Keyword: Schizophrenia
Link ID: 21731 - Posted: 12.29.2015

By Gary Stix A lingering question asked by neuroscientists has to do with what, if anything, makes the male and female brain distinctive, whether in mice or (wo)men. There is still no concise answer. The best evidence from the most recent research suggests that both males and females share the same neural circuitry, but use it differently. Catherine Dulac, a professor of molecular and cellular biology at Harvard, and investigator at the Howard Hughes medical Institute, is a pioneer in exploring these questions. I talked to her briefly about her research, which also extends far beyond just the neurobiology of gender. Can you tell me in broad overview about what you study? I'm interested in understanding how the brain engages in instinctive social behaviors. There are a lot of instinctive behaviors such as eating and sleeping that are essential in animals and humans, but social behavior is a very distinctive and particularly interesting set of instinctive behaviors that we would like to understand at the neuronal level. What we would like to understand in mechanistic terms is how does an individual recognize other animals of its own species, for example how does an animal identifies a male, a female, or an infant, how does the brain processes these signals in order to trigger appropriate social behaviors such as mating, aggression or parenting. Can you tell me a little bit about your work of the last few years that relates to gender identification? © 2015 Scientific American

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 21730 - Posted: 12.29.2015

By Katrina Schwartz It has become a cultural cliché that raising adolescents is the most difficult part of parenting. It’s common to joke that when kids are in their teens they are sullen, uncommunicative, more interested in their phones than in their parents and generally hard to take. But this negative trope about adolescents misses the incredible opportunity to positively shape a kid’s brain and future life course during this period of development. “[Adolescence is] a stage of life when we can really thrive, but we need to take advantage of the opportunity,” said Temple University neuroscientist Laurence Steinberg at a Learning and the Brain conference in Boston. Steinberg has spent his career studying how the adolescent brain develops and believes there is a fundamental disconnect between the popular characterizations of adolescents and what’s really going on in their brains. Because the brain is still developing during adolescence, it has incredible plasticity. It’s akin to the first five years of life, when a child’s brain is growing and developing new pathways all the time in response to experiences. Adult brains are somewhat plastic as well — otherwise they wouldn’t be able to learn new things — but “brain plasticity in adulthood involves minor changes to existing circuits, not the wholesale development of new ones or elimination of others,” Steinberg said. Adolescence is the last time in a person’s life that the brain can be so dramatically overhauled. © 2015 KQED Inc.

Keyword: Development of the Brain; Sexual Behavior
Link ID: 21729 - Posted: 12.29.2015

By Karen Weintraub Mild cognitive impairment, or M.C.I., is not a disease in itself. Rather, it is a clinical description based on performance on a test of memory and thinking skills. Depending on its cause, mild cognitive impairment is potentially reversible. Poor performance on a cognitive test could be caused by certain medications, sleep apnea, depression or other problems, said Dr. Alvaro Pascual-Leone, a professor of neurology at Harvard Medical School and Beth Israel Deaconess Medical Center. In those cases, when the underlying disease is treated, cognitive abilities can bounce back. But in about half of people with M.C.I. – doctors are not sure of the exact number — memory problems are the first sign of impending Alzheimer’s disease. If M.C.I. progresses to Alzheimer’s, there is no recovery. Alzheimer’s is marked by an inexorable decline that is always fatal, although the path from the first signs of cognitive impairment to death may take three to 15 years, said Dr. David Knopman, a professor of neurology at the Mayo Clinic in Rochester, Minn. As many as 20 percent to 30 percent of those with M.C.I. who score below but near the cutoff for normal can cross back above in a subsequent cognitive test – perhaps because they are having a better day, he said. But someone whose score is borderline is at higher risk of developing Alzheimer’s than someone who scores higher, said Dr. Knopman, also vice chair of the medical and scientific advisory council of the Alzheimer’s Association. Doctors may be hesitant to label someone with early Alzheimer’s, which can be difficult to diagnose in the early stages, so they often call it mild cognitive impairment instead, said Dr. John C. Morris, a professor of neurology and the director of the Knight Alzheimer's Disease Research Center at Washington University School of Medicine in St. Louis. © 2015 The New York Times Company

Keyword: Alzheimers; Learning & Memory
Link ID: 21728 - Posted: 12.29.2015