Links for Keyword: Development of the Brain

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By Benedict Carey A generation ago, parents worried about the effects of TV; before that, it was radio. Now, the concern is “screen time,” a catchall term for the amount of time that children, especially preteens and teenagers, spend interacting with TVs, computers, smartphones, digital pads, and video games. This age group draws particular attention because screen immersion rises sharply during adolescence, and because brain development accelerates then, too, as neural networks are pruned and consolidated in the transition to adulthood. On Sunday evening, CBS’s “60 Minutes” reported on early results from the A.B.C.D. Study (for Adolescent Brain Cognitive Development), a $300 million project financed by the National Institutes of Health. The study aims to reveal how brain development is affected by a range of experiences, including substance use, concussions, and screen time. As part of an exposé on screen time, “60 Minutes” reported that heavy screen use was associated with lower scores on some aptitude tests, and to accelerated “cortical thinning" — a natural process — in some children. But the data is preliminary, and it’s unclear whether the effects are lasting or even meaningful. Does screen addiction change the brain? Yes, but so does every other activity that children engage in: sleep, homework, playing soccer, arguing, growing up in poverty, reading, vaping behind the school. The adolescent brain continually changes, or “rewires” itself, in response to daily experience, and that adaptation continues into the early to mid 20s. What scientists want to learn is whether screen time, at some threshold, causes any measurable differences in adolescent brain structure or function, and whether those differences are meaningful. Do they cause attention deficits, mood problems, or delays in reading or problem-solving ability? © 2018 The New York Times Company

Related chapters from BN8e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 13: Memory, Learning, and Development
Link ID: 25772 - Posted: 12.11.2018

Infections May Raise The Risk Of Mental Illness In Children

Rhitu Chatterjee Researchers have traced a connection between some infections and mental illnesses like schizophrenia, depression and bipolar disorder. New research from Denmark bolsters that connection. The study, published Thursday in JAMA Psychiatry, shows that a wide variety of infections, even common ones like bronchitis, are linked to a higher risk of many mental illnesses in children and adolescents. The findings support the idea that infections affect mental health, possibly by influencing the immune system. "This idea that activation of the body's immune inflammatory system as a causative factor in ... select mental illnesses is one that has really caught on," says Dr. Roger McIntyre, a professor of psychology and pharmacology at the University of Toronto, who wasn't involved in the study. "This study adds to that generally, but builds the case further in a compelling way." In the new study, the researchers gathered data on hospitalizations and prescription medications for the 1.1 million children born in Denmark between Jan. 1, 1995, and June 30, 2012. "We could follow individuals from birth, so there was no missing information during the study period," says Dr. Ole Köhler-Forsberg of Aarhus University Hospital, a neuroscientist and one of the authors of the study. Köhler-Forsberg and his colleagues used two national registries — one to get data on hospitalizations because of severe infections like pneumonia and another for data on antimicrobial or antiparasitic medications prescribed to children for less severe infections. "Most of them are those infections that you and I and all others have experienced," says Köhler-Forsberg. © 2018 npr

Related chapters from BN8e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 25756 - Posted: 12.06.2018

Lab-grown ‘mini brains’ produce electrical patterns that resemble those of premature babies

Sara Reardon ‘Mini brains’ grown in a dish have spontaneously produced human-like brain waves for the first time — and the electrical patterns look similar to those seen in premature babies. The advancement could help scientists to study early brain development. Research in this area has been slow, partly because it is difficult to obtain fetal-tissue samples for analysis and nearly impossible to examine a fetus in utero. Many researchers are excited about the promise of these ‘organoids’, which, when grown as 3D cultures, can develop some of the complex structures seen in brains. But the technology also raises questions about the ethics of creating miniature organs that could develop consciousness. A team of researchers led by neuroscientist Alysson Muotri of the University of California, San Diego, coaxed human stem cells to form tissue from the cortex — a brain region that controls cognition and interprets sensory information. They grew hundreds of brain organoids in culture for 10 months, and tested individual cells to confirm that they expressed the same collection of genes seen in typical developing human brains1. The group presented the work at the Society for Neuroscience meeting in San Diego this month. Muotri and his colleagues continuously recorded electrical patterns, or electroencephalogram (EEG) activity, across the surface of the mini brains. By six months, the organoids were firing at a higher rate than other brain organoids previously created, which surprised the team. © 2018 Springer Nature Limited.

What makes us? Nature or nurture? The DNA debate comes back to life

by Robin McKie Robert Shafran’s first inkling that his life would soon be turned on its head occurred on his first day at college in upstate New York in 1980. His fellow students greeted him like a long-lost friend. “Guys slapped me on the back, girls hugged and kissed me,” he recalls. Yet Robert had never set foot inside Sullivan County Community College until that day. Another student, Eddy Galland, who had studied at the college the previous year, was the cause of the confusion, it transpired. Eddy was his spitting image, said classmates. Robert was intrigued and went to Eddy’s home to confront him. Sign up for Lab Notes - the Guardian's weekly science update Read more “As I reached out to knock on the door, it opened – and there I am,” says Robert, recalling his first meeting with Eddy in the forthcoming documentary Three Identical Strangers. The two young men had the same facial features, the same heavy build, the same dark complexions, the same mops of black curly hair – and the same birthday: 12 July 1961. They were identical twins, a fact swiftly confirmed from hospital records. Each knew he had been adopted but neither was aware he had a twin. Their story made headlines across the US. One reader – David Kellman, a student at a different college – was particularly interested. Robert and Eddy also looked astonishingly like him. So he contacted Eddy’s adoptive mother, who was stunned to come across, in only a few weeks, two young men who were identical in appearance to her son. “My God, they are coming out of the woodwork,” she complained. © 2018 Guardian News and Media Limited

Related chapters from BN8e: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 25673 - Posted: 11.12.2018

Fetal Marijuana Exposure Stunts Rat Cognitive Performance

Jef Akst When presented with two levers, laboratory rats that were exposed to cannabis in utero were able to learn to push the one below the lightbulb that lit up. But the animals struggled to adjust their strategy when the rules of the game changed, for example, when they received a sugar reward when they pushed only the left or right lever regardless of the lightbulb. Rats born to mothers who had not inhaled cannabis were better able to learn the new strategy. The results, presented yesterday (November 4) at the annual Society for Neuroscience conference, are “indicative of an inability to acquire and maintain a new strategy” following fetal cannabis exposure, says Hayden Wright, a PhD student in Ryan McLaughlin’s lab at Washington State University. Understanding such effects is critical as marijuana becomes legalized across the US, he adds. “As states allow more access, there has been an increase in self-reported cannabis use during pregnancy.” Most studies of cannabis exposure in rodents have used injections of purified THC, the psychoactive ingredient in the drug, and the results are therefore hard to translate to humans who smoke marijuana, which contains more than 100 other active cannabinoids, Wright says. So the McLaughlin lab developed an experimental system that vaporizes cannabis extract into a glass enclosure where rats can be kept for variable periods of time. For the current study, the researchers placed female rats in the chamber for two one-hour sessions per day throughout mating and gestation. During these sessions, the animals were exposed to cannabis-free vapor or vapor that contained high or low levels of the drug. The offspring of these rats were then tested for their ability to learn a simple lever-pressing task at two-months old. © 1986 - 2018 The Scientist

A ‘don’t eat me’ immune signal protects neuronal connections

Serge Rivest The signals transmitted between neurons through synaptic connections are responsible for most, if not all, brain functions, from learning to decision-making. During brain development, synapses that are stimulated less often than others are eliminated through a process called pruning, whereas those that are highly stimulated are retained. This refines the brain’s ability to respond to stimuli and environmental cues. Microglia, the brain’s innate immune cells, have a key role in pruning — they engulf and digest synapses through a process called phagocytosis. But the mechanism that determines which synapses they avoid has been unclear. Writing in Neuron, Lehrman et al.1 describe a ‘don’t eat me’ signal, involving a protein called cluster of differentiation 47 (CD47), that prevents inappropriate synaptic pruning by microglia. About a decade ago, it was shown that synapses requiring elimination send an ‘eat me’ signal to microglia2 (Fig. 1a). This signal involves the proteins C1q and CR3, which are part of the complement cascade — a complex series of interactions that is best known for activating cells of the innate immune system to eliminate disease-causing organisms and damaged cells. ‘Don’t eat me’ signals act to limit the effects of ‘eat me’ signals in the immune system, but it was not known whether the same process occurs during synaptic pruning in the developing brain. CD47 is a cell-surface protein that has many immune functions, including acting as a ‘don’t eat me’ signal for macrophages3, microglia’s sister cells, which exist outside the brain. Lehrman et al. analysed whether CD47 is expressed in the dorsal lateral geniculate nucleus (dLGN), a region of the brain involved in vision. This region receives inputs from neurons called retinal ganglion cells (RGCs) that originate in the retina. The authors demonstrated in mice that, at five days after birth, synapses from RGCs to other neurons in the dLGN are being pruned at high levels. © 2018 Springer Nature Limited

Related chapters from BN8e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 11: Emotions, Aggression, and Stress
Link ID: 25629 - Posted: 10.31.2018

Surgeons repair babies' spinal cords in the womb in UK first

Weeks before they took their first breaths, two babies had their spinal cords delicately repaired by surgeons in the first operations of their kind in the UK. The spina bifida surgeries were successfully performed by a team at University College hospital in London this summer on two babies while they were still in the womb. Spina bifida is usually treated after birth, but research shows repairing the spine earlier can stop the loss of spinal fluid and lead to better long-term health and mobility outcomes. A 30-strong team carried out the two operations, coordinated by the UCL professor Anna David, who had worked for three years to bring the procedure to patients in the UK. She said mothers previously had to travel to the US, Belgium or Switzerland. “It’s fantastic. Women now don’t have to travel out of the UK,” David said. “They can have their family with them. There are less expenses. So all good things.” Advertisement The surgery team from University College London hospitals (UCLH) and Great Ormond Street hospital travelled to Belgium to train at a facility in Leuven, where more than 40 of the operations have been carried out. Spina bifida is a condition that develops during pregnancy when the bones of the spine do not form properly, creating a gap that leaves the spinal cord unprotected. It can cause a baby’s spinal fluid to leak and affect brain development, potentially leading to long-term health and mobility problems. © 2018 Guardian News and Media Limited

Leaping from specialists to ERs fails to solve this young boy’s odd ailments

By Sandra G. Boodman Ever since he was a toddler, Michael had been beset by an array of medical problems that doctors couldn’t explain. Severe leg pain came first. That was followed a few years later by recurrent, sometimes severe, stomachaches. Later, the little boy developed a wracking cough, followed by trouble breathing. In fifth grade, after he fell and smacked his tailbone, he was in so much pain he wound up in a wheelchair. His worried parents took him to four emergency rooms and an array of Washington-area specialists, among them orthopedists, neurologists, pediatricians and a gastroenterologist. Yet virtually every test failed to uncover a problem. It would take a seasoned pediatrician to pull together the disparate elements of the 10-year-old’s medical history and make an unexpected diagnosis that would prove to be a turning point for the boy and his family. Three years later, Michael, now 14 and a freshman in high school, seems to have moved beyond the disorder that dominated his first decade. His father said he believes his son’s illness resulted from “a perfect storm” of factors. He would have preferred that the doctors who saw Michael had spoken “a little more freely about their guesses” and had provided more guidance. To protect Michael’s privacy, his parents requested that he and they be identified by their middle names. When he was nearly 2, Michael, who had been previously healthy, began limping and then stopped walking. His pediatrician found no obvious explanation and sent him to a pediatric neurologist, who ordered an extensive work-up, including scans and blood tests. © 1996-2018 The Washington Post

Related chapters from BN8e: Chapter 16: Psychopathology: Biological Basis of Behavior Disorders; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 12: Psychopathology: The Biology of Behavioral Disorders; Chapter 13: Memory, Learning, and Development
Link ID: 25598 - Posted: 10.22.2018

A tailormade drug developed in record time may save girl from fatal brain disease

By Jocelyn KaiserO For years, a Colorado couple searched for an explanation for why their bright, active little girl was having increasing trouble walking, speaking, and seeing. In December 2016, Julia Vitarello and Alek Makovec learned that 6-year-old Mila Makovec almost certainly had Batten disease, an inherited and fatal neurodegenerative disorder. Now, in a stunning illustration of personalized genomic medicine, Mila is receiving a drug tailored to her particular disease-causing DNA mutation—and it appears to have halted the condition’s progression. Today at the annual meeting of The American Society of Human Genetics in San Diego, California, researchers told the story of how in less than a year, they went from sequencing Mila’s genome to giving her a synthetic RNA molecule that helps her cells ignore her genetic flaw and make a needed protein. The same steps could help some other patients with diseases caused by unique mutations in a single gene, they said. “It’s very exciting,” says gene therapy researcher Steven Gray of the University of Texas Southwestern Medical Center in Houston, who wasn’t involved in the research. “There couldn’t be a stronger example of how personalized medicine might work in practice.” Batten disease afflicts an estimated two to four in 100,000 births in the United States. Patients have problems with lysosomes, enzyme-filled sacs within cells that clear waste molecules. Without properly working lysosomes, waste builds up and kills neural cells, causing brain damage and death by adolescence. © 2018 American Association for the Advancement of Science

Why is a remote Colombian town a hot spot of an inherited intellectual disability?

By Hannah Furfaro, RICAURTE, COLOMBIA—It's late afternoon in this tiny town tucked into the Colombian Andes, when Mercedes Triviño, 82, lights the wood stove to start to prepare dinner. Smoke fills the two-bedroom home she shares with six of her adult children. Francia, 38, one of the youngest, is the family's primary breadwinner. She brings home 28,000 Colombian pesos (roughly $10) a day harvesting papayas in the fields just outside town. "Really, what I earn is just enough for eating and nothing else," she says. Four of her siblings have fragile X syndrome, a genetic condition that causes intellectual disability, physical abnormalities, and often autism. Jair, 57, works alongside Francia when he can. Hector, 45, is also somewhat able to care for himself. Victor, 55, and Joanna, 35—who has both fragile X and Down syndrome—are less independent. As Mercedes serves coffee on this July afternoon, sweetening it with a hefty dose of sugar and offering her best cups to her guests, she talks about the condition that dominates the lives of her family and many others here. Her niece, Patricia, 48, who lives a few blocks away, cares for two adult sons and a nephew with fragile X. More distant kin in town, the Quinteros, also have grown children with the condition. Other neighbors are adults with fragile X who have no caretaker and look after one another. © 2018 American Association for the Advancement of Science

See these dazzling images of a growing mouse embryo

Cassie Martin A new microscope is giving researchers an unprecedented view of how mammals are built, cell by cell. Light sheet microscopes use ultrathin laser beams to illuminate sections of a specimen while cameras record those lit-up sections. Previous iterations of the device have captured detailed portraits of living zebra fish and fruit fly embryos as they develop. Kate McDole, a developmental biologist at Howard Hughes Medical Institute’s Janelia Research Campus in Ashburn, Va., and colleagues used a new-and-improved version to monitor the development of a larger, more complex organism: the mouse. Algorithms in the microscope tracked six-day-old mouse embryos in real time over roughly two days, keeping the device focused on the cell clusters as they grew. A suite of computer programs used the data — about a million images per embryo — to map the life history of each embryo’s every cell, the team reports October 11 in Cell. The result: dazzling views of mouse organs taking shape. As an embryo rapidly expands in size, the gut starts to form when part of the embryo collapses into a craterlike hole. And a structure that eventually forms the brain and spinal cord, called a neural tube, appears like a comet shooting across the night sky. Researchers also captured the first beats of heart cells. “These are processes no one has been able to watch before,” McDole says. Seeing the gut form in minutes was stunning. “We never expected it to be that fast or that dramatic. It’s not like you can Google these things.” |© Society for Science & the Public 2000 - 2018

Survey raises worries about how screen time affects kids’ brains

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

Growing Brains in Lab

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

Marijuana use among pregnant women is rising, and so are concerns

Laura Sanders I’m relatively new to Oregon, but one of the ways I know I’m starting to settle in is my ability to recognize marijuana shops. Some are easy. But others, with names like The Agrestic and Mr. Nice Guy, are a little trickier to identify for someone who hasn’t spent much time in a state that has legalized marijuana. A growing number of states have legalized both medical and recreational marijuana. At the same time, women who are pregnant or breastfeeding are using the drug in increasing numbers. A 2017 JAMA study described both survey results and urine tests of nearly 280,000 pregnant women in Northern California, where medical marijuana was legalized in 1996. The study showed that in 2009, about 4 percent of the women tested used marijuana. In 2016, about 7 percent of women did. Those California numbers may be even higher now, since recreational marijuana became legal there this year. Some of those numbers may be due in part to women using marijuana to treat their morning sickness, a more recent study by some of the same researchers suggests. Their report, published August 20 in JAMA Internal Medicine, found that pregnant women with severe nausea and vomiting were 3.8 times more likely to use marijuana than pregnant women without morning sickness. So some pregnant women are definitely using the drug, and exposing their fetuses to it, too. Ingredients in marijuana are known to make their way to fetuses by crossing the placenta during pregnancy (and by entering breast milk after the baby is born). But what actually happens when those marijuana compounds arrive? © Society for Science and the Public

The Big Myth About Teenage Anxiety

By Richard A. Friedman We hear a lot these days that modern digital technology is rewiring the brains of our teenagers, making them anxious, worried and unable to focus. Don’t panic; things are really not this dire. Despite news reports to the contrary, there is little evidence of an epidemic of anxiety disorders in teenagers. This is for the simple reason that the last comprehensive and representative survey of psychiatric disorders among American youth was conducted more than a decade ago, according to Kathleen Ries Merikangas, chief of the Genetic Epidemiology Research Branch at the National Institute of Mental Health. There are a few surveys reporting increased anxiety in adolescents, but these are based on self-reported measures — from kids or their parents — which tend to overestimate the rates of disorders because they detect mild symptoms, not clinically significant syndromes. So what’s behind the idea that teenagers are increasingly worried and nervous? One possibility is that these stories are the leading edge of a wave of anxiety disorders that has yet to be captured in epidemiological surveys. Or maybe anxiety rates have risen, but only in the select demographic groups — the privileged ones — that receive a lot of media attention. But it’s more likely that the epidemic is simply a myth. The more interesting question is why it has been so widely accepted as fact. One reason, I believe, is that parents have bought into the idea that digital technology — smartphones, video games and the like — are neurobiologically and psychologically toxic. If you believe this, it seems intuitive that the generations growing up with these ubiquitous technologies are destined to suffer from psychological problems. But this dubious notion comes from a handful of studies with serious limitations. © 2018 The New York Times Company

Scientists Are Retooling Bacteria to Cure Disease

By Carl Zimmer In a study carried out over the summer, a group of volunteers drank a white, peppermint-ish concoction laced with billions of bacteria. The microbes had been engineered to break down a naturally occurring toxin in the blood. The vast majority of us can do this without any help. But for those who cannot, these microbes may someday become a living medicine. The trial marks an important milestone in a promising scientific field known as synthetic biology. Two decades ago, researchers started to tinker with living things the way engineers tinker with electronics. They took advantage of the fact that genes typically don’t work in isolation. Instead, many genes work together, activating and deactivating one another. Synthetic biologists manipulated these communications, creating cells that respond to new signals or respond in new ways. Until now, the biggest impact has been industrial. Companies are using engineered bacteria as miniature factories, assembling complex molecules like antibiotics or compounds used to make clothing. In recent years, though, a number of research teams have turned their attention inward. They want to use synthetic biology to fashion microbes that enter our bodies and treat us from the inside. The bacterial concoction that volunteers drank this summer — tested by the company Synlogic — may become the first synthetic biology-based medical treatment to gain approval by the Food and Drug Administration. The bacteria are designed to treat a rare inherited disease called phenylketonuria, or PKU. People with the condition must avoid dietary protein in foods such as meat and cheese, because their bodies cannot break down a byproduct, an amino acid called phenylalanine. As phenylalanine builds up in the blood, it can damage neurons in the brain, leading to delayed development, intellectual disability and psychiatric disorders. The traditional treatment for PKU is a strict low-protein diet, accompanied by shakes loaded with nutritional supplements. © 2018 The New York Times Company

What Twins Can Teach Us About Nature vs. Nurture

By Jane E. Brody The day my identical twin boys were delivered by an emergency cesarean, I noticed a behavioral difference. Twin A, who had been pushed against an unyielding pelvis for several hours, spent most of his first day alert and looking around, while Twin B, who had been spared this pre-birth stress, slept calmly like a typical newborn. My husband and I did our best to treat them equally, but Twin A was more of a challenge to hold — we called him “our lobster baby” — while Twin B was easily cuddled. As the boys developed, we saw other differences. Twin B rehearsed all the ambulatory milestones — crawling, walking, cycling, skating, etc. — while his twin watched, then copied the skill when it was mastered. Although they shared all their genes and grew up with the same adoring parents, clearly there were differences in these boys that had been influenced by other factors in their environment, both prenatal and postnatal. The relative importance of nature and nurture to how a child develops has been debated by philosophers and psychologists for centuries, and has had strong — and sometimes misguided — influences on public policy. The well-intentioned Head Start program, for example, was designed to give children from deprived environments an academic leg up. But it might have been more effective to teach their caregivers parenting and nurturing skills, as well as how to enrich the children’s environment and resist bad influences. Children learn from what they see around them, and if what they mainly experience is violence, abuse, truancy and no expectations for success, their chances for a wholesome future are compromised from the start. As my son Erik Engquist, a fellow journalist who was Twin A, put it: “Genes define your potential, but your environment largely determines how you turn out. The few who escape negative influences are outliers.” © 2018 The New York Times Company

Sex, Drugs and Self-Control

By Kerri Smith, Cole Skinner was hanging from a wall above an abandoned quarry when he heard a car pull up. He and his friends bolted, racing along a narrow path on the quarry’s edge and hopping over a barbed-wire fence to exit the grounds. The chase is part of the fun for Skinner and his friend Alex McCallum-Toppin, both 15 and pupils at a school in Faringdon, UK. The two say that they seek out places such as construction sites and disused buildings—not to get into trouble, but to explore. There are also bragging rights to be earned. “It’s just something you can say: ‘Yeah, I’ve been in an abandoned quarry’,” says McCallum-Toppin. “You can talk about it with your friends.” Science has often looked at risk-taking among adolescents as a monolithic problem for parents and the public to manage or endure. When Eva Telzer, a neuroscientist at the University of North Carolina in Chapel Hill, asks family, friends, undergraduates or researchers in related fields about their perception of teenagers, “there’s almost never anything positive,” she says. “It’s a pervasive stereotype.” But how Alex and Cole dabble with risk—considering its social value alongside other pros and cons—is in keeping with a more complex picture emerging from neuroscience. Adolescent behaviour goes beyond impetuous rebellion or uncontrollable hormones, says Adriana Galván, a neuroscientist at the University of California, Los Angeles. “How we define risk-taking is going through a shift.” © 2018 Scientific American

‘Teens get a bad rap’: the neuroscientist championing moody adolescents

Decca Aitkenhead Annual media coverage of August’s exam results has traditionally conformed to an unwritten rule that all photos must show euphoric teenagers celebrating multiple A*s. This year, the images may tell a different story. Radical reforms to GCSEs are widely predicted to produce disappointment, and many teenagers are bracing themselves for the worst. Parents may be unsympathetic, however, if their 15- or 16-year-old spent the exam year ignoring all their wise advice to revise, and instead lay in bed until lunchtime and partied all night with friends. Even if the exam results turn out to be good, many will wonder why their teenager took so many risks with their future. Sarah-Jayne Blakemore looks barely older than a teenager herself. The award-winning professor of cognitive neuroscience at University College London is, in fact, 44 and has made the study of the adolescent brain her life’s work. She has been critical of the very existence of GCSEs, arguing that they impose “enormous stress” on teenagers at a time when their brains are going through huge change. “Until about 15 or 20 years ago,” she says, “we just didn’t know that the brain develops at all within the teenage years.” Until then, it was assumed that teenage behaviour was almost entirely down to hormonal changes in puberty, but brain scans and psychological experiments have now found that adolescence is a critical period of neurological change, much of which is responsible for the unique characteristics of adolescent behaviour. Far from being a defective or inferior version of an adult brain, the adolescent mind is both unique and – to Blakemore – beautiful. “Teenagers,” she says tenderly, “are brilliant.” © 2018 Guardian News and Media Limited

A 12-year-old had one-sixth of his brain removed. He feels ‘perfectly normal.’

by Lindsey Bever It was a solution no parent wants to hear: To get rid of a brain tumor and stop their young son's seizures, surgeons would need to cut out one-sixth of his brain. But for Tanner Collins, it was the best option. A slow-growing tumor was causing sometimes-daily seizures, and medications commonly used to treat them did not seem to be working, his father said. But removing a portion of his brain was no doubt risky. That region — the right occipital and posterior temporal lobes — is important for facial recognition, and, without it, Tanner's parents wondered if he would recognize them. Tanner, who was 6 at the time, underwent surgery at the University of Pittsburgh Medical Center's Children's Hospital. Although his brain has had to work to adapt since then, he's had no major problems. Other than some visual impairment, Tanner, now 12, said he's “perfectly fine.” “As far as I’m concerned, I’m a perfectly normal 12-year-old boy,” Tanner said. Tanner's case was published Tuesday in the scientific journal Cell Reports, explaining how the 12-year-old's brain learned to adapt after a part largely responsible for visual processing was taken out. Marlene Behrmann, a cognitive neuroscientist and lead author of the paper, said Tanner was one of the first pediatric patients studied over the past several years in her laboratory at Carnegie Mellon University to determine the extent to which a child's brain can reorganize itself after certain sections are surgically removed. In Tanner's case, she said, surgeons took out his right occipital and posterior temporal lobes, which made up about one-third of the right hemisphere of his brain. © 1996-2018 The Washington Post

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Links for Keyword: Development of the Brain