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The Hidden Cost of Gold: Birth Defects and Brain Damage

By Richard C. Paddock CIDAHU, Indonesia — Thousands of children with crippling birth defects. Half a million people poisoned. A toxic chemical found in the food supply. Accusations of a government cover-up and police officers on the take. This is the legacy of Indonesia’s mercury trade, a business intertwined with the lucrative and illegal production of gold. More than a hundred nations have joined a global campaign to reduce the international trade in mercury, an element so toxic there is “no known safe level of exposure,” according to health experts. But that effort has backfired in Indonesia, where illicit backyard manufacturers have sprung up to supply wildcat miners and replace mercury that was previously imported from abroad. Now, Indonesia produces so much black-market mercury that it has become a major global supplier, surreptitiously shipping thousands of tons to other parts of the world. Much of the mercury is destined for use in gold mining in Africa and Asia, passing through hubs such as Dubai and Singapore, according to court records — and the trade has deadly consequences. “It is a public health crisis,” said Yuyun Ismawati, a co-founder of an Indonesian environmental group, Nexus3 Foundation, and a recipient of the 2009 Goldman Environmental Prize. She has called for a worldwide ban on using mercury in gold mining. Mercury can be highly dangerous as it accumulates up the food chain, causing a wide range of disorders, including birth defects, neurological problems and even death. ImageA small mine on Sumbawa. Miners often dig for ore on land without permission or government permits. Today, despite the risks, small-scale miners using mercury operate in about 80 countries in Asia, Africa and the Americas. They produce up to 25 percent of all gold sold. © 2019 The New York Times Company

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: 26809 - Posted: 11.11.2019

Using both marijuana and alcohol during early pregnancy may increase the likelihood of disrupting fe

New preclinical research reported in animal models shows that exposure to compounds found in marijuana called cannabinoids (CBs), which includes cannabidiol (CBD) and tetrahydrocannabinol (THC), during early pregnancy can cause malformations in the developing embryo. The research also demonstrated that co-exposure to CBs and alcohol increased the likelihood of birth defects involving the face and brain. The study, funded by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health, was published in Scientific Reports. “Prenatal alcohol exposure is a leading preventable cause of birth defects and neurodevelopmental abnormalities in the United States,” said NIAAA Director, George F. Koob, Ph.D. “Since marijuana and alcohol are frequently used simultaneously, the combined effects of cannabinoids and alcohol are worrisome as well as the dangers of either substance alone.” The detrimental effects of prenatal alcohol exposure on human development are well known and include an array of lifelong physical, cognitive, and behavioral problems collectively called fetal alcohol spectrum disorders (FASD). Alcohol can disrupt fetal development at any stage during pregnancy, even the earliest stages before a woman knows she is pregnant. The effects of marijuana exposure during pregnancy and the combined effect of alcohol and marijuana are less known. In the study, scientists led by Scott Parnell, Ph.D., at the Bowles Center for Alcohol Studies at the University of North Carolina in Chapel Hill, administered a variety of CBs alone and in combination with alcohol in varying amounts to mice on day eight of pregnancy, which is similar to the third and fourth weeks of pregnancy in humans. The CBD amounts administered were within what is considered a therapeutic range for several medical conditions in humans. The THC concentration administered was similar to levels reached by a person smoking marijuana.

Study offers fresh hope to premature babies with brain injuries

Nicola Davis A potential route to reducing brain injury in premature babies has been found, say researchers who have discovered a way to tackle overactive immune cells in the brain. Microglia are a type of immune cell that play an important part in the building of a baby’s brain. However, if these cells go into overdrive as a result of inflammation – often because of a bacterial infection of the foetal membranes, a maternal infection or even sepsis after delivery of the baby – they can cause harm to the child’s brain. In particular, they can damage white matter, reducing the degree to which neurons are insulated and thereby affecting connectivity in the brain. It is thought that of the 15 million infants born before 37 weeks every year, up to 9 million are left with lifelong harm to the brain, sometimes resulting in conditions such as epilepsy or cerebral palsy. Now researchers say they have found a signalling pathway in these immune cells that is behind their transformation. “We have actually identified the immune switch that turns these immune cells in the developing brain from being helpful in building a brain and taking care of the brain to causing damage,” said Dr Bobbi Fleiss from RMIT University in Melbourne, Australia, a co-author of the study. What is more, the researchers say, it might even be possible to intervene and turn rogue microglia back into helpful workhorses. Writing in the journal Brain, Fleiss and colleagues reported how they took mouse pups just after birth and injected them with proteins that mimic an infection in the mother or foetus, inducing the transformation of microglia from helpful to harmful. © 2019 Guardian News & Media 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: 26785 - Posted: 11.02.2019

Lab-grown organoids are more stressed-out than actual brain cells

By Laura Sanders CHICAGO — Brain cells grown into clumps in flasks are totally stressed-out and confused. Cells in these clumps have ambiguous identities and make more stress molecules than cells taken directly from human brains, researchers reported October 22 at the annual meeting of the Society for Neuroscience. These cellular clumps are grown using stem cells made from skin or blood, which under the right conditions can be coaxed into forming three-dimensional clusters of brain cells. These clusters, a type of organoid, are thought to re-create some aspects of early human brain development, a period that is otherwise difficult to study (SN: 2/20/18). The new results highlight underappreciated differences between these organoids and the human brains they are designed to mimic. “Most of the papers out there are extolling the virtues of these things,” says study coauthor Arnold Kriegstein, a developmental neurobiologist at the University of California, San Francisco. But the new study reveals “significant issues that nobody has addressed yet.” Kriegstein and colleagues compared genetic activity in human cells from brain tissue in early development with human cells grown in an organoid. Cells in the organoids had more active genes involved in stress responses. What’s more, these organoid cells didn’t fit into the neat categories of cells in actual brain tissue. Instead, some of the organoid cells showed features of two distinct categories simultaneously. “They are not normal,” Kriegstein says. © Society for Science & the Public 2000–2019.

Organoids offer clues to how brains are made in humans and chimpanzees

By Laura Sanders Brainlike blobs made from chimpanzee cells mature faster than those grown from human cells. That finding, described October 16 in Nature along with other clues to human brain development, is one of the latest insights from studies of cerebral organoids — three-dimensional clumps of cells that can mimic aspects of early brain growth (SN: 2/20/18). The new study “draws interesting parallels, but also highlights important differences” in the way that the brains of humans and chimpanzees develop, says Paola Arlotta, a neurobiologist at Harvard University who was not involved in the study. While “it’s still early days in the organoid world,” the results represent an important step toward understanding the particulars of the human brain, she says. To make cerebral organoids from chimpanzees, researchers use cells in blood left over from veterinarians’ routine blood draws. In the vials were white blood cells that could be reprogrammed into stem cells, which themselves were then coaxed into blobs of brain cells. “From that, we get something that really looks a lot like the early brain,” says Gray Camp, a stem cell biologist at the Institute of Molecular and Clinical Ophthalmology Basel in Switzerland. There were no obvious differences in appearance between the chimpanzee organoids and the human organoids, Camp says. But a close look at how genes behaved in the two organoids — and how that behavior changed over time — turned up a big difference in pacing. Chimpanzee organoids seemed to grow up faster than their human counterparts. © Society for Science & the Public 2000–2019

Related chapters from BN8e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 26713 - Posted: 10.17.2019

Being Young, Active and Physically Fit May Be Very Good for Your Brain

By Gretchen Reynolds Physically fit young adults have healthier white matter in their brains and better thinking skills than young people who are out of shape, according to a large-scale new study of the links between aerobic fitness and brain health. The findings suggest that even when people are youthful and presumably at the peak of their mental prowess, fitness — or the lack of it — may influence how well their brains and minds work. We already have plenty of tantalizing evidence that aerobic fitness can beneficently shape our brains and cognition. In animal experiments, mice and rats that run on wheels or treadmills produce far more new neurons in their brains than sedentary animals and perform better on tests of rodent intelligence and memory. Similarly, studies involving people show strong relationships between being physically active or fit and having greater brain volume and stronger thinking abilities than people with low fitness or who rarely exercise. But most of these past studies focused on middle-aged or older adults, whose brains often are starting to sputter and contract with age. For them, fitness and exercise are believed to help slow any decline, keeping brain tissue and function relatively youthful. Much less has been known about whether fitness likewise might be related to the structure and function of healthy, younger people’s brains. So, for the new study, which was published last month in Scientific Reports, scientists at the University of Münster in Germany decided to look inside the skulls of a large group of young adults. They began by turning to a hefty trove of data gathered as part of the Human Connectome Project, an international collaborative effort that aims to help map much of the human brain and tease out how it works. © 2019 The New York Times Company

Related chapters from BN8e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 5: The Sensorimotor System
Link ID: 26662 - Posted: 10.02.2019

Vaginal birth and Caesarean: Differences in babies' bacteria

By James Gallagher Health and science correspondent, BBC News Babies born by Caesarean section have dramatically different gut bacteria to those born vaginally, according to the largest study in the field. The UK scientists say these early encounters with microbes may act as a "thermostat" for the immune system. And they may help explain why Caesarean babies are more likely to have some health problems later in life. The researchers stress women should not swab babies with their vaginal fluids - known as "vaginal seeding". How important are gut bacteria? Our bodies are not entirely human - instead we are an ecosystem with around half our body's cells made up of microbes such as bacteria, viruses and fungi. Most of them live in our gut and are collectively known as our microbiome. The microbiome is linked to diseases including allergy, obesity, inflammatory bowel disease, Parkinson's, whether cancer drugs work and even depression and autism. This study - by Wellcome Sanger Institute, UCL, and the University of Birmingham - assessed how the microbiome forms when we leave our mother's sterile womb and enter a world full of bugs. Regular samples were taken from the nappies of nearly 600 babies for the first month of life, and some provided faecal samples for up to a year. © 2019 BBC

Related chapters from BN8e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 26637 - Posted: 09.23.2019

Air pollution particles found on foetal side of placentas

Damian Carrington Environment editor Air pollution particles have been found on the foetal side of placentas, indicating that unborn babies are directly exposed to the black carbon produced by motor traffic and fuel burning. The research is the first study to show the placental barrier can be penetrated by particles breathed in by the mother. It found thousands of the tiny particles per cubic millimetre of tissue in every placenta analysed. The link between exposure to dirty air and increased miscarriages, premature births and low birth weights is well established. The research suggests the particles themselves may be the cause, not solely the inflammatory response the pollution produces in mothers. Damage to foetuses has lifelong consequences and Prof Tim Nawrot at Hasselt University in Belgium, who led the study, said: “This is the most vulnerable period of life. All the organ systems are in development. For the protection of future generations, we have to reduce exposure.” He said governments had the responsibility of cutting air pollution but that people should avoid busy roads when possible. A comprehensive global review concluded that air pollution may be damaging every organ and virtually every cell in the human body. Nanoparticles have also been found to cross the blood-brain barrier and billions have been found in the hearts of young city dwellers. While air pollution is reducing in some nations, the evidence of harm caused by even low levels is rapidly increasing and 90% of the world’s population live in places where air pollution is above World Health Organization (WHO) guidelines. © 2019 Guardian News & Media Limited

Infographic: The Genetics of Fragile X Syndrome

Randi Hagerman Fragile X syndrome is caused by an expansion of CGG nucleotide repeats in the FMR1 gene at the end of the long arms of the X chromosome. To identify the mutation, researchers culture cells in media deficient in folic acid, which causes the ends of the X chromosome to appear as though they are about to break off. Before molecular testing, this was the only way to see the mutation. The FMR1 gene encodes the fragile X mental retardation protein (FMRP), which regulates gene expression and protein translation in the brain. FMRP is important for maintaining synaptic plasticity and the ability to make new neurons. Levels of FMRP associated with disease severity in patients with FXS. © 1986–2019 The Scientist

Culture helps shape when babies learn to walk

Culture helps shape when babies learn to walk By Sujata Gupta For generations, farther back than anyone can remember, the women in Rano Dodojonova’s family have placed their babies in “gahvoras,” cradles that are part diaper, part restraining device. Dodojonova, a research assistant who lives in Tajikistan, was cradled for the first two or three years of her life. She cradled her three children in the same way. Ubiquitous throughout Central Asia, the wooden gahvora is often a gift for newlyweds. The mother positions her baby on his back with his bottom firmly over a hole. Underneath is a bucket to capture whatever comes out. She then binds the baby with several long swaths of fabric so that only the baby’s head can move. Next, she connects a funnel, specially designed for either boys or girls, to send urine out to that same bucket under the cradle. Finally, she drapes heavy fabric over the handle atop the gahvora to protect the child from bright light and insects. Babies stay in that womblike apparatus for hours on end, with use decreasing as the child ages. When babies fuss, mothers often shush them by vigorously rocking the cradle back and forth or leaning over the side to breastfeed. Besides keeping babies dry and warm, gahvoras provide a sense of safety, Dodojonova says. “It is very nice for children because they are bound and cannot move.” Eventually, they are running and jumping like children everywhere. To the uninitiated, this child-rearing approach may sound odd, or even shocking. Yet cultures should be viewed within their own context, says psychologist Catherine Tamis-LeMonda of New York University. “We engage in practices that fit our needs, our own everyday lives.” © Society for Science & the Public 2000–2019.

Recent Trials for Fragile X Syndrome Offer Hope

Randi Hagerman When I visited Ricaurte, Colombia, in 2016, I was surrounded by men with long faces and prominent ears. As we spoke, they would ask repetitive questions while mumbling and failing to maintain eye contact, and when they shook my hand, they turned their body away from me. They were interested in me but were too shy to interact. This type of anxiety-related approach-withdrawal behavior is typical of those with fragile X syndrome (FXS), a well-characterized genetic disease that is the most common inherited form of intellectual disability and the most common single-gene cause of autism. Even many of the Ricaurte women, who usually have at least one good copy of the X chromosome, showed similar social deficits. I had never seen so many individuals with FXS all together. I thought to myself: This is ground zero for FXS. Likely because the founding families of this small village had one or more carriers of the causative mutation, Ricaurte has the highest known prevalence of FXS in the world. Last year, our team published the results of genetic testing of almost all of the inhabitants in this village. We found that nearly 5 percent of male and more than 3 percent of female inhabitants of Ricaurte have FXS,1 compared to around 0.02 percent of people living in the US and in Europe. In Ricaurte, the residents are supportive of these individuals, who work in the community and are well accepted. Their behavior does not seem unusual to those living in the village. Relatives who have moved away from Ricaurte and then subsequently have had a child with FXS will move back to this town for the acceptance and support they find there. This pattern further enhances the genetic cluster of FXS-causing mutations in this area. © 1986–2019 The Scientist.

Related chapters from BN8e: Chapter 1: Biological Psychology: Scope and Outlook
Related chapters from MM:Chapter 1: An Introduction to Brain and Behavior
Link ID: 26582 - Posted: 09.06.2019

First hint that body’s ‘biological age’ can be reversed

Alison Abbott A small clinical study in California has suggested for the first time that it might be possible to reverse the body’s epigenetic clock, which measures a person’s biological age. For one year, nine healthy volunteers took a cocktail of three common drugs — growth hormone and two diabetes medications — and on average shed 2.5 years of their biological ages, measured by analysing marks on a person’s genomes. The participants’ immune systems also showed signs of rejuvenation. The results were a surprise even to the trial organizers — but researchers caution that the findings are preliminary because the trial was small and did not include a control arm. “I’d expected to see slowing down of the clock, but not a reversal,” says geneticist Steve Horvath at the University of California, Los Angeles, who conducted the epigenetic analysis. “That felt kind of futuristic.” The findings were published on 5 September in Aging Cell. “It may be that there is an effect,” says cell biologist Wolfgang Wagner at the University of Aachen in Germany. “But the results are not rock solid because the study is very small and not well controlled.” Marks of life The epigenetic clock relies on the body’s epigenome, which comprises chemical modifications, such as methyl groups, that tag DNA. The pattern of these tags changes during the course of life, and tracks a person’s biological age, which can lag behind or exceed chronological age. © 2019 Springer Nature Publishing AG

Organoids Are Not Brains. How Are They Making Brain Waves?

By Carl Zimmer SAN DIEGO — Two hundred and fifty miles over Alysson Muotri’s head, a thousand tiny spheres of brain cells were sailing through space. The clusters, called brain organoids, had been grown a few weeks earlier in the biologist’s lab here at the University of California, San Diego. He and his colleagues altered human skin cells into stem cells, then coaxed them to develop as brain cells do in an embryo. The organoids grew into balls about the size of a pinhead, each containing hundreds of thousands of cells in a variety of types, each type producing the same chemicals and electrical signals as those cells do in our own brains. In July, NASA packed the organoids aboard a rocket and sent them to the International Space Station to see how they develop in zero gravity. Now the organoids were stowed inside a metal box, fed by bags of nutritious broth. “I think they are replicating like crazy at this stage, and so we’re going to have bigger organoids,” Dr. Muotri said in a recent interview in his office overlooking the Pacific. What, exactly, are they growing into? That’s a question that has scientists and philosophers alike scratching their heads. On Thursday, Dr. Muotri and his colleagues reported that they have recorded simple brain waves in these organoids. In mature human brains, such waves are produced by widespread networks of neurons firing in synchrony. Particular wave patterns are linked to particular forms of brain activity, like retrieving memories and dreaming. As the organoids mature, the researchers also found, the waves change in ways that resemble the changes in the developing brains of premature babies. “It’s pretty amazing,” said Giorgia Quadrato, a neurobiologist at the University of Southern California who was not involved in the new study. “No one really knew if that was possible.” © 2019 The New York Times Company

Clumps of cells in the lab spontaneously formed brain waves

By Laura Sanders It’s baby’s first brain wave, sort of. As lentil-sized clusters of nerve cells grow in a lab dish, they begin to fire off rhythmic electrical signals. These oscillations share some features with those found in the brains of developing human babies, researchers report October 3 in Cell Stem Cell. Three-dimensional spheres of human brain cells, called cerebral organoids, are extremely simplistic models of the human brain. Still, these easy-to-obtain organoids may offer a better way to study how a brain is made, and how that process can go wrong (SN: 2/20/18). “The field is white-hot,” with fast progress in both making and understanding brain organoids, says John Huguenard, a neuroscientist at Stanford University not involved in the study. Finding this sort of coordinated electrical activity in organoids’ nerve cells, or neurons, is a first, he says. “The neurons are growing up and becoming mature enough where they can not only start to behave like neurons and fire individually, but now they can be coordinated.” For the study, researchers coaxed stem cells into forming some of the neurons that make up the outer layer of the brain. These cortical organoids grew in lab dishes that held arrays of electrodes printed along the bottom, allowing the scientists to monitor electrical activity as the organoids developed. © Society for Science & the Public 2000–2019

Babies born after opioid exposure deserve legal recognition, lawyers argue

By Lenny Bernstein With a nationwide prescription opioid lawsuit scheduled for trial in two months, attorneys for newborns suffering from exposure to opioids in the womb have made a last-ditch plea for special legal treatment for the infants and their guardians. Attorneys representing a group that may number more than 250,000 children have spent much of the past two years seeking a separate trial against drug companies but have been rebuffed twice by the judge who oversees the sprawling legal case. The children are still included in that lawsuit, along with about 2,000 other plaintiffs, against some two dozen defendants from the pharmaceutical industry. The children’s lawyers also have complained that attorneys for cities and counties spearheading the lawsuit have refused to let them take part in settlement negotiations that are occurring as the trial date approaches. The attorneys, from 20 firms that represent children across the country, insist that a settlement or verdict must yield billions of dollars specifically earmarked for years-long monitoring of the physical and mental health of children born with “neonatal abstinence syndrome.” That is the formal name for the cluster of difficult symptoms endured by babies who undergo withdrawal from opioids in the days after birth. Without that guarantee, the attorneys contend, cities and towns are likely to spend any money they receive from drug companies on more pressing and popular needs, as some states did with windfalls from the $206 billion settlement with tobacco companies two decades ago. “Our goal is to make sure that we do not have a tobacco-style settlement, where all of the money goes to the governmental entities, and there’s not a significant trust set aside to help these children,” said Stuart Smith, one of the lawyers representing the families. © 1996-2019 The Washington Post

Drinking fluoridated water during pregnancy may lower IQ in sons, controversial study says

By Michael Price First piloted as an experiment to reduce dental cavities in Grand Rapids, Michigan, in 1945, fluoridated drinking water has since been hailed by the U.S. Centers for Disease Control and Prevention in Atlanta as “one of public health’s greatest success stories.” Today, about two-thirds of people in the United States receive fluoridated tap water, as do many people in Australia, Brazil, Canada, New Zealand, Spain, and the United Kingdom. Now, a controversial new study links fluoridation to lower IQ in young children, especially boys whose mothers drank fluoridated water while pregnant. Longtime fluoridation critics are lauding the study, but other researchers say it suffers from numerous flaws that undercut its credibility. Either way, “It’s a potential bombshell,” says Philippe Grandjean, an environmental health researcher at Harvard University who wasn’t involved in the work. Fluoride is well-known for protecting teeth against cavities by strengthening tooth enamel. It’s found naturally in low concentrations in both freshwater and seawater, as well as in plant material, especially tea leaves. Throughout the 1940s and ’50s, public health researchers and government officials in cities around the world experimentally added fluoride to public drinking water; they found it reduced the prevalence of cavities by about 60%. Today, fluoridated water flows through the taps of about 5% of the world’s population, including 66% of Americans and 38% of Canadians. Yet skepticism has dogged the practice for as long as it has existed. Some have blamed fluoridated water for a wide range of illnesses including cancer, but most criticism has been dismissed as pseudoscience. Over the years, though, a small number of scientists have published meta-analyses casting doubt on the efficacy of water fluoridation in preventing cavities. More recently, scientists have published small-scale studies that appear to link prenatal fluoride exposure to lower IQ, although dental research groups were quick to challenge them. © 2019 American Association for the Advancement of Science.

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: 26516 - Posted: 08.19.2019

Heel Prick, 1957

Ashley Yeager Drops of blood, filter paper, bacteria, a bacterial inhibitor, and a baking dish—that’s all it took for microbiologist Robert Guthrie to develop a basic test for phenylketonuria, a genetic metabolic disease that, if left untreated in infants, soon leads to neurological dysfunction and intellectual disability. The test would lay the foundation for screening newborns for diseases. In 1957, Guthrie met Robert Warner, a specialist who diagnosed individuals with mental disabilities. Warner told Guthrie about phenylketonuria (PKU), now known to affect roughly 1 in 10,000 children. The disease makes it impossible to break down the amino acid phenylalanine, so that it builds up to toxic levels in the body and disrupts neuronal communication. Once a child was diagnosed, a strict low-phenylalanine diet could prevent further damage, but Warner had no easy way to measure phenylalanine levels in his PKU patients’ blood to monitor the diet’s effects. He asked Guthrie for help. Guthrie reported back to Warner three days later with a solution. Guthrie knew from past work that the bacterial inhibitor β-2-thienylalanine blocked Bacillus subtilis from flourishing by substituting for phenylalanine in growing peptide chains, resulting in inactive proteins. He also knew that adding phenylalanine to the cell cultures restored normal protein function and spurred the bacterium’s growth. So his solution was simple: prick the skin, collect a few drops of blood on filter paper, and place the filter paper in a baking pan covered in β-2-thienylalanine. Add Bacillus subtilis to the filter paper and heat the pan overnight. If the bacterium grows exponentially, the level of phenylalanine is high. The assay worked well, so Guthrie used it as a model to develop tests for other metabolic diseases. © 1986–2019 The Scientist

The 'brutal reality' for alcohol-damaged children

A mother has laid bare the "brutal reality" of bringing up her adoptive son after he was left damaged by exposure to alcohol in the womb. Judith Knox says her 12-year-old son has a range of behavioural problems as a result of Foetal Alcohol Spectrum Disorder (FASD). It is estimated that as many as 172,000 people could be affected by the disorder in Scotland. But Ms Knox said it took six years for her son to be properly diagnosed. FASD is an umbrella term that describes the adverse physical and emotional conditions that affect people whose mother drank during pregnancy. A new support service for parents and carers, called FASD Hub Scotland, has now been launched. Ms Knox, who does not want to name her son or identify him through recent pictures, said the service was long overdue. She told BBC Scotland: "This has put a lot of strain on the family. "Your parenting is always being scrutinised and he just wants 100% of your attention, 100% of the time." The 51-year-old and her ex-husband adopted their son at the age of seven months and he quickly began to exhibit a raft of worrying behaviour. This included biting his fingers until they bled in a bid to stave off sleep, picking plaster from the walls to eat and ignoring the range of toys his family had bought him. Her son was eventually diagnosed with FASD at the age of six, after doctors initially wrongly thought he had Attention Deficit Hyperactivity Disorder. But his behaviour continued to push his family to their limits.

Children’s brains reorganize after epilepsy surgery to retain visual perception

Children can keep full visual perception — the ability to process and understand visual information — after brain surgery for severe epilepsy, according to a study funded by the National Eye Institute (NEI), part of the National Institutes of Health. While brain surgery can halt seizures, it carries significant risks, including an impairment in visual perception. However, a new report by Carnegie Mellon University, Pittsburgh, researchers from a study of children who had undergone epilepsy surgery suggests that the lasting effects on visual perception can be minimal, even among children who lost tissue in the brain’s visual centers. Normal visual function requires not just information sent from the eye (sight), but also processing in the brain that allows us to understand and act on that information (perception). Signals from the eye are first processed in the early visual cortex, a region at the back of the brain that is necessary for sight. They then travel through other parts of the cerebral cortex, enabling recognition of patterns, faces, objects, scenes, and written words. In adults, even if their sight is still present, injury or removal of even a small area of the brain’s vision processing centers can lead to dramatic, permanent loss of perception, making them unable to recognize faces, locations, or to read, for example. But in children, who are still developing, this part of the brain appears able to rewire itself, a process known as plasticity. “Although there are studies of the memory and language function of children who have parts of the brain removed surgically for the treatment of epilepsy, there have been rather few studies that examine the impact of the surgery on the visual system of the brain and the resulting perceptual behavior,” said Marlene Behrmann, Ph.D., senior author of the study. “We aimed to close this gap.”

Related chapters from BN8e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 7: Vision: From Eye to Brain
Link ID: 26303 - Posted: 06.05.2019

A cognitive neuroscientist warns that the U.S. justice system harms teen brains

Laura Sanders A teenager’s brain does not magically mature into its reasoned, adult form the night before his or her 18th birthday. Instead, aspects of brain development stretch into a person’s 20s — a protracted fine-tuning with serious implications for young people caught in the U.S. justice system, argues cognitive neuroscientist B.J. Casey of Yale University. In the May 22 Neuron, Casey describes the heartbreaking case of Kalief Browder, sent at age 16 to Rikers Island correctional facility in New York City after being accused of stealing a backpack. Unable to come up with the $3,000 bail, Browder spent three years in the violent jail before his case was ultimately dropped. About two-thirds of his time in custody was spent in solitary confinement — “a terrible place for a child to have to grow up,” Casey says. Two years after his 2013 release, Browder died from suicide. Casey uses the case to highlight how the criminal justice system — and the accompanying violence, stress and isolation (SN: 12/8/18, p. 11) that come with being incarcerated — can interfere with brain development in adolescents and children. Other recent stories of immigrant children being separated from their families and held in detention centers have raised similar concerns (SN Online: 6/20/18). Studies with lab animals and brain imaging experiments in people show that chronic stress and other assaults “impact the very brain circuitry that is changing so radically during adolescence,” Casey says. An abundance of science says that “the way we’re treating our young people is not the way to a healthy development.” |© Society for Science & the Public 2000 - 2019

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Links for Keyword: Development of the Brain