Chapter 7. Life-Span Development of the Brain and Behavior

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By BILL PENNINGTON BOSTON — The drumbeat of alarming stories linking concussions among football players and other athletes to brain disease has led to a new and mushrooming American phenomenon: the specialized youth sports concussion clinic, which one day may be as common as a mall at the edge of town. In the last three years, dozens of youth concussion clinics have opened in nearly 35 states — outpatient centers often connected to large hospitals that are now filled with young athletes complaining of headaches, amnesia, dizziness or problems concentrating. The proliferation of clinics, however, comes at a time when there is still no agreed-upon, established formula for treating the injuries. “It is inexact, a science in its infancy,” said Dr. Michael O’Brien of the sports concussion clinic at Boston Children’s Hospital. “We know much more than we once did, but there are lots of layers we still need to figure out.” Deep concern among parents about the effects of concussions is colliding with the imprecise understanding of the injury. To families whose anxiety has been stoked by reports of former N.F.L. players with degenerative brain disease, the new facilities are seen as the most expert care available. That has parents parading to the clinic waiting rooms. The trend is playing out vividly in Boston, where the phone hardly stops ringing at the youth sports concussion clinic at Massachusetts General Hospital. “Parents call saying, ‘I saw a scary report about concussions on Oprah or on the ‘Doctors’ show or Katie Couric’s show,’ ” Dr. Barbara Semakula said, describing a typical day at the clinic. “Their child just hurt his head, and they’ve already leapt to the worst possible scenarios. It’s a little bit of a frenzy out there.” © 2013 The New York Times Company

Keyword: Brain Injury/Concussion; Aggression
Link ID: 18121 - Posted: 05.06.2013

By John Horgan What is mental illness? Schizophrenia? Autism? Bipolar disorder? Depression? Since the 1950s, the profession of psychiatry has attempted to provide definitive answers to these questions in the Diagnostic and Statistical Manual of Mental Disorders. Often called The Bible of psychiatry, the DSM serves as the ultimate authority for diagnosis, treatment and insurance coverage of mental illness. Now, in a move sure to rock psychiatry, psychology and other fields that address mental illness, the director of the National Institutes of Mental Health has announced that the federal agency–which provides grants for research on mental illness–will be “re-orienting its research away from DSM categories.” Thomas Insel’s statement comes just weeks before the scheduled publication of the DSM-V, the fifth edition of the Diagnostic and Statistical Manual. Insel writes: “While DSM has been described as a ‘Bible’ for the field, it is, at best, a dictionary, creating a set of labels and defining each. The strength of each of the editions of DSM has been ‘reliability’–each edition has ensured that clinicians use the same terms in the same ways. The weakness is its lack of validity. Unlike our definitions of ischemic heart disease, lymphoma, or AIDS, the DSM diagnoses are based on a consensus about clusters of clinical symptoms, not any objective laboratory measure. In the rest of medicine, this would be equivalent to creating diagnostic systems based on the nature of chest pain or the quality of fever. Indeed, symptom-based diagnosis, once common in other areas of medicine, has been largely replaced in the past half century as we have understood that symptoms alone rarely indicate the best choice of treatment. Patients with mental disorders deserve better.” © 2013 Scientific American

Keyword: Schizophrenia; Aggression
Link ID: 18120 - Posted: 05.06.2013

Alla Katsnelson People who use a ‘brain-workout’ program for just 10 hours have a mental edge over their peers even a year later, researchers report today in PLoS ONE1. The search for a regimen of mental callisthenics to stave off age-related cognitive decline is a booming area of research — and a multimillion-dollar business. But critics argue that even though such computer programs can improve performance on specific mental tasks, there is scant proof that they have broader cognitive benefits. For the study, adults aged 50 and older played a computer game designed to boost the speed at which players process visual stimuli. Processing speed is thought to be “the first domino that falls in cognitive decline”, says Fredric Wolinsky, a public-health researcher at the University of Iowa in Iowa City, who led the research. The game was developed by academic researchers but is now sold under the name Double Decision by Posit Science, based in San Francisco, California. (Posit did not fund the study.) Players are timed on how fast they click on an image in the centre of the screen and on others that appear around the periphery. The program ratchets up the difficulty as a player’s performance improves. Participants played the training game for 10 hours on site, some with an extra 4-hour ‘booster’ session later, or for 10 hours at home. A control group worked on computerized crossword puzzles for 10 hours on site. Researchers measured the mental agility of all 621 subjects before the brain training began, and again one year later, using eight well-established tests of cognitive performance. © 2013 Nature Publishing Group

Keyword: Learning & Memory; Aggression
Link ID: 18109 - Posted: 05.02.2013

Chris Palmer NF-kB activation in neurons in the hypothalamus increases with age (left column), while the total number of neurons (middle column) and the total number of all cell types in the hypothalamus (right column) is maintained at a relatively steady rate across age groups. The area of the brain that controls growth, reproduction and metabolism also kick-starts ageing, according to a study published today in Nature1. The finding could lead to new treatments for age-related illnesses, helping people to live longer. Dongsheng Cai, a physiologist at Albert Einstein College of Medicine in New York, and his colleagues tracked the activity of NF-κB — a molecule that controls DNA transcription and is involved in inflammation and the body's response to stress — in the brains of mice. They found that the molecule becomes more active in the brain area called the hypothalamus as a mouse grows older. Further tests suggested that NF-κB activity helps to determine when mice display signs of ageing. Animals lived longer than normal when they were injected with a substance that inhibited the activity of NF-κB in immune cells called microglia in the hypothalamus. Mice that received a substance to stimulate the activity of NF-κB died earlier. “We have provided scientific evidence for the concept that systemic ageing is influenced by a particular tissue in the body,” says Cai. Health and well-being © 2013 Nature Publishing Group

Keyword: Development of the Brain; Aggression
Link ID: 18108 - Posted: 05.02.2013

By NICHOLAS BAKALAR A large new study confirms that sticking to the Mediterranean diet — fish, poultry, vegetables and fruit, with minimal dairy foods and meat — may be good for the brain. Researchers prospectively followed 17,478 mentally healthy men and women 45 and older, gathering data on diet from food questionnaires, and testing mental function with a well-validated six-item screening tool. They ranked their adherence to the Mediterranean diet on a 10-point scale, dividing the group into low adherence and high adherence. The study was published April 30 in the journal Neurology. During a four-year follow-up, 1,248 people became cognitively impaired. But those with high adherence to the diet were 19 percent less likely to be among them. This association persisted even after controlling for almost two dozen demographic, environmental and vascular risk factors, and held true for both African-Americans and whites. The study included 2,913 people with Type 2 diabetes, but for them adherence to the diet had no effect on the likelihood of becoming impaired. The lead author, Dr. Georgios Tsivgoulis, an assistant professor of neurology at the University of Athens, said that this is the largest study of its kind. The Mediterranean diet, he added, “has many benefits — cardiovascular, cancer risk, anti-inflammatory, central nervous system. We’re on the tip of the iceberg, and trying to understand what is below.” Copyright 2013 The New York Times Company

Keyword: Obesity; Aggression
Link ID: 18100 - Posted: 05.01.2013

By Russell Foster "Making teens start school in the morning is ‘cruel,’ brain doctor claims." So declared a British newspaper headline in 2007 after a talk I gave at an academic conference. One disbelieving reader responded: "This man sounds brain-dead." That was a typical reaction to work I was reporting at the time on teenage sleep patterns and their effect on performance at school. Six years on, there is growing acceptance that the structure of the academic day needs to take account of adolescent sleep patterns. The latest school to adopt a later start time is the UCL Academy in London; others are considering following suit. So what are the facts about teenage slumber, and how should society adjust to these needs? The biology of human sleep timing, like that of other mammals, changes as we age. This has been shown in many studies. As puberty begins, bedtimes and waking times get later. This trend continues until 19.5 years in women and 21 in men. Then it reverses. At 55 we wake at about the time we woke prior to puberty. On average this is two hours earlier than adolescents. This means that for a teenager, a 7 a.m. alarm call is the equivalent of a 5 a.m. start for people in their 50s. Precisely why this is so is unclear, but the shifts correlate with hormonal changes at puberty and the decline in those hormones as we age. However, biology is only part of the problem. Additional factors include a more relaxed attitude to bedtimes by parents, a general disregard for the importance of sleep, and access to TVs, DVDs, PCs, gaming devices, cellphones, and so on, all of which promote alertness and eat into time available for sleep. © 2013 The Slate Group, LLC.

Keyword: Sleep; Aggression
Link ID: 18084 - Posted: 04.27.2013

by Emily Underwood In the cartoon series named after them, Pinky and the Brain, two laboratory mice genetically enhanced to increase their intelligence plot to take over the world—and fail each time. Perhaps their creators hadn't tweaked the correct gene. Researchers have now found a genetic mutation that causes mammalian neural tissue to expand and fold. The discovery may help explain why humans evolved more elaborate brains than mice, and it could suggest ways to treat disorders such as autism and epilepsy that arise from abnormal neural development. In mice and humans alike, the cerebral cortex—the outermost layer of brain tissue associated with high-level functions such as memory and decision-making—starts out as a spherical sheet of tissue made up of only neural stem cells. As these stem cells divide, the cortex increases its surface area, expanding like an inflating balloon, says neuroscientist Victor Borrell of the Institute of Neurosciences of Alicante in Spain. Unlike the small, smooth mouse brain, however, the uppermost layers of tissue in the human brain cram millions of neurons into specialized folds and furrows responsible for complex tasks such as language and thought. Because the human cerebral cortex is generally considered "special," some scientists have hypothesized that the genes that govern its development of cortical folds and furrows are also unique to humans, Borrell says. In studies of neural development in mice, Stahl found that TRNP1 produces a protein that determines whether neural stem cells self-replicate, leading to a balloonlike expansion of cortical surface area, or whether they differentiate into a plethora of intermediate stem cell types and neurons, thickening the cortex and forming more complex brain structures. Based on that discovery, the team hypothesized that varying levels of the gene's expression in mice and humans might account for the varying levels of cortical thickness and different shapes between the two species. © 2010 American Association for the Advancement of Science

Keyword: Development of the Brain; Aggression
Link ID: 18082 - Posted: 04.27.2013

by Dr. Claire McCarthy April is Autism Awareness Month--and if there's anything that we need when it comes to autism, it's awareness. We need people to be aware of this condition that affects a staggering 1 in 50 children, so that we can understand what causes it, and find ways to prevent it. And we need people to be aware of the signs of autism--because getting help early can make a real difference. Many children aren't diagnosed with autism until they get to preschool, or sometimes even later--and that means important time is lost. The signs of autism can be present in toddlers--and when we find it then, we can get help to those children and their families right away. The trick is in asking the right questions--and acting on the answers. In the practice where I work, as in many other practices, we ask parents to fill out questionnaires about the behavior and development of their children. At the 18 month and 24 month visits, we ask parents to fill out one called the MCHAT (Modified Checklist for Autism in Toddlers)--that's the tool we've chosen to help us look for autism. It's a list of questions that parents answer yes or no to, questions about how their child acts, plays and interacts with other people. While all the questions on the MCHAT are important, there are six that are most important: Does your child take an interest in other children? Does your child ever use his finger to point at or ask for something? Does your child ever bring objects over to you to show you something? Does your child imitate you? Does your child respond to his name when you call? If you point at a toy across the room, does your child look at it? © 2013 NY Times Co.

Keyword: Autism
Link ID: 18081 - Posted: 04.27.2013

By Karen Rowan and MyHealthNewsDaily Children at an increased risk of autism may have abnormal structures in the placenta that can be detected at birth, a new study finds. The findings suggest behavioral interventions aimed at social and motor skill development in these children could be started right away, the researchers said. Studies have shown that such interventions are more effective in children with autism when they are started earlier. It's much too early to say that an examination of the placenta could be used as a definitive test for autism at birth, said study researcher Dr. Harvey Kliman, director of Reproductive and Placental Research at the Yale University School of Medicine. Autism spectrum disorders are typically diagnosed when children are ages 3 or 4, or even older. However, if these structures were found upon a child's birth and interventions were started, the child might benefit greatly if they did turn out to have autism, while there would be little downside if a child turned out not to have autism -- it's unlikely they would be harmed by the effort, Kliman said. In the study, Kliman and his colleagues collected samples of placenta tissue from 117 children born to families who already had a child with autism, and compared them with placentas from 100 babies born into families in which no older children had autism. The researchers, who didn't know which placentas had come from each group of children, examined samples of the placentas under microscopes. © 2013 Scientific American

Keyword: Autism; Aggression
Link ID: 18080 - Posted: 04.27.2013

By KATIE THOMAS With the diagnosis of autism on the rise and drug companies facing major setbacks in developing successful treatments, the University of California, Los Angeles will lead a $9 million effort financed by the National Institute of Mental Health to find effective drugs, officials said Wednesday. Under a contract with the institute, U.C.L.A. will form a network of researchers at other academic centers that will try to identify promising new and older drug compounds quickly, and conduct early tests to see if they merit additional investment. The program, part of the “Fast Fail” initiative at the institute, aims to determine within weeks whether a drug works, rather than the years it traditionally takes to evaluate a new drug. “The whole idea is just getting much better in these early phases at identifying drugs that are going to be efficacious and safe, and thereby greatly speeding the development of effective new therapies and reducing the overall cost,” said Dr. James McCracken, who is leading the effort at U.C.L.A. as director of the division of child and adolescent psychiatry at the Semel Institute for Neuroscience and Human Behavior. The number of diagnosed cases of autism, Asperger’s syndrome and related disorders in children has been growing in recent years, largely because of increased awareness. A recent report by the Centers for Disease Control and Prevention and the Health Resources and Services Administration concluded that one in 50 children aged 6 to 17 had been found to have autism or a related disorder, a 72 percent increase since 2007. Although more cases are being diagnosed, no drugs are approved to treat the core symptoms of the disorders, which are characterized by delays in developing effective communication and social skills. Other drugs often prescribed to people with the disorders treat difficult behaviors like aggressiveness, hyperactivity and irritability. © 2013 The New York Times Company

Keyword: Autism
Link ID: 18070 - Posted: 04.25.2013

By PAM BELLUCK After most pregnancies, the placenta is thrown out, having done its job of nourishing and supporting the developing baby. But a new study raises the possibility that analyzing the placenta after birth may provide clues to a child’s risk for developing autism. The study, which analyzed placentas from 217 births, found that in families at high genetic risk for having an autistic child, placentas were significantly more likely to have abnormal folds and creases. “It’s quite stark,” said Dr. Cheryl K. Walker, an obstetrician-gynecologist at the Mind Institute at the University of California, Davis, and a co-author of the study, published in the journal Biological Psychiatry. “Placentas from babies at risk for autism, clearly there’s something quite different about them.” Researchers will not know until at least next year how many of the children, who are between 2 and 5, whose placentas were studied will be found to have autism. Experts said, however, that if researchers find that children with autism had more placental folds, called trophoblast inclusions, visible after birth, the condition could become an early indicator or biomarker for babies at high risk for the disorder. “It would be really exciting to have a real biomarker and especially one that you can get at birth,” said Dr. Tara Wenger, a researcher at the Center for Autism Research at Children’s Hospital of Philadelphia, who was not involved in the study. © 2013 The New York Times Company

Keyword: Autism; Aggression
Link ID: 18069 - Posted: 04.25.2013

By KJ DELL'ANTONIA A cautiously worded study based on data collected in Sweden has found that “in utero exposure to both selective serotonin reuptake inhibitors (S.S.R.I.’s) and nonselective monoamine reuptake inhibitors (tricyclic antidepressants) was associated with an increased risk of autism spectrum disorders, particularly without intellectual disability.” The Swedish medical birth register (which contains data on current drug use reported by mothers early in their pregnancies), along with a system of publicly funded screenings for autism spectrum disorders and extensive national and regional registers of various health issues, make a detailed, population-based case-control study possible — one that controls for other variables like family income, parent educational level, maternal and paternal age and even maternal region of birth (all factors the authors note have been previously associated with autism). This is the second study in two years to associate antidepressant use during pregnancy with an increased incidence of autism in exposed children. An earlier, smaller study in California also found a modest increase in risk. The Sweden-based study could not (and did not) exclude the possibility that it was the severe depression, rather than the use of antidepressants, that created the association, but the smaller California study (which considered only S.S.R.I.’s) found “no increase in risk” for mothers with a history of mental health treatment in the absence of prenatal exposure to S.S.R.I.’s. © 2013 The New York Times Company

Keyword: Autism; Aggression
Link ID: 18064 - Posted: 04.23.2013

By GREGORY COWLES When John Elder Robison was teaching his young son, Cubby, the finer points of etiquette almost two decades ago, he noted that in addition to “please” and “thank you,” it’s nice to include a salutation while making a request. “For example,” he said, “if you wanted me to get you milk, you could say: ‘Please, wondrous Dada, may I have some milk?’ ” The salutation never caught with Cubby. But by the last page of Mr. Robison’s engaging new memoir, readers may have no problem hailing the author that way. Part parenting guide, part courtroom drama, part catalog of the travails and surprising joys of life with the high-functioning form of autism called Asperger’s syndrome, this memoir will offer all parents — but particularly fathers — a lot to think about. That its author was almost 40 when he learned he had Asperger’s (a discovery he described in his first memoir, “Look Me in the Eye”), and that he eventually learned his son had the condition as well, make their story more remarkable, but do nothing to diminish its relevance even for readers with no personal experience of autism. Indeed, it can be hard to pinpoint what in the Robisons’ relationship is shaped by Asperger’s and what stems from their own idiosyncratic personalities. Cubby’s name, for instance: Mr. Robison tells us that when his wife (now ex) was pregnant, “I sensed that the best names were not in books at all. For example, if we ended up with a girl, I favored naming her Thugwena, because I knew a girl named Thugwena would be tough and not hassled by bullies.” For boys he liked Thugwald, or else “functional choices” like Kid or Boy. Is this an example of his deadpan humor, in evidence throughout, or is it his Asperger’s blinding him to how others might perceive his actions? Just when you conclude that his tongue is firmly in his cheek, he drops a passing reference to the family cat, Small Animal. © 2013 The New York Times Company

Keyword: Autism
Link ID: 18063 - Posted: 04.23.2013

By Michelle Roberts Health editor, BBC News online Canadian doctors say they have found an inventive way to treat lazy eye - playing the Tetris video game. The McGill University team discovered the popular tile-matching puzzle could train both eyes to work together. In a small study, in Current Biology with 18 adults, it worked better than conventional patching of the good eye to make the weak one work harder. The researchers now want to test if it would be a good way to treat children with the same condition. UK studies are already under way. An estimated one in 50 children has lazy eye, known medically as amblyopia. It happens when the vision in one eye does not develop properly, and is often accompanied by a squint - where the eyes do not look in the same direction. Without treatment it can lead to a permanent loss of vision in the weak eye, which is why doctors try to intervene early. Normally, the treatment is to cover the strong eye with a patch so that the child is forced to use their lazy eye. The child must wear the patch for much of the day over many months, which can be frustrating and unpleasant. BBC © 2013

Keyword: Vision; Aggression
Link ID: 18062 - Posted: 04.23.2013

By ABBY ELLIN Marvin Tolkin was 83 when he decided that the unexamined life wasn’t worth living. Until then, it had never occurred to him that there might be emotional “issues” he wanted to explore with a counselor. “I don’t think I ever needed therapy,” said Mr. Tolkin, a retired manufacturer of women’s undergarments who lives in Manhattan and Hewlett Harbor, N.Y. Though he wasn’t clinically depressed, Mr. Tolkin did suffer from migraines and “struggled through a lot of things in my life” — the demise of a long-term business partnership, the sudden death of his first wife 18 years ago. He worried about his children and grandchildren, and his relationship with his current wife, Carole. “When I hit my 80s I thought, ‘The hell with this.’ I don’t know how long I’m going to live, I want to make it easier,” said Mr. Tolkin, now 86. “Everybody needs help, and everybody makes mistakes. I needed to reach outside my own capabilities.” So Mr. Tolkin began seeing Dr. Robert C. Abrams, a professor of clinical psychiatry at Weill Cornell Medical College in Manhattan. They meet once a month for 45 minutes, exploring the problems that were weighing on Mr. Tolkin. “Dr. Abrams is giving me a perspective that I didn’t think about,” he said. “It’s been making the transition of living at this age in relation to my family very doable and very livable.” Mr. Tolkin is one of many seniors who are seeking psychological help late in life. Most never set foot near an analyst’s couch in their younger years. But now, as people are living longer, and the stigma of psychological counseling has diminished, they are recognizing that their golden years might be easier if they alleviate the problems they have been carrying around for decades. It also helps that Medicare pays for psychiatric assessments and therapy. Copyright 2013 The New York Times Company

Keyword: Development of the Brain; Aggression
Link ID: 18061 - Posted: 04.23.2013

By Kate Wong Odds are you carry DNA from a Neandertal, Denisovan or some other archaic human. Just a few years ago such a statement would have been virtually unthinkable. For decades evidence from genetics seemed to support the theory that anatomically modern humans arose as a new species in a single locale in Africa and subsequently spread out from there, replacing archaic humans throughout the Old World without mating with them. But in recent years geneticists have determined that, contrary to that conventional view, anatomically modern Homo sapiens did in fact interbreed with archaic humans, and that their DNA persists in people today. In the May issue of Scientific American, Michael Hammer of the University of Arizona in Tucson examines the latest genetic findings and explores the possibility that DNA from these extinct relatives helped H. sapiens become the wildly successful species it is today. As Scientific American’s anthropology editor, I have an enduring interest in the rise of H. sapiens; and as longtime readers of this blog may know, I’m fascinated (you might even say obsessed) with Neandertals. So naturally I’ve been keen to find out how much, if any, Neandertal DNA I have in my own genome. Several consumer genetic testing companies now test for Neandertal genetic markers as part of their broader ancestry analysis, and after 23andMe lowered the price of their kit to $99 in December, I decided to take the plunge. As it happens, National Geographic’s Genographic Project had recently updated their own genetic test to look for Neandertal DNA, and they sent me a kit (retail price: $299) for editorial review, much as publishers do with new books. And so it was on a chilly Saturday in late January that I found myself spitting into a test tube for 23andMe and swabbing my cheek for the Genographic Project. © 2013 Scientific American

Keyword: Evolution; Aggression
Link ID: 18057 - Posted: 04.23.2013

By Emily Chung, CBC News Having a stressed-out mom may give baby squirrels a competitive edge, a new study suggests. Red squirrels who were stressed out during pregnancy had babies that out-competed their peers by growing significantly faster without any extra food, reported the study, published online in Science Express. "What that suggests is that they're first able to predict what sort of environment their offspring will encounter… and they're preparing them for what their offspring are going to face," said Ben Dantzer, lead author of the study he worked on while he was a Ph.D. student at Michigan State University under the supervision of Guelph University biologist Andrew McAdam. Further investigation uncovered a link between faster growth among the baby squirrels and higher levels of stress hormones in their mothers during the pregnancies. That link may explain how environmental conditions cue the animals to respond and adapt. Canadian researchers, including Stan Boutin at the University of Alberta, Murray Humphreys at McGill University in Montreal and McAdam at the University of Guelph, had been studying red squirrels near Kluane Lake, Yukon, for 22 years to find out how they are affected by changes in resources such as food over time. © CBC 2013

Keyword: Stress; Aggression
Link ID: 18049 - Posted: 04.20.2013

by Dennis Normile A human mother rocking a baby in her arms and a cat carrying her kitten by the scruff of its neck have the same physiological effect on both young animals and probably stem from the same maternal instinct to protect their young. That's the conclusion of a new study, which for the first time has compared the physiological impact of maternal carrying behaviors across species. The findings may lead to better parenting techniques for people and possibly to new ways to detect developmental disorders early in life. It's "really fascinating" work, says Oliver Bosch, a neurobiologist at the University of Regensburg in Germany, who was not involved in the research. "No one has looked at [this aspect] of maternal behavior in such detail." Japanese neuroscientist Kumi Kuroda began the study in her own home. She noticed that carrying her newborn baby boy while walking had a rapid calming effect on him. Back in her lab at the RIKEN Brain Science Institute, near Tokyo, she found that picking up mouse pups by the scruff of the neck makes them passive and easy to handle. Kuroda wondered if the same physiological processes were driving both behaviors. She and colleagues recorded pulse rates and observed the crying and squirming behavior of 12 infants, 1 to 6 months old, as each was left alone in a crib, held by its mother sitting in a chair, and carried as the mother walked around. In various durations and combinations of the three conditions, they found that the carried babies cried and squirmed the least and had the lowest pulse rates. Those left in the crib were the fussiest; holding the baby while sitting produced in-between results. What was particularly surprising, Kuroda says, was that when a mother started walking, the infant's pulse dropped, and the crying and squirming stopped within 2 to 3 seconds, not over several minutes. © 2010 American Association for the Advancement of Science.

Keyword: Development of the Brain; Aggression
Link ID: 18048 - Posted: 04.20.2013

by Douglas Heaven A glimpse of consciousness emerging in the brains of babies has been recorded for the first time. Insights gleaned from the work may aid the monitoring of babies under anaesthesia, and give a better understanding of awareness in people in vegetative states – and possibly even in animals. The human brain develops dramatically in a baby's first year, transforming the baby from being unaware to being fully engaged with its surroundings. To capture this change, Sid Kouider at the Ecole Normale Supérieure in Paris, France, and colleagues used electroencephalography (EEG) to record electrical activity in the brains of 80 infants while they were briefly shown pictures of faces. In adults, awareness of a stimulus is known to be linked to a two-stage pattern of brain activity. Immediately after a visual stimulus is presented, areas of the visual cortex fire. About 300 milliseconds later other areas light up, including the prefrontal cortex, which deals with higher-level cognition. Conscious awareness kicks in only after the second stage of neural activity reaches a specific threshold. "It's an all-or-nothing response," says Kouider. Adults can verbally describe being aware of a stimulus, but a baby is a closed book. "We have learned a lot about consciousness in people who can talk about it, but very little in those who cannot," says Tristan Bekinschtein at the University of Cambridge, who was not involved in the work. © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Aggression
Link ID: 18047 - Posted: 04.20.2013

by Simon Makin The first drug specifically designed to improve cognitive impairment in Down's syndrome is being tested in humans. David Nutt, former drug policy adviser to the UK government, told delegates at the Festival of Neuroscience in London yesterday that he is collaborating with pharmaceutical company Roche in trials of a substance it developed, called RG1662. RG1662 reverses the effects of a chemical messenger in the brain called GABA – a neurotransmitter that inhibits brain activity. The drug acts on a specific type of brain receptor found mostly in the hippocampus, a part of the brain involved in memory. It is thought that it will reduce excessive inhibition in the hippocampus, thought to underlie memory and learning problems commonly seen in people with Down's. The study is currently assessing safety and tolerability of the drug in 33 adults with Down's, but researchers will also measure motor skills, reaction time and memory, and compare the results with those of people taking a placebo. The aim is to find appropriate doses to use in a full clinical trial, which Nutt says should happen this year. Roche said in a statement that RG1662 may help people with Down's as it has "a unique pharmacology that enables the targeting of GABA over-activity mainly in brain systems important for cognition, learning and memory". © Copyright Reed Business Information Ltd

Keyword: Learning & Memory
Link ID: 18026 - Posted: 04.13.2013