Chapter 13. Memory, Learning, and Development
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By Maggie Fox Another study aimed at soothing the fears of some parents shows that vaccines don't cause autism. This one takes a special look at children with older siblings diagnosed with autism, who do themselves have a higher risk of an autism spectrum disorder. But even these high-risk kids aren't more likely to develop autism if they're vaccinated, according to the report in the Journal of the American Medical Association. "We found that there was no harmful association between receipt of the MMR (measles, mumps and rubella) vaccine and development of autism spectrum disorder," said Dr. Anjali Jain of The Lewin Group, a health consulting group in Falls Church, Virginia, who led the study. Kids who had older brothers or sisters with autism were less likely to be vaccinated on time themselves, probably because their parents had vaccine worries. But those who were vaccinated were no more likely than the unvaccinated children to develop autism, Jain's team found. Autism is very common. The Centers for Disease Control and Prevention says one in 68 U.S. kids has an autism spectrum disorder. Numbers have been growing but CDC says much of this almost certainly reflects more awareness and diagnosis of kids who would have been missed in years past.
Link ID: 20829 - Posted: 04.22.2015
The brains of babies “light up” in a similar way to adults when exposed to the same painful stimulus, suggesting they feel pain much like adults do, researchers said on Tuesday. In the first of its kind study using magnetic resonance imaging (MRI), scientists from Britain’s Oxford University found that 18 of the 20 brain regions active in adults experiencing pain were also active in babies. Brain scans of the sleeping infants while they were subjected to mild pokes on the bottom of their feet with a special rod – creating a sensation “like being poked with a pencil” – also showed their brains had the same response to a slighter “poke” as adults did to a stimulus four times as strong, suggesting babies have a much lower pain threshold. “Obviously babies can’t tell us about their experience of pain and it is difficult to infer pain from visual observations,” said Rebeccah Slater, a doctor at Oxford’s paediatrics department who led the study. “In fact some people have argued that babies’ brains are not developed enough for them to really feel pain ... [yet] our study provides the first really strong evidence this is not the case.” Even as recently as the 1980s it was common practice for babies undergoing surgery to be given neuromuscular blocks but no pain relief medication. Last year, a review of neonatal pain management in intensive care found that although these babies experience an average of 11 painful procedures per day, 60% do not receive any kind of pain medication. © 2015 Guardian News and Media Limited
By Alix Spiegel In 1979, when Jim Stigler was still a graduate student at the University of Michigan, he went to Japan to research teaching methods and found himself sitting in the back row of a crowded fourth-grade math class. “The teacher was trying to teach the class how to draw three-dimensional cubes on paper,” Stigler explains, “and one kid was just totally having trouble with it. His cube looked all cockeyed, so the teacher said to him, ‘Why don’t you go put yours on the board?’ So right there I thought, ‘That’s interesting! He took the one who can’t do it and told him to go and put it on the board.’ ” Stigler knew that in American classrooms, it was usually the best kid in the class who was invited to the board. And so he watched with interest as the Japanese student dutifully came to the board and started drawing, but still couldn’t complete the cube. Every few minutes, the teacher would ask the rest of the class whether the kid had gotten it right, and the class would look up from their work, and shake their heads no. And as the period progressed, Stigler noticed that he — Stigler — was getting more and more anxious. In Japanese classrooms, teachers consciously design tasks that are slightly beyond the capabilities of the students they teach, so the students can actually experience struggling with something just outside their reach. “I realized that I was sitting there starting to perspire,” he says, “because I was really empathizing with this kid. I thought, ‘This kid is going to break into tears!’ ” © 2015 KQED Inc.
Keyword: Learning & Memory
Link ID: 20820 - Posted: 04.20.2015
Mothers may influence the mood and behaviour of their babies through their breast milk, researchers say. There's growing evidence that mother's milk doesn't just affect the growth of a baby's body "but also areas of their brain that shape their motivations, their emotions, and therefore their behavioural activity," says Katie Hinde, an assistant professor of human evolutionary biology at Harvard University. In a paper published in the journal Evolution, Medicine and Public Health, Hinde and two other researchers propose a way in which the composition of breast milk could influence a baby's brain and behaviour. If food is scarce or there are a lot of predators around, it may be better for a mother to have a baby that is calmer and focuses on growing rather than one that is very active and playful, Hinde told CBC Radio's Quirks & Quarks in an interview that airs Saturday. It may be possible to influence a baby's activity level by changing the composition of the milk to affect the bacteria in the infant's gut, she added. Breast milk contains a lot of sugars that infants can't digest, but that feed bacteria that live in human intestines. Those bacteria don't just help digest food, said Hinde. "They can release chemical signals that travel to the infant's brain and shape neurodevelopment." ©2015 CBC/Radio-Canada
by Beth Mole Small doses of lead may have big impacts on reading and math scores, scientists report April 7 in Environmental Health. Researchers looked at third grade test scores and levels of lead in blood samples from 58,650 students in Chicago public schools. As little as 2 micrograms of lead per deciliter of blood was associated with lower reading and math scores. The Centers for Disease Control and Prevention recommends that anything above 5 micrograms per deciliter is of concern. The researchers estimate that childhood lead levels at or above 5 micrograms per deciliter of blood accounted for as many as 25 percent of the children in the study failing reading and math standardized tests. The findings confirm that lead exposure, even at low doses, is associated with poor school performance. © Society for Science & the Public 2000 - 2015
By Nicholas Bakalar Breathing problems during sleep may be linked to early mental decline and Alzheimer’s disease, a new study suggests. But treating apnea with a continuous positive airway pressure machine can significantly delay the onset of cognitive problems. In a group of 2,470 people, average age 73, researchers gathered information on the incidence of sleep apnea, a breathing disorder marked by interrupted breathing and snoring, and the incidence of mild cognitive impairment and Alzheimer’s disease. After adjusting for a range of variables, they found that people with disordered breathing during sleep became cognitively impaired an average of about 10 years sooner than those without the disorder. But compared with those whose sleep disorder was untreated, those using C.P.A.P. machines delayed the appearance of cognitive impairment by an average of 10 years — making their age of onset almost identical to those who had no sleep disorder at all. The lead author, Dr. Ricardo S. Osorio, a research professor of psychiatry at New York University, said the analysis, published online in Neurology, is an observational study that does not prove cause and effect. “But,” he added, “we need to increase the awareness that sleep disorders can increase the risk for cognitive impairment and possibly for Alzheimer’s. Whether treating sleep disorders truly slows the decline is still not known, but there is some evidence that it might.” © 2015 The New York Times Company
|By Cari Nierenberg and LiveScience Women who develop gestational diabetes early in their pregnancy have a higher chance of having a child with autism than women who don't develop the condition, a new study suggests. Researchers found that mothers-to-be who developed gestational diabetes — high blood sugar during pregnancy in women who have never had diabetes — by their 26th week of pregnancy were 63 percent more likely to have a child diagnosed with an autism spectrum disorder (ASD) compared with women who did not have gestational diabetes at any point during their pregnancy (and who also did not have type 2 diabetes prior to pregnancy). The finding does not mean that autism is common among children born to women who had gestational diabetes. "Autism is still rare," said study co-author Anny Xiang, a research scientist at Kaiser Permanente Southern California in Pasadena. The findings show that, although the risk of having a child with autism is still low among women who have gestational diabetes early in pregnancy (before 26 weeks), the study did find a relationship between these women and an increased risk that the child would have autism, Xiang said. The study, published today (April 14) in the Journal of the American Medical Association, looked at more than 320,000 children born in Southern California between 1995 and 2009. About 8 percent of the kids were born to mothers who had pregnancy-related diabetes, and 2 percent had mothers with type 2 diabetes. © 2015 Scientific American
By Neuroskeptic According to a large study just published in the Journal of Autism and Developmental Disorders, there’s no correlation between brain anatomy and self-reported autistic traits. Dutch researchers P. Cedric M. P. Koolschijn and colleagues looked at two samples of young Dutch adults: an ‘exploration’ sample of 204, and a separate ‘validation’ group of 304 individuals. Most of the participants did not have autism. The researchers looked for associations between various aspects of brain structure and autistic traits, using the AQ questionnaire, a popular self-report measure. Autistic traits are personality or behavior features similar to (but generally milder than) autism symptoms. For example, the first item on the AQ is “I prefer to do things with others rather than on my own.” If you disagree with that, you get a point. More points means more autistic traits. Koolschijn et al. used VBM, vertex-based cortical thickness analysis, and diffusion weighted imaging to explore different aspects of brain grey and white matter anatomy. However, although AQ scores were weakly correlated with the volume of a few brain areas in the exploration sample, none of these correlations were confirmed in the larger validation sample, suggesting that they were just false positives caused by the large number of multiple comparisons.
A study using mice has uncovered a possible cause of Alzheimer’s disease, and suggests that a drug currently being investigated in human clinical trials to treat cancer could prevent the illness. The research has been heralded as offering hope of finding new treatments for dementia, an illness that affects 850,000 people in the UK. The findings, by Duke University in America and published in the Journal of Neuroscience, are surprising, according to one of the authors, as they contradict current thinking on the disease. The research suggests that in mice with Alzheimer’s disease certain immune cells that normally protect the brain begin abnormally to consume an important nutrient called arginine. By blocking this process using the drug difluoromethylornithine (DFMO), memory loss and a buildup of sticky proteins known as brain plaques were prevented. The study used a type of mouse in which a number of important genes had been swapped to make the animal’s immune system more similar to a human’s. Senior author Carol Colton, professor of neurology at the Duke University School of Medicine, and a member of the Duke Institute for Brain Sciences, said: “If indeed arginine consumption is so important to the disease process, maybe we could block it and reverse the disease.” It was previously thought the brain releases molecules that ramp up the immune system, apparently damaging the brain, but the study found a heightened expression of genes associated with the suppression of the immune system. Author Matthew Kan said: “It’s surprising because [suppression of the immune system is] not what the field has been thinking is happening in AD [Alzheimer’s disease].” © 2015 Guardian News and Media Limited
Link ID: 20802 - Posted: 04.15.2015
Jon Hamilton There's new evidence that the brain's activity during sleep isn't random. And the findings could help explain why the brain consumes so much energy even when it appears to be resting. "There is something that's going on in a very structured manner during rest and during sleep," says Stanford neurologist Dr. Josef Parvizi, "and that will, of course, require energy consumption." For a long time, scientists dismissed the brain's electrical activity during rest and sleep as meaningless "noise." But then studies using fMRI began to reveal patterns suggesting coordinated activity. To take a closer look, Parvizi and a team of researchers studied three people awaiting surgery for epilepsy. These people spent several days with electrodes in their brains to help locate the source of their seizures. And that meant Parvizi's team was able to monitor the activity of small groups of brain cells in real time. "We wanted to know exactly what's going on during rest," Parvizi says, "and whether or not it reflects what went on during the daytime when the subject was not resting." In the study published online earlier this month in Neuron, the team first studied the volunteers while they were awake and answering simple questions like: Did you drive to work last week? "In order to answer yes or no, you retrieve a lot of facts; you retrieve a lot of visualized memories," Parvizi says. © 2015 NPR
By James Gallagher Health editor, BBC News website Those who were overweight had an 18% reduction in dementia, researchers found Being overweight cuts the risk of dementia, according to the largest and most precise investigation into the relationship. The researchers admit they were surprised by the findings, which run contrary to current health advice. The analysis of nearly two million British people, in the Lancet Diabetes & Endocrinology, showed underweight people had the highest risk. Dementia charities still advised not smoking, exercise and a balanced diet. Dementia is one of the most pressing modern health issues. The number of patients globally is expected to treble to 135 million by 2050. There is no cure or treatment, and the mainstay of advice has been to reduce risk by maintaining a healthy lifestyle. Yet it might be misguided. The team at Oxon Epidemiology and the London School of Hygiene and Tropical Medicine analysed medical records from 1,958,191 people aged 55, on average, for up to two decades. Their most conservative analysis showed underweight people had a 39% greater risk of dementia compared with being a healthy weight. But those who were overweight had an 18% reduction in dementia - and the figure was 24% for the obese. "Yes, it is a surprise," said lead researcher Dr Nawab Qizilbash. He told the BBC News website: "The controversial side is the observation that overweight and obese people have a lower risk of dementia than people with a normal, healthy body mass index. "That's contrary to most if not all studies that have been done, but if you collect them all together our study overwhelms them in terms of size and precision." Loss of tissue in a demented brain compared with a healthy one © 2015 BBC
By Ariana Eunjung Cha Autism has always been a tricky disorder to diagnose. There’s no such thing as a blood test, cheek swap or other accepted biological marker so specialists must depend on parent and teacher reports, observations and play assessments. Figuring out a child's trajectory once he or she is diagnosed is just as challenging. The spectrum is wide and some are destined to be on the mild end and be very talkative, sometimes almost indistinguishable from those without the disorder in some settings, while others will suffer from a more severe form and have trouble being able to speak basic words. Now scientists believe that they have a way to distinguish between those paths, at least in terms of language ability, in the toddler years using brain imaging. In an article published Thursday in the journal Neuron, scientists at the University of California-San Diego have found that children with autism spectrum disorder, or ASD, with good language outcomes have strikingly distinct patterns of brain activation as compared to those with poor language outcomes and typically developing toddlers. "Why some toddlers with ASD get better and develop good language and others do not has been a mystery that is of the utmost importance to solve," Eric Courchesne, one of the study’s authors and co-director of the University of California-San Diego's Autism Center, said in a statement. The images of the children in the study -- MRIs of the brain -- were taken at 12 to 29 months while their language was assessed one to two years later at 30 to 48 months.
By Megan Griffith-Greene The idea of playing a game to make you sharper seems like a no-brainer. That's the thinking behind a billion-dollar industry selling brain training games and programs designed to boost cognitive ability. But an investigation by CBC's Marketplace reveals that brain training games such as Lumosity may not make your brain perform better in everyday life. Lumosity Brain training games, such as Lumosity, are a billion-dollar industry. Many people are worried about maintaining their brain health and want to prevent a decline in their mental abilities. (CBC) Almost 15 per cent of Canadians over the age of 65 are affected by some kind of dementia. And many people of all ages are worried about maintaining their brain health and possibly preventing a decline in their mental abilities. "I don't think there's anything to say that you can train your brain to be cognitively better in the way that we know that we can train our bodies to be physically better," neuroscientist Adrian Owen told Marketplace co-host Tom Harrington. To test how effective the games are at improving cognitive function, Marketplace partnered with Owen, who holds the Canada Excellence Research Chair in Cognitive Neuroscience and Imaging at the Brain and Mind Institute at Western University. A group of 54 adults, including Harrington, did the brain training at least three times per week for 15 minutes or more over a period of between two and a half and four weeks. The group underwent a complete cognitive assessment at the beginning and end of the training to see if there had been any change as the result of the training program. ©2015 CBC/Radio-Canada.
Cari Romm “As humans, we can identify galaxies light-years away. We can study particles smaller than an atom,” President Barack Obama said in April 2013, “But we still haven’t unlocked the mystery of the three pounds of matter that sits between our ears.” The observation was part of the president’s announcement of the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative, an effort to fast-track the development of new technology that will help scientists understand the workings of the human brain and its diseases. With progress, though, comes a whole new set of ethical questions. Can drugs used to treat conditions like ADHD, for example, also be used to make healthy people into sharper, more focused versions of themselves—and should they? Can a person with Alzheimer’s truly consent to testing that may help scientists better understand their disease? Can brain scans submitted as courtroom evidence reveal anything about a defendant’s intent? Can a person with Alzheimer’s truly consent to testing that may help scientists better understand their disease? To address these questions, the Presidential Commission for the Study of Bioethical Issues, an independent advisory group, recently released the second volume of a report examining the issues that may arise as neuroscience advances. The commission outlined three areas it deemed particularly fraught: cognitive enhancement, consent, and the use of neuroscience in the legal system. © 2015 by The Atlantic Monthly Group
|By Simon Makin People can control prosthetic limbs, computer programs and even remote-controlled helicopters with their mind, all by using brain-computer interfaces. What if we could harness this technology to control things happening inside our own body? A team of bioengineers in Switzerland has taken the first step toward this cyborglike setup by combining a brain-computer interface with a synthetic biological implant, allowing a genetic switch to be operated by brain activity. It is the world's first brain-gene interface. The group started with a typical brain-computer interface, an electrode cap that can register subjects' brain activity and transmit signals to another electronic device. In this case, the device is an electromagnetic field generator; different types of brain activity cause the field to vary in strength. The next step, however, is totally new—the experimenters used the electromagnetic field to trigger protein production within human cells in an implant in mice. The implant uses a cutting-edge technology known as optogenetics. The researchers inserted bacterial genes into human kidney cells, causing them to produce light-sensitive proteins. Then they bioengineered the cells so that stimulating them with light triggers a string of molecular reactions that ultimately produces a protein called secreted alkaline phosphatase (SEAP), which is easily detectable. They then placed the human cells plus an LED light into small plastic pouches and inserted them under the skin of several mice. © 2015 Scientific American
By Jan Hoffman As adults age, vision deteriorates. One common type of decline is in contrast sensitivity, the ability to distinguish gradations of light to dark, making it possible to discern where one object ends and another begins. When an older adult descends a flight of stairs, for example, she may not tell the edge of one step from the next, so she stumbles. At night, an older driver may squint to see the edge of white road stripes on blacktop. Caught in the glare of headlights, he swerves. But new research suggests that contrast sensitivity can be improved with brain-training exercises. In a study published last month in Psychological Science, researchers at the University of California, Riverside, and Brown University showed that after just five sessions of behavioral exercises, the vision of 16 people in their 60s and 70s significantly improved. After the training, the adults could make out edges far better. And when given a standard eye chart, a task that differed from the one they were trained on, they could correctly identify more letters. “There’s an idea out there that everything falls apart as we get older, but even older brains are growing new cells,” said Allison B. Sekuler, a professor of psychology, neuroscience and behavior at McMaster University in Ontario, who was not involved in the new study. “You can teach an older brain new tricks.” The training improved contrast sensitivity in 16 young adults in the study as well, although the older subjects showed greater gains. That is partly because the younger ones, college students, already had reasonably healthy vision and there was not as much room for improvement. Before the training, the vision of each adult, young and older, was assessed. The exercises were fine-tuned at the beginning for each individual so researchers could measure improvements, said Dr.G. John Andersen, the project’s senior adviser and a psychology professor at the University of California, Riverside. © 2015 The New York Times Company
Cory Turner To survive, we humans need to be able to do a handful of things: breathe, of course. And drink and eat. Those are obvious. We're going to focus now on a less obvious — but no less vital — human function: learning. Because new research out today in the journal Science sheds light on the very building blocks of learning. Imagine an 11-month-old sitting in a high chair opposite a small stage where you might expect, say, a puppet show. Except this is a lab at Johns Hopkins University. Instead of a puppeteer, a researcher is rolling a red and blue striped ball down a ramp, toward a little wall at the bottom. Even babies seem to know the ball can't go through that wall, though not necessarily because they learned it. It's what some scientists call core knowledge — something, they say, we're born with. "Some pieces of knowledge are so fundamental in guiding regular, everyday interactions with the environment, navigating through space, reaching out and picking up an object, avoiding an oncoming object — those things are so fundamental to survival that they're really selected for by evolution," says Lisa Feigenson, a professor of psychological and brain sciences at Hopkins and one of the researchers behind this study. Which explains why the baby seems genuinely surprised when the ball rolls down the ramp and does go through the wall — thanks to some sleight of hand by the researchers: © 2015 NPR
Keyword: Development of the Brain
Link ID: 20756 - Posted: 04.04.2015
By Matt McFarland The individuals who have founded some of the most success tech companies are decidedly weird. Examine the founder of a truly innovative company and you’ll find a rebel without the usual regard for social customs. This begs the question, why? Why aren’t more “normal” people with refined social graces building tech companies that change the world? Why are only those on the periphery reaching great heights? If you ask tech investor Peter Thiel, the problem is a social environment that’s both powerful and destructive. Only individuals with traits reminiscent of Asperger’s Syndrome, which frees them from an attachment to social conventions, have the strength to create innovative businesses amid a culture that discourages daring entrepreneurship. “Many of the more successful entrepreneurs seem to be suffering from a mild form of Asperger’s where it’s like you’re missing the imitation, socialization gene,” Thiel said Tuesday at George Mason University. “We need to ask what is it about our society where those of us who do not suffer from Asperger’s are at some massive disadvantage because we will be talked out of our interesting, original, creative ideas before they’re even fully formed. Oh that’s a little bit too weird, that’s a little bit too strange and maybe I’ll just go ahead and open the restaurant that I’ve been talking about that everyone else can understand and agree with, or do something extremely safe and conventional.” An individual with Asperger’s Syndrome — a form of autism — has limited social skills, a willingness to obsess and an interest in systems. Those diagnosed with Asperger’s Syndrome tend to be unemployed or underemployed at rates that far exceed the general population. Fitting into the world is difficult.
Link ID: 20755 - Posted: 04.04.2015
Emily Hodgkin As a nation we think we understand autism. Since the first discovery of the condition just over 70 years ago awareness of autism has continued to grow. Despite this, 87 per cent of people affected by autism think the general public has a bad understanding of the condition. Many of the common myths surrounding autism have been debunked - including the perception that people with autism can’t hold a job. But only 15 per cent of adults in the UK with autism are in full-time employment, while 61 per cent of people with autism currently not in employment say they want to work. Research suggests that employers are missing out on abilities that people on the autism spectrum have in greater abundance – such as heightened abilities in pattern recognition and logical reasoning, as well as a greater attention to detail. Mark Lever, chief executive of the National Autistic Society (NAS) said: "It's remarkable that awareness has increased so much since the NAS was set up over 50 years ago, a time when people with the condition were often written off and hidden from society. But, as our supporters frequently tell us and the poll confirms, there is still a long way to go before autism is fully understood and people with the condition are able to participate fully in their community. All too often we still hear stories of families experiencing judgemental attitudes or individuals facing isolation or unemployment due to misunderstandings or myths around autism.” There are around 700,000 autistic people in the UK – more than 1 in a 100. So as it's more common than perhaps expected, what other myths still exist? © independent.co.uk
Link ID: 20754 - Posted: 04.04.2015
Alison Abbott Historian of psychology Douwe Draaisma knows well how to weave science, history and literature into irresistible tales. Forgetting, his latest collection of essays around the theme of memory, is — like his successful Nostalgia Factory (Yale University Press, 2013) — hard to put down. His vivid tour through the history of memory-repression theories brings home how dangerous and wrong, yet persistent, were the ideas of Sigmund Freud and his intellectual heirs. Freud thought that traumatic memories and shameful thoughts could be driven from the consciousness, but not forgotten. They would simmer in the unconscious, influencing behaviour. He maintained that forcing them out with psychoanalysis, and confronting patients with them, would be curative. Draaisma relates the case of an 18-year-old whom Freud dubbed Dora, diagnosed in 1900 with 'hysteria'. Dora's family refused to believe that the husband of her father's mistress had made sexual advances to her. Among other absurdities, Freud told Dora that her nervous cough reflected her repressed desire to fellate the man. Dora broke off the therapy, which Freud saw as proof of his theory. He thought that patients will naturally resist reawakening painful thoughts. What Dora did not buy, plenty of others did. Psychoanalysis boomed, becoming lucrative. Its principles were adopted in the 1990s by an unlikely alliance of lawyers and some feminists, who argued that repressed memories of childhood abuse could be recovered with techniques such as hypnosis, and used as evidence in court. Many judges went along with it; the rush of claims cast a shadow over genuine cases of abuse, Draaisma points out. We now know from studies of post-traumatic stress disorder that traumatic memories are impossible to repress. They flood into the conscious mind in horrifying flashbacks. © 2015 Macmillan Publishers Limited
Keyword: Learning & Memory
Link ID: 20747 - Posted: 04.02.2015