Chapter 13. Memory, Learning, and Development
Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.
Alison Abbott The octopus genome offers clues to how cephalopods evolved intelligence to rival the craftiest vertebrates. With its eight prehensile arms lined with suckers, camera-like eyes, elaborate repertoire of camouflage tricks and spooky intelligence, the octopus is like no other creature on Earth. Added to those distinctions is an unusually large genome, described in Nature1 on 12 August, that helps to explain how a mere mollusc evolved into an otherworldly being. “It’s the first sequenced genome from something like an alien,” jokes neurobiologist Clifton Ragsdale of the University of Chicago in Illinois, who co-led the genetic analysis of the California two-spot octopus (Octopus bimaculoides). The work was carried out by researchers from the University of Chicago, the University of California, Berkeley, the University of Heidelberg in Germany and the Okinawa Institute of Science and Technology in Japan. The scientists also investigated gene expression in twelve different types of octopus tissue. “It’s important for us to know the genome, because it gives us insights into how the sophisticated cognitive skills of octopuses evolved,” says neurobiologist Benny Hochner at the Hebrew University of Jerusalem in Israel, who has studied octopus neurophysiology for 20 years. Researchers want to understand how the cephalopods, a class of free-floating molluscs, produced a creature that is clever enough to navigate highly complex mazes and open jars filled with tasty crabs. © 2015 Nature Publishing Group
Ashley Yeager A mouse scurries across a round table rimmed with Dixie cup–sized holes. Without much hesitation, the rodent heads straight for the hole that drops it into a box lined with cage litter. Any other hole would have led to a quick fall to the floor. But this mouse was more than lucky. It had an advantage — human glial cells were growing in its brain. Glia are thought of as the support staff for the brain’s nerve cells, or neurons, which transmit and receive the brain’s electrical and chemical signals. Named for the Greek term for “glue,” glia have been known for nearly 170 years as the cells that hold the brain’s bits together. Some glial cells help feed neurons. Other glia insulate nerve cell branches with myelin. Still others attack brain invaders responsible for infection or injury. Glial cells perform many of the brain’s most important maintenance jobs. But recent studies suggest they do a lot more. Glia can shape the conversation between neurons, speeding or slowing the electrical signals and strengthening neuron-to-neuron connections. When scientists coaxed human glia to grow in the brains of baby mice, the mice grew up to be supersmart, navigating tabletops full of holes and mastering other tasks much faster than normal mice. This experiment and others suggest that glia may actually orchestrate learning and memory, says neuroscientist R. Douglas Fields. “Glia aren’t doing vibrato. That’s for the neurons,” says Fields, of the National Institute of Child Health and Human Development in Bethesda, Md. “Glia are the conductors.” © Society for Science & the Public 2000 - 2015
Could taking iodine pills in pregnancy help to raise children’s IQ? Some researchers suggest women in the UK should take such supplements, but others say the evidence is unclear, and that it could even harm development. Iodine is found in dairy foods and fish, and is used in the body to make thyroid hormone, which is vital for brain development in the womb. In some parts of the world, such as inland areas where little fish is consumed or the soil is low in iodine, severe deficiencies can markedly lower intelligence in some people. In most affected areas, iodine is now added to salt. The UK was not thought to need this step, but in 2013 a large study of urine samples from pregnant women found that about two-thirds had mild iodine deficiency, and that the children of those with the lowest levels had the lowest IQs. Now another team has combined data from this study with other data to calculate that if all women in the UK were given iodine supplements from three months before pregnancy until they finished breastfeeding, average IQ would increase by 1.2 points per child. And the children of mothers who were most iodine deficient would probably benefit more, says Kate Jolly of the University of Birmingham, who was involved in the study. “We are talking about very small differences but on a population basis it could mean quite a lot,” she says. The team calculated that providing these iodine supplements would be worth the cost to the UK’s National Health Service because it would boost the country’s productivity. © Copyright Reed Business Information Ltd.
April Dembosky Developers of a new video game for your brain say theirs is more than just another get-smarter-quick scheme. Akili, a Northern California startup, insists on taking the game through a full battery of clinical trials so it can get approval from the Food and Drug Administration — a process that will take lots of money and several years. So why would a game designer go to all that trouble when there's already a robust market of consumers ready to buy games that claim to make you smarter and improve your memory? Think about all the ads you've heard for brain games. Maybe you've even passed a store selling them. There's one at the mall in downtown San Francisco — just past the cream puff stand and across from Jamba Juice — staffed on my visit by a guy named Dominic Firpo. "I'm a brain coach here at Marbles: The Brain Store," he says. Brain coach? "Sounds better than sales person," Firpo explains. "We have to learn all 200 games in here and become great sales people so we can help enrich peoples' minds." He heads to the "Word and Memory" section of the store and points to one product that says it will improve your focus and reduce stress in just three minutes a day. "We sold out of it within the first month of when we got it," Firpo says. The market for these "brain fitness" games is worth about $1 billion and is expected to grow to $6 billion in the next five years. Game makers appeal to both the young and the older with the common claim that if you exercise your memory, you'll be able to think faster and be less forgetful. Maybe bump up your IQ a few points. "That's absurd," says psychology professor Randall Engle from the Georgia Institute of Technology. © 2015 NPR
Tina Hesman Saey Memory Transfer Seen — Experiments with rats, showing how chemicals from one rat brain influence the memory of an untrained animal, indicate that tinkering with the brain of humans is also possible. In the rat tests, brain material from an animal trained to go for food either at a light flash or at a sound signal was injected into an untrained rat. The injected animals then "remembered" whether light or sound meant food. — Science News Letter, August 21, 1965 Update: After this report, scientists from eight labs attempted to repeat the memory transplants. They failed, as they reported in Science in 1966. Science fiction authors and futurists often predict that a person’s memories might be transferred to another person or a computer, but the idea is likely to remain speculation, says neuroscientist Eric Kandel, who won a Nobel Prize in 2000 for his work on memory. Brain wiring is too intricate and complicated to be exactly replicated, and scientists are still learning about how memories are made, stored and retrieved. W. L. Byrne et al. Technical Comments: Memory Transfer. Science Vol. 153, August 5, 1966, p. 658. doi:10.1126/science.153.3736.658 © Society for Science & the Public 2000 - 2015
Keyword: Learning & Memory
Link ID: 21271 - Posted: 08.08.2015
By Christian Jarrett One of the saddest things about loneliness is that it leads to what psychologists call a “negative spiral.” People who feel isolated come to dread bad social experiences and they lose faith that it’s possible to enjoy good company. The usual result, as Melissa Dahl recently noted, is more loneliness. This hardly seems adaptive, but experts say it’s because we’ve evolved to enter a self-preservation mode when we’re alone. Without the backup of friends and family, our brains become alert to threat, especially the potential danger posed by strangers. Until now, much of the evidence to support this account has come from behavioral studies. For example, when shown a video depicting a social scene, lonely people spend more time than others looking at signs of social threat, such as a person being ignored by their friends or one person turning their back on another. Unpublished work also shows that lonely people’s attention seems to be grabbed more quickly by words that pertain to social threat, such as rejected or unwanted. Now the University of Chicago’s husband-and-wife research team of Stephanie and John Cacioppo — leading authorities on the psychology and neuroscience of loneliness — have teamed up with their colleague, Stephen Balogh, to provide the first evidence that lonely people’s brains, compared to the non-lonely, are exquisitely alert to the difference between social and nonsocial threats. The finding, reported online in the journal Cortex, supports their broader theory that, for evolutionary reasons, loneliness triggers a cascade of brain-related changes that put us into a socially nervous, vigilant mode. The researchers used a loneliness questionnaire to recruit 38 very lonely people and 32 people who didn’t feel lonely (note that loneliness was defined here as the subjective feeling of isolation, as opposed to the number of friends or close relatives one has). Next, the researchers placed an electrode array of 128 sensors on each of the participants’ heads, allowing them to record the participants’ brain waves using an established technique known as electro-encephalography (EEG) that’s particularly suited to measuring brain activity changes over very short time periods. © 2015, New York Media LLC.
Laura Sanders A type of brain cell formerly known for its supporting role has landed a glamorous new job. Astrocytes, a type of glial cell known to feed, clean and guide the growth of their flashier nerve cell neighbors, also help nerve cells send electrical transmissions, scientists report in the Aug. 5 Journal of Neuroscience. The results are the latest in scientists’ efforts to uncover the mysterious and important ways in which cells other than nerve cells keep the nervous system humming. Astrocytes deliver nutrients to nerve cells, flush waste out of the brain (SN: 9/22/12) and even help control appetite (SN: 6/28/14). The latest study suggests that these star-shaped cells also help electrical messages move along certain nerve cells’ message-sending axons, a job already attributed to other glial cells called oligodendrocytes and Schwann cells. Courtney Sobieski of Washington University School of Medicine in St. Louis and colleagues grew individual rat nerve cells in a single dish that contained patches of astrocytes. Some nerve cells grew on the patches; others did not. The nerve cells deprived of astrocyte contact showed signs of sluggishness. The researchers think that astrocytes guide nerve cell growth in a way that enables the nerve cells to later fire off quick and precise messages. It’s not clear how the astrocytes do that, but the results suggest that proximity is the key: Astrocytes needed to be close to the nerve cell to help messages move. © Society for Science & the Public 2000 - 2015
By Roni Caryn Rabin For years experts have urged physicians to screen infants and toddlers for autism in order to begin treatment as early as possible. But now an influential panel of experts has concluded there is not enough evidence to recommend universal autism screening of young children. The findings, from a draft proposal by the U.S. Preventive Services Task Force published Monday, are already causing consternation among specialists who work with autistic children. “I was in a meeting when I read this, and I started feeling like I’d have chest pain,” said Dr. Susan E. Levy, a pediatrician who helped write the American Academy of Pediatrics guidelines urging universal screening of all babies, with standardized screening tools at both 18 and 24 months. “I would hate to see people stop screening.” Dr. David Grossman, a pediatrician and vice chairman of the U.S. Preventive Services Task Force, emphasized that the panel’s draft proposal was a call for more research and not intended to change practices. About half of all pediatricians routinely screen toddlers for autism. “This doesn’t mean ‘don’t screen.’ ” Dr. Grossman said. “It means there is not enough evidence to make a recommendation.” Dr. Grossman also noted that the panel’s conclusion applied only to routine screening of healthy children without symptoms. A child displaying symptoms associated with autism should always be evaluated, he said. “If a parent comes in and says, ‘My child isn’t looking at me,’ that’s not a screening,” Dr. Grossman said. “You hear that as a doctor and you say, ‘That needs to be looked at,’ and you embark on a series of tests.” Despite those reassurances, autism experts worry that the panel’s lack of support for early autism screening could undermine efforts to identify and treat children as early as possible. The task force is an independent panel of experts in prevention and primary care appointed by the federal Department of Health and Human Services. The task force wields enormous influence in the medical community. In 2009, the panel issued controversial screening guidelines for breast cancer, stating that routine mammograms should start at 50 rather than 40. © 2015 The New York Times Company
Link ID: 21262 - Posted: 08.04.2015
Cerebral palsy, the most common cause of physical disability in children, has long been thought to result from brain injury in the fetus. But new Canadian research is challenging that notion, finding that at least one in 10 cases likely has an underlying genetic cause. So ingrained has medical dogma been around the root causes of cerebral palsy that "when I showed the results to our clinical geneticists, initially they didn't believe it," he said. About two in every 1,000 babies born are affected by cerebral palsy. An estimated 50,000 Canadian children and adults have the condition, which leads to varying degrees of motor impairment, including muscle spasticity and involuntary movements. Symptoms can include epilepsy as well as learning, speech, hearing and visual impairments. Some with the disorder are mildly affected, while others can't walk or communicate. Traditionally, cerebral palsy was believed to be caused by a stroke or infection of the brain in the developing fetus, or by birth asphyxia — a lack of oxygen to the infant during delivery. But genetic testing of a group of affected children from across Canada found that in 10 per cent of cases, structural changes to the DNA appear to have given rise to the condition. The research team, which includes physicians at the McGill University Health Centre in Montreal, performed genome sequencing tests on 115 children with cerebral palsy and their parents. ©2015 CBC/Radio-Canada.
Steve Connor A computer game designed by neuroscientists has helped patients with schizophrenia to recover their ability to carry out everyday tasks that rely on having good memory, a study has found. Patients who played the game regularly for a month were four times better than non-players at remembering the kind of things that are critical for normal, day-to-day life, researchers said. The computer game was based on scientific principles that are known to “train” the brain in episodic memory, which helps people to remember events such as where they parked a car or placed a set of keys, said Professor Barbara Sahakian of Cambridge University, the lead author of the study. People recovering from schizophrenia suffer serious lapses in episodic memory which prevent them from returning to work or studying at university, so anything that can improve the ability of the brain to remember everyday events will help them to lead a normal life, Professor Sahakian said. Schizophrenia affects about one in every hundred people and results in hallucinations and delusions (Rex) Schizophrenia affects about one in every hundred people and results in hallucinations and delusions (Rex) “This kind of memory is essential for everyday learning and everything we do really both at home and at work. We have formulated an iPad game that could drive the neural circuitry behind episodic memory by stimulating the ability to remember where things were on the screen,” Professor Sahakian said. © independent.co.uk
Michael Sullivan It's 5:45 in the morning, and in a training field outside Siem Reap, home of Angkor Wat, Cambodia's demining rats are already hard at work. Their noses are close to the wet grass, darting from side to side, as they try to detect explosives buried just beneath the ground. Each rat is responsible for clearing a 200-square-meter (239-square-yard) patch of land. Their Cambodian supervisor, Hulsok Heng, says they're good at it. "They are very good," he says. "You see this 200 square meters? They clear in only 30 minutes or 35 minutes. If you compare that to a deminer, maybe two days or three days. The deminer will pick up all the fragmentation, the metal in the ground, but the rat picks up only the smell of TNT. Not fragmentation or metal or a nail or a piece of crap in the ground." That's right: Someone using a metal-detecting machine will take a lot longer to detect a land mine than a rat using its nose. There's plenty of work for the rats here in Cambodia. The government estimates there are 4 million to 6 million land mines or other pieces of unexploded ordnance — including bombs, shells and grenades — littering the countryside, remnants of decades of conflict. Neighboring Vietnam and Laos also have unexploded ordnance left over from the Vietnam War. Dozens of people are killed or maimed in the region every year — and there's a financial toll as well, since the presence of these potentially deadly devices decreases the amount of land available to farmers. © 2015 NPR
By Robert Gebelhoff Just in case sea snails aren't slow enough, new research has found that they get more sluggish when they grow old — and the discovery is helping us to understand how memory loss happens in humans. It turns out that the sea snail, which has a one-year lifespan, is actually a good model to study nerve cells and how the nervous system works in people. How neurons work is fundamentally identical in almost all animals, and the simplicity of the snail's body gives researchers the chance to view how different the system works more directly. "You can count the number of nerve cells that are relevant to a reflex," said Lynne Fieber, a professor at the University of Miami who leads research with the snails at the school. She and a team of researchers have been using the slimy little critters to learn how nerve cells respond to electric shock. They "taught" the snails to quickly contract their muscle tails by administering electric shocks and then poking the tails, a process called "sensitization." They then studied the responses at various ages. The scientists, whose work was published this week in the journal PlOS One, found that as the senior citizen specimens do not learn to contract from the shock very well. As the snails grow older, their tail startle reflex lessened, and then disappeared. So I guess you could say the frail snails' tails fail to avail (okay, I'll stop).
By Bret Stetka The brain is extraordinarily good at alerting us to threats. Loud noises, noxious smells, approaching predators: they all send electrical impulses buzzing down our sensory neurons, pinging our brain’s fear circuitry and, in some cases, causing us to fight or flee. The brain is also adept at knowing when an initially threatening or startling stimulus turns out to be harmless or resolved. But sometimes this system fails and unpleasant associations stick around, a malfunction thought to be at the root of post-traumatic stress disorder (PTSD). New research has identified a neuronal circuit responsible for the brain’s ability to purge bad memories, findings that could have implications for treating PTSD and other anxiety disorders. Like most emotions, fear is neurologically complicated. But previous work has consistently implicated two specific areas of the brain as contributing to and regulating fear responses. The amygdala, two small arcs of brain tissue deep beneath our temples, is involved in emotional reactions, and it flares with activity when we are scared. If a particular threat turns out to be harmless, a brain region behind the forehead called the prefrontal cortex steps in and the fright subsides. Our ability to extinguish painful memories is known to involve some sort of coordinated effort between the amygdala and the prefrontal cortex. The new study, led by Andrew Holmes at the National Institutes of Health, however, confirms that a working connection between the two brain regions is necessary to do away with fear. Normally mice that repeatedly listen to a sound previously associated with a mild foot shock will learn that on its own the tone is harmless, and they will stop being afraid. Using optogenetic stimulation technology, or controlling specific neurons and animal behavior using light, the authors found that disrupting the amygdala–prefrontal cortex connection prevents mice from overcoming the negative association with the benign tone. In neurobiology speak, memory “extinction” fails to occur. They also found that the opposite is true—that stimulating the circuit results in increased extinction of fearful memories. © 2015 Scientific American
By Ariana Eunjung Cha Think you have your hands full making sure your baby is fed and clean and gets enough sleep? Here's another thing for the list: developing your child's social skills by the way you talk. People used to think that social skills were something kids were born with, not taught. But a growing body of research shows that the environment a child grows up in as an infant and toddler can have a major impact on how they interact with others as they get older. And it turns out that a key factor may be the type of language they hear around them, even at an age when all they can do is babble. Psychologists at the University of York observed 40 mothers and their babies at 10, 12, 16 and 20 months and logged the kind of language mothers used during play. They were especially interested in "mind-related comments," which include inferences about what someone is thinking when a behavior or action happens. Elizabeth Kirk, a lecturer at the university who is the lead author of the study, published in the British Journal of Developmental Psychology on Monday, gave this as an example: If an infant has difficulty opening a door on a toy, the parent might comment that the child appears "frustrated." Then researchers revisited the children when they were 5 or 6 years of age and assessed their socio-cognitive ability. The test involved reading a story and having the children answer comprehension questions that show whether they understood the social concept -- persuasion, joke, misunderstanding, white lies, lies, and so forth -- that was represented.
Tara Haelle To tell if a baby has been injured or killed by being shaken, the courts use three hallmark symptoms: Bleeding and swelling in the brain and retinal bleeding in the eyes. Along with other evidence, those standards are used to convict caregivers of abusive head trauma, both intentional and unintentional, that can result in blindness, seizures, severe brain damage or death. But in recent years a small cadre of experts testifying for the defense in cases across the country has called into question whether those symptoms actually indicate abuse. Though they are in the minority – disputing the consensus of child abuse experts, pediatricians and an extensive evidence base – they have gained traction in the media and in courtrooms by suggesting that shaking a child cannot cause these injuries. Instead, they argue that undiagnosed medical conditions, falls or other accidents are the cause. So researchers have developed and validated a tool doctors can use to distinguish between head injuries resulting from abuse and those from accidents or medical conditions. The method, described in the journal Pediatrics Monday, asks doctors to check for six other injuries, each of which increases the likelihood that a head injury resulted from severe shaking, blunt force or both. "It is vitally important that abuse head trauma is diagnosed accurately so that the team looking after the child can ensure that they receive appropriate support and are protected from further harm," lead study author Laura Elizabeth Cowley, a PhD student at the Cardiff University School of Medicine in the U.K., said in an email. "However, it is also important that accidental head injury cases are not wrongly diagnosed as abusive," she continues, "because this can have devastating consequences for the families involved." © 2015 NPR
By Katie Free Shouting during a nightmare. Struggling to balance a checkbook. A weakened sense of smell. Hallucinations. Chronic constipation. This bizarre mix of symptoms often stumps doctors, but they are some of the telltale signs of Lewy body dementia—the second most common type (after Alzheimer's disease), affecting an estimated 1.4 million Americans. Lewy bodies are protein clumps that kill neurons. Depending on where they cluster in the brain, they can cause either Parkinson's disease or Lewy body dementia, although the two conditions tend to overlap as they progress. Lewy body dementia is more difficult to diagnose and treat, in part because the earliest warning signs have remained unknown. Now a new study finds that certain sensory and motor symptoms can help predict who will acquire the disease, paving the way for targeted studies. Researchers at the Center for Advanced Research in Sleep Medicine (which is associated with the University of Montreal) and at McGill University followed 89 patients with a history of acting out their dreams—not sleepwalking but moving or vocalizing in bed during rapid eye movement (REM) sleep. The failure to suppress such nighttime activity can be an early sign that something is going wrong in the brain; past studies have shown that up to 80 percent of patients who act out their dreams will eventually develop some form of neurodegeneration. Over 10 years the McGill researchers carefully tracked the patients' other potential symptoms of neural disease, such as mild cognitive impairment, depression and movement problems. They found a cluster of symptoms—abnormal color vision, loss of smell and motor dysfunction—that doubled the chance that a person with the REM sleep disorder would develop Parkinson's or Lewy body dementia within three years, according to the study published in February in Neurology. © 2015 Scientific American
Link ID: 21237 - Posted: 07.30.2015
By Neuroskeptic According to British biochemist Donald R. Forsdyke in a new paper in Biological Theory, the existence of people who seem to be missing most of their brain tissue calls into question some of the “cherished assumptions” of neuroscience. I’m not so sure. Forsdyke discusses the disease called hydrocephalus (‘water on the brain’). Some people who suffer from this condition as children are cured thanks to prompt treatment. Remarkably, in some cases, these post-hydrocephalics turn out to have grossly abnormal brain structure: huge swathes of their brain tissue are missing, replaced by fluid. Even more remarkably, in some cases, these people have normal intelligence and display no obvious symptoms, despite their brains being mostly water. This phenomenon was first noted by a British pediatrician called John Lorber. Lorber never published his observations in a scientific journal, although a documentary was made about them. However, his work was famously discussed in Science in 1980 by Lewin in an article called “Is Your Brain Really Necessary?“. There have been a number of other more recent published cases. Forsdyke argues that such cases pose a problem for mainstream neuroscience. If a post-hydrocephalic brain can store the same amount of information as a normal brain, he says, then “brain size does not scale with information quantity”, therefore, “it would seem timely to look anew at possible ways our brains might store their information.”
The eyes may be windows to the mind, but for children with autism, the body is the better communicator. They are just as good at reading emotions in body language as those without autism. The finding challenges the commonly held notion that children with autism have difficulty reading emotions. This may have arisen from studies focusing on whether people with the condition can interpret emotions from just the face or eyes, says Candida Peterson at the University of Queensland in Australia. “Looking at a face is in itself a problem,” says Peterson. “Autistic children and adults don’t like making eye contact,” she adds, as this requires a close encounter with another person. Reading body language, by contrast, can be done from a distance. In the study, children aged 5 to 12 were shown photos of adults with blurred faces posing in ways to convey happiness, sadness, anger, fear, disgust and surprise. Those with autism were just as good as those without at recognising the emotions. But this is only part of the picture. People with autism also have difficulty changing their behaviour in response to others’ emotions, says Julie Grezes at INSERM’s Laboratory of Cognitive Neurosciences in Paris, France. When most people recognise that someone is experiencing a certain emotion, they are able to put themselves in their place to understand why they might be feeling that way. People with autism are known to struggle with this. Now we know that they can read body language, says Peterson, we can look for ways to help them link certain cues to what the other person might be thinking and feeling. She and her colleagues now plan to test how good children with autism are at reading body language cues in real-life interactions, in particular when they are faced with individuals in extremely emotional states. Journal reference: Journal of Experimental Child Psychology, doi.org/6dp © Copyright Reed Business Information Ltd.
Link ID: 21225 - Posted: 07.27.2015
By Jane E. Brody Barrett Treadway, now 3½, has never been the best of sleepers, but her sleep grew increasingly worse in the last year and a half. She gets up several times a night, often climbs into her parents’ bed and creates havoc with their nights. “We’ve known for a long time that she snores, but until a mother-daughter trip in May when we shared a bed, I didn’t realize that this was not simply snoring,” her mother, Laura, told me. “She repeatedly stopped breathing, then started again with a loud snort that often woke her up and kept me up all night.” Barrett has sleep apnea, a condition most often diagnosed in adults and usually associated with obesity. But neither of those attributes describes Barrett, who is young and lithe, although the condition is somewhat more common in overweight children. In most cases, the problem results when, during sleep, the child’s airway is temporarily obstructed by enlarged tonsils or adenoids or both — lymphoid tissues in the back of the throat — hence the name obstructive sleep apnea. When breathing stops for 10 or more seconds, the rising blood level of carbon dioxide prompts the brain to take over and restart breathing, typically accompanied by a loud snore or snort. Rarely, a child may have what is called central sleep apnea, in which the brain temporarily fails to signal the muscles that control breathing. Experts say that between 1 percent and 3 percent of children have sleep apnea that, if untreated, can disrupt far more than a family’s restful nights. Affected children simply do not get enough restorative sleep to assure normal development. If not corrected, the condition can result in hyperactivity and attention problems in school that are often mistaken for attention deficit hyperactivity disorder (A.D.H.D.) and sometimes mistreated with a stimulant that only makes matters worse. © 2015 The New York Times Company
Alexandra Sims Intelligent people are not only smarter than the average person - it seems they could also live longer as well. A study by the London School of Economics found that smarter siblings are more likely to outlive their less clever brothers and sisters, with genetics accounting for 95 per cent of the connection between intelligence and life span. The scientists examined the differences in longevity between identical twins, who share all of their genes and non-identical twins, who on average share half of their genes. Writing in the International Journal of Epidemiology, scientists noted the difference in intellect between the twins and the age at which they died. Focusing on three different twin studies from Sweden, Denmark and the United States the researchers examined sets of twins for whom both intelligence and age of death had been recorded in pairs where at least one of the twins had died. In both types of twins it was found that the smarter of the two lived longer, but this effect was far more prominent in non-identical twins. Rosalind Arden, a research associate at the LSE, told The Times that "the association between top jobs and longer lifespans is more a result of genes than having a big desk.” She added though that the research does not mean parents can "deduce your child’s likely lifespan from how he or she does in their exams this summer”.