Chapter 13. Memory, Learning, and Development
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By Nicholas Bakalar Treating pregnant women for depression may benefit not just themselves but their babies as well. A study, in the May issue of Obstetrics & Gynecology, included 7,267 pregnant women, of whom 831 had symptoms of depression. After controlling for maternal age, race, income, body mass index and other health and behavioral characteristics, the researchers found that depressive symptoms were associated with a 27 percent increased relative risk of preterm birth (less than 37 weeks of gestation), an 82 percent increased risk of very preterm birth (less than 32 weeks of gestation), and a 28 percent increased risk of having a baby small for gestational age. They also found that among those who were treated with antidepressants for depression — about a fifth of those with the diagnosis — there was no association with increased risk for any of these problems. But they acknowledge that this group was quite small, which limits the power to draw conclusions. Still, the lead author, Dr. Kartik K. Venkatesh, a clinical fellow in obstetrics and gynecology at Harvard, said that it was important to screen mothers for depression, not only for their health but for that of their babies. “By screening early in pregnancy, you could identify those at higher risk and counsel them about the importance of treatment,” he said. “Treating these women for depression may have real benefits.” © 2016 The New York Times Company
by Laura Sanders Some researchers believe that when memories are called to mind, they enter a fragile, wobbly state during which they are vulnerable to being weakened or changed. One way to erode old memories is to learn something new just after recalling the older memory, scientists reported in 2003 (SN: 10/11/2003, p. 228). But that result itself is wobbly, scientists report April 25 in the Proceedings of the National Academy of Sciences. In an attempt to replicate the original finding, experimental psychologist Tom Hardwicke of University College London and colleagues didn’t see any memory alterations in people who learned a new sequence of finger taps shortly after recalling an old sequence. Nor did the researchers turn up signs of this memory interference in other tests. The new study focused specifically on new learning, but the findings cast suspicion on the legitimacy of other ways to interfere with people’s memories, Hardwicke says. Approaches such as brain stimulation or drugs might also be flawed, the researchers argue. © Society for Science & the Public 2000 - 2016
Keyword: Learning & Memory
Link ID: 22141 - Posted: 04.26.2016
It was December 2012 when the country learned about the massacre at Sandy Hook Elementary School, that left 20 children dead at the hands of 20-year-old shooter Adam Lanza. After the shock and the initial grief came questions about how it could have happened and why. Reports that Adam Lanza may have had some form of undiagnosed mental illness surfaced. The tragedy drove Liza Long to write a blog post on that same day, titled "I Am Adam Lanza's Mother." She wasn't Lanza's mom, but she was raising a child with a mental disorder. Her 13-year-old son had violent rages on a regular basis. He was in and out of juvenile detention. He had threatened to kill her. She detailed all this in her essay that took off online. Now, four years later, her son is speaking out too. This week on For The Record: a mother, a son and life on the edge of bipolar disorder. Eric Walton, Liza Long's son, is now a 16-year-old high school sophomore in Boise, Idaho. After a series of misdiagnoses, he's been diagnosed with bipolar disorder. But four years ago, he didn't know much about his condition. "I knew that there were times when I would have rages, didn't like them. I knew that I wanted them to stop," Walton says. Except he felt a loss of control in those moments. He describes the onset of these rages as a "blackout" of sorts. "I would start getting angry," he says. "Then it's like being trapped inside a box inside your own head. It was like a television on the wall that shows you what you're seeing. You can feel everything, but you no longer have the video game controller to control your own body." Walton's mom says when Eric would get into those states, "he would express a lot of suicidal thoughts, and hearing him just say, 'I want to die, I just want to end it.'" Then, two days before the Newtown shooting, Eric Walton had another episode. © 2016 npr
By Lisa L. Lewis On Tuesday, U.S. News and World Report released its annual public high-school rankings, with the School for the Talented and Gifted in Dallas earning the top spot for the fifth year in a row. The rankings are based on a wealth of data, including graduation rates and student performance on state proficiency tests and advanced exams, as well as other relevant factors—like the percentage of economically disadvantaged students the schools serve. But there’s one key metric that isn’t tracked despite having a proven impact on academic performance: school start times. First-period classes at the School for the Talented and Gifted start at 9:15 a.m. That’s unusually late compared to other schools but is in keeping with the best practices now recommended by public health experts. Teens require more sleep than adults and are hardwired to want to sleep in. Eight hours a night may be the goal for adults, but teens need between 8.5–9.5 hours, according to the American Academy of Pediatrics. Unfortunately, few teens meet that minimum: Studies show that two out of three high school students get less than eight hours of sleep, with high school seniors averaging less than seven hours. Sure, kids could go to bed earlier. But their bodies are set against them: Puberty makes it hard for them to fall asleep before 11 p.m. When combined with too-early start times, the result is sleep deprivation.
By Clare Wilson People who develop schizophrenia may have been born with brains with a different structure. The finding adds further support to the idea that genetics can play a key role in schizophrenia, which involves delusions and hallucinations and is often a lifelong condition once it develops. Schizophrenia has been the subject of a fierce nature-versus-nurture debate: childhood abuse is linked with a raised risk of the condition, but 108 genes have been implicated, too. Probing the biology of schizophrenia is difficult because brain tissue sampled from people with the condition is rarely available to study. Kristen Brennand of the Icahn School of Medicine at Mount Sinai in New York and her colleagues got around this by taking skin cells from 14 people with schizophrenia, and reprogramming them into stem cells and then nerve cells. They found that on average these nerve cells had lower levels of a signalling molecule called miR-9 than similar cells developed from people who do not have schizophrenia. A small string of nucleic acids, miR-9 can change the activity of certain genes and is known to play a role in how neurons develop in the fetus. In further experiments, Brennand’s team showed that miR-9 might also affect how neurons migrate from where they form, next to the fetal brain’s central cavities, out to their final resting place in the brain’s outer layers. © Copyright Reed Business Information Ltd.
By Esther Landhuis Peer inside the brain of someone with Alzheimer’s disease, and you’ll see some striking features: shriveled nerve cells and strange protein clumps. According to a leading theory, proteins called amyloid beta and tau build up in the brain and choke nerve cell communication, setting the disease in motion years before people suspect anything is wrong with their recall. Yet the Alzheimer’s brain has another curious aspect. Some of the clusters of toxic amyloid proteins are entangled with octopus-like immune cells called microglia, cells that live in the brain to clear unwanted clutter. By munching on amyloid plaques, microglia are thought to help keep the disease at bay. But these housekeeping cells have an additional role—they switch on inflammatory pathways. Inflammation is critically important when the immune system encounters infection or needs to repair tissue. If left unchecked, however, the inflammatory process churns out toxic substances that can kill surrounding cells, whose death triggers more inflammation and creates a vicious cycle. For years scientists have probed how neuroinflammation contributes to Alzheimer’s disease and other neurodegenerative ailments. Researchers face a number of immediate questions: Is neuroinflammation a driving force? Does it kick in when the disease is already underway and worsen the process? Could it be harnessed for good in the early stages? Those questions are far from settled, but research is starting to reveal a clearer picture. “It may not be the amyloid plaques themselves that directly damage neurons and the connections between them. Rather, it may be the immune reaction to the plaques that does the damage,” says Cynthia Lemere, a neuroscientist at Brigham and Women’s Hospital. Still, it is hard to say if microglia are good guys or bad, making it challenging to create therapeutics that target these cells. © 2016 Scientific American
Nicola Davis The proportion of older people suffering from dementia has fallen by a fifth over the past two decades with the most likely explanation being because men are smoking less and living healthier lives, according to new scientific research. A team from three British universities concluded that as a result the number of new cases of dementia is lower than had been predicted in the 1990s, estimated at around 210,000 a year in the UK as opposed to 250,000. The findings are potentially significant because they suggest that it is possible to take preventative action, such as stopping smoking and reducing cholesterol, that could help avoid the condition. “Physical health and brain health are clearly highly linked,” said Carol Brayne of Cambridge University, who co-authored the study. Nick Fox, professor of neurology at University College, London, who was not involved in the study, agrees: “This does suggest that our risk, in any particular age in later life, can be reduced probably by what we do 10, 20 or 30 years before.” The scientists found that new cases of dementia had dropped from 20.1 in every 1,000 people per year in the first study conducted in the early 1990s to 17.7 in the second, which looked at new cases between 2008 and 2013. When sex and age differences were taken into account, the dementia rates were found to have dropped by 20%. The trend emerges from a dramatic drop in new cases for men across all age groups. In the 1990s study, for every 1,000 men aged 70-74, 12.9 went on to develop dementia within a year. In the second study, 20 years later, that figure had dropped to only 8.7 men. For men aged 65-69 the rate of new cases had more than halved between the two studies. © 2016 Guardian News and Media Limited
Link ID: 22122 - Posted: 04.20.2016
Ian Sample Science editor The subtle impact of genetics on the age at which people lose their virginity has been teased apart by scientists and shown to have an effect on how well people fare at school. Though mostly driven by upbringing and peer behaviour, a person’s age when they first have sex is also shaped by biological factors where genes have a role to play. Researchers found that differences in DNA could account for a quarter of the variation in the age at which people lost their virginity, with other factors, among them religious beliefs, family background and peer pressure, making up the rest. Genes influence academic ability across all subjects, latest study shows Read more “We were able to calculate for the first time that there is a heritable component to age at first sex, and the heritability is about 25%, so one quarter nature, three quarters nurture,” said John Perry, an expert in reproductive ageing and related health conditions at Cambridge University. Among 38 sections of DNA found to affect the age at which people first had sex were genes that drive reproductive biology, such as the release of sex hormones and the age of puberty. Still others were found that appear to affect behaviour, personality and appearance. A variant of one of the genes, named CADM2, linked an early start to one’s sex life with risk-taking behaviour and having a large number of children. A version of another gene, MSRA, found in people who lost their virginity later than average, was linked to irritability. © 2016 Guardian News and Media Limited
Scientists believe injections of a natural protein may lessen the symptoms and progress of Alzheimer's dementia after promising early trials in mice. The treatment - IL 33 - appeared to improve memory and help clear and prevent brain deposits similar to those seen in people with Alzheimer's. Tentative human studies of the treatment will soon begin, but experts say it will take many years to know if it could help patients in real life. The work is published in PNAS journal. Interleukin 33, or IL 33 for short, is made by the body as part of its immune defence against infection and disease, particularly within the brain and spinal cord. And patients with Alzheimer's have been found to have lower amounts of IL 33 in their brains than healthy adults. The researchers from the University of Glasgow and the Hong Kong University of Science and Technology tested what effect a boost of IL 33 might have on mice bred to have brain changes akin to Alzheimer's. The rodents rapidly improved their memory and cognitive function to that of the age-matched normal mice within a week of having the injections. Prof Eddy Liew, who led the work at the University of Glasgow, is excited but cautious about his findings. "Exciting as it is, there is some distance between laboratory findings and clinical applications. There have been enough false 'breakthroughs' in the medical field to caution us not to hold our breath until rigorous clinical trials have been done." © 2016 BBC.
Link ID: 22115 - Posted: 04.19.2016
For the first time, scientists have scanned the brains of subjects taking LSD, and found that the LSD state mimics that of infants. NPR's Rachel Martin speaks with researcher Robin Carhart-Harris. RACHEL MARTIN, HOST: Picture yourself in a boat on a river with tangerine trees and marmalade skies. Now picture yourself as a baby. You gaze up at your mother. She's got those kaleidoscope eyes. Pretty trippy, right? Turns out in a new study of brain scans, that the minds of people on LSD function in a similar way to babies' brains. Dr. Robin Carhart-Harris from Imperial College London's Center for Neuropsychopharmacology joins us from the studios of the BBC to talk about this study. So I understand this was the first time that brain scans like this have ever been done, looking specifically at the brains of people who have used LSD. How much LSD had your subjects taken? I mean, what were the prerequisites for a brain that you were going to scan? CARHART-HARRIS: Yeah, so they had to have had at least one experience with a psychedelic drug. So that includes LSD. It also includes magic mushrooms, other concoctions like ayahuasca, which is an Amazonian brew that has psychedelic properties. We gave them a moderate dose of LSD, roughly equivalent to what you might call a hit of LSD or one blotter of LSD if it was to be taken recreationally. MARTIN: So what kind of vetting did you have to do of the participants in your study because we should say different people respond to LSD in different ways? There are risks associated with this drug. CARHART-HARRIS: That's quite right. All drugs have risks, and LSD's no exception. One of the risks is that you might recruit someone who has a psychological vulnerability. So we're very, very careful when we recruit our volunteers to ensure that they have a solid mental health background. They don't have any personal or family history of any psychotic disorders - so those are things like schizophrenia. We have a psychiatrist assess them. We also evaluate their health. So they are very thoroughly screened. © 2016 npr
Eleanor Ainge Roy in Dunedin An octopus has made a brazen escape from the national aquarium in New Zealand by breaking out of its tank, slithering down a 50-metre drainpipe and disappearing into the sea. In scenes reminiscent of Finding Nemo, Inky – a common New Zealand octopus – made his dash for freedom after the lid of his tank was accidentally left slightly ajar. Staff believe that in the middle of the night, while the aquarium was deserted, Inky clambered to the top of his cage, down the side of the tank and travelled across the floor of the aquarium. Rob Yarrell, national manager of the National Aquarium of New Zealand in Napier, said: “Octopuses are famous escape artists. “But Inky really tested the waters here. I don’t think he was unhappy with us, or lonely, as octopus are solitary creatures. But he is such a curious boy. He would want to know what’s happening on the outside. That’s just his personality.” One theory is that Inky slid across the aquarium floor – a journey of three or four metres – and then, sensing freedom was at hand, into a drainpipe that lead directly to the sea. The drainpipe was 50 metres long, and opened on to the waters of Hawke’s Bay, on the east coast of New Zealand’s North Island. Another possible escape route could have involved Inky squeezing into an open pipe at the top of his tank, which led under the floor to the drain. © 2016 Guardian News and Media Limited
By Gareth Cook What are the most intelligent creatures on the planet? Humans come first. (Though there are days when we have to wonder.) After Homo sapiens, most people might answer chimpanzees, and then maybe dogs and dolphins. But what of birds? The science writer Jennifer Ackerman offers a lyrical testimony to the wonders of avian intelligence in her new book, “The Genius of Birds.” There have long been hints of bird smarts, but it’s become an active field of scientific inquiry, and Ackerman serves as tour guide. She answered questions from Mind Matters editor Gareth Cook. What drew you to birds? I’ve watched birds for most of my life. I admire all the usual things about them. Their plumage and song. Their intense way of living. Their flight. I also admire their resourcefulness and pluck. I’ve always been intrigued by their apparently smart behavior, whether learned or innate. I grew up in Washington, D.C. — the second youngest in a gaggle of five girls. My parents had precious little time for one-on-one. Especially my dad, who had a demanding government job. So when he asked me if I wanted to go birdwatching with him one spring morning when I was seven or eight, I jumped at the chance. It was magical, going out in the dark woods along the C&O canal and listening for bird song. My father had learned his calls and songs in Boy Scout camp from an expert, an elderly Greek man named Apollo, so he was pretty good at identifying birds, even the shy woodland species. Eventually he gave me my own copy of Peterson’s Field Guide, along with a small pair of binoculars. I’ve loved birds ever since. My first run in with a clever bird was on our dining room table. We had a pet parakeet, a budgerigar named Gre-Gre, who was allowed to fly around the dining room and perch on our head or shoulders. He had a kind of social genius. He made you love him. But at breakfast, it was impossible to eat your cereal without his constant harassment. He liked to perch on the edge of my bowl and peck at the cereal, flapping his wings frantically to keep his balance, splashing my milk. I’d build a barricade of boxes around my place setting, but he always found a way in, moving a box or popping over the top. He was a good problem-solver. © 2016 Scientific American
Dr. Perri Klass First of all, nobody takes a small child on an airplane for the fun of it. I have been there and I know. Don’t get me wrong, I’m no airplane saint; you won’t generally catch me offering to hold someone else’s kid, or making friends around the seatback. I don’t usually admit to being a pediatrician, for fear of hearing a medical saga. But I have put in my time on airplanes with my own infants and toddlers and small children, and I certainly know how it feels. Probably the best thing that can be said for traveling with young children is that it teaches you to appreciate traveling without them, however puzzling the inflight announcements, however long the delays, however tightly spaced the seats. I did enough economy-class traveling with children while my own were young that my reflexive reaction to all flight cancellations, turbulence or the moment when the person in front of me reclines the seat very suddenly, knocking my laptop closed, is now: At least I don’t have a small child with me – thank heavens. Babies do not cry on airplanes for the fun of it either. Nor do they cry, by and large, to let you know that their parents are neglectful or callous. They cry for infant versions of the same reasons that adults snap at one another about reclining seats, or elbow each other with quiet savagery over the armrest. They cry because their ears hurt and they’re being made to stay in a certain position when they don’t want to or the air smells strange and the noises are loud, or their stomachs feel upset or the day has been too long and they still aren’t there yet or they’re just plain cranky. As are we all. Crying is an evolutionary strategy to summon adult aid; over millennia, crying has probably evolved to be hard to ignore. I don’t know if it’s any comfort, but when you’re the parent with the crying baby, it doesn’t particularly help to be an expert. “I remember one flight where my daughter screamed the whole way and kept trying to get out of her seatbelt,” said my old friend, Dr. Elizabeth Barnett, a professor of pediatrics at Boston University and a travel medicine specialist. “As a parent, you feel two things — you’re in distress because you’re trying to comfort your child and not succeeding, so you feel bad for your child, and you also feel guilty because you know your child is disturbing everybody else.” © 2016 The New York Times Company
Sam Doernberg and Joe DiPietro It’s the first day of class, and we—a couple of instructors from Cornell—sit around a table with a few of our students as the rest trickle in. Anderson, one of the students seated across from us, smiles and says, “I’m going to get an A+ in your class.” “No,” VanAntwerp retorts, “I’m getting the A+.” You might think that this scene is typical of classes at a school like Cornell University, where driven students compete for top marks. But this didn’t happen on a college campus: It took place in a maximum-security prison. To the outside world, they are inmates, but in the classroom, they are students enrolled in the Cornell Prison Education Program, or “CPEP.” Per New York State Department of Corrections rules, we have permission to use the inmates’ last names only—which is also often how we know them best. Those who graduate from the program—taught by Cornell instructors—will receive an associate’s degree from Cayuga Community College. Before teaching neuroscience to prison inmates, we taught it to Cornell undergraduates as part of the teaching staff for Cornell’s Introduction to Neuroscience course. Most Cornell neuroscience students are high-achieving biology majors and premeds, who are well prepared to succeed in a demanding course. They generally have gone from one academic success to another, and it is no secret that they expect a similar level of success in a neuroscience class. © 2016 by The Atlantic Monthly Group
Keyword: Learning & Memory
Link ID: 22093 - Posted: 04.12.2016
By Jordana Cepelewicz The brain relies on a system of chemical messengers, known as neurotransmitters, to carry missives from cell to cell. When all is well, these communications enable the brain to coordinate various functions, from complex thought to quick, knee-jerk reactions—but when the system is out of whack, serious disease or disorder can ensue. A team of researchers at the Technical University of Denmark (D.T.U.) and University of Oxford have for the first time identified the molecular structure of dopamine beta-hydroxylase (DBH), the enzyme that controls the conversion between dopamine and norepinephrine, two major neurotransmitters. Understanding the crystal structure of the enzyme could provide an ideal target for drug development. Dopamine and norepinephrine play key roles in many brain functions such as learning, memory, movement and the fight-or-flight response. Imbalances in the levels of these neurotransmitters—and the role DBH plays in regulating them—have been implicated in a wide range of disorders, including hypertension, congestive heart failure, anxiety, depression, post-traumatic stress disorder, Alzheimer’s, schizophrenia, Parkinson’s and even cocaine addiction. DBH has long intrigued biochemists but it has been challenging to perform the analyses needed to determine the protein’s structure. “This enzyme has been particularly difficult,” says Hans Christensen, a chemist at D.T.U. and the study’s lead researcher. “We tried many different expression systems before we finally succeeded. Now that we have the structure it is clear why—[it] is very intricate, with different parts of the enzyme interacting very tightly.” © 2016 Scientific American,
By Melinda Wenner Moyer What if you could pop a pill that made you smarter? It sounds like a Hollywood movie plot, but a new systematic review suggests that the decades-long search for a safe and effective “smart drug” (see below) might have notched its first success. Researchers have found that modafinil boosts higher-order cognitive function without causing serious side effects. Modafinil, which has been prescribed in the U.S. since 1998 to treat sleep-related conditions such as narcolepsy and sleep apnea, heightens alertness much as caffeine does. A number of studies have suggested that it could provide other cognitive benefits, but results were uneven. To clear up the confusion, researchers then at the University of Oxford analyzed 24 studies published between 1990 and 2014 that specifically looked at how modafinil affects cognition. In their review, which was published last year in European Neuropsychopharmacology, they found that the methods used to evaluate modafinil strongly affected the outcomes. Research that looked at the drug's effects on the performance of simple tasks—such as pressing a particular button after seeing a certain color—did not detect many benefits. Yet studies that asked participants to do complex and difficult tasks after taking modafinil or a placebo found that those who took the drug were more accurate, which suggests that it may affect “higher cognitive functions—mainly executive functions but also attention and learning,” explains study co-author Ruairidh Battleday, now a medical doctor and Ph.D. student at the University of California, Berkeley. But don't run to the pharmacy just yet. Although many doctors very likely prescribe the drug off-label to help people concentrate—indeed, a 2008 survey by the journal Nature found that one in five of its readers had taken brain-boosting drugs, and half those people had used modafinil—trials have not yet been done on modafinil's long-term effectiveness or safety. © 2016 Scientific American
Laura Sanders NEW YORK — Cells in a brain structure known as the hippocampus are known to be cartographers, drawing mental maps of physical space. But new studies show that this seahorse-shaped hook of neural tissue can also keep track of social space, auditory space and even time, deftly mapping these various types of information into their proper places. Neuroscientist Rita Tavares described details of one of these new maps April 2 at the annual meeting of the Cognitive Neuroscience Society. Brain scans had previously revealed that activity in the hippocampus was linked to movement through social space. In an experiment reported last year in Neuron, people went on a virtual quest to find a house and job by interacting with a cast of characters. Through these social interactions, the participants formed opinions about how much power each character held, and how kindly they felt toward him or her. These judgments put each character in a position on a “social space” map. Activity in the hippocampus was related to this social mapmaking, Tavares and colleagues found. It turns out that this social map depends on the traits of the person who is drawing it, says Tavares, of Icahn School of Medicine at Mount Sinai in New York City. People with more social anxiety tended to give more power to characters they interacted with. What’s more, these people's social space maps were smaller overall, suggesting that they explored social space less, Tavares says. Tying these behavioral traits to the hippocampus may lead to a greater understanding of social behavior — and how this social mapping may go awry in psychiatric conditions, Tavares said. © Society for Science & the Public 2000 - 2016.
Keyword: Learning & Memory
Link ID: 22076 - Posted: 04.06.2016
by Daniel Galef Footage from a revolutionary behavioural experiment showed non-primates making and using tools just like humans. In the video, a crow is trying to get food out of a narrow vessel, but its beak is too short for it to reach through the container. Nearby, the researchers placed a straight wire, which the crow bent against a nearby surface into a hook. Then, holding the hook in its beak, it fished the food from the bottle. Corvids—the family of birds that includes crows, ravens, rooks, jackdaws, and jays—are pretty smart overall. Although not to the level of parrots and cockatoos, ravens can also mimic human speech. They also have a highly developed system of communication and are believed to be among the most intelligent non-primate animals in existence. McGill Professor Andrew Reisner recalls meeting a graduate student studying corvid intelligence at Oxford University when these results were first published in 2015. “I had read early in the year that some crows had been observed making tools, and I mentioned this to him,” Reisner explained. “He said that he knew about that, as it had been he who had first observed it happening. Evidently the graduate students took turns watching the ‘bird box,’ […] and the tool making first occurred there on his shift.”
By Roni Caryn Rabin Alzheimer’s disease is a progressive brain disorder that causes dementia, destroying memory, cognitive skills, the ability to care for oneself, speak and walk, said Ruth Drew, director of family and information services at the Alzheimer’s Association. “And since the brain affects everything, Alzheimer’s ultimately affects everything,” she said, “including the ability to swallow, cough and breathe.” Once patients reach the advanced stages of Alzheimer’s, they may stop eating and become weak and susceptible to infections, said Dr. Jason Karlawish, a professor of medicine at the University of Pennsylvania. Unable to swallow or cough, they are at high risk of choking, aspirating food particles or water into the lungs and developing pneumonia, which is often the immediate cause of death, he said. “You see a general decline in the contribution the brain makes, not just in thinking, but in maintaining the body’s homeostasis,” Dr. Karlawish said. Using a feeding tube to nourish patients and hospitalizing them for infections does not significantly extend life at the advanced stages of the disease and is discouraged because it can prolong suffering with no hope of recovery, he said. Alzheimer's is the sixth leading cause of death in the United States, according to the Centers for Disease Control and Prevention, but that figure may underestimate the actual number of cases, Dr. Karlawish said, since some deaths may be attributed to other causes like pneumonia. © 2016 The New York Times Company
Link ID: 22071 - Posted: 04.06.2016
Laura Sanders NEW YORK — Sometimes forgetting can be harder than remembering. When people forced themselves to forget a recently seen image, select brain activity was higher than when they tried to remember that image. Forgetting is often a passive process, one in which the memory slips out of the brain, Tracy Wang of the University of Texas at Austin said April 2 at the annual meeting of the Cognitive Neuroscience Society. But in some cases, forgetting can be deliberate. Twenty adults saw images of faces, scenes and objects while an fMRI scanner recorded their brains’ reactions to the images. If instructed to forget the preceding image, people were less likely to remember that image later. Researchers used the scan data to build a computer model that could infer how strongly the brain responds to each particular kind of image. In the ventral temporal cortex, a part of the brain above the ear, brain patterns elicited by a particular image were stronger when a participant was told to forget the sight than when instructed to remember it. Of course, everyone knows that it’s easy to forget something without even trying. But these results show that intentional forgetting isn’t a passive process — the brain has to actively work to wipe out a memory on purpose. Citations T.H. Wang et al. Forgetting is more work than remembering. Annual meeting of the Cognitive Neuroscience Society, New York City, April 2, 2016. © Society for Science & the Public 2000 - 2016
Keyword: Learning & Memory
Link ID: 22068 - Posted: 04.05.2016