Chapter 13. Memory, Learning, and Development
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By CLAUDIA DREIFUS MONTREAL — In many ways, the Obama administration’s new plan to map the human brain has its origins in the work of Brenda Milner, the neuropsychologist whose detailed observations of an amnesia patient in the 1950s showed how memory is rooted in specific regions of the brain. “Prior to Brenda Milner’s discoveries, many behaviorists and some cognitive psychologists followed the lead of Freud and Skinner in abandoning biology as a useful guide to the study of memory,” the Nobel laureate Dr. Eric Kandel wrote in his memoir, “In Search of Memory.” “Milner’s work changed all that.” The amnesia patient, Henry Molaison (known during his lifetime only as H.M., to protect his privacy), died at 82 in 2008; his brain is now being dissected and digitally mapped in exquisite detail. But Dr. Milner is still very much alive. Two months short of her 95th birthday, she puts in full days at the Montreal Neurological Institute and Hospital, where she is studying left/right brain differences. We spoke in her offices here at “the Neuro” and at the annual meeting of the American Association for the Advancement of Science in Boston. Here is a condensed and edited version of the conversations. How did you come to work with H.M., perhaps the most famous patient in the history of neuroscience? In 1950, while working on a doctorate at McGill, I went to work here at the Montreal Neurological Institute to study the patients of Dr. Wilder Penfield. He’d created the Neuro as a place to pioneer the neurosurgical treatment of epilepsy. He’d developed a procedure for patients who were having epileptic seizures because of brain injuries where he’d excise the injured part of the brain. © 2013 The New York Times Company
Keyword: Learning & Memory
Link ID: 18181 - Posted: 05.21.2013
by Andy Coghlan An experimental stem-cell treatment has restored the sight of a man blinded by the degeneration of his retinal cells. The man, who is taking part in a trial examining the safety of using human embryonic stem cells (hESCs) to reverse two common causes of blindness, can now see well enough to be allowed to drive. People undergoing treatment had reported modest improvements in vision earlier in the trial, which began in 2011, but this individual has made especially dramatic progress. The vision in his affected eye went from 20/400 – essentially blind – to 20/40, which is considered sighted. "There's a guy walking around who was blind, but now can see," says Gary Rabin, chief executive officer of Advanced Cell Technology, the company in Marlborough, Massachusetts that devised the treatment. "With that sort of vision, you can have a driver's licence." In all, the company has so far treated 22 patients who either have dry age-related macular degeneration, a common condition that leaves people with a black hole in the centre of their vision, or Stargardt's macular dystrophy, an inherited disease that leads to premature blindness. The company wouldn't tell New Scientist which of the two diseases the participant with the dramatic improvement has. In both diseases, people gradually lose retinal pigment epithelial (RPE) cells. These are essential for vision as they recycle protein and lipid debris that accumulates on the retina, and supply nutrients and energy to photoreceptors – the cells that capture light and transmit signals to the brain. © Copyright Reed Business Information Ltd.
by Caroline Williams Those at risk of developing Alzheimer's may be able to slow its onset through daily B vitamins. We already know that a high level of the amino acid homocysteine in the blood is a risk factor for Alzheimer's, and that B vitamin supplements help reduce homocysteine levels. But it was unclear whether or not these supplements would slow the progression of mild cognitive impairment (MCI) to Alzheimer's. David Smith and Gwenaëlle Douaud at the University of Oxford led a research effort to find out. They used MRI to track changes in the brains of 200 elderly volunteers with MCI over two years. During this time, half were given high doses of vitamin B12, B6 and folic acid – 300, 20 and 4 times the UK guideline daily amounts, respectively. The rest took a placebo. In 2010, Smith and his colleagues showed that high doses of B vitamins slowed whole-brain shrinkage by up to 53 per cent in patients with above average homocysteine levels. Now Smith and Douaud's team have looked deeper to work out which brain regions are best protected. They found that it was the areas of the brain most seriously affected by Alzheimer's, including the hippocampus and cerebellum, that were protected in volunteers given the vitamins. For instance, in those with high homocysteine, the atrophy rate in these brain regions was 5.2 per cent in the placebo group but just 0.6 per cent in the vitamin group. © Copyright Reed Business Information Ltd.
By Maggie Fox, Senior Writer, NBC News It might seem against all logic, but adding a little olive oil or a handful of nuts to your diet each day may help keep your mind clear, researchers reported on Monday. It’s the same diet that’s also been shown to reduce deaths from heart attacks and strokes. The researchers found that people who ate these healthy fats were less likely to show the early signs of dementia than those who stuck to a more traditional diet. And this was done in Spain -- where people are already eating a so-called Mediterranean diet. “Our ﬁndings support increasing evidence on the protective effects of the Mediterranean Diet on cognitive function,” Miguel Martinez-Gonzalez of the University of Navarra in Spain and colleagues reported in the Journal of Neurology, Neurosurgery and Psychiatry. The findings come from a large and well-publicized trial that showed the Mediterranean diet rich in fruits, vegetables, olive oil and a little wine can cut the risk of heart attacks and strokes by 30 percent. Martinez and colleagues took a part data on 500 volunteers from their own study center, who were followed for more than six and a half years after starting the diet. A Mediterranean diet includes lots of salad, fruit, vegetables, nuts, a little fish, a little lean meat, a small amount of cheese and olive oil. Wine is also served at meals. In the main study, 7,400 volunteers got extra counseling, and either a weekly supply of extra-virgin olive oil or mixed nuts -- walnuts, almonds and hazelnuts. © 2013 NBCNews.com
Link ID: 18176 - Posted: 05.21.2013
by Emily Underwood If you are one of the 20% of healthy adults who struggle with basic arithmetic, simple tasks like splitting the dinner bill can be excruciating. Now, a new study suggests that a gentle, painless electrical current applied to the brain can boost math performance for up to 6 months. Researchers don't fully understand how it works, however, and there could be side effects. The idea of using electrical current to alter brain activity is nothing new—electroshock therapy, which induces seizures for therapeutic effect, is probably the best known and most dramatic example. In recent years, however, a slew of studies has shown that much milder electrical stimulation applied to targeted regions of the brain can dramatically accelerate learning in a wide range of tasks, from marksmanship to speech rehabilitation after stroke. In 2010, cognitive neuroscientist Roi Cohen Kadosh of the University of Oxford in the United Kingdom showed that, when combined with training, electrical brain stimulation can make people better at very basic numerical tasks, such as judging which of two quantities is larger. However, it wasn't clear how those basic numerical skills would translate to real-world math ability. © 2010 American Association for the Advancement of Science
Keyword: Learning & Memory
Link ID: 18168 - Posted: 05.18.2013
by Douglas Heaven Got a memory like a fish? The first study to visualise live memory retrieval in the whole brain has not only debunked the "three-second memory" myth, but also sheds light on the brain processes involved in forming long-term memories. Even the haziest recollections have a physical basis in the brain, but the mechanisms behind the formation and retrieval of memories are not well understood. By working with zebrafish, which are small and partially transparent, Hitoshi Okamoto at the RIKEN Brain Science Institute in Wako, Japan, and colleagues were able to study the whole brain at once. This allowed them to observe the roles played by different brain regions as a memory was retrieved. The team used fish with a genetically engineered fluorescent protein in the brain that glows less brightly when calcium levels increase – which occurs when neurons fire. They were able to study the activity of these proteins under a microscope. First, the team trained a group of fish to respond to a visual cue to avoid a small electric shock. Each fish was placed in a tank containing two compartments. When a red light shone in one compartment the fish had to swim to the other to avoid the shock. The researchers then selected the fish that had learned to perform the avoidance task successfully at least 80 per cent of the time and looked at the activity in their brains while a red light was switched on and off. © Copyright Reed Business Information Ltd.
Keyword: Learning & Memory
Link ID: 18167 - Posted: 05.18.2013
By Tina Hesman Saey COLD SPRING HARBOR, N.Y. – Taming foxes changes not only the animals’ behavior but also their brain chemistry, a new study shows. The finding could shed light on how the foxes’ genetic cousins, wolves, morphed into man’s best friend. Lenore Pipes of Cornell University presented the results May 10 at the Biology of Genomes conference. The foxes she worked with come from a long line started in 1959 when a Russian scientist named Dmitry Belyaev attempted to recreate dog domestication, but using foxes instead of wolves. He bred silver foxes (Vulpes vulpes), which are actually a type of red fox with white-tipped black fur. Belyaev and his colleagues selected the least aggressive animals they could find at local fox farms and bred them. Each generation, the scientists picked the tamest animals to mate, creating ever friendlier foxes. Now, more than 50 years later, the foxes act like dogs, wagging their tails, jumping with excitement and leaping into the arms of caregivers for caresses. At the same time, the scientists also bred the most aggressive foxes on the farms. The descendents of those foxes crouch, flatten their ears, growl, bare their teeth and lunge at people who approach their cages. The foxes’ tame and aggressive behaviors are rooted in genetics, but scientists have not found DNA changes that account for the differences. Rather than search for changes in genes themselves, Pipes and her colleagues took an indirect approach, looking for differences in the activity of genes in the foxes’ brains. © Society for Science & the Public 2000 - 2013
Keyword: Genes & Behavior
Link ID: 18164 - Posted: 05.16.2013
By David Brown, A team of researchers said Wednesday that it had produced embryonic stem cells — a possible source of disease-fighting spare parts — from a cloned human embryo. Scientists at the Oregon Health and Science University accomplished in humans what has been done over the past 15 years in sheep, mice, cattle and several other species. The achievement is likely to, at least temporarily, reawaken worries about “reproductive cloning” — the production of one-parent duplicate humans. But few experts think that production of stem cells through cloning is likely to be medically useful soon, or possibly ever. “An outstanding issue of whether it would work in humans has been resolved,” said Rudolf Jaenisch, a biologist at MIT’s Whitehead Institute in Cambridge, Mass., who added that he thinks the feat “has no clinical relevance.” “I think part of the significance is technical and part of the significance is historical,” said John Gearhart, head of the Institute for Regenerative Medicine at the University of Pennsylvania. “Many labs attempted it, and no one had ever been able to achieve it.” A far less controversial way to get stem cells is now available. It involves reprogramming mature cells (often ones taken from the skin) so that they return to what amounts to a second childhood from which they can grow into a new and different adulthood. Learning how to make and manipulate those “induced pluripotent stem” (IPS) cells is one of biology’s hottest fields. © 1996-2013 The Washington Post
By Jason G. Goldman There is a rich tradition in psychology and neuroscience of using animals as models for understanding humans. Humans, after all, are enormously complicated creatures to begin even from a strictly biological perspective. Tacking on the messiness that comes with culture makes the study of the human mind tricky, at best. So, just as biomedical scientists have relied upon the humble mouse, psychological and cognitive scientists have too turned to our evolutionary cousins in the animal kingdom as a means of better understanding ourselves. In her new book Animal Wise, journalist Virginia Morrell recounts a conversation with one researcher who pointed out that decades of research were built upon “rats, pigeons, and college sophomores, preferably male.” The college undergrads stood in for all of humanity, the rats served as representatives of all other mammals, and pigeons served as a model for the rest of the animal kingdom. The silly part isn’t that non-human animals can be used effectively as a means of understanding more about our own species. The idea is simple: understand how a simple system works, and you can make careful inferences about the way that complex systems work. That is (or should be) obvious. In his interview with CNN today, memory research pioneer and Nobel Prize winner Eric Kandel said as much: “Rather than studying the most complex form of memory in a very complicated animal, we had to take the most simple form — an implicit form of memory — in a very simple animal.” © 2013 Scientific American
Ed Yong The US adolescents who signed up for the Study of Mathematically Precocious Youth (SMPY) in the 1970s were the smartest of the smart, with mathematical and verbal-reasoning skills within the top 1% of the population. Now, researchers at BGI (formerly the Beijing Genomics Institute) in Shenzhen, China, the largest gene-sequencing facility in the world, are searching for the quirks of DNA that may contribute to such gifts. Plunging into an area that is littered with failures and riven with controversy, the researchers are scouring the genomes of 1,600 of these high-fliers in an ambitious project to find the first common genetic variants associated with human intelligence. The project, which was launched in August 2012 and is slated to begin data analysis in the next few months, has spawned wild accusations of eugenics plots, as well as more measured objections by social scientists who view such research as a distraction from pressing societal issues. Some geneticists, however, take issue with the study for a different reason. They say that it is highly unlikely to find anything of interest — because the sample size is too small and intelligence is too complex. Earlier large studies with the same goal have failed. But scientists from BGI’s Cognitive Genomics group hope that their super-smart sample will give them an edge, because it should be enriched with bits of DNA that confer effects on intelligence. “An exceptional person gets you an order of magnitude more statistical power than if you took random people from the population — I’d say we have a fighting chance,” says Stephen Hsu, a theoretical physicist from Michigan State University in East Lansing, who acts as a scientific adviser to BGI and is one of the project’s leaders. © 2013 Nature Publishing Group,
Pregnant mothers’ exposure to the flu was associated with a nearly fourfold increased risk that their child would develop bipolar disorder in adulthood, in a study funded by the National Institutes of Health. The findings add to mounting evidence of possible shared underlying causes and illness processes with schizophrenia, which some studies have also linked to prenatal exposure to influenza. “Prospective mothers should take common sense preventive measures, such as getting flu shots prior to and in the early stages of pregnancy and avoiding contact with people who are symptomatic,” said Alan Brown, M.D., M.P.H, of Columbia University and New York State Psychiatric Institute, a grantee of the NIH’s National Institute of Mental Health (NIMH). “In spite of public health recommendations, only a relatively small fraction of such women get immunized. The weight of evidence now suggests that benefits of the vaccine likely outweigh any possible risk to the mother or newborn.” Brown and colleagues reported their findings online May 8, 2013 in JAMA Psychiatry. Although there have been hints of a maternal influenza/bipolar disorder connection, the new study is the first to prospectively follow families in the same HMO, using physician-based diagnoses and structured standardized psychiatric measures. Access to unique Kaiser-Permanente, county and Child Health and Development Study External Web Site Policy databases made it possible to include more cases with detailed maternal flu exposure information than in previous studies.
By Scicurious Aging happens. As you get older, your body slows down, eventually your brain slows down, too. Some things go gradually, and some go suddenly. To many people, this might seem like a pretty random process. We used to think of aging this way, as just…well cells get old, which means we get old, too. DNA replication after a while starts making errors in repair, the errors build up, and on the whole body scale the whole thing just kind of goes downhill. It seems random. But in fact, it’s not. There are specific proteins which can help control this process. And one of these, NF-kB, in one particular brain region, may have a very important role indeed. NF-kB (which stands for nuclear factor kappa-light-chain-enhancer of activated B cells, which is why we use NF-kB) is a protein complex that has a lot of roles to play. It’s an important starting player in the immune system, where it helps to stimulate antibodies. It’s important in memory and stress responses. NF-kB is something called a transcription factor, which helps to control what DNA is transcribed to RNA, and therefore what proteins will eventually be produced. Transcription factors, as you can see, can have a very large number of functions. But in the hypothalamus, NF-kB may have the added function of helping to control aging. The hypothalamus is an area of many small nuclei (further sub areas of neurons) located at the base of the brain. It’s been coming more and more into vogue lately among neuroscientists. In the past, we were interested in the hypothalamus mostly for its role in controlling hormone release from the dangling pituitary gland before it, but now we are learning that the hypothalamus can play roles in fear, mood, food intake, reproduction, and now…aging. © 2013 Scientific American
By DAVID DOBBS In the autistic person, it seems, hums a vital and distinctive essence — but one whose nature is obscured by thick layers of behavior and perception. Or, as Temple Grandin puts it, “two panes of glass.” For a quarter century, Dr. Grandin — the brainy, straight-speaking, cowboy-shirt-wearing animal scientist and slaughterhouse designer who at 62 is perhaps the world’s most famous autistic person — has been helping people break through the barriers separating autistic from nonautistic experience. Like Dr. Sacks, who made her famous as the title figure in his 1995 collection “An Anthropologist on Mars,” Dr. Grandin has helped us understand autism not just as a phenomenon, but as a different but coherent mode of existence that otherwise confounds us. In her own books and public appearances, she excels at finding concrete examples that reveal the perceptual and social limitations of autistic and “neurotypical” people alike. In “The Autistic Brain,” her latest book, written with the science author Richard Panek, she shows this talent most vividly in a middle chapter that looks at the sensory world of autism. It is a world filled with anomalies, in which everyday sensations can be overwhelming: A school bell can feel like a dentist’s drill, a scratchy shirt like a swarm of fire ants. In other cases the autistic person may feel so little sensation that she’ll try to fill the vacuum and create some sort of order — hence the rocking, twirling, hand-flapping, noisemaking behaviors that can discomfit and alienate onlookers. © 2013 The New York Times Company
Link ID: 18149 - Posted: 05.14.2013
By Melanie Tannenbaum Imagine that you’re an infant monkey, and you’ve just been thrown into a cage after several hours in isolation. You’ve been deprived of food, so you’re starving. Facing you are two adult-looking (fake) monkeys, designed to look like each one could potentially be your mother. On the left is a “wire mother,” equipped with a bottle and feeding tube so you can cling to her and fill your belly with milk. On the right is a “cloth mother,” with no bottle, but with a fuzzy terrycloth exterior that will allow for hours of soft, warm snuggles. You can only run to one of the monkeys. Which one will you choose? Six or seven decades ago, many psychologists would have claimed that any affection that we experience towards our parental figures is a purely behaviorist response. After many instances of conditioning a sense of “positive affect” after receiving life-sustaining food from mothers, children associate that positive emotion with these caregivers, an association that serves as the sole explanation for why people “love” their mothers. But that’s not what Harry Harlow thought. Harlow, a psychologist working at the University of Wisconsin – Madison during the 1960s, believed that there was something more important underlying our affection for Mom and Dad than our primal need to eat and survive. He believed that there was an additional factor: Comfort. What Harlow did to test this hypothesis was arguably ingenious, though inarguably cruel.1 Harlow deprived monkeys of food, making them desperately hungry, and then stuck them into a cage where they had a choice of two “mother figures” to run towards. On the left was a wire mother – cold and uncomfortable, yet equipped with a bottle that would feed the baby with life-sustaining nutrients. On the right was a cloth mother – warm, soft, and comfortable, yet unable to provide the infant with any food. If the only reason why we “love” our mothers (and fathers) is based on a conditioned response to our need for food, then the infant monkeys should run to the wire mothers who can feed them every time. © 2013 Scientific American
By Puneet Kollipara Identical twin mice sharing the same mazelike environment develop distinct personalities based on how much they explore their surroundings, researchers report in the May 10 Science. After death, those differences were reflected in the animals’ brains. The study “highlights something for which we had some intuition before, but actually quantifies it,” says Fred Gage, a neuroscientist at the Salk Institute for Biological Studies in La Jolla, Calif. Some character and biological differences between identical twins may originate as early as pregnancy. But twins become more and more different as life goes on, even when they grow up together. Scientists have recognized that having distinct experiences within the same environment might boost such personality differences, but that’s difficult to test in humans. Studying it in animals has multiple benefits. “You can keep the genes constant and also keep the environment constant,” says Gerd Kempermann of the Center for Regenerative Therapies Dresden in Germany. “It’s much more controlled than in a human situation.” Researchers led by Kempermann put 40 genetically identical female mice in an elaborate cage and observed their behavior. The cage had multiple levels linked together by tubes and contained toys and other features that the animals could explore. The researchers equipped each mouse with a microchip that tracked its location, using the animals’ movements as a measure of exploratory behavior. Initially, the mice differed only slightly in their tendency to roam. As they grew older, all tended to explore more often, but the differences among the mice grew more pronounced. © Society for Science & the Public 2000 - 2013
By Ian Chant Most people make good decisions most of the time. But when drug addiction, disease or brain injury enters the picture, rational thinking can go awry. What if the damaged brain just needed a little reminder of how it feels to choose wisely? Enter the MIMO neural prosthesis, an array of electrodes implanted in the brain that make contact with eight neuron circuits in the prefrontal cor-tex, the brain's command center for decision making. The device can both record the brain activity associated with good choices and stimulate the relevant neurons to get the brain back on track. Although the implant can listen in only on a tiny subset of the neurons in this region, the scientists who developed it, based at Wake Forest Baptist Medical Center, were surprised to discover that they could still pick up signature patterns associated with correct choices, at least in the context of a simple task. The researchers tested the neural prosthesis on monkeys that were trained to move a cursor over a picture on a computer screen to get a food reward. The implant first recorded the brain activity associated with choosing the correct picture. Then the monkeys were given cocaine, and their performance plummeted. But when the implant was switched on to send electric current to the neurons that had earlier been associated with the correct answers, the monkeys immediately started selecting the right pictures again. Some of them did an even better job than they had before receiving cocaine. © 2013 Scientific American,
By Bruce Bower Provocative evidence that certain memory exercises make people smarter has sparked the rise of online brain-training programs such as Lumosity. But at least one type of brain training may not work as advertised, a new study finds. As expected, practicing improved volunteers’ performance on tests of memory and the ability to locate items quickly in busy scenes, say psychologist Thomas Redick of Indiana University Purdue University Columbus and his colleagues. That improvement did not, however, translate into higher scores on tests of intelligence and multitasking, the researchers report in the May Journal of Experimental Psychology: General. Redick’s investigation is part of a growing scientific debate about brain training, which is promoted by some companies as having a variety of mental benefits. Some researchers say that extensive instruction and training on memory tasks can indeed fortify reasoning and problem solving. Others are skeptical that vigorous memory sessions produce such wide-ranging effects. The dispute feeds into a longstanding scientific controversy about whether enriched environments can increase intelligence, as measured on IQ tests. What’s not up for debate is that many people feel smarter after brain training. In the new study, 10 of 23 individuals who completed memory sessions said that the program helped them to think, multitask and focus better in daily life. But the scientists say that even if some participants performed daily tasks better after memory training, they may simply have tried harder or felt better about their efforts due to a belief that training had strengthened their minds. © Society for Science & the Public 2000 - 2013
Keyword: Learning & Memory
Link ID: 18140 - Posted: 05.11.2013
By John McCarthy Into brains of newborn mice, researchers implanted human “progenitor cells.” These mature into a type of brain cell called astrocytes (see below). They grew into human astrocytes, crowding out mouse astrocytes. The mouse brains became chimeras of human and mouse, with the workhorse mouse brain cells – neurons – nurtured by billions of human astrocytes. Neuroscience is only beginning to discover what astrocytes do in brains. One job that is known is that they help neurons build connections (synapses) with other neurons. (Firing neurotransmitter molecules across synapses is how neurons communicate.) Human astrocytes are larger and more complex than those of other mammals. Humans’ unique brain capabilities may depend on this complexity. Human astrocytes certainly inspired the mice. Their neurons did indeed build stronger synapses. (Perhaps this was because human astrocytes signal three times faster than mouse astrocytes do.) Mouse learning sharpened, too. On the first try, for instance, altered mice perceived the connection between a noise and an electric shock (a standard learning test in mouse research). Normal mice need a few repetitions to get the idea. Memories of the doctored mice were better too: they remembered mazes, object locations, and the shock lessons longer. The reciprocal pulsing of billions of human and mouse brain cells inside a mouse skull is a little creepy. Imagine one of these hybrid mice exploring your living room. Would you feel like a Stone Age tribesman observing a toy robot? Does the thing think? © 2013 Scientific American
By James Gallagher Health and science reporter, BBC News Flu during pregnancy may increase the risk of the unborn child developing bipolar disorder later in life, research suggests. A study of 814 expectant women, published in JAMA Psychiatry, showed that infection made bipolar four times more likely. The overall risk remained low, but it echoes similar findings linking flu and schizophrenia. Experts said the risks were small and women should not worry. Bipolar leads to intense mood swings, which can last months, ranging from depression and despair to manic feelings of joy, overactivity and loss of inhibitions. Researchers at the Columbia University Medical Center identified a link between the condition, often diagnosed during late teens and twenties, and experiences in the womb. In their study looking at people born in the early 1960s, bipolar disorder was nearly four times as common in people whose mothers caught flu during pregnancy. The condition affects about one in 100 people. The lead researcher, Prof Alan Brown, estimated that influenza infection during pregnancy could lead to a 3-4% chance of bipolar disorder in the resulting children. However, in the vast majority of cases of bipolar disorder there would no history of flu. BBC © 2013
By MARILYNN MARCHIONE DEERFIELD, Ill. (AP) — Baxter International Inc. says that a blood product it was testing failed to slow mental decline or to preserve physical function in a major study of 390 patients with mild to moderate Alzheimer’s disease. The company says that people who received 18 months of infusions with its drug, Gammagard, fared no better than others given infusions of a dummy solution. Gammagard is immune globulin, natural antibodies culled from donated blood. Researchers thought these antibodies might help remove amyloid, the sticky plaque that clogs patients’ brains, sapping memory and ability to think. Patients with moderate disease and those with a gene that raises risk of Alzheimer’s who were taking the higher of two doses in the study seemed to benefit, although the study was not big enough to say for sure. ‘‘The study missed its primary endpoints, however we remain interested by the prespecified sub-group analyses’’ in groups that seemed to benefit, Ludwig Hantson, president of Baxter’s BioScience business, said in a statement. Gammagard is already sold to treat some blood disorders, and the results of the Alzheimer’s study do not affect those uses. About 35 million people worldwide have dementia, and Alzheimer’s is the most common type. In the U.S., about 5 million have Alzheimer's. Current medicines such as Aricept and Namenda just temporarily ease symptoms. There is no known cure. © 2013 NY Times Co.
Link ID: 18131 - Posted: 05.08.2013