By Michael Harré As humans, we aren't born with formidable armaments or defenses, nor are we the strongest, fastest, or biggest species, yet despite this we are amazingly successful. For a long time it was thought that this success was because our enlarged brains allows each of us to be smarter than our competitors: better at abstract thinking, better with tools and better at adapting our behavior to those of our prey and predators. But are these really the most significant skills our brains provide us with? Another possibility is that we are successful because we can form long-lasting relationships with many others in diverse and flexible ways, and that this, combined with our native intelligence, explains why homo sapiens came to dominate the planet. In every way from teaching our young to the industrial division of labour we are a massively co-operative species that relies on larger and more diverse networks of relationships than any other species. In 1992 British anthropologist Robin Dunbar published an article showing that, in primates, the ratio of the size of the neo-cortex to that of the rest of the brain consistently increases with increasing social group size. For example, the Tamarin monkey has a brain size ratio of about 2.3 and an average social group of size of about 5 members. On the other hand, a Macaque monkey has a brain size ratio of around 3.8 but a very large average group size of about 40 members. From this work Dunbar put forward what is now known as the “social brain hypothesis.” The relative size of the neo-cortex rose as social groups became larger in order to maintain the complex set of relationships necessary for stable co-existence. Most famously, Dunbar suggested that given the human brain ratio we have an expected social group size of around 150 people, about the size of what Dunbar called a “clan.” © 2012 Scientific American,

Keyword: Evolution
Link ID: 17141 - Posted: 08.08.2012

By Stephanie Pappas Senior Writer For women looking to pass on their genes, it pays to be short. For men, tall is the ideal. The result? An evolutionary tug-of-war in which neither gender reaches their perfect height. Those are the results of a new study published Aug. 7 in the journal Biology Letters. The research finds that an evolutionary battle of the sexes keeps the genders in an endless feedback loop of height variations across the generations. "We should not simply assume that when a trait is beneficial for one sex, that selection or evolution will necessarily favor this trait," study researcher Gert Stulp, a scientist at the University of Groningen in the Netherlands, told LiveScience in an email. In the same way, traits that harm one sex but not the other may not be "weeded out" by natural selection, Stulp said. "This may even hold for health-related traits, such that genetic underpinnings beneficial to the health of one sex may increase the susceptibility to disease in the other sex," he said. In modern western societies, studies have found that women who are on the short side tend to have more children. In contrast, average-height men do the best, reproductively speaking, outpacing short and tall men in number of children fathered, Stulp said. © 2012 NBCNews.com

Keyword: Sexual Behavior; Evolution
Link ID: 17140 - Posted: 08.08.2012

By Julie Appleby, An increasing number of psychiatrists and hospitals — as well as entrepreneurs opening rTMS centers around the country — are betting that there are millions of people like Curtis, discouraged by depression treatments that have proved unsuccessful and willing to pony up thousands of dollars for the possibility of relief. The treatment, which has been approved by the Food and Drug Administration, is covered by Medicare in five states, but few private insurers pay for it routinely. While rTMS has ardent supporters, its effectiveness is still debated, and there is little evidence showing how long the results last. The technique has been shown to work better than a placebo, but the proportion of patients who show complete relief ranges widely, from as few as 10 percent to as many as 57 percent, according to various studies. The debate has huge implications, not just for many of the 14 million Americans who suffer from major depression every year but also for businesses eyeing a potentially lucrative market and insurers weighing whether to cover it. About half of those 14 million Americans seek relief through psychotherapy and prescription drug treatment, according to an evaluation by the federal Agency for Healthcare Research and Quality. But studies show that antidepressants provide complete cessation of symptoms only about a third of the time. Magnetic stimulation is aimed at patients with such “treatment-resistant depression.” Supporters say rTMS is worth the cost — between $6,000 and $12,000 for the four-to-six-week treatment — because it enables people such as Curtis to resume productive lives. Skeptics question the price tag in light of uncertain benefits. © 1996-2012 The Washington Post

Keyword: Depression
Link ID: 17139 - Posted: 08.08.2012

By Scicurious Our brains are made of millions of neurons. Tons. A lot. We scientists spend a lot of time studying those neurons, how they function individually, and how they respond to outside stimulation. But neurons cannot function alone. What sets a neuron apart is its ability to carry electric signals and to transfer chemical signals to other neurons. The function of neurons is not in the neurons themselves, it is in the connection between them. And this incredibly complicated network, composed of billions of connections, is called the connectome. If we knew the connectome of the human, we’d know a lot more about the brain than we do now. We are learning it, little by little, but with a series of connections that are so incredibly vast, it’s just too much right now to examine every single possible connection. Right now the only way to ensure getting every single connection in painstaking detail is to use electron microscopy to view synapses, the connections between neurons. Concentrations of the little organelles which signify a synapse (such as vesicles full of neurotransmitter), can tell you where each connection is placed. But the electron microscope can only look at a very small section at a time, making the mapping of a connectome an incredibly arduous task. C. elegans, to be exact. The nematode is a darling of basic research, and for a very good reason. C. elegans is incredibly simple, having exactly 302 neurons in the entire body. Well, 302, or 383. There are two kinds of C. elegans, hermaphrodite and male (there are no females). The males mate with the hermaphrodites. But this means that the male C. elegans is slightly different from the hermaphrodite C. elegans. While the hermaphrodite has 302 neurons, the male has 383. And most of these appear to be devoted to a complex series of behaviors characteristic of mating. © 2012 Scientific American,

Keyword: Development of the Brain; Sexual Behavior
Link ID: 17138 - Posted: 08.07.2012

By Katherine Harmon Jill, a 60-year-old woman in Milwaukee, has overcome extreme poverty. So, now that she has enough money to put food in the fridge, she fills it. She also fills her freezer, her cupboard and every other corner of her home. “I use duct tape to close the freezer door sometimes when I’ve got too many things in there,” she told A&E’s Hoarders. Film footage of her kitchen shows a cat scrambling over a rotten grapefruit; her counters—and most surfaces in her home—seemed to be covered with several inches of clutter and spoiled food. “I was horrified,” her younger sister said after visiting Jill. And the landlord threatened eviction because the living conditions became unsafe. Jill joins many others who have been outed on reality TV as a “hoarder.” We might have once called people with these tendencies “collectors” or “eccentrics.” But in recent years, psychiatrists had suggested they have a specific type of obsessive-compulsive disorder (OCD). A movement is underfoot, however, for the new edition of the psychiatric field’s diagnostic bible (the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, or DSM-5), to move hoarding disorder to its own class of illness. And findings from a new brain scan study, published online August 6 in Archives of General Psychiatry, support this new categorization. Hoarding disorder is categorized as “the excessive acquisition of and inability to discard objects, resulting in debilitating clutter,” wrote the researchers behind the new study, led by Yale University School of Medicine’s David Tolin. © 2012 Scientific American,

Keyword: OCD - Obsessive Compulsive Disorder; Brain imaging
Link ID: 17137 - Posted: 08.07.2012

By KATIE THOMAS Johnson & Johnson and Pfizer announced on Monday that they were halting development of a closely watched Alzheimer’s drug after two clinical trials failed to show that it was effective in patients with mild to moderate forms of the disease. Late last month, results of a large clinical trial of the drug, called bapineuzumab, failed to show that patients — all of whom carried a particular gene that raises the risk of getting Alzheimer’s — improved either cognition or daily functioning compared with a placebo. The companies announced Monday that the results of a second trial, which tested the drug on patients who did not carry the gene, also did not meet its goals. Because the results of the earlier trial were already known, the decision to discontinue the drug was not altogether unexpected. Bapineuzumab, like other Alzheimer’s drugs being developed, targets beta amyloid, a protein that has toxic effects on the brain and is believed to be a cause of the disease. Given the failure of the drug, some have called that theory into question. But Dr. Husseini K. Manji, the global therapeutic area head for neuroscience at Janssen Research and Development, a unit of Johnson & Johnson, said the failed trials did not mean researchers should abandon the beta amyloid theory. “While we are disappointed in the results of the two bapineuzumab IV studies, particularly in light of the urgent need for new advancements in Alzheimer’s disease, we believe that targeting and clearing beta amyloid remains a promising path to potential clinical benefits for people suffering from this disease,” he said in a news release. © 2012 The New York Times Company

Keyword: Alzheimers
Link ID: 17136 - Posted: 08.07.2012

By Lara Salahi Can one head injury lead to Alzheimer’s? New research suggests one moderate to severe head injury can disrupt the proteins that regulate an enzyme associated with Alzheimer’s disease. Researchers from Tufts University School of Medicine and Harvard Medical School first measured protein levels in the brains of mice two days after they had incurred moderate to severe head trauma. The researchers found a reduction in the levels of two proteins, GGA1 and GGA3, and an increased level of the enzyme BACE1, which has previously been associated with Alzheimer’s disease. Researchers analyzed Alzheimer’s patients’ brain tissue and found the same protein reduction and enzyme level increase the mice had experienced. The findings suggest that a single brain injury could significantly increase the risk of developing Alzheimer’s disease, according to the researchers. BOTTOM LINE: A moderate to severe head injury can disrupt the proteins that regulate an enzyme associated with Alzheimer’s. CAUTIONS: The study does not look at the long-term effects of enzyme disruption after a traumatic brain injury and whether it leads to the development of Alzheimer’s disease. WHERE TO FIND IT: Journal of Neuroscience, July issue © 2012 NY Times Co.

Keyword: Alzheimers; Brain Injury/Concussion
Link ID: 17135 - Posted: 08.07.2012

by Michael Marshall The relatively sophisticated brain of a songbird has been transplanted into the body of a distantly related, less intelligent species. The study could help us understand how brains develop, perhaps opening the way to treating some brain conditions. Since 2009, Chun-Chun Chen of Duke University in Durham, North Carolina, has performed over 100 brain transplants in birds. In her latest study she transferred the cells destined to become the forebrain of zebra finches (Taeniopygia guttata) into Japanese quail (Coturnix japonica) embryos, after removing the equivalent quail cells. After the transplants, Chen incubated the eggs for up to 16 days, before opening them to find that the transplanted cells had integrated into their hosts, forming the normal neural pathways. None of the chimeric embryos hatched, however, perhaps because their hybrid brains could not trigger breathing. Chen says she will try to crack the hatching problem by transplanting just half a zebra finch forebrain, leaving half the quail forebrain still in place. Researchers have been attempting such transplants for decades. In 1957, Petar Martinovitch of Yale University transplanted the heads of one set of chicken embryos to another (Proceedings of the National Academy of Sciences, vol 43, p 354). Few survived. © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Evolution
Link ID: 17134 - Posted: 08.07.2012

By ANAHAD O'CONNOR THE FACTS Certain regions of the human brain are dedicated to the various senses. The visual cortex handles vision, for example, while the auditory cortex processes sound. But what happens if one of the senses is lost? Do the neurons in the auditory cortex of a deaf person atrophy and go to waste, for instance, or are they put to work processing vision and other senses? In studies, scientists have shown that when one sense is lost, the corresponding brain region can be recruited for other tasks. Researchers learned this primarily by studying the blind. Brain imaging studies have found that blind subjects can locate sounds using both the auditory cortex and the occipital lobe, the brain’s visual processing center. But recently a similar phenomenon was discovered in the deaf. In a study financed by the National Institutes of Health and published in The Journal of Neuroscience, researchers recruited 13 deaf volunteers and a dozen volunteers with normal hearing and looked at what happened in their brains when touch and vision responses were stimulated. They found that both senses were processed in Heschl’s gyrus, where the auditory cortex is situated, suggesting that this part of the brain had been dedicated to other senses. Other studies have shown that structural changes in the auditory cortex are noticeable in the brains of deaf children from a very early age. THE BOTTOM LINE Losing one sense can cause the brain to become rewired. Copyright 2012 The New York Times Company

Keyword: Pain & Touch; Hearing
Link ID: 17133 - Posted: 08.07.2012

By Alyssa A. Botelho, Melanie Brunson, who has been blind since birth, suddenly awoke and found herself standing at 15th and K streets in Northwest Washington. She had stopped at the corner on her way home from work to await a safe time to cross and had dozed off. Even on awakening, she was so groggy she couldn’t focus well enough to hear passing cars and judge when it was safe to cross. The incident was a startling reminder of the sleep problems that had plagued her since birth. “Who knows how long I had been standing there,” she said. “I realized then that my safety was in jeopardy, and I began searching for remedies with a vengeance.” But years after that 2005 traffic scare and many subsequent visits to doctors and sleep clinics, Brunson still lies awake in bed night after night and then is desperately sleepy during the day. Although doctors have not definitively identified her disorder, researchers believe she suffers from non-24-hour sleep-wake disorder, or “non-24.” The chronic and little-known sleep condition is characterized by a body clock that is not aligned with a 24-hour day. Though non-24 can affect those with normal vision, it is especially prevalent among blind people who cannot sense light, the strongest environmental signal that synchronizes the brain’s internal sleep-wake pattern to the 24-hour cycle of the Earth day. © 1996-2012 The Washington Post

Keyword: Biological Rhythms; Vision
Link ID: 17132 - Posted: 08.07.2012

by Anil Ananthaswamy Advocates of free will can rest easy, for now. A 30-year-old classic experiment that is often used to argue against free will might have been misinterpreted. In the early 1980s, Benjamin Libet, a neuroscientist at the University of California in San Francisco, used electroencephalography (EEG) to record the brain activity of volunteers who had been told to make a spontaneous movement. With the help of a precise timer that the volunteers were asked to read at the moment they became aware of the urge to act, Libet found there was a 200 millisecond delay, on average, between this urge and the movement itself. But the EEG recordings also revealed a signal that appeared in the brain even earlier, 550 milliseconds, on average, before the action. Called the readiness potential, this has been interpreted as a blow to free will, as it suggests that the brain prepares to act well before we are conscious of the urge to move. This conclusion assumes that the readiness potential is the signature of the brain planning and preparing to move. "Even people who have been critical of Libet's work, by and large, haven't challenged that assumption," says Aaron Schurger of the National Institute of Health and Medical Research in Saclay, France. One attempt to do so came in 2009. Judy Trevena and Jeff Miller of the University of Otago in Dunedin, New Zealand, asked volunteers to decide, after hearing a tone, whether or not to tap on a keyboard. The readiness potential was present regardless of their decision, suggesting that it did not represent the brain preparing to move. Exactly what it did mean, though, still wasn't clear. © Copyright Reed Business Information Ltd.

Keyword: Consciousness; Attention
Link ID: 17131 - Posted: 08.07.2012

By Laura Sanders When one monkey sees another monkey messing up, the event ignites a small cluster of nerve cells in the brain that are sensitively tuned to others’ failures. The results help explain why the members of another primate species are such exquisite connoisseurs of blame. “We humans are very sensitive to others’ mistakes,” says Masaki Isoda of the Okinawa Institute of Science and Technology in Japan. He and his colleagues describe the macaques’ blunder detectors online August 5 in Nature Neuroscience. Catching other people’s slipups isn’t just schadenfreude. Noting another’s lapse, be it a gymnast’s step out of bounds or another animal’s regurgitation of a poisonous berry, is a good way to learn about the world. “Everybody’s life is a bit of a trial-and-error game,” says neuroscientist Matthew Shane of the Mind Research Network in Albuquerque who was not involved in the new study. An ability to sense others’ errors helps to see what doesn’t work without suffering the consequences firsthand. Past studies have suggested that nerve cells in a brain region called the medial frontal cortex are general error catchers: The cells were thought to fire when a person makes a mistake and also when witnessing someone else err. But by listening in on single nerve cells in macaques, Isoda and his team found that some of these neurons don’t seem to care about a personal mistake. Instead, these neurons are exclusively trained on other animals’ errors. © Society for Science & the Public 2000 - 2012

Keyword: Attention
Link ID: 17130 - Posted: 08.07.2012

By Giulio Tononi When is an entity one entity? How can multiple elements be a single thing? A question simple enough— but one, thought Galileo, that had not yet been answered. Or perhaps, it had not been asked. The sensor of the digital camera certainly had a large repertoire of states— it could take any possible picture. But was it a single entity? You use the camera as a single entity, you grasp it with your hands as one. You watch the photograph as a single entity. But that is within your own consciousness. If it were not for you, the observer, would it still be a single entity? And what exactly would that mean? While musing such matters, Galileo was startled by a voice. J., a man with the forehead of an ancient god, addressed him in a polished tone: “Take a sentence of a dozen words, and take twelve men, and tell to each one word. Then stand the men in a row or jam them in a bunch, and let each think of his word as intently as he will; nowhere will there be a consciousness of the whole sentence. Or take a word of a dozen letters, and let each man think of his letter as intently as he will; nowhere will there be a consciousness of the whole word,” J. said. Or take a picture of one million dots, and take one million photodiodes, and show each photodiode its own dot. Then stand the photodiodes well ordered on a square array, and let each tell light from dark for its own dot, as precisely as it will; nowhere will there be a consciousness of the whole picture, said Galileo. “So you see that, Galileo,” J. continued. “There is no such thing as the spirit of the age, the sentiment of the people, or public opinion. The private minds do not agglomerate into a higher compound mind. They say the whole is more than the sum of its parts; they say, but how can it be so?” © 2012 Scientific American, Copyright © 2012 by Giulio Tononi

Keyword: Consciousness; Attention
Link ID: 17129 - Posted: 08.06.2012

By Susan E. Matthews The way people's pupils react when they see other people is an effective way to assess sexual orientation, according to a new study. The reactions of study participants' pupils revealed that heterosexual men responded most to images of women and homosexual men responded most to images of men. Additionally, researchers found that homosexual women responded most to images of women, and heterosexual women expressed arousal in response to both men and women, though they were more likely to choose to watch men. Previous studies have shown that people's pupils widen in response to seeing others who they find attractive; the new study showed that, indeed, a person's sexuality is evident in their pupils' responses. Results also revealed that bisexual men were attracted to both men and women, an idea that has been disputed, and that heterosexual women may be aroused by both genders, despite being straight. "The pupil reacts very quickly, and it is unconscious, so it's a method that gives us a subconscious indicator of sexuality," said lead study author Gerulf Rieger, a researcher at Cornell University. Sex researchers don't always want to rely on people's own reports about who they are sexually attracted to, because cultural and societal pressures can influence what people say, he explained. The findings are detailed today (Aug. 3) in the journal PLoS ONE. © 2012 NBCNews.com

Keyword: Sexual Behavior; Attention
Link ID: 17128 - Posted: 08.06.2012

by Will Ferguson Let's face it, child rearing isn't for everyone. Midnight diaper changes, a seriously compromised social life, and trading in the two-seater coupe for a mid-size sedan can be too much for some of us to handle. Readers who find themselves in this category might be reassured to know there's at least one other creature on the planet that is, in all likelihood, even more keen to shirk parental responsibility. The common cuckoo is notorious for pawning off its young on other birds, like the Eurasian Reed Warbler (Acrocephalus scirpaceus). Unfortunately for these more willing caregivers, the cuckoo is a ruthless parasite. Upon hatching, young cuckoos push their surrogate brothers and sisters from the nest, leaving the unsuspecting host with a single cuckoo chick rather than a brood of its own. For obvious reasons, reed warblers have never been happy with the arrangement. They will attack female cuckoos on sight, reducing the chance of their nest being targeted. However, the sly cuckoo has developed an innovative way to avoid hostilities. Female cuckoos have evolved two different guises to minimise the chance of being recognised and attacked by warblers. It's unusual for female birds of a single species to come in different colours, but the phenomenon is surprisingly common for female cuckoos. Some are brownish-red, while others have grey, hawk-like plumage that deters other birds from attacking them. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Evolution
Link ID: 17127 - Posted: 08.06.2012

Exercise and behavioural therapies are the most cost-effective and successful ways to treat Chronic fatigue syndrome, also known as ME, an analysis shows. A study of 640 patients showed these treatments had the potential to save the economy millions of pounds if they were widely adopted. The findings were published in the journal PLoS ONE. However, another treatment favoured by patients' groups was shown to offer little value. Nobody knows what causes the condition, yet a quarter of a million people in the UK are thought to have it. The symptoms include severe tiredness, poor concentration and memory as well as muscle and joint pain and disturbed sleep. An earlier version of this research, published last year, showed that cognitive behavioural therapy (changing how people think about their symptoms) and graded exercise therapy (gradually increasing the amount of exercise) were the most effective treatments. However, the study provoked anger from many patients' groups which argued that pacing therapies (learning to live within limits) were both better and safer for patients. Using data from the same set of patients, researchers compared improvements in levels of fatigue and activity with the cost to the NHS of providing the treatments. It concluded that only cognitive behavioural therapy and graded exercise therapy could be considered cost-effective. BBC © 2012

Keyword: Depression
Link ID: 17126 - Posted: 08.06.2012

by Nicholas St. Fleur With their trumpet-like calls, elephants may seem like some of the loudest animals on Earth. But we can't hear most of the sounds they make. The creatures produce low-frequency noises between 1 to 20 Hertz, known as infrasounds, that help them keep in touch over distances as large as 10 kilometers. A new study reveals for the first time how elephants produce these low notes. Scientists first discovered that elephants made infrasounds in the 1980s. The head female in a herd may produce the noises to guide her group's movements, whereas a male who’s in a mating state called musth might use the calls to thwart competition from other males. Mother elephants even rely on infrasounds to keep tabs on a separated calf, exchanging "I'm here" calls with the wayward offspring in a fashion similar to a game of Marco Polo. These noises, which fall below the hearing range for humans, are often accompanied by strong rumbles with slightly higher frequencies that people can hear. By recording the rumbles and then speeding up the playback, the scientists can increase the frequency of the infrasounds, making them audible. Good vibrations. The vocal folds of the excised larynx vibrating according to the myoelastic-aerodynamic method. Researchers have speculated that the noises come from vibrations in the vocal folds of the elephant larynx. This could happen in two ways. In the first, called active muscular contraction (AMC), neural signals cause the muscles in the larynx to contract in a constant rhythm. Cats do this when they purr. The second possibility is known as the myoelastic-aerodynamic (MEAD) method, and it occurs when air flows through the vocal folds causing them to vibrate—this also happens when humans talk. © 2010 American Association for the Advancement of Science

Keyword: Hearing; Evolution
Link ID: 17125 - Posted: 08.04.2012

Scientists have discovered a biological marker that may help to identify which depressed patients will respond to an experimental, rapid-acting antidepressant. The brain signal, detectable by noninvasive imaging, also holds clues to the agent’s underlying mechanism, which are vital for drug development, say National Institutes of Health researchers. The signal is among the latest of several such markers, including factors detectable in blood, genetic markers, and a sleep-specific brain wave, recently uncovered by the NIH team and grantee collaborators. They illuminate the workings of the agent, called ketamine, and may hold promise for more personalized treatment. "These clues help focus the search for the molecular targets of a future generation of medications that will lift depression within hours instead of weeks," explained Carlos Zarate, M.D., of the NIH’s National Institute of Mental Health (NIMH). "The more precisely we understand how this mechanism works, the more narrowly treatment can be targeted to achieve rapid antidepressant effects and avoid undesirable side effects." Previous research had shown that ketamine can lift symptoms of depression within hours in many patients. But side effects hamper its use as a first-line medication. So researchers are studying its mechanism of action in hopes of developing a safer agent that works similarly. Ketamine works through a different brain chemical system than conventional antidepressants. It initially blocks a protein on brain neurons, called the NMDA receptor, to which the chemical messenger glutamate binds.

Keyword: Depression; Brain imaging
Link ID: 17124 - Posted: 08.04.2012

COFFEE can give you the shakes, but caffeine seems to have the opposite effect in people with Parkinson's disease, helping to relieve tremors and get them back on the move. In the past, caffeine has been shown to reduce the risk of Parkinson's, but its effects have never been tested in people who already have the disease. Ronald Postuma of McGill University in Montreal, Canada, and colleagues gave 61 people with Parkinson's a 6-week course of pills containing the caffeine equivalent of about three cups of coffee every day, or a placebo. Only people in the caffeine group showed a significant improvement in tests for motor problems, such as the severity of their tremors, and general mobility (Neurology, DOI: 10.1212/WNL.0b013e318263570d). Motor problems associated with Parkinson's are caused by a lack of dopamine in areas of the brain where dopamine-producing cells are destroyed. Adenosine receptors normally inhibit the production of dopamine. Caffeine blocks adenosine receptors and so acts to boost available dopamine. Drugs that target adenosine receptors are already in clinical trials but caffeine could provide a cheaper alternative. © Copyright Reed Business Information Ltd.

Keyword: Parkinsons
Link ID: 17123 - Posted: 08.04.2012

By Laura Sanders A much-maligned molecule that is devastating in the brain may have therapeutic potential outside it. The sticky amyloid-beta protein, which piles up in the brains of people with Alzheimer’s disease, actually reverses paralysis in mice with symptoms of multiple sclerosis. The unexpected finding, published in the Aug. 1 Science Translational Medicine, could mean that A-beta or molecules like it may one day form the basis of a treatment for multiple sclerosis in people. In MS, rogue immune cells penetrate the brain and spinal cord and attack myelin, a substance that is necessary to keep neural impulses moving at full speed. Damage and inflammation from this attack can leave a person with paralysis, numbness, vision problems and extreme fatigue. A-beta is found in the brains of people with MS, but scientists do not know precisely what effect it has there, if any. To investigate that question, study coauthor Lawrence Steinman of Stanford University and colleagues tried injecting A-beta into mice’s abdomens, thinking it would worsen symptoms. “We expected that either nothing would happen or the disease would worsen because this is an infamous, villainous molecule,” he says. Instead, the mice got better. In several different kinds of mice designed to have symptoms similar to the human disease, A-beta injections into the body reduced paralysis and lowered brain inflammation. “The outcome was unmistakable,” Steinman says. © Society for Science & the Public 2000 - 2012

Keyword: Multiple Sclerosis; Alzheimers
Link ID: 17122 - Posted: 08.04.2012