Chapter 3. Neurophysiology: The Generation, Transmission, and Integration of Neural Signals

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The number of seizure patients in a northern Japanese fishing community devastated by the March 11, 2011 tsunami spiked in the weeks following the disaster, according to a Japanese study. The study, published in the journal Epilepsia, looked at 440 patient records from Kesennuma City Hospital, in a city that was devastated by the massive tsunami touched off by the 9.0 magnitude earthquake. Thirteen patients were admitted with seizures in the eight weeks after the disaster, but only one had been admitted in the two months before March 11. Previous research has linked stressful life-threatening disasters with an increased risk of seizures, but most case reports lacked clinical data with multiple patients. "We suggest that stress associated with life-threatening situations may enhance seizure generation," wrote lead author Ichiyo Shibahara, a staff neurosurgeon at Sendai Medical Center in northern Japan. But he added that stress itself is not a universal risk factor for seizures. "Most of the seizure patients had some sort of neurological disease before the earthquake," he said. His team examined medical records from patients admitted to the neurosurgery ward in the eight weeks before and after the March 11 disaster and compared them to the same time period each year between 2008 and 2010. In 2008, there were 11 seizure patients admitted between January 14 and May 15. In 2009, there were seven and in 2010, just four. © 2013 NBCNews.com

Keyword: Epilepsy; Aggression
Link ID: 17705 - Posted: 01.22.2013

A strong family history of seizures could increase the chances of having severe migraines, says a study in Epilepsia journal. Scientists from Columbia University, New York, analysed 500 families containing two or more close relatives with epilepsy. Their findings could mean that genes exist that cause both epilepsy and migraine. Epilepsy Action said it could lead to targeted treatments. Previous studies have shown that people with epilepsy are substantially more likely than the general population to have migraine headaches, but it was not clear whether that was due to a shared genetic cause. The researchers found that people with three or more close relatives with a seizure disorder were more than twice as likely to experience 'migraine with aura' than patients from families with fewer individuals with seizures. Migraine with aura is a severe headache preceded by symptoms such as seeing flashing lights, temporary visual loss, speech problems or numbness of the face. Dr Melodie Winawer, lead author of the study from Columbia University Medical Centre, said the findings had implications for epilepsy patients. "Our study demonstrates a strong genetic basis for migraine and epilepsy, because the rate of migraine is increased only in people who have close (rather than distant) relatives with epilepsy." BBC © 2013

Keyword: Epilepsy; Aggression
Link ID: 17657 - Posted: 01.07.2013

A simple eye test may offer a fast and easy way to monitor patients with multiple sclerosis (MS), medical experts say in the journal Neurology. Optical Coherence Tomography (OCT) is a scan that measures the thickness of the lining at the back of the eye - the retina. It takes a few minutes per eye and can be performed in a doctor's surgery. In a trial involving 164 people with MS, those with thinning of their retina had earlier and more active MS. The team of researchers from the Johns Hopkins University School of Medicine say larger trials with a long follow up are needed to judge how useful the test might be in everyday practice. The latest study tracked the patients' disease progression over a two-year period. Unpredictable disease Multiple sclerosis is an illness that affects the nerves in the brain and spinal cord causing problems with muscle movement, balance and vision. In MS, the protective sheath or layer around nerves, called myelin, comes under attack which, in turn, leaves the nerves open to damage. There are different types of MS - most people with the condition have the relapsing remitting type where the symptoms come and go over days, weeks or months. Usually after a decade or so, half of patients with this type of MS will develop secondary progressive disease where the symptoms get gradually worse and there are no or very few periods of remission. BBC © 2012

Keyword: Multiple Sclerosis; Aggression
Link ID: 17639 - Posted: 12.27.2012

By Laura Sanders A new computer simulation of the brain can count, remember and gamble. And the system, called Spaun, performs these tasks in a way that’s eerily similar to how people do. Short for Semantic Pointer Architecture Unified Network, Spaun is a crude approximation of the human brain. But scientists hope that the program and efforts like it could be a proving ground to test ideas about the brain. Several groups of scientists have been racing to construct a realistic model of the human brain, or at least parts of it. What distinguishes Spaun from other attempts is that the model actually does something, says computational neuroscientist Christian Machens of the Champalimaud Centre for the Unknown in Lisbon, Portugal. At the end of an intense computational session, Spaun spits out instructions for a behavior, such as how to reproduce a number it’s been shown. “And of course, that’s why the brain is interesting,” Machens says. “That’s what makes it different from a plant.” Like a digital Frankenstein’s monster, Spaun was cobbled together from bits and pieces of knowledge gleaned from years of basic brain research. The behavior of 2.5 million nerve cells in parts of the brain important for vision, memory, reasoning and other tasks forms the basis of the new system, says Chris Eliasmith of the University of Waterloo in Canada, coauthor of the study, which appears in the Nov. 30 Science. © Society for Science & the Public 2000 - 2012

Keyword: Robotics
Link ID: 17557 - Posted: 12.01.2012

High-resolution real-time images show in mice how nerves may be damaged during the earliest stages of multiple sclerosis. The results suggest that the critical step happens when fibrinogen, a blood-clotting protein, leaks into the central nervous system and activates immune cells called microglia. "We have shown that fibrinogen is the trigger," said Katerina Akassoglou, Ph.D., an associate investigator at the Gladstone Institute for Neurological Disease and professor of neurology at the University of California, San Francisco, and senior author of the paper published online in Nature Communications. Multiple sclerosis, or MS, is thought to be an autoimmune disease in which cells that normally protect the body against infections attack nerve cells in the brain and spinal cord, often leading to problems with vision, muscle strength, balance and coordination, thinking and memory. Typically during MS, the immune cells destroy myelin, a protective sheath surrounding nerves, and eventually leading to nerve damage. The immune attack also causes leaks in the blood-brain barrier, which normally separates the brain from potentially harmful substances in the blood. "Dr. Akassoglou has focused on the role of the blood-brain barrier leak in MS and has discovered that leakage of the blood clotting protein fibrinogen can trigger brain inflammation," said Ursula Utz, Ph.D., M.B.A., a program director at NIH's National Institute of Neurological Disorders and Stroke (NINDS). Microglia are cells traditionally thought to control immunity in the nervous system. Previous studies suggested that leakage of fibrinogen activates microglia.

Keyword: Multiple Sclerosis; Aggression
Link ID: 17549 - Posted: 11.28.2012

Published by drrubidium Out-of-control libido or drug habit? Take Nervine. Nervous, excitable, wakeful, or restless? Take Nervine. Over-the-counter Nervine wasn't a wonder drug, just a cocktail of the oldest class of sedatives - inorganic bromides. Nervine contained the most commonly used bromides - sodium bromide (NaBr), potassium bromide (KBr), and ammonium bromide (NH4Br). These particular bromides were once so popular that only aspirin sold better. The use of bromides to treat "nerves" was so prevalent that 'bromide' entered the lexicon of common speech. Instead of "calm down", people were instructed to "take a bromide". Instead of calling someone a 'bore', the term 'bromide' was a used to denote "a commonplace or tiresome person". Bromides may owe their sedative effect to a family connection. The element bromine is in the same chemical family as the element chlorine – the halogens. Being a chemical family, chlorine and bromine have similar properties. Both form single, negatively charged ions (monovalent anions) via oxidation-reduction reactions - chloride (Cl-) and bromide (Br-). Chloride is found in nearly all of our cells, having its own set cell membrane-crossing highways (chlorine channel). The regulated flow of chloride (as hydrated chloride) across neuron membranes is key to communication between neurons. Being family and all, bromide (as hydrated bromide) can travel along chloride's highways. But hydrated bromide is a teeny bit smaller than hydrated chloride, allowing hydrated bromide to get into cells faster than hydrated chloride. A flood of anions, such as bromide or chloride, into a neuron makes it more negative than it would be at rest, a state called 'hyperpolarization'. It's hard for other neutrons to stimulate - talk to - hyperpolarized neurons. Less neuron stimulation can translate to a feeling of calm. Thirty-Seven Copyright © 2012

Keyword: Drug Abuse
Link ID: 17535 - Posted: 11.26.2012

A substance made by the body when it uses fat as fuel could provide a new way of treating epilepsy, experts hope. Researchers in London who have been carrying out preliminary tests of the fatty acid treatment, report their findings in Neuropharmacology journal. They came up with the idea because of a special diet used by some children with severe, drug resistant epilepsy to help manage their condition. The ketogenic diet is high in fat and low in carbohydrate. The high fat, low carbohydrate diet is thought to mimic aspects of starvation by forcing the body to burn fats rather than carbohydrates. Although often effective, the diet has attracted criticism, as side-effects can be significant and potentially lead to constipation, hypoglycaemia, retarded growth and bone fractures. By pinpointing fatty acids in the ketogenic diet that are effective in controlling epilepsy, researchers hope they can develop a pill for children and adults that could provide similar epilepsy control without the side-effects. In early trials, the scientists, from Royal Holloway and University College London, say they have identified fatty acids that look like good candidates for the job. They found that not only did some of the fatty acids outperform a regular epilepsy medication called valproate in controlling seizures in animals, they also had fewer side-effects. BBC © 2012

Keyword: Epilepsy; Aggression
Link ID: 17533 - Posted: 11.24.2012

By David Pogue Okay, great: we can control Our phones with speech recognition and our television sets with gesture recognition. But those technologies don't work in all situations for all people. So I say, forget about those crude beginnings; what we really want is thought recognition. As I found out during research for a recent NOVA episode, it mostly appears that brain-computer interface (BCI) technology has not advanced very far just yet. For example, I tried to make a toy helicopter fly by thinking “up” as I wore a $300 commercial EEG headset. It barely worked. Such “mind-reading” caps are quick to put on and noninvasive. They listen, through your scalp, for the incredibly weak remnants of electrical signals from your brain activity. But they're lousy at figuring out where in your brain they originated. Furthermore, the headset software didn't even know that I was thinking “up.” I could just as easily have thought “goofy” or “shoelace” or “pickle”—whatever I had thought about during the 15-second training session. There are other noninvasive brain scanners—magnetoencephalography, positron-emission tomography and near-infrared spectroscopy, and so on—but each also has its trade-offs. Of course, you can implant sensors inside someone's skull for the best readings of all; immobilized patients have successfully manipulated computer cursors and robotic arms using this approach. Still, when it comes to controlling everyday electronics, brain surgery might be a tough sell. © 2012 Scientific American,

Keyword: Robotics
Link ID: 17518 - Posted: 11.21.2012

By Maggie Fox, NBC News Researchers trying to find a way to treat multiple sclerosis think they’ve come up with an approach that could not only help patients with MS, but those with a range of so-called autoimmune diseases, from type-1 diabetes to psoriasis, and perhaps even food allergies. So far it’s only worked in mice, but it has worked especially well. And while mice are different from humans in many ways, their immune systems are quite similar. “If this works, it is going to be absolutely fantastic,” said Bill Heetderks, who directs outside research at the National Institute of Biomedical Imaging and Bioengineering, part of the National Institutes of Health, which helped pay for the research. “Even if it doesn’t work, it’s going to be another step down the road.” In autoimmune disease, the body’s immune cells mistakenly attack and destroy healthy tissue. In MS, it’s the fatty protective sheath around the nerves; in type-1 or juvenile diabetes it’s cells in the pancreas that make insulin; in rheumatoid arthritis it’s tissue in the joint. Currently, the main treatment is to suppress the immune system, an approach that can leave patients vulnerable to infections and cancer. The new treatment re-educates the immune cells so they stop the attacks. The approach uses tiny little balls called nanoparticles made of the same material used to make surgical sutures that dissolve harmlessly in the body. They’re attached to little bits of the protein that the immune cells are attacking, the researchers report in Sunday’s issue of the journal Nature Biotechnology. © 2012 NBCNews.com

Keyword: Multiple Sclerosis; Aggression
Link ID: 17508 - Posted: 11.19.2012

Sandrine Ceurstemont, editor, New Scientist TV Improving your mathematical skills could now be as easy as playing a Kinect video game in a hat. In preliminary tests of the system, developed by Roi Cohen Kadosh and colleagues from the University of Oxford, participants were better with numbers after just two days of training. In this video, our technology features editor Sally Adee gives the game a go while testing a new cap that wirelessly delivers electrical brain stimulation. The device is controlled by a computer, which controls things like the duration of the zapping. Although it can stimulate various brain regions, in this case it sends current to the right parietal cortex. "The parietal region is involved in numerical understanding," says Cohen Kadosh. "So amplifying the function of this region should lead to a better performance." So far, the team has shown that brain stimulation while doing computer-based mathematics exercises helped maintain better mathematical skills in adults even six months later. But Cohen Kadosh thinks that the Kinect game is much more promising as a training tool because it's fun and engaging. By requiring a player to represent a fraction by moving their body to position it on a line, the gameplay also integrates three key components linked to mathematical ability: numerical understanding, the ability to perceive the spatial relationship of visual representations and embodiment. Cohen Kadosh believes this enhances the training. © Copyright Reed Business Information Ltd

Keyword: Intelligence; Aggression
Link ID: 17500 - Posted: 11.17.2012

By James Gallagher Health and science reporter, BBC News Adding "calm down" genes to hyperactive brain cells has completely cured rats of epilepsy for the first time, say UK researchers. They believe their approach could help people who cannot control their seizures with drugs. The study, published in the journal Science Translation Medicine, used a virus to insert the new genes into a small number of neurons. About 50 million people have epilepsy worldwide. However, drugs do not work for up to 30% of them. The alternatives include surgery to remove the part of the brain that triggers a fit or to use electrical stimulation. The brain is alive with electrical communication with individual neurons primed to fire off new messages. However, if a group of neurons become too excited they can throw the whole system into chaos leading to an epileptic seizure. Researchers at University College London have developed two ways of manipulating the behaviour of individual cells inside the brain in order to prevent those seizures. Both use viruses injected into the brain to add tiny sections of DNA to the genetic code of just a few thousand neurons. One method boosts the brain cells' natural levels of inhibition in order to calm them down. This treatment is a form of gene therapy, a field which is often criticised for failing to deliver on decades of promise. BBC © 2012

Keyword: Epilepsy; Aggression
Link ID: 17482 - Posted: 11.13.2012

Seizures during childhood fever are usually benign, but when prolonged, they can foreshadow an increased risk of epilepsy later in life. Now a study funded by the National Institutes of Health suggests that brain imaging and recordings of brain activity could help identify the children at highest risk. The study reveals that within days of a prolonged fever-related seizure, some children have signs of acute brain injury, abnormal brain anatomy, altered brain activity, or a combination. "Our goal has been to develop biomarkers that will tell us whether or not a particular child is at risk for epilepsy. This could in turn help us develop strategies to prevent the disorder," said study investigator Shlomo Shinnar, M.D., Ph.D. Dr. Shinnar is a professor of neurology, pediatrics and epidemiology and the Hyman Climenko Professor of Neuroscience Research at Montefiore Medical Center, Albert Einstein College of Medicine, New York City. Seizures that occur during the course of a high fever, known as febrile seizures, affect 3 to 4 percent of all children. Most such children recover rapidly and do not suffer long-term health consequences. However, having one or more prolonged febrile seizures in childhood is known to increase the risk of subsequent epilepsy. Some experts estimate that the risk of later epilepsy is 30-40 percent following febrile status epilepticus (FSE), a seizure or series of seizures that can last from 30 minutes to several hours. "While the majority of children fully recover from febrile status epilepticus, some will go on to develop epilepsy. We have no way of knowing yet who they will be," Dr. Shinnar said.

Keyword: Epilepsy; Aggression
Link ID: 17469 - Posted: 11.08.2012

By James Gallagher Health and science reporter, BBC News A new drug is the "most effective" treatment for relapsing-remitting multiple sclerosis, say UK researchers. During MS the body's immune system turns on its own nerves causing debilitating muscle problems. Researchers at the University of Cambridge say a cancer drug, which wipes out and resets the immune system, has better results than other options. However, there is concern that a drugs company is about to increase the cost of the drug as a result. Around 100,000 people in the UK have multiple sclerosis. When the condition is diagnosed most will have a form of the disease know as relapsing-remitting MS, in which the symptoms can almost disappear for a time, before suddenly returning. Built from scratch The researchers tested a leukaemia drug, alemtuzumab, which had shown benefits for MS in small studies. In leukaemia, a blood cancer, it controls the excess production of white blood cells. In MS patients, the dose eliminates the immune cells entirely, forcing a new immune system to be built from scratch which should not attack the nerves. Two trials, published in the Lancet medical journal, compared the effectiveness of alemtuzumab with a first-choice drug, interferon beta-1a. BBC © 2012

Keyword: Multiple Sclerosis; Aggression
Link ID: 17450 - Posted: 11.03.2012

By Laura Sanders A genetic tweak makes it easier to see neurons at work in living, breathing animals. The method, described in the Oct. 18 Neuron, capitalizes on a property of a busy neuron: When the cell fires, calcium ions flood in. Using an altered version of the protein GFP that lights up when calcium is present in a mouse’s brain, neuroscientist Guoping Feng of MIT and colleagues could see smell-sensing neurons respond to an odor, and movement neurons light up during walking. Q. Chen et al. Imaging Neural Activity Using Thy1-GCaMP Transgenic Mice. Neuron. Vol. 76, October 18,2012, p. 297. doi: 10.1016/j.neuron.2012.07.011. [Go to] © Society for Science & the Public 2000 - 2012

Keyword: Brain imaging
Link ID: 17435 - Posted: 10.30.2012

David Cyranoski More than a decade of research hinting that magnesium supplements might boost your brain power is finally being put to the test in a small clinical trial. The research, led by biopharmaceutical company Magceutics of Hayward, California, began testing the ability of its product Magtein to boost magnesium ion (Mg2+) levels in the brain earlier this month. The trial will track whether the ions can decrease anxiety and improve sleep quality, as well as following changes in the memory and cognitive ability of participants. But critics caution that the trial in just 50 people is too small to draw definitive conclusions. Neuroscientist Guosong Liu of the Massachusetts Institute of Technology in Cambridge, who founded Magceutics, plans eventually to test whether Magtein can be used to treat a wider range of conditions, including attention deficit hyperactivity disorder (ADHD) and Alzheimer’s disease. But Liu knows that it will be difficult to convince other scientists that something as simple as a magnesium supplement can have such profound effects. It is almost “too good to be true”, he says. Many scientists contacted by Nature agreed with that sentiment. One clinical researcher cautioned against “over-excitement about a magic drug for a major disorder”. And others wonder whether the study will even be able to prove anything conclusively. “I am very sceptical that the proposed trial will provide the answer to the question being tested,” says Stephen Ferguson, a biochemist at the University of Western Ontario in London, Ontario. © 2012 Nature Publishing Group

Keyword: Learning & Memory; Aggression
Link ID: 17430 - Posted: 10.27.2012

by Emily Underwood Four young boys with a rare, fatal brain condition have made it through a dangerous ordeal. Scientists have safely transplanted human neural stem cells into their brains. Twelve months after the surgeries, the boys have more myelin—a fatty insulating protein that coats nerve fibers and speeds up electric signals between neurons—and show improved brain function, a new study in Science Translational Medicine reports. The preliminary trial paves the way for future research into potential stem cell treatments for the disorder, which overlaps with more common diseases such as Parkinson's disease and multiple sclerosis. "This is very exciting," says Douglas Fields, a neuroscientist at the National Institutes of Health in Bethesda, Maryland, who was not involved in the work. "From these early studies one sees the promise of cell transplant therapy in overcoming disease and relieving suffering." Without myelin, electrical impulses traveling along nerve fibers in the brain can't travel from neuron to neuron says Nalin Gupta, lead author of the study and a neurosurgeon at the University of California, San Francisco (UCSF). Signals in the brain become scattered and disorganized, he says, comparing them to a pile of lumber. "You wouldn't expect lumber to assemble itself into a house," he notes, yet neurons in a newborn baby's brain perform a similar feat with the help of myelin-producing cells called oligodendrocytes. Most infants are born with very little myelin and develop it over time. In children with early-onset Pelizaeus-Merzbacher disease, he says, a genetic mutation prevents oligodendrocytes from producing myelin, causing electrical signals to die out before they reach their destinations. This results in serious developmental setbacks, such as the inability to talk, walk, or breathe independently, and ultimately causes premature death. © 2010 American Association for the Advancement of Science

Keyword: Stem Cells; Aggression
Link ID: 17356 - Posted: 10.11.2012

by Michael Marshall THE human brain might be the most complex object in the known universe, but a much simpler set of neurons is also proving to be a tough nut to crack. A tiny wasp has brain cells so small, physics predicts they shouldn't work at all. These miniature neurons might harbour subtle modifications, or they might work completely differently from all other known neurons - mechanically. The greenhouse whitefly parasite (Encarsia formosa) is just half a millimetre in length. It parasitises the larvae of whiteflies and so it has long been used as a natural pest-controller. To find out how its neurons have adapted to miniaturisation, Reinhold Hustert of the University of Göttingen in Germany examined the insect's brain with an electron microscope. The axons - fibres that shuttle messages between neurons - were incredibly thin. Of 528 axons measured, a third were less than 0.1 micrometre in diameter, an order of magnitude narrower than human axons. The smallest were just 0.045 μm (Arthropod Structure & Development, doi.org/jfn). That's a surprise, because according to calculations by Simon Laughlin of the University of Cambridge and colleagues, axons thinner than 0.1 μm simply shouldn't work. Axons carry messages in waves of electrical activity called action potentials, which are generated when a chemical signal causes a large number of channels in a cell's outer membrane to open and allow positively charged ions into the axon. At any given moment some of those channels may open spontaneously, but the number involved isn't enough to accidentally trigger an action potential, says Laughlin - unless the axon is very thin. An axon thinner than 0.1 μm will generate an action potential if just one channel opens spontaneously (Current Biology, doi.org/frfwpz). © Copyright Reed Business Information Ltd

Keyword: Miscellaneous; Aggression
Link ID: 17335 - Posted: 10.06.2012

Analysis by Tracy Staedter From the department of "I hope this never happens to me," scientists have used a laser to manipulate the behavior of a worm. First, a research team from the Howard Hughes Medical Institute genetically engineered a tiny, transparent worm called Caenorhabditis elegans to have neurons that give off fluorescent light. This allowed the neurons to be tracked during experiments. The scientists also engineered the neurons to be sensitive to light, which made it possible to activate them with pulses of laser light. Next, they built a movable table for the worm to crawl on, keeping it aligned beneath a camera and laser. They used the laser to activate a single neuron at a time. By doing so, they were able to control a worm's behavior and its senses. In tests, which the researchers published in the journal Nature, the laser made the worm turn left or right and move through a loop. The laser also tricked the worm brain into thinking food was nearby. The worm, in turn, wiggled toward what it thought was a meal. The research, which on the surface seems like a bit of a circus, actually is important because it shows scientists which neurons are responsible for what. "If we can understand simple nervous systems to the point of completely controlling them, then it may be a possibility that we can gain a comprehensive understanding of more complex systems," said Sharad Ramanathan, an Assistant Professor of Molecular and Cellular Biology, and of Applied Physics. "This gives us a framework to think about neural circuits, how to manipulate them, which circuit to manipulate and what activity patterns to produce in them." © 2012 Discovery Communications, LLC

Keyword: Development of the Brain
Link ID: 17299 - Posted: 09.26.2012

By Nathan Seppa People with multiple sclerosis might soon have a new option for controlling their disease with pills instead of shots. Two studies in the Sept. 20 New England Journal of Medicine demonstrate that a variation on a drug used against psoriasis for years in Germany holds off MS relapses and has minimal side effects. “These data look good. Both studies show a reduction in relapses with really pretty robust effects,” says Clyde Markowitz, a neurologist at the University of Pennsylvania who wasn’t involved with the trials. The drug, called BG-12, has been submitted to the U.S. Food and Drug Administration for approval by the biotech company Biogen Idec. Markowitz expects it to get approved. “It would be a clear benefit to the MS population to have another option,” he says. If approved, BG-12 would be the third oral drug available to treat MS. The disease results when the immune system attacks the fatty myelin sheaths coating nerves in the central nervous system, leading to impaired muscle control, balance, vision and speech. BG-12, or dimethyl fumarate, has anti-inflammatory, cell-protective and antioxidant effects, which earlier work suggested could suppress the aberrant immune reactions in MS patients. Scientists in both studies recruited MS patients and randomly assigned some in each group to BG-12 or placebo tablets. In one of the studies, an additional group was randomly assigned to get an injectable MS drug called glatiramer acetate (Copaxone). In other respects the studies were nearly identical, each enrolling more than 1,000 MS patients, ages 18 to 55, in 28 countries apiece, for two years of treatment. Both trials included a mix of North American and European researchers. © Society for Science & the Public 2000 - 2012

Keyword: Multiple Sclerosis
Link ID: 17284 - Posted: 09.22.2012

by Douglas Heaven The versatile cannabis plant may have a new use: it could be used to control epileptic seizures with fewer side effects than currently prescribed anti-convulsants. Ben Whalley at the University of Reading, UK, and colleagues worked with GW Pharmaceuticals in Wiltshire, UK, to investigate the anti-convulsant properties of cannabidivarin (CBDV), a little-studied chemical found in cannabis and some other plants. There is "big, historical, anecdotal evidence" that cannabinoids can be used to control human seizures, says Whalley, but the "side-effect baggage" means there have been relatively few studies of its pharmaceutical effect on this condition. The team investigated the effectiveness of CBDV – one of around 100 non-psychoactive cannabinoids found in cannabis – as an anti-convulsant. They induced seizures in live rats and mice that had been given the drug. These animals experienced less severe seizures and lower mortality compared with animals given a placebo. The drug also had fewer side effects and was better tolerated than three of the most widely prescribed anticonvulsants. Epileptic seizures affect about one per cent of the population. Left uncontrolled, they can lead to depression, cognitive decline and death. If you control the seizures, says Whalley, "the chances of death drop away completely". The decision about whether to test the drug in humans will be made next year. © Copyright Reed Business Information Ltd

Keyword: Epilepsy; Aggression
Link ID: 17255 - Posted: 09.13.2012