Links for Keyword: Stroke

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Helen Thomson, biomedical news editor, San Diego This weekend I was shown how a virtual reality piano has helped people who have had a stroke regain movement in their limbs. This game, and others like it, aid the functional reorganisation of the brain and could pave the way for faster improvements in stroke therapy. Soha Saleh, at the New Jersey Institute of Techonology, and colleagues used a robotic glove, together with various video games, to train four volunteers who had suffered stroke and lost near-total movement of their upper limbs. The four subjects were trained for 3 hours a day over 8 days. Each training session involved making finger and hand movements with the aid of a robotic glove which gave a small amount of support to volunteers' mobility, such as holding groups of fingers together so that the volunteer could concentrate on moving just one. The volunteers were instructed on what movements to perform by playing computer games involving stacking items on a shelf or playing tunes on a piano. Their movements were transmitted into the video game to provide immediate visual feedback. The subjects were tested for breadth of movement and questioned on their ability to perform everyday tasks before and after the training sessions. All four participants showed improvements in movement after the task, with an average improvement of 24 per cent in tasks such as reaching for ones nose. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 14677 - Posted: 11.16.2010

Taking vitamin E could slightly increase the risk of a particular type of stroke, a study says. The British Medical Journal study found that for every 1,250 people there is the chance of one extra haemorrhagic stroke - bleeding in the brain. Researchers from France, Germany and the US studied nine previous trials and nearly 119,000 people. But the level at which vitamin E becomes harmful is still unknown, experts say. The study was carried out at Harvard Medical School, Boston, and INSERM in Paris. Haemorrhagic strokes are the least common type and occur when a weakened blood vessel supplying the brain ruptures and causes brain damage. Researchers found that vitamin E increased the risk of this kind of stroke by 22%. The study also found that vitamin E could actually cut the risk of ischaemic strokes - the most common type of stroke - by 10%. Ischaemic strokes account for 70% of all cases and happen when a blood clot prevents blood reaching the brain. Experts found vitamin E could cut the risk, equivalent to one ischaemic stroke prevented per 476 people taking the vitamin. BBC © MMX

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 14632 - Posted: 11.06.2010

by Karen Heyman One-third of stroke survivors never recover enough brain function to live on their own. Now scientists think they know why. Once a stroke kills a swath of brain cells, a neurotransmitter known as GABA impairs the surviving, apparently healthy, brain tissue. Targeting GABA could help a stroke-afflicted brain better overcome its damage, the researchers suggest. When a stroke hits, physicians have few options. If they catch it early enough, they can administer the clot-busting drug tPA to keep even more brain cells from dying—but tPA is not appropriate for all types of stroke. Physicians can also prescribe physical therapy, which can occasionally help recover impaired motor function. Yet there are no approved drugs that help the brain heal. For its part, the brain appears to try a sort of natural drug therapy to limit the spread of damage. It releases extra amounts of GABA, which reduces the firing of neurons. GABA initially prevents stroke-damaged brain tissue from becoming overexcited and dying. But University of California, Los Angeles (UCLA), investigators led by Thomas Carmichael, a specialist in stroke, and Istvan Mody, an expert in inhibition, wondered whether GABA might also interfere with the brain's plasticity, the ability of healthy regions to take over for injured ones. Previous studies had tried to address this question, but they produced confusing results. The UCLA team hypothesized that others had failed to distinguish between two types of inhibition—phasic, in which GABA acts upon specific receptors at nerve cell sites called synapses, and tonic, in which the neurotransmitter acts on other receptors elsewhere on the nerve cell. © 2010 American Association for the Advancement of Science.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 15: Language and Our Divided Brain; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 14626 - Posted: 11.04.2010

By Nathan Seppa MRI scans of stroke patients can indicate when the stroke occurred, a revelation that could allow more aggressive treatment to limit brain damage, French researchers report online November 2 in Radiology. For a person arriving at a hospital with a stroke, the clock is ticking. When a clot obstructs an artery in the brain, millions of neurons are lost with each passing minute as tissue is starved of blood and oxygen. A clot-busting drug called tPA, or tissue plasminogen activator, can often dissolve the clot and free up the vessel. But the drug is generally considered safe to administer only in the first three to 4½ hours after a stroke begins (SN: 10/25/08, p. 16). Stoke patients typically get a CT scan, which enables doctors to discern whether the stroke results from a blood clot or, less commonly, from a hemorrhage, which shows up as a dark mass on the CT, says neurologist Andrew Barreto of the University of Texas Medical School at Houston. MRI, or magnetic resonance imaging, is used much less often and usually only at large medical centers. Unfortunately, a CT scan cannot pinpoint when a stroke began. Neither can many patients, either because they can’t recall exactly when their symptoms first appeared or because they woke up already in the throes of a stroke. In such cases, doctors “guesstimate” the stroke’s onset, Barreto says, but hesitate to give tPA if too many hours might have passed. Giving tPA too late won’t help tissue that’s already dead and risks causing a brain bleed. After the tPA window closes there is little doctors can do but monitor the patient. © Society for Science & the Public 2000 - 2010

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 15: Language and Our Divided Brain; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 14625 - Posted: 11.04.2010

Nicole Baute Living Reporter Stroke victims are 12 per cent more likely to die within seven days if they arrive at the hospital on the weekend, according to a study of more than 20,000 Ontario patients. The study, published today in Neurology, found that patients received the same major interventions — brain scans, clot-busting medications and admission to stroke units — regardless of when they were admitted. Dr. Moira Kapral, a researcher at the Institute for Clinical Evaluative Sciences and one of the study’s authors, says it is possible that the weekend effect is caused by “an accumulation of small deficiencies in care” — including secondary treatment that is nonetheless crucial for recovery. For example, she says, there might be fewer or less-experienced staff working on the weekends. Or patients might experience delays in access to rehabilitation experts, such as physiotherapists who help stroke patients regain mobility or speech pathologists who do swallowing assessments to determine whether or not it’s safe to eat. Further research is necessary to examine these possibilities. In the meantime, says Kapral, health-care administrators should try to determine what is causing the increased mortality gap. “I think hospitals should really look at their weekend practices in terms of staffing and resources to see if there are things that can be done to improve care on weekends.” © Copyright Toronto Star 1996-2010

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 14620 - Posted: 11.04.2010

A new stroke prevention clinic in Ottawa is helping patients treated for mini-strokes from developing the full-blown version, doctors report. A transient ischemic attack, or TIA, is a mild stroke that causes stroke symptoms such as sudden numbness of the face, arm or leg. The symptoms last for less than 24 hours and then resolve on their own without disabling neurological effects, but it is a marker for early risk of stroke. At the Ottawa Hospital Stroke Clinic, patients with TIA symptoms are quickly assessed in the emergency department (ED) and referred to the stroke clinic for brain imaging, medication adjustment, counselling about stroke risk factors and surgery in some cases. Dr. Mukul Sharma, deputy director of the Canadian Stroke Network, and his co-authors found that 3.2 per cent of people who experienced TIA at the stroke prevention clinic developed a full-blown stroke within 90 days, compared with about 10 per cent at other centres. "The beauty of this is that we added very few staff," said Sharma, lead author of the study in the November issue of the journal Stroke, and director of The Ottawa Hospital Stroke Clinic. A booking clerk was one of the few staff that was added as part of the program. "It really is that ability to juggle bookings and the acuity of the visit that I think make this process work. I've likened it to getting an orchestra playing the same tune." © CBC 2010

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 14608 - Posted: 10.30.2010

Lauran Neergaard, Associated Press - When her stroke hit, Edna Wooten somehow stopped her car. Then her daughter ignored her slurred protests and raced her to the hospital - in time for a drug to dissolve the blood clot causing her stroke. Wooten was lucky: Too few stroke sufferers get that clot-busting treatment, especially black and Latino patients who are at highest risk of having a stroke and also may be hesitant to seek fast care. New research is targeting those underserved populations to better spread the word that "time is brain" - the faster you move, the more brain you save. "We basically scare people so much about stroke, it motivates them to denial," says Dr. Lewis Morgenstern of the University of Michigan, an expert on stroke disparities. "What we haven't done a good job of is telling people there is an effective treatment, that people are in control of their own destiny." That was the message that stroke educator Shauna St. Clair of Georgetown University took to a senior center in a predominantly black neighborhood in Washington last week, part of a project funded by the National Institutes of Health. "Damaged brain cells we can fix. That's why we want you to get treatment as soon as possible," St. Clair told the rapt group. "If they stay damaged, they die." © 2010 Hearst Communications Inc.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 14555 - Posted: 10.14.2010

By Nathan Seppa The dismal range of options for treating a stroke might be improving. Scientists report that neutralizing an enzyme called NOX4 that shows up in stroke-damaged tissues can limit brain injury in mice. The study appears in the September PLoS Biology. Stroke treatment is often hampered because the primary available drug, a clot-buster called tPA, is effective only within three hours of a stroke’s onset; many strokes are not detected until after that window has closed. Knowing the molecular culprits involved in brain tissue damage caused by a stroke might give scientists another angle to exploit as they seek treatments, says Harald Schmidt, a physician and pharmacologist at Maastricht University in the Netherlands. To that end, Schmidt teamed with an international group of scientists to study the role of NOX4, a member of an enzyme family that makes free radicals — highly reactive molecules that can kill cells and contribute to tissue damage. The researchers induced strokes in mice by threading a filament up an artery into the brain to a point at which it obstructed the vessel. In a series of experiments, the scientists found that mice genetically engineered to lack the NOX4 enzyme showed substantially less damage from these strokes than mice making NOX4. In other tests, normal mice with the ability make the NOX enzymes fared better against strokes when given an experimental drug that neutralized NOX4 than did mice not receiving the drug. © Society for Science & the Public 2000 - 2010

Related chapters from BP7e: Chapter 1: Biological Psychology: Scope and Outlook; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 1: An Introduction to Brain and Behavior; Chapter 15: Language and Our Divided Brain
Link ID: 14483 - Posted: 09.23.2010

By Carolyn Y. Johnson In the ever-expanding world of medical devices, early adopters have a new option: a robotic arm. A Cambridge start-up, Myomo Inc., is making an expensive stroke therapy available directly to patients, an effort to encourage use of the novel device. The Myomo arm, based on technology developed at the Massachusetts Institute of Technology, is in many ways a natural extension of research that has shown repetitive-exercise therapy can help stroke patients regain movement. The lightweight prosthesis straps onto the arm and reads signals from the muscles to give a patient an assist when he or she moves the limb. But there is no rigorous scientific evidence demonstrating how well it works. And the $7,000 device casts a spotlight on the hard-to-navigate world of rehabilitation devices — in which patients who are often desperate face a growing number of products whose effectiveness is still being determined. “While there’s some suggestive, tiny studies — that are really pilot studies — that it might be useful, there’s no proof of efficacy using the usual criteria,’’ said Dr. Joel Stein, chairman of the rehabilitation and regenerative medicine department at Columbia University. He is also on Myomo’s scientific advisory board. “I’ve worked with many stroke patients through the years, and I’m careful to not be too paternalistic deciding for them. . . . They feel like the medical system has given up on them, and there’s a fine line between not over-promising and saying we have nothing shown to be helpful, therefore you should just give up.’’ © 2010 NY Times Co

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 15: Language and Our Divided Brain; Chapter 5: The Sensorimotor System
Link ID: 14337 - Posted: 08.09.2010

by Linda Geddes, Amsterdam THE discovery of an antibody that binds to certain brain receptors could reduce the side effects of a common stroke drug and buy additional time in which to use it. The preferred treatment for ischaemic stroke, in which a blood clot cuts off the blood supply to brain tissue, is a drug called rtPA, which dissolves the clot. However, that drug has to be given within the first few of hours of a stroke, otherwise the risks of treatment outweigh the benefits. Dissolving the clot can lead to a sudden rise in blood pressure, increasing the chance that a blood vessel will rupture and bleed into the brain. Only 5 to 10 per cent of people who suffer a stroke make it to hospital early enough to be treated with rtPA, says Denis Vivien of the University of Caen Basse-Normandie in France. The rest are given drugs that do not destroy the initial clot but reduce the chance of further clots forming. One reason for a delay in administering rtPA is that a brain scan must be carried out to determine the nature of the stroke. People with haemorrhagic stroke, in which a blood vessel in the brain bursts, should not receive rtPA as it increases the risk of bleeding. Now a startling discovery by Vivien has put a different perspective on this relatively simple picture: rtPA is actually released by brain cells. "This was completely unexpected," he says. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 14243 - Posted: 07.10.2010

By JONATHAN DIENST My son Jared lay in a bed at NewYork-Presbyterian/Weill Cornell hospital, limp and pale, his 7-year-old body tethered to a tangle of tubes and monitor wires. A neurologist, Dr. Maurine Packard, stood to his left. “Jared,” I recall her saying. “Pay attention to what I say.” And then, in a strong, firm voice: “The barn is red.” She waited a few moments and asked, “What color is the barn?” Jared started to answer, then froze. My wife and I, sitting behind Dr. Packard, froze too. Two days before, he had been a happy, athletic second grader, a beautiful boy who loved playing baseball and basketball in the park. Now he couldn’t walk; he had to struggle to remember the color of a barn. He tried again, and then replied in a weak, slurred voice. “No,” Jared said. Dr. Packard nodded, as if that was the answer she had expected. Before June 23, 2008, my wife, Victoria, and I had never heard of a child’s having a stroke. Most people, many doctors included, still haven’t. In the agonizing months that followed, we heard it over and over: “But children don’t have strokes.” How little we knew. It turns out that stroke, by some estimates, is the sixth leading cause of death in infants and children. And experts say doctors and hospitals need to be far more aggressive in detecting and treating it. Copyright 2010 The New York Times Company

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 15: Language and Our Divided Brain
Link ID: 13689 - Posted: 06.24.2010

By RONI CARYN RABIN Residents of the Southeast are so much more likely than other Americans to die of a stroke that epidemiologists call the region the “stroke belt.” A new study suggests that the risk may be established early in life, because even when those born in the South relocate to another region as adults, they carry the increased risk of stroke with them. Harvard School of Public Health researchers who analyzed stroke deaths across the United States found that people who were born in the Southeast and continued to live there as adults were 34 percent more likely than other Americans to die of a stroke in the year 2000. But even those who moved away faced an increased risk, with whites 20 percent more likely and blacks 9 percent more likely to die of a stroke than Americans who lived their entire lives outside the region, the study found. The stroke belt includes Alabama, Arkansas, Georgia, Mississippi, North Carolina, South Carolina and Tennessee. The study, published in the Dec. 1 issue of the journal Neurology, analyzed death rates from 1980, 1990 and 2000. Though stroke death rates declined over time, the study found consistent patterns of elevated risk through the decades. Copyright 2009 The New York Times Company

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 15: Language and Our Divided Brain; Chapter 13: Memory, Learning, and Development
Link ID: 13530 - Posted: 06.24.2010

Vitamin E supplements do not protect healthy women against heart attacks and stroke, according to new results from the Women’s Health Study, a long-term clinical trial of the effect of vitamin E and aspirin on both the prevention of cardiovascular disease and of cancer. The vitamin E results of the Women’s Health Study are published in the July 6 issue of the Journal of the American Medical Association. In addition to the cardiovascular disease findings, the study authors report that there was no effect of vitamin E on total cancer or on the most common cancers in women — breast, lung, and colon cancers. The Women’s Health Study was funded by the National Heart, Lung, and Blood Institute (NHLBI) and the National Cancer Institute of the National Institutes of Health. “This landmark trial has given women and their physicians important health information. We can now say that despite their initial promise, vitamin E supplements do not prevent heart attack and stroke. Instead, women should focus on well proven means of heart disease prevention, including leading a healthy lifestyle and controlling risk factors such as high blood pressure and high cholesterol,” said NHLBI Director Elizabeth G. Nabel, M.D. The Women’s Health Study was conducted between 1992 and 2004. The participants were 39,876 healthy women age 45 years and older who were randomly assigned to receive 600 IU of Vitamin E or placebo and low-dose aspirin or placebo on alternate days. The participants were followed for an average of 10.1 years. The aspirin results published last March found no benefit of aspirin (100 mg every other day) in preventing first heart attacks or death from cardiovascular causes in women but did find a reduced risk of stroke overall, as well as reduced risk of both stroke and heart attack in women aged 65 and older.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 7597 - Posted: 06.24.2010

ST. PAUL, MN - Public education is needed about the symptoms and risks of mini-stroke, also called transient ischemic attack or TIA, according to the first large study on the topic, which is published in the May 13 issue of Neurology, the scientific journal of the American Academy of Neurology. The study found that only 9 percent of people could give the definition of a TIA or identify a symptom of TIA. TIA symptoms are the same as those for a regular stroke, but TIA symptoms resolve themselves within 24 hours. The phone survey of more than 10,000 people found that 3.2 percent had TIA symptoms but never saw a physician about them. Among those with a TIA diagnosis, 16 percent saw the doctor more than a week after the symptoms occurred. “People think that because these symptoms go away quickly, they don’t need to worry about them, but that’s definitely not the case,” said study author and neurologist S. Claiborne Johnston, MD, PhD, of the University of California, San Francisco. “People who’ve had a TIA are at high risk of having a stroke, particularly in the first few days after the TIA, and doctors can help them reduce that risk. ”

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 3830 - Posted: 06.24.2010

Dr. Cesario V. Borlongan, neuroscientist, is trying to determine if a compound that is elevated in hibernating squirrels can one day help avoid the ravages of stroke and Parkinson's disease.] A compound that enables squirrels to hibernate may one day help minimize brain damage that results from stroke, according to a researcher at the Medical College of Georgia and Veterans Affairs Medical Center in Augusta. In an animal model for stroke, delta opioid peptide reduced by as much as 75 percent the damage to the brain’s striatum, the deeper region of the brain and a major target for strokes, according to Dr. Cesario V. Borlongan, neuroscientist. In fact, evidence suggests that the compound, which puts cells in a temporary state of suspended animation, may help protect brain cells from the ravages of Parkinson’s disease as well. Copyright 2002 Medical College of Georgia. All rights reserved.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 15: Language and Our Divided Brain
Link ID: 2912 - Posted: 06.24.2010

By GINA KOLATA Dr. Diana Fite, a 53-year-old emergency medicine specialist in Houston, knew her blood pressure readings had been dangerously high for five years. But she convinced herself that those measurements, about 200 over 120, did not reflect her actual blood pressure. Anyway, she was too young to take medication. She would worry about her blood pressure when she got older. Then, at 9:30 the morning of June 7, Dr. Fite was driving, steering with her right hand, holding her cellphone in her left, when, for a split second, the right side of her body felt weak. “I said: ‘This is silly, it’s my imagination. I’ve been working too hard.’ ” Suddenly, her car began to swerve. “I realized I had no strength whatsoever in my right hand that was holding the wheel,” Dr. Fite said. “And my right foot was dead. I could not get it off the gas pedal.” She dropped the cellphone, grabbed the steering wheel with her left hand, and steered the car into a parking lot. Then she used her left foot to pry her right foot off the accelerator. She pulled down the visor to look in the mirror. The right side of her face was paralyzed. With great difficulty, Dr. Fite twisted her body and grasped her cellphone. Copyright 2007 The New York Times Company

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 10339 - Posted: 06.24.2010

By MARIA CHENG, BARCELONA, Spain – An experimental drug reduces the stroke risk in patients with irregular heartbeats by nearly four times, compared with the popular drug warfarin — but possibly at a cost, according to new research released Sunday. Patients taking the new drug dabigatran etexilate, made by German pharmaceutical Boehringer Ingelheim, also were slightly more likely to have heart attacks or stomach pain, according to the research presented at the European Society of Cardiology meeting in Barcelona. Patients with irregular heartbeats are up to 17 times more likely to have a stroke than healthy people. About one-sixth of all strokes occur in patients with irregular heartbeats who also have other risk factors such as smoking or obesity. In the United States, there are about 2 million people with such a condition. Until now most such patients have been given warfarin, which has been around since the 1950s and has side effects including bleeding risks and requires lifestyle changes such as dietary restrictions. Doctors hope the new drug can help improve treatment for patients, who must be monitored continuously if they are put on warfarin and avoid alcohol and foods such as spinach and cranberries. © 2009 The Associated Press.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 13224 - Posted: 06.24.2010

By Katherine Harmon In the months after he had surgery to fix his defective heart valve, Bruce Stutz didn't feel quite the same. It wasn't his physical fitness that was subpar, although that did require some post-op retraining, but rather his mental capacity. "I couldn't muster the concentration to deal with the problem," he wrote in a 2003 article for Scientific American. During surgery, Stutz had been hooked up to a heart–lung machine, also called a cardiopulmonary-bypass pump, for the two-hours of a procedure to keep his blood oxygenated and flowing while his heart was stopped. He found that he was not the only one who, after time on the pump, had felt their brains bogged down by simple tasks. A 2001 study in The New England Journal of Medicine found that of 261 heart disease patients who had been kept alive during surgery with the pump, 42 percent showed cognitive decline five years after the surgery, even after adjusting for age. "Interventions to prevent or reduce short- and long-term cognitive decline after cardiac surgery are warranted," the authors, led by Mark Newman of the Duke University Medical Center, concluded. And a study published earlier this year in The Annals of Thoracic Surgery, led by James Slater, a cardiothoracic surgeon at the Mid-Atlantic Surgical Associates in Morristown, N.J., supported the previous findings, showing that lowered levels of oxygen in blood flowing to the brain during surgery did correlate to increased risk of suffering from the mental impairment dubbed "pump head". © 1996-2009 Scientific American Inc.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 13137 - Posted: 06.24.2010

Colin Barras Nine years ago, a brain-stem stroke left Erik Ramsey almost totally paralysed, but with his mental faculties otherwise intact. Today he is learning to talk again – although so far he can only manage basic vowel sounds. In 2004, Ramsey had an electrode implanted in his speech-motor cortex by Philip Kennedy's team at Neural Signals, a company based in Duluth, Georgia, US, who hoped the signal from Ramsey's cortex could be used to restore his speech. Interpreting these signals proved tricky, however. Fortunately, another team headed by Frank Guenther at Boston University, Massachusetts, US, has been working on the same problem from the opposite direction. Guenther and his colleagues have used information from brain scans of healthy patients to monitor neural activity during speech. These studies show that the brain signals don't code for words, but instead control the position of the lips, tongue, jaw and larynx to produce basic sounds. Guenther's research group then developed software that could recognise and translate the patterns of brain activity during speech. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 11799 - Posted: 06.24.2010

Amid the dazzling high-tech displays of new-generation brain-machine interfaces (including brain implants with which monkeys can operate robotic arms) was a less glamorous but elegantly simple study which promises to improve quality of life for stroke victims, or victims of traumatic brain injury, whose ability to balance has been obliterated. Monica Metea of the company Wicab in Wisconsin displayed her company’s new balancing device BrainPort which has been through a pilot study of 17 patients, allowing them to stand, walk, dance without falling over. It works on the principle of brain plasticity. It’s a slim 2 cm square grid of 100 electrodes connected to a head position-detecting sensor which sits directly above them. The patients sticks the device in their mouths, and quickly learns from the pattern of the pinprick sensations delivered by the electrodes which way is up and which way is down. The brain also learns this in a physical sense. Somehow certain circuits get reconfigured such that even after the device is removed – after 20 minutes or so – the patient maintains his or her sense of balance, for hours, sometimes for days. No need to open up the skull and implant the device directly into delicate brain tissue like the more dramatic stories which will eventually help the paralysed. But applicable to probably millions of people who can’t stand up without falling over.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 10946 - Posted: 06.24.2010