Chapter 19. Language and Hemispheric Asymmetry
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Scientists and clinicians have long dreamed of helping the injured brain repair itself by creating new neurons, and an innovative NIH-funded study published today in Nature Medicine may bring this goal much closer to reality. A team of researchers has developed a therapeutic technique that dramatically increases the production of nerve cells in mice with stroke-induced brain damage. The therapy relies on the combination of two methods that show promise as treatments for stroke-induced neurological injury. The first consists of surgically grafting human neural stem cells into the damaged area, where they mature into neurons and other brain cells. The second involves administering a compound called 3K3A-APC, which the scientists have shown helps neural stem cells grown in a petri dish develop into neurons. However, it was unclear what effect the molecule, derived from a human protein called activated protein-C (APC), would have in live animals. A month after their strokes, mice that had received both the stem cells and 3K3A-APC performed significantly better on tests of motor and sensory functions compared to mice that received neither or only one of the treatments. In addition, many more of the stem cells survived and matured into neurons in the mice given 3K3A-APC. “This USC-led animal study could pave the way for a potential breakthrough in how we treat people who have experienced a stroke,” added Jim Koenig, Ph.D., a program director at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS), which funded the research. “If the therapy works in humans, it could markedly accelerate the recovery of these patients.”
By Daniel Barron After prepping for the day’s cases, “Mike Brennan,” a 63-year-old cardiology technician, sat down for his morning coffee and paper. On the front page, he discovered something troubling: he could no longer read. No matter how long he stared at a word, its meaning was lost on him. With a history of smoking and hypertension, he worried that he might have had a stroke. So, leaving his coffee, he walked himself down the hall to the emergency department, where neurologists performed a battery of tests to tease out what had happened. Mike still recognized individual letters and, with great difficulty, could sound out small words. But even some simple vocabulary presented problems, for example, he read “desk” as “dish” or “flame” as “thame.” Function words such as prepositions and pronouns gave him particular trouble. Mike couldn’t read, but there was nothing wrong with his eyes. Words heard were no problem. He could recognize colors, faces, and objects. He could speak, move, think and even write normally. Mike had “pure alexia,” meaning he could not read but showed no other impairments. An M.R.I. scan of Mike’s brain revealed a pea-sized stroke in his left inferior occipitotemporal cortex, a region on the brain’s surface just behind the left ear. © 2016 Scientific American
Link ID: 22586 - Posted: 08.23.2016
By Roni Caryn Rabin Dementia is a general term for a set of symptoms that includes severe memory loss, a significant decline in reasoning and severely impaired communication skills; it most commonly strikes elderly people and used to be referred to as “senility.” Alzheimer’s disease is a specific illness that is the most common cause of dementia. Though many diseases can cause dementia, Alzheimer’s accounts for 60 percent to 80 percent of dementia cases, “which is why you’ll often hear the terms used interchangeably,” said Heather Snyder, the senior director of medical and scientific operations for the Alzheimer’s Association. She said the question comes up frequently because patients may receive an initial diagnosis of dementia followed by an evaluation that yields the more specific diagnosis of Alzheimer’s disease, and they may be confused. The second most common form of dementia is vascular dementia, which is caused by a stroke or poor blood flow to the brain. Other diseases that can lead to dementia include Huntington’s disease, Parkinson’s disease and Creutzfeldt-Jakob disease. Some patients may have more than one form of dementia. Dementia is caused by damage to brain cells. In the case of Alzheimer’s disease, that damage is characterized by telltale protein fragments or plaques that accumulate in the space between nerve cells and twisted tangles of another protein that build up inside cells. In Alzheimer’s disease, dementia gets progressively worse to the point where patients cannot carry out daily activities and cannot speak, respond to their environment, swallow or walk. Although some treatments may temporarily ease symptoms, the downward progression of disease continues and it is not curable. © 2016 The New York Times Company
Link ID: 22559 - Posted: 08.16.2016
By NICHOLAS ST. FLEUR Orangutan hear, orangutan do. Researchers at the Indianapolis Zoo observed an orangutan mimic the pitch and tone of human sounds, for the first time. The finding, which was published Wednesday, provides insight into the evolutionary origin of human speech, the team said. “It really redefines for us what we know about the capabilities of orangutans,” said Rob Shumaker, director of the zoo and an author on the paper. “What we have to consider now is the possibility that the origins of spoken language are not exclusively human, and that they may have come from great apes.” Rocky, an 11-year-old orangutan at the zoo, has a special ability. He can make sounds using his vocal folds, or voice box, that resemble the vowel “A,” and sound like “Ah.” The noises, or “wookies” as the researchers called them, are variations of the same vocalization. Sometimes the great ape would say high-pitched “wookies” and sometimes he would say his “Ahs” in a lower pitch. The researchers note that the sounds are specific to Rocky and ones that he used everyday. No other orangutan, captive or wild, made these noises. Rocky, who had never lived in the rain forest, apparently learned the skill during his time as an entertainment orangutan before coming to the zoo. He was at one point the most seen orangutan in movies and commercials, according to the zoo. The researchers said that Rocky’s grunts show that great apes have the capacity to learn to control their muscles to deliberately alter their sounds in a “conversational” manner. The findings, which were published in the journal Scientific Reports, challenge the notion that orangutans — an endangered species that shares about 97 percent of it DNA with humans — make noises simply in response to something, sort of like how you might scream when you place your hand on a hot stove. © 2016 The New York Times Company
Laura Sanders Under duress, nerve cells get a little help from their friends. Brain cells called astrocytes send their own energy-producing mitochondria to struggling nerve cells. Those gifts may help the neurons rebound after injuries such as strokes, scientists propose in the July 28 Nature. It was known that astrocytes — star-shaped glial cells that, among other jobs, support neurons — take in and dispose of neurons’ discarded mitochondria. Now it turns out that mitochondria can move the other way, too. This astrocyte-to-neuron transfer is surprising, says neuroscientist Jarek Aronowski of the University of Texas Health Science Center at Houston. “Bottom line: It’s sort of shocking.” Study coauthor Eng Lo of Massachusetts General Hospital and Harvard Medical School cautions that the work is at a very early stage. But he hopes that a deeper understanding of this process might ultimately point out new ways to protect the brain from damage. Mitochondria produce the energy that powers cells in the body. Scientists have spotted the organelles moving into damaged cells in other parts of the body, including the lungs, heart and liver. The new study turns up signs of this mitochondrial generosity in the brain. Astrocytes produce mitochondria and shunt them out into the soup that surrounds cells, Lo and colleagues found. The researchers then put neurons into this mitochondria-rich broth. When starved of glucose and oxygen — a situation that approximates a stroke — the neurons took in the astrocyte-made organelles. |© Society for Science & the Public 2000 - 2016
By Emily Underwood If your car’s battery dies, you might call on roadside assistance—or a benevolent bystander—for a jump. When damaged neurons lose their “batteries,” energy-generating mitochondria, they call on a different class of brain cells, astrocytes, for a boost, a new study suggests. These cells respond by donating extra mitochondria to the floundering neurons. The finding, still preliminary, might lead to novel ways to help people recover from stroke or other brain injuries, scientists say. “This is a very interesting and important study because it describes a new mechanism whereby astrocytes may protect neurons,” says Reuven Stein, a neurobiologist at The Rabin Institute of Neurobiology in Tel Aviv, Israel, who was not involved in the study. To keep up with the energy-intensive work of transmitting information throughout the brain, neurons need a lot of mitochondria, the power plants that produce the molecular fuel—ATP—that keeps cells alive and working. Mitochondria must be replaced often in neurons, in a process of self-replication called fission—the organelles were originally microbes captured inside a cell as part of a symbiosis. But if mitochondria are damaged or if they can’t keep up with a cell’s needs, energy supplies can run out, killing the cell. In 2014, researchers published the first evidence that cells can transfer mitochondria in the brain—but it seemed more a matter of throwing out the trash. When neurons expel damaged mitochondria, astrocytes swallow them and break them down. Eng Lo and Kazuhide Hayakawa, both neuroscientsists at Massachusetts General Hospital in Charlestown, wondered whether the transfer could go the other way as well—perhaps astrocytes donated working mitochondria to neurons in distress. Research by other groups supported that idea: A 2012 study, for example, found that stem cells from bone marrow can donate mitochondria to lung cells after severe injury. © 2016 American Association for the Advancement of Science
An orangutan copying sounds made by researchers offers new clues to how human speech evolved, scientists say. Rocky mimicked more than 500 vowel-like noises, suggesting an ability to control his voice and make new sounds. It had been thought these great apes were unable to do this and, since human speech is a learned behaviour, it could not have originated from them. Study lead Dr Adriano Lameira said this "notion" could now be thrown "into the trash can". Dr Lameira, who conducted the research at Amsterdam University prior to joining Durham University, said Rocky's responses had been "extremely accurate". The team wanted to make sure the ape produced a new call, rather than adapting a "normal orangutan call with a personal twist" or matching sounds randomly or by coincidence, he said. The new evidence sets the "start line for scientific inquiry at a higher level", he said. "Ultimately, we should be now in a better position to think of how the different pieces of the puzzle of speech evolution fit together." The calls Rocky made were different from those collected in a large database of recordings, showing he was able to learn and produce new sounds rather than just match those already in his "vocabulary". In a previous study Dr Lameira found a female orangutan at Cologne Zoo in Germany was able to make sounds with a similar pace and rhythm to human speech. Researchers were "astounded" by Tilda's vocal skills but could not prove they had been learned, he said. However, the fact that "other orangutans seem to be exhibiting equivalent vocal skills shows that Rocky is not a bizarre or abnormal individual", Dr Lameira said. © 2016 BBC.
By Tim Page When I returned to California, I brought my diaries into the back yard every afternoon and read them through sequentially, with the hope of learning more about the years before my brain injury. I remembered much of what I’d done professionally, and whatever additional information I needed could usually be found on my constantly vandalized Wikipedia page. Here was the story of an awkward, imperious child prodigy who made his own films and became famous much too early; a music explainer who won a Pulitzer Prize; a driven and obsessive loner whose fascinations led to collaborations with Glenn Gould, Philip Glass and Thomas Pynchon. In 2000, at age 45, I was diagnosed with Asperger’s syndrome. In retrospect, the only surprise is that it took so long. But the diaries offered a more intimate view. Reading them was slow going, and I felt as though my nose was pressed up against the windowpane of my own life. The shaggy-dog accretion of material — phone numbers, long-ago concert dates, coded references to secret loves — all seemed to belong to somebody else. My last clear memory was of a muggy, quiet Sunday morning in July, three months earlier, as I waited for a train in New London, Conn. It was 11:13 a.m., and the train was due to arrive two minutes later. I was contented, proud of my punctuality and expecting an easy ride to New York in the designated “quiet car,” with just enough time to finish whatever book I was carrying. There would be dinner in Midtown with a magical friend, followed by overnight family visits in Baltimore and Washington, and then a flight back to Los Angeles and the University of Southern California, at which point a sabbatical semester would be at an end.
By Ann Grisold, Oscar, 6, sits at the family dinner table and endures the loneliest hour of his day. The room bustles with activity: Oscar’s sister passes plates and doles out broccoli florets. His father and uncle exchange playful banter. Oscar’s mother emerges from the kitchen carrying a platter of carved meat; a cousin pulls up an empty chair. “Chi fan le!” shouts Oscar’s older sister, in Mandarin Chinese. Time for dinner! “Hao,” her grandfather responds from the other room. Okay. Family members tell stories and rehash the day, all in animated Chinese. But when they turn to Oscar, who has autism, they speak in English. “Eat rice,” Oscar’s father says. “Sit nice.” Except there is no rice on the table. In Chinese, ‘eat rice’ can refer to any meal, but its meaning is lost in translation. Pediatricians, educators and speech therapists have long advised multilingual families to speak one language — the predominant one where they live — to children with autism or other developmental delays. The reasoning is simple: These children often struggle to learn language, so they’re better off focusing on a single one. However, there are no data to support this notion. In fact, a handful of studies show that children with autism can learn two languages as well as they learn one, and might even thrive in multilingual environments. Lost in translation: It’s not just children with autism who miss out when parents speak only English at home — their families, too, may experience frustrating miscommunications. Important instructions, offhand remarks and words of affection are often lost in translation when families swap their heritage language for English, says Betty Yu, associate professor of special education and communicative disorders at San Francisco State University. © 2016 Scientific American,
By Sara Chodosh There has long been debate about a link between serious blows to the head and the development of neurodegenerative diseases later in life. Research has made cases for and against a relationship between traumatic brain injuries and neurological ailments such as Alzheimer’s, Parkinson’s and general dementia. Now the question is drawing ever more scrutiny as the alarming extent of these injuries becomes better known—and new research is finally casting some light on this murky and often quietly terrifying topic. A large-scale analysis of three separate studies published this week in JAMA Neurology found no association between unconsciousness-causing traumatic brain injuries (TBI) and Alzheimer’s disease or general dementia—but it did find a strong association between TBI and Parkinson’s disease. “I can’t decide if the positive or negative findings are more surprising,” says one of the study’s investigators, physician and Alzheimer’s researcher Paul Crane at the University of Washington. The positive association his team found between Parkinson’s and TBI was not entirely novel, but Crane says the magnitude of the link was unexpected. The researchers found the risk of Parkinson’s rose threefold for people whose head injuries had caused them to go unconscious for more than an hour. The more contentious finding is the lack of an association between TBI and Alzheimer’s. Prior research has been divided on whether there is a link, but many of the previous studies have been smaller in scale and conducted less-comprehensive analyses. “Although early studies suggested a clear link between TBI and an increased risk for Alzheimer’s disease, this has not been replicated,” explains Frances Corrigan at the University of Adelaide, who studies how TBI influences neurodegeneration. © 2016 Scientific American,
Rachel Ehrenberg When mice have a stroke, their gut reaction can amp up brain damage. A series of new experiments reveals a surprising back-and-forth between the brain and the gut in the aftermath of a stroke. In mice, this dickering includes changes to the gut microbial population that ultimately lead to even more inflammation in the brain. There is much work to be done to determine whether the results apply to humans. But the research, published in the July 13 Journal of Neuroscience, hints that poop pills laden with healthy microbes could one day be part of post-stroke therapy. The work also highlights a connection between gut microbes and brain function that scientists are only just beginning to understand,says Ted Dinan of the Microbiome Institute at the University College Cork, Ireland. There’s growing evidence that gut microbes can influence how people experience stress or depression, for example (SN: 4/2/16, p. 23). “It’s a fascinating study” says Dinan, who was not involved with the work. “It raises almost as many questions as it answers, which is what good studies do.” Following a stroke, the mouse gut becomes temporarily paralyzed, leading to a shift in the microbial community, neurologist Arthur Liesz of the Institute for Stroke and Dementia Research in Munich and colleagues found. This altered, less diverse microbial ecosystem appears to interact with immune system cells called T cells that reside in the gut. These T cells can either dampen inflammation or dial it up, leading to more damage, says Liesz. Whether the T cells further damage the brain after a stroke rather than soothe it seems to be determined by the immune system cells’ interaction with the gut microbes. © Society for Science & the Public 2000 - 2016.
Link ID: 22431 - Posted: 07.13.2016
DAVID GREENE, HOST: Nearly one-quarter of all Americans reach for a bottle of acetaminophen every single week. Many of you might know this drug as Tylenol. It's a pain killer that can take the edge off a headache or treat you when you have a fever. It also might have another effect. And let's talk about this with NPR social science correspondent Shankar Vedantam. And, Shankar, straight out, is this going to make me not want to take Tylenol, what you're about to tell me? VEDANTAM: It might make you not want to take Tylenol when you're talking with me, David. GREENE: Oh, even more interesting. VEDANTAM: (Laughter) I was speaking with Dominik Mischkowski. He's currently a researcher at the National Institutes of Health. He recently conducted a couple of double blind experiments. These are experiments where the volunteers are given either sugar pills or Tylenol, but neither the volunteers nor the researchers know which volunteers are getting which pill. Mischkowski and his advisers at Ohio State University, Jennifer Crocker and Baldwin Way, they played loud noises for the volunteers. Not surprisingly, volunteers given Tylenol experienced less physical discomfort than volunteers given the placebo. © 2016 npr
Keyword: Pain & Touch
Link ID: 22403 - Posted: 07.07.2016
By Anthea Rowan The neurologist does not cushion his words. He tells us how it is: “She won’t read again.” I am standing behind my mother. I feel her stiffen. We do not talk of this revelation for days — and when we do, we do it in the garden of the rehab facility where she is recovering from a stroke. The stroke has scattered her memory, but she has not forgotten she will apparently not read again. I was shocked by what the doctor said, she confides. Me, too. Do you believe him? she asks. No — I am emphatic, for her and for me — I don’t. Mum smiles: “Me neither.” The damage wreaked by Mum’s stroke leaked across her brain, set up roadblocks so that the cerebral circuit board fizzes and pops uselessly, with messages no longer neatly passing from “A” to “B.” I tell the neuro: “I thought they’d learn to go via ‘D’ or ‘W.’ Isn’t that what’s supposed to happen — messages reroute?” “Unlikely,” he responds. “In your mother’s case.” Alexia — the loss of the ability to read — is common after strokes, especially, as in my mother’s case, when damage is wrought in the brain’s occipital lobe, which processes visual information. Pure alexia, which is Mum’s diagnosis, is much more rare: She can still write and touch-type, but bizarrely, she cannot read.
Playing simple card games, such as snap, can help stroke patients with their recovery, say Canadian researchers. The scientists found it improved patients' motor skills. Playing Jenga, bingo or a games consol like Wii worked equally well. They told the Lancet Neurology that the type of task used for motor rehabilitation might be less relevant, as long as it is intensive, repetitive and gets the hands and arms moving. The researchers designed their study to test whether virtual reality gaming, which is increasingly being employed as a rehab therapy for stroke patients, is any better than more traditional games for honing upper limb motor skills. The Canadian team recruited 141 patients who had recently suffered a stroke, and now had some impaired movement in one or both of their hands and arms. Approximately half of the patients, at random, were then allocated to the Wii rehab, while the rest were asked to do other recreational activities, such as playing cards. All of the patients continued to receive usual stroke rehabilitation care and support on top of the 10, one-hour sessions of gaming or card playing for a fortnight. Both groups showed significant improvement in their motor skills at the end of the two weeks and four weeks later. Importantly, both groups fared equally well, say the researchers. While it's not clear from this study how much of the improvement was from the regular stroke care the participants received, other research suggests adding in more therapy is beneficial. Investigator Dr Gustavo Saposnik, from St Michael's Hospital in Toronto, said: "We all like technology and have the tendency to think that new technology is better than old-fashioned strategies, but sometimes that's not the case. In this study, we found that simple recreational activities that can be implemented anywhere may be as effective as technology." © 2016 BBC.
Link ID: 22367 - Posted: 06.28.2016
by Helen Thompson Young zebra finches (Taeniopygia guttata) learn to sing from a teacher, usually dad. Remembering dad’s tunes may even be hardwired into the birds’ brains. Researchers at the Okinawa Institute of Science and Technology in Japan measured activity in the brains of male juvenile birds listening to recordings of singing adult males, including their fathers. The team focused its efforts on neurons in a part of the brain called the caudomedial nidopallium that’s thought to influence song learning and memory. A subset of neurons in the caudomedial nidopallium lit up in response to songs performed by dad but not those of strangers, the team reports June 21 in Nature Communications. The more baby birds heard songs, the more their neurons responded and the clearer their own songs became. Sleep and a neurotransmitter called GABA influenced this selectivity. The researchers suggest that this particular region of the brain stores song memories as finches learn to sing, and GABA may drive the storage of dad’s songs over others. Researchers played a variety of sounds for young zebra finches: their own song, dad’s song and songs and calls from other adult finches. Over time, their songs became more and more similar to that of their father. |© Society for Science & the Public 2000 - 2016
In a study of stroke patients, investigators confirmed through MRI brain scans that there was an association between the extent of disruption to the brain’s protective blood-brain barrier and the severity of bleeding following invasive stroke therapy. The results of the National Institutes of Health-funded study were published in Neurology. These findings are part of the Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution (DEFUSE)-2 Study, which was designed to see how MRIs can help determine which patients undergo endovascular therapy following ischemic stroke caused by a clot blocking blood flow to the brain. Endovascular treatment targets the ischemic clot itself, either removing it or breaking it up with a stent. The blood-brain barrier is a layer of cells that protects the brain from harmful molecules passing through the bloodstream. After stroke, the barrier is disrupted, becoming permeable and losing control over what gets into the brain. “The biggest impact of this research is that information from MRI scans routinely collected at a number of research hospitals and stroke centers can inform treating physicians on the risk of bleeding,” said Richard Leigh, M.D., a scientist at NIH’s National Institute of Neurological Disorders and Stroke (NINDS) and an author on the study. In this study, brain scans were collected from more than 100 patients before they underwent endovascular therapy, within 12 hours of stroke onset. Dr. Leigh and his team obtained the images from DEFUSE-2 investigators.
by Laura Sanders Any parent trying to hustle a school-bound kid out the door in the morning knows that her child’s skull possesses a strange and powerful form of black magic: It can repel parents’ voices. Important messages like “find your shoes” bounce off the impenetrable fortress and drift unheeded to the floor. But when this perplexing force field is off, it turns out that mothers’ voices actually have profound effects on kids. Children’s brains practically buzz when they hear their moms’ voices, scientists report in the May 31 Proceedings of the National Academy of Sciences. (Fun and not surprising side note: Babies’ voices get into moms’ brains, too.) The parts of kids’ brains that handle emotions, face recognition and reward were prodded into action by mothers’ voices, brain scans of 24 children ages 7 to 12 revealed. And words were not required to get this big reaction. In the study, children listened to nonsense words said by either their mother or one of two unfamiliar women. Even when the words were fake, mothers’ voices still prompted lots of neural action. The study was done in older kids, but children are known to tune into their mothers’ voices early. Really early, in fact. One study found that fetuses’ heart rates change when they hear their moms read a story. For a fetus crammed into a dark, muffled cabin, voices may take on outsized importance. |© Society for Science & the Public 2000 - 2016.
By Amina Zafar, When Susan Robertson's fingers and left arm felt funny while she was Christmas shopping, they were signs of a stroke she experienced at age 36. The stroke survivor is now concerned about her increased risk of dementia. The link between stroke and dementia is stronger than many Canadians realize, the Heart and Stroke Foundation says. The group's annual report, released Thursday, is titled "Mind the connection: preventing stroke and dementia." Stroke happens when blood stops flowing to parts of the brain. Robertson, 41, of Windsor, Ont., said her short-term memory, word-finding and organizational skills were impaired after her 2011 stroke. She's extremely grateful to have recovered the ability to speak and walk after doctors found clots had damaged her brain's left parietal lobe. "I knew what was happening, but I couldn't say it," the occupational nurse recalled. Dementia risk A stroke more than doubles the risk of dementia, said Dr. Rick Swartz, a spokesman for the foundation and a stroke neurologist in Toronto. Raising awareness about the link is not to scare people, but to show how controlling blood pressure, not smoking or quitting if you do, eating a balanced diet and being physically active reduce the risk to individuals and could make a difference at a society level, Swartz said. While aging is a common risk factor in stroke and dementia, evidence in Canada and other developed countries shows younger people are also increasingly affected. ©2016 CBC/Radio-Canada.
By Karin Brulliard Think about how most people talk to babies: Slowly, simply, repetitively, and with an exaggerated tone. It’s one way children learn the uses and meanings of language. Now scientists have found that some adult birds do that when singing to chicks — and it helps the baby birds better learn their song. The subjects of the new study, published last week in the journal Proceedings of the National Academy of Sciences, were zebra finches. They’re good for this because they breed well in a lab environment, and “they’re just really great singers. They sing all the time,” said McGill University biologist and co-author Jon Sakata. The males, he means — they’re the singers, and they do it for fun and when courting ladies, as well as around baby birds. Never mind that their melody is more “tinny,” according to Sakata, than pretty. Birds in general are helpful for vocal acquisition studies because they, like humans, are among the few species that actually have to learn how to make their sounds, Sakata said. Cats, for example, are born knowing how to meow. But just as people pick up speech and bats learn their calls, birds also have to figure out how to sing their special songs. Sakata and his colleagues were interested in how social interactions between adult zebra finches and chicks influences that learning process. Is face-to-face — or, as it may be, beak-to-beak — learning better? Does simply hearing an adult sing work as well as watching it do so? Do daydreaming baby birds learn as well as their more focused peers? © 1996-2016 The Washington Post
By Andy Coghlan People once dependent on wheelchairs after having a stroke are walking again since receiving injections of stem cells into their brains. Participants in the small trial also saw improvements in their speech and arm movements. “One 71-year-old woman could only move her left thumb at the start of the trial,” says Gary Steinberg, a neurosurgeon at Stanford University who performed the procedure on some of the 18 participants. “She can now walk and lift her arm above her head.” Run by SanBio of Mountain View, California, this trial is the second to test whether stem cell injections into patients’ brains can help ease disabilities resulting from stroke. Patients in the first, carried out by UK company ReNeuron, also showed measurable reductions in disability a year after receiving their injections and beyond. All patients in the latest trial showed improvements. Their scores on a 100-point scale for evaluating mobility – with 100 being completely mobile – improved on average by 11.4 points, a margin considered to be clinically meaningful for patients. “The most dramatic improvements were in strength, coordination, ability to walk, the ability to use hands and the ability to communicate, especially in those whose speech had been damaged by the stroke,” says Steinberg. In both trials, improvements in patients’ mobility had plateaued since having had strokes between six months and three years previously. © Copyright Reed Business Information Ltd