Chapter 15. Brain Asymmetry, Spatial Cognition, and Language

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By Jennifer Couzin-Frankel Athena Akrami’s neuroscience lab reopened last month without her. Life for the 38-year-old is a pale shadow of what it was before 17 March, the day she first experienced symptoms of the novel coronavirus. At University College London (UCL), Akrami’s students probe how the brain organizes memories to support learning, but at home, she struggles to think clearly and battles joint and muscle pain. “I used to go to the gym three times a week,” Akrami says. Now, “My physical activity is bed to couch, maybe couch to kitchen.” Her early symptoms were textbook for COVID-19: a fever and cough, followed by shortness of breath, chest pain, and extreme fatigue. For weeks, she struggled to heal at home. But rather than ebb with time, Akrami’s symptoms waxed and waned without ever going away. She’s had just 3 weeks since March when her body temperature was normal. “Everybody talks about a binary situation, you either get it mild and recover quickly, or you get really sick and wind up in the ICU,” says Akrami, who falls into neither category. Thousands echo her story in online COVID-19 support groups. Outpatient clinics for survivors are springing up, and some are already overburdened. Akrami has been waiting more than 4 weeks to be seen at one of them, despite a referral from her general practitioner. The list of lingering maladies from COVID-19 is longer and more varied than most doctors could have imagined. Ongoing problems include fatigue, a racing heartbeat, shortness of breath, achy joints, foggy thinking, a persistent loss of sense of smell, and damage to the heart, lungs, kidneys, and brain. © 2020 American Association for the Advancement of Science.

Keyword: Stroke; Stress
Link ID: 27399 - Posted: 08.03.2020

By Joshua Sokol A beast calls in the distance. Hearing a low rumble, you might imagine the source will be an unholy cross between a wild boar and a chain saw. The message is unmistakable: I’m here, I’m huge and you can either come mate with me or stay out of my way. Surprise! It’s just a cuddly little koala. Like online dating, the soundscape of the animal world is rife with exaggerations about size, which animals use to scare off rivals and attract mates. Gazelles, howler monkeys, bats and many more creatures have evolved to create calls with deep sonic frequencies that sound as if they come from a much larger animal. Now scientists have proposed this same underlying pressure to exaggerate size might be linked to an even deeper mystery. It could have spurred mammals toward developing the ability to make a wider array of possible calls, to mimic sounds after hearing them and maybe even speech, what scientists call vocal learning. “We are offering one possible way for vocal learning to have evolved,” says Maxime Garcia, a biologist at the University of Zurich in Switzerland who suggested the relationship with his colleague, Andrea Ravignani, in the journal Biology Letters this month. Their idea builds off previous studies on vocal learning in humans. Beyond just opera singers, beatboxers and Michael Winslow from the “Police Academy” movies, we all have some level of control over the frequencies of our voices. “I can tell you to lower your pitch or try to sound big, and you can soound like thissss,” said Katarzyna Pisanski at the University of Lyon in France, affecting a deep voice. © 2020 The New York Times Company

Keyword: Animal Communication; Sexual Behavior
Link ID: 27393 - Posted: 07.31.2020

Masakazu (Mark) Konishi, the Bing Professor of Behavioral Biology, Emeritus, passed away on July 23. He was 87 years old. Renowned for his work on the neuroscience underlying the behavior of owls and songbirds, Konishi joined the Caltech faculty as a professor of biology in 1975, becoming the Bing Professor of Behavioral Biology in 1980. Since the early 1960s, Konishi was a leader in the field of avian neuroethology—the neurobiological study of natural behavior, such as prey capture by owls and singing in songbirds. In his laboratory at Caltech, Konishi advised dozens of graduate students and postdoctoral scholars. His team worked extensively on the auditory systems of barn owls, which use their acute hearing to home in on prey on the ground, even in total darkness. Konishi was the first to theorize that young birds initially remember a tutor song and use the memory as a template to guide the development of their own song. Konishi was born in Kyoto, Japan, on February 17, 1933. He attended Hokkaido University in Sapporo, Japan, for his bachelor and master of science degrees, after which he attended the UC Berkeley for his PhD. Under Berkeley professor Peter Marler, Konishi focused his doctoral research on the idea of central coordination. Konishi began a full professorship at Caltech in 1975. He was the Bing Professor of Behavioral Biology until his retirement in 2013. From 1977 to 1980, Konishi served as the division's executive officer for biology.

Keyword: Animal Communication; Language
Link ID: 27383 - Posted: 07.27.2020

Ian Sample Science editor Doctors may be missing signs of serious and potentially fatal brain disorders triggered by coronavirus, as they emerge in mildly affected or recovering patients, scientists have warned. Neurologists are on Wednesday publishing details of more than 40 UK Covid-19 patients whose complications ranged from brain inflammation and delirium to nerve damage and stroke. In some cases, the neurological problem was the patient’s first and main symptom. The cases, published in the journal Brain, revealed a rise in a life-threatening condition called acute disseminated encephalomyelitis (Adem), as the first wave of infections swept through Britain. At UCL’s Institute of Neurology, Adem cases rose from one a month before the pandemic to two or three per week in April and May. One woman, who was 59, died of the complication. A dozen patients had inflammation of the central nervous system, 10 had brain disease with delirium or psychosis, eight had strokes and a further eight had peripheral nerve problems, mostly diagnosed as Guillain-Barré syndrome, an immune reaction that attacks the nerves and causes paralysis. It is fatal in 5% of cases. “We’re seeing things in the way Covid-19 affects the brain that we haven’t seen before with other viruses,” said Michael Zandi, a senior author on the study and a consultant at the institute and University College London Hospitals NHS foundation trust. “What we’ve seen with some of these Adem patients, and in other patients, is you can have severe neurology, you can be quite sick, but actually have trivial lung disease,” he added. “Biologically, Adem has some similarities with multiple sclerosis, but it is more severe and usually happens as a one-off. Some patients are left with long-term disability, others can make a good recovery.” © 2020 Guardian News & Media Limited

Keyword: Stroke; Movement Disorders
Link ID: 27354 - Posted: 07.08.2020

By Linda Searing Every 40 seconds, on average, someone in the United States has a stroke — amounting to 795,000 people a year, according to the Centers for Disease Control and Prevention. Most strokes, 80 percent or more, occur when blood flow to the brain is blocked by a clot. Known as an ischemic stroke, it results in brain cells not getting needed oxygen and nutrients, which causes the cells to start dying within minutes. The other main type of stroke, hemorrhagic stroke, occurs when a blood vessel in the brain leaks or bursts, with the flood of blood putting pressure on and damaging the brain cells. This type of stroke may be caused by high blood pressure (which over time can weaken blood vessel walls) or an aneurysm (a bulge in a blood vessel that bursts). Both types of stroke can cause lasting brain damage, disability or death, and some 140,000 Americans die each year from a stroke. The likelihood of brain damage and disability increases the longer a stroke goes untreated, making it critical to call 911 and get emergency stroke treatment started as soon as possible. Signs of a stroke usually come on suddenly and may include numbness or weakness in the face, arm or leg, trouble speaking, blurred or double vision, dizziness or stumbling when trying to walk or a very severe headache. A condition similar to a stroke, known as a transient ischemic attack, occurs when the blood supply to the brain is blocked for a short time (hence its nickname, “mini-stroke”). Though damage to the brain from a TIA is not permanent, it does make the chances of a full-blown stroke more likely. Because of this, the American Stroke Association refers to a TIA as a “warning stroke.” © 1996-2020 The Washington Post

Keyword: Stroke
Link ID: 27347 - Posted: 07.08.2020

By Cara Giaimo Even if you’re not a bird person, you probably know the jaunty song of the white-throated sparrow. It plays on loop in North America’s boreal forests, a classic as familiar as the chickadee’s trill and the mourning dove’s dirge. It even has its own mnemonic, “Old Sam Peabody-Peabody-Peabody.” But over the past half-century, the song’s hook — its triplet ending — has changed, replaced by a new, doublet-ended variant, according to a paper published Thursday in Current Biology. It seems the sparrows want to sing something new. The study, which took 20 years, is “the first to track the cultural evolution of birdsong at the continental scale,” said Mason Youngblood, a doctoral candidate in animal behavior at the CUNY Graduate Center who was not involved in the research. It describes a much broader and more rapid shift in birdsong than was previously thought to occur. Scott Ramsay, a behavioral ecologist at Wilfrid Laurier University in Ontario, was the first to notice that the forest sounded a little off during a visit to western Canada with Ken Otter, a professor at the University of Northern British Columbia. “He said, ‘Your birds are singing something weird,’” Dr. Otter recalled. Dr. Otter recorded some white-throated sparrow songs and turned them into spectrograms — visualizations that lay birdsongs out, so they can be more easily compared. The classic “Old Sam Peabody-Peabody-Peabody” songs ended in a triplet pattern: repeated sets of three notes. The new songs ended in doublets, like the record got stuck: “Old Sam Peabuh-Peabuh-Peabuh-Peabuh.” It was “a different kind of syncopation pattern,” Dr. Otter said. “They were kind of stuttering it.” Like many birds, male white-throated sparrows use songs to signal where their territory is, and to attract mates. Each individual sparrow has his own way of starting the song, but they all converge on a shared ending. © 2020 The New York Times Company

Keyword: Animal Communication; Language
Link ID: 27346 - Posted: 07.06.2020

By Bruce Bower An aptitude for mentally stringing together related items, often cited as a hallmark of human language, may have deep roots in primate evolution, a new study suggests. In lab experiments, monkeys demonstrated an ability akin to embedding phrases within other phrases, scientists report June 26 in Science Advances. Many linguists regard this skill, known as recursion, as fundamental to grammar (SN: 12/4/05) and thus peculiar to people. But “this work shows that the capacity to represent recursive sequences is present in an animal that will never learn language,” says Stephen Ferrigno, a Harvard University psychologist. Recursion allows one to elaborate a sentence such as “This pandemic is awful” into “This pandemic, which has put so many people out of work, is awful, not to mention a health risk.” Ferrigno and colleagues tested recursion in both monkeys and humans. Ten U.S. adults recognized recursive symbol sequences on a nonverbal task and quickly applied that knowledge to novel sequences of items. To a lesser but still substantial extent, so did 50 U.S. preschoolers and 37 adult Tsimane’ villagers from Bolivia, who had no schooling in math or reading. Those results imply that an ability to grasp recursion must emerge early in life and doesn’t require formal education. Three rhesus monkeys lacked humans’ ease on the task. But after receiving extra training, two of those monkeys displayed recursive learning, Ferrigno’s group says. One of the two animals ended up, on average, more likely to form novel recursive sequences than about three-quarters of the preschoolers and roughly half of the Bolivian villagers. © Society for Science & the Public 2000–2020.

Keyword: Language; Evolution
Link ID: 27332 - Posted: 06.27.2020

By Laura Sanders COVID-19 cases described by U.K. doctors offer a sharper view of the illness’s possible effects on the brain. Strokes, confusion and psychosis were found among a group of 125 people hospitalized with infections of SARS-CoV-2, the coronavirus behind the pandemic. The results, described June 25 in Lancet Psychiatry, come from a group of severely sick people, so they can’t answer how common these types of neurological symptoms may be in a more general population. Still, these details bring scientists closer to better understanding COVID-19. Brain-related symptoms of COVID-19 patients can slip through the cracks. “These relatively rare but incredibly severe complications get missed, like needles in a haystack,” says Benedict Michael, a neurologist at the University of Liverpool in England. So he and his colleagues designed a survey to uncover these symptoms. Sign up for e-mail updates on the latest coronavirus news and research In April, neurologists, stroke physicians, psychiatrists and other doctors across the United Kingdom entered COVID-19 patient details to a centralized database as part of the survey. Targeting these scientific specialties meant that the patients included were likely to have brain-related symptoms. Of the 125 patients described fully, 77 experienced an interruption of blood flow in the brain, most often caused by a blood clot in the brain. Blood clots are a well-known and pernicious COVID-19 complication (SN: 6/23/20), and strokes have been seen in younger people with COVID-19. About a third of the 125 patients had a shift in mental state, including confusion, personality change or depression. Eighteen of 37 patients with altered mental states were younger than 60. So far, it’s unclear exactly how SARS-CoV-2 causes these symptoms. © Society for Science & the Public 2000–2020.

Keyword: Stroke
Link ID: 27330 - Posted: 06.27.2020

Jon Hamilton A neurologist who encased his healthy right arm in a pink fiberglass cast for two weeks has shown how quickly the brain can change after an injury or illness. Daily scans of Dr. Nico Dosenbach's brain showed that circuits controlling his immobilized arm disconnected from the body's motor system within 48 hours. But during the same period, his brain began to produce new signals seemingly meant to keep those circuits intact and ready to reconnect quickly with the unused limb. Dosenbach, an assistant professor at Washington University School of Medicine in St. Louis, repeated the experiment on two colleagues (their casts were purple and blue) and got the same result. In all three people, the disconnected brain circuits quickly reconnected after the cast was removed. The study, published online in the journal Neuron, shows that "within a few days, we can rearrange some of the most fundamental, most basic functional relationships of the brain," Dosenbach says. It suggests it is possible to reverse brain changes caused by disuse of a limb after a stroke or brain injury. The results of the study appear to support the use of something called constraint-induced movement therapy, or CIMT, which helps people – usually children — regain the use of a disabled arm or hand by constraining the other, healthy limb with a sling, splint or cast. Previous studies of CIMT have produced mixed results, in part because they focused on brain changes associated with increased use of a disabled arm, Dosenbach says. "We looked at the effect of actually not using an arm because we thought that was a much more powerful intervention," he says. © 2020 npr

Keyword: Stroke
Link ID: 27311 - Posted: 06.19.2020

By Julia Hollingsworth, CNN (CNN)Laura Molles is so attuned to birds that she can tell where birds of some species are from just by listening to their song. She's not a real-world Dr Doolittle. She's an ecologist in Christchurch, New Zealand, who specializes in a little-known area of science: bird dialects. While some birds are born knowing how to sing innately, many need to be taught how to sing by adults -- just like humans. Those birds can develop regional dialects, meaning their songs sound slightly different depending on where they live. Think Boston and Georgia accents, but for birds. Just as speaking the local language can make it easier for humans to fit in, speaking the local bird dialect can increase a bird's chances of finding a mate. And, more ominously, just as human dialects can sometimes disappear as the world globalizes, bird dialects can be shaped or lost as cities grow. The similarities between human language and bird song aren't lost on Molles -- or on her fellow bird dialect experts. "There are wonderful parallels," said American ornithologist Donald Kroodsma, the author of "Birdsong for the Curious Naturalist: Your Guide to Listening." "Culture, oral traditions -- it's all the same." For centuries, bird song has inspired poets and musicians, but it wasn't until the 1950s that scientists really started paying attention to bird dialects. One of the pioneers of the field was a British-born behaviorist named Peter Marler, who became interested in the subject when he noticed that chaffinches in the United Kingdom sounded different from valley to valley. At first, he transcribed bird songs by hand, according to a profile of him in a Rockefeller University publication. Later, he used a sonagram, which Kroodsma describes on his website as "a musical score for birdsong." ("You really need to see these songs to believe them, our eyes are so much better than our ears," Kroodsma said.) © 2020 Cable News Network.Turner Broadcasting System, Inc.

Keyword: Language; Evolution
Link ID: 27303 - Posted: 06.17.2020

In a nationwide study, NIH funded researchers found that the presence of abnormal bundles of brittle blood vessels in the brain or spinal cord, called cavernous angiomas (CA), are linked to the composition of a person’s gut bacteria. Also known as cerebral cavernous malformations, these lesions which contain slow moving or stagnant blood, can often cause hemorrhagic strokes, seizures, or headaches. Current treatment involves surgical removal of lesions when it is safe to do so. Previous studies in mice and a small number of patients suggested a link between CA and gut bacteria. This study is the first to examine the role the gut microbiome may play in a larger population of CA patients. Led by scientists at the University of Chicago, the researchers used advanced genomic analysis techniques to compare stool samples from 122 people who had at least one CA as seen on brain scans, with those from age- and sex-matched, control non-CA participants, including samples collected through the American Gut Project(link is external). Initially, they found that on average the CA patients had more gram-negative bacteria whereas the controls had more gram-positive bacteria, and that the relative abundance of three gut bacterial species distinguished CA patients from controls regardless of a person’s sex, geographic location, or genetic predisposition to the disease. Moreover, gut bacteria from the CA patients appeared to produce more lipopolysaccharide molecules which have been shown to drive CA formation in mice. According to the authors, these results provided the first demonstration in humans of a “permissive microbiome” associated with the formation of neurovascular lesions in the brain.

Keyword: Stroke
Link ID: 27280 - Posted: 06.04.2020

Ruth Williams With their tiny brains and renowned ability to memorize nectar locations, honeybees are a favorite model organism for studying learning and memory. Such research has indicated that to form long-term memories—ones that last a day or more—the insects need to repeat a training experience at least three times. By contrast, short- and mid-term memories that last seconds to minutes and minutes to hours, respectively, need only a single learning experience. Exceptions to this rule have been observed, however. For example, in some studies, bees formed long-lasting memories after a single learning event. Such results are often regarded as circumstantial anomalies, and the memories formed are not thought to require protein synthesis, a molecular feature of long-term memories encoded by repeated training, says Martin Giurfa of the University of Toulouse. But the anomalous findings, together with research showing that fruit flies and ants can form long-term memories after single experiences, piqued Giurfa’s curiosity. Was it possible that honeybees could reliably do the same, and if so, what molecular mechanisms were required? Giurfa reasoned that the ability to form robust memories might depend on the particular type of bee and the experience. Within a honeybee colony, there are nurses, who clean the hive and feed the young; guards, who patrol and protect the hive; and foragers, who search for nectar. Whereas previous studies have tested bees en masse, Giurfa and his colleagues focused on foragers, tasking them with remembering an experience relevant to their role: an odor associated with a sugary reward. © 1986–2020 The Scientist.

Keyword: Learning & Memory; Evolution
Link ID: 27272 - Posted: 06.01.2020

By Rodrigo Pérez Ortega The left and right sides of our brains store different kinds of memories: The left side specializes in verbal information, for example, while the right side specializes in visual information. But it turns out we’re not the only ones. A new study suggests that ants—like humans, songbirds, and zebrafish—also store different memories in different sides of their tiny brains, in a process called lateralization. Honey bees and bumblebees seem to exhibit lateralization when it comes to memories involving scent. But researchers wanted to know whether other insects were also dividing up the labor of their brains. They trained wood ants (Formica rufa) just as Russian physiologist Ivan Pavlov trained his famous dogs—by treating them with food each time they received a certain signal. To find out whether ants stored visual memories in different parts of their brains, the researchers touched the right antenna, the left antenna, or both, of dozens of ants with a sugary droplet each time they looked at a blue object (above). Then, the researchers tested their memories 10 minutes, 1 hour, and 24 hours after the training. They did this by showing them the blue object and observing whether they extended their mouths, a “thirst” response similar to Pavlov’s dogs salivating. Ants trained with the right antenna had strong thirst responses at the 10-minute mark and lingering responses after 1 hour, but not after that. Ants trained with the left antenna had no response at 10 minutes or 1 hour, but appeared thirsty 24 hours after their training. That suggests that one side of the ant brain stores short-term memories, while the other side stores longer-term ones, the researchers write today in Proceedings of the Royal Society B. © 2020 American Association for the Advancement of Science

Keyword: Laterality; Learning & Memory
Link ID: 27234 - Posted: 05.06.2020

Kerry Grens Several hospitals in the US have observed strokes in a number of patients being treating for coronavirus, leading to concern that the infection may be causing devastating blockages in the brain. For at least two facilities, these events account for a spike in stroke cases among middle-aged patients. “Our report shows a seven-fold increase in incidence of sudden stroke in young patients during the past two weeks,” Thomas Oxley, a neurosurgeon at Mount Sinai Health System in New York who describes five of his patients in an upcoming paper in the New England Journal of Medicine, tells CNN. “Most of these patients have no past medical history and were at home with either mild symptoms (or in two cases, no symptoms) of Covid.” Although the numbers of stroke incidents among coronavirus patients remains low, The Washington Post notes that three medical centers in the US will be publishing reports on dozens of COVID-19 patients who experienced strokes. And these appear to be the most serious kind of stroke, called a large vessel occlusion, which might account for the surge in the number of people who have died at home during the pandemic, but this cannot be confirmed. Thomas Jefferson University Hospitals and NYU Langone Health found that 40 percent of the 12 people treated for large vessel blockage who also tested positive for SARS-CoV-2 were under age 50, according to the Post. “We are used to thinking of 60 as a young patient when it comes to large vessel occlusions,” Eytan Raz of NYU Langone tells the newspaper. “We have never seen so many in their 50s, 40s and late 30s.” © 1986–2020 The Scientist.

Keyword: Stroke
Link ID: 27217 - Posted: 04.29.2020

By Laura Sanders Neuroscientists love a good metaphor. Through the years, plumbing, telegraph wires and computers have all been enlisted to help explain how the brain operates, neurobiologist and historian Matthew Cobb writes in The Idea of the Brain. And like any metaphor, those approximations all fall short. Cobb leads a fascinating tour of how concepts of the brain have morphed over time. His writing is clear, thoughtful and, when called for, funny. He describes experiments by neurosurgeon Wilder Penfield, who zapped awake patients’ brains with electricity to provoke reactions. Zapping certain places consistently dredged up memories, which Cobb calls “oneiric experiences.” His footnote on the term: “Look it up. It’s exactly the right word.” I did, and it was. Cobb runs though the history of certain concepts used to explain how the brain works, including electricity, evolution and neurons. Next comes a section on the present, which includes discussions of memory, circuits and consciousness. Cobb offers tastes of the latest research, and a heavy dose of realism. Memory studies have made progress, but “we are still far from understanding what is happening when we remember,” Cobb writes. Despite big efforts, “we still only dimly understand what is going on when we see.” Our understanding of how antidepressants work? “Virtually non-existent.” This real talk is refreshing, and Cobb uses it to great effect to argue that neuroscience is stymied. “There have been many similar moments in the past, when brain researchers became uncertain about how to proceed,” he writes. Scientists have amassed an impressive stockpile of brain facts, but a true understanding of how the brain works eludes us. © Society for Science & the Public 2000–2020

Keyword: Miscellaneous
Link ID: 27206 - Posted: 04.22.2020

By Lydia Denworth, It is lunchtime on a Sunday in January. At a long table inside a delicatessen in midtown Manhattan, a group of young people sit together over sandwiches and salads. Most of them have their phones out. One boy wears headphones around his neck. But there is less conversation than you might expect from a typical group of friends: One of the boys seems to talk only to himself, and a girl looks anxious and occasionally flaps her hands. The young people in this group are all on the spectrum. They met through a program organized by the nonprofit Actionplay, in which young people with autism or other disabilities work together to write and stage a musical. Each Sunday, the members refine characters and the script, block scenes and compose songs—and then some of them head across the street to have lunch together. “You meet other people just like you,” says Lexi Spindel, 15. The members share a group text in which they call themselves the Wrecking Crew. A few months ago, six of the girls went to see the movie “Frozen II” together. And Lexi and Actionplay veteran Adelaide DeSole, 21, spent a long afternoon at the Spindels’ apartment over the holiday season. The two young women played games and watched “SpongeBob SquarePants” and “Kung Fu Panda” on television. “That was the first time my daughter had a friend over,” says Lexi’s father, Jay Spindel. “That never happened before Actionplay.” © 2020 Simons Foundation

Keyword: Autism
Link ID: 27178 - Posted: 04.10.2020

Nathan Denette/The Canadian Press While the new coronavirus is known to cause respiratory illness, some scientists suggest it can also potentially lead to brain and nerve damage in certain patients. Beyond the typical symptoms of COVID-19, including fever, cough and difficulty breathing, doctors around the world have reported cases of infected patients with an array of neurological problems, including stroke, seizures, anosmia, or a loss of smell, and encephalopathy, a broad term used to describe brain damage or dysfunction. Since these reports have so far been limited to anecdotal case studies, it is still too early to know whether the virus is to blame for these neurological symptoms, said clinical epidemiologist Jose Tellez-Zenteno, a professor of neurology at the University of Saskatchewan. Nevertheless, he said, it’s important for the public and health care providers to know this is a possibility. “The virus can go to the brain potentially,” Dr. Tellez-Zenteno said. “And not only for neurologists, but for [front-line] doctors …, they have to be aware that neurological complications can happen and be ready to diagnose and ready to treat, if there is some treatment for them.” He noted that in one study of 214 hospitalized COVID-19 patients in Wuhan, China, researchers reported more than 35 per cent had neurological complications, including decreased levels of consciousness, stroke and muscle damage. These were more likely to occur among the hospitalized patients who were severely ill with COVID-19. Dr. Tellez-Zenteno emphasized that the vast majority of individuals who catch COVID-19 have mild or no symptoms. © Copyright 2020 The Globe and Mail Inc.

Keyword: Stroke
Link ID: 27175 - Posted: 04.07.2020

By Roni Caryn Rabin Neurologists around the world say that a small subset of patients with Covid-19 are developing serious impairments of the brain. Although fever, cough and difficulty breathing are the typical hallmarks of infection with the new coronavirus, some patients exhibit altered mental status, or encephalopathy, a catchall term for brain disease or dysfunction that can have many underlying causes, as well as other serious conditions. These neurological syndromes join other unusual symptoms, such as diminished sense of smell and taste as well as heart ailments. In early March, a 74-year-old man came to the emergency room in Boca Raton, Fla., with a cough and a fever, but an X-ray ruled out pneumonia and he was sent home. The next day, when his fever spiked, family members brought him back. He was short of breath, and could not tell doctors his name or explain what was wrong — he had lost the ability to speak. The patient, who had chronic lung disease and Parkinson’s, was flailing his arms and legs in jerky movements, and appeared to be having a seizure. Doctors suspected he had Covid-19, and were eventually proven right when he was finally tested. On Tuesday, doctors in Detroit reported another disturbing case involving a female airline worker in her late 50s with Covid-19. She was confused, and complained of a headache; she could tell the physicians her name but little else, and became less responsive over time. Brain scans showed abnormal swelling and inflammation in several regions, with smaller areas where some cells had died. Physicians diagnosed a dangerous condition called acute necrotizing encephalopathy, a rare complication of influenza and other viral infections. “The pattern of involvement, and the way that it rapidly progressed over days, is consistent with viral inflammation of the brain,” Dr. Elissa Fory, a neurologist with Henry Ford Health System, said through an email. “This may indicate the virus can invade the brain directly in rare circumstances.” The patient is in critical condition. © 2020 The New York Times Company

Keyword: Neuroimmunology; Stroke
Link ID: 27164 - Posted: 04.03.2020

Nicola Davis Reading minds has just come a step closer to reality: scientists have developed artificial intelligence that can turn brain activity into text. While the system currently works on neural patterns detected while someone is speaking aloud, experts say it could eventually aid communication for patients who are unable to speak or type, such as those with locked in syndrome. “We are not there yet but we think this could be the basis of a speech prosthesis,” said Dr Joseph Makin, co-author of the research from the University of California, San Francisco. Writing in the journal Nature Neuroscience, Makin and colleagues reveal how they developed their system by recruiting four participants who had electrode arrays implanted in their brain to monitor epileptic seizures. These participants were asked to read aloud from 50 set sentences multiple times, including “Tina Turner is a pop singer”, and “Those thieves stole 30 jewels”. The team tracked their neural activity while they were speaking. This data was then fed into a machine-learning algorithm, a type of artificial intelligence system that converted the brain activity data for each spoken sentence into a string of numbers. To make sure the numbers related only to aspects of speech, the system compared sounds predicted from small chunks of the brain activity data with actual recorded audio. The string of numbers was then fed into a second part of the system which converted it into a sequence of words. © 2020 Guardian News & Media Limited

Keyword: Language; Brain imaging
Link ID: 27155 - Posted: 03.31.2020

By Eva Frederick They’re the undertakers of the bee world: a class of workers that scours hives for dead comrades, finding them in the dark in as little as 30 minutes, despite the fact that the deceased haven’t begun to give off the typical odors of decay. A new study may reveal how they do it. “The task of undertaking is fascinating” and the new work is “pretty cool,” says Jenny Jandt, a behavioral ecologist at the University of Otago, Dunedin, who was not involved with the study. Wen Ping, an ecologist at the Chinese Academy of Sciences’s Xishuangbanna Tropical Botanical Garden, wondered whether a specific type of scent molecule might help undertaker bees find their fallen hive mates. Ants, bees, and other insects are covered in compounds called cuticular hydrocarbons (CHCs), which compose part of the waxy coating on their cuticles (the shiny parts of their exoskeletons) and help prevent them from drying out. While the insects are alive, these molecules are continually released into the air and are used to recognize fellow hive members. Wen speculated that less of the pheromones were being released into the air after a bee died and its body temperature decreased. When he used chemical methods of detecting gases to test this hypothesis, he confirmed that cooled dead bees were indeed emitting fewer volatile CHCs than living bees. © 2020 American Association for the Advancement of Science.

Keyword: Chemical Senses (Smell & Taste); Animal Communication
Link ID: 27138 - Posted: 03.24.2020