Chapter 2. Functional Neuroanatomy: The Nervous System and Behavior

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Nicola Davis A new organ involved in the sensation of pain has been discovered by scientists, raising hopes that it could lead to the development of new painkilling drugs. Researchers say they have discovered that the special cells that surround the pain-sensing nerve cells that extend into the outer layer of skin appear to be involved in sensing pain – a discovery that points to a new organ behind the feeling of “ouch!”. The scientists say the finding offers new insight into pain and could help answer longstanding conundrums. “The major question for us now is whether these cells are actually the cause for certain kinds of chronic pain disorders,” Prof Patrik Ernfors, a co-author of the research from the Karolinska Institute in Sweden, told the Guardian. Writing in the journal Science, the researchers reveal how they examined the nature of cells in the skin that, they say, have largely been overlooked. These are a type of Schwann cell, which wrap around and engulf nerve cells and help to keep them alive. The study has revealed these Schwann cells have an octopus-like shape. After examining tissues, the team found the body of the cells sits below the outer layer of the skin, but that the cells have long extensions that wrap around the ends of pain-sensing nerve cells that extend up into the epidermis, the outer layer of the skin. The scientists were surprised at the findings because it has long been believed that the endings of nerve cells in the epidermis were bare or unwrapped. “In the pain field, we talk about free nerve endings that are responsible for pain sensation. But actually they are not free,” Ernfors said. © 2019 Guardian News & Media Limited

Keyword: Pain & Touch; Glia
Link ID: 26507 - Posted: 08.16.2019

Laura Sanders The golf ball–sized chunk of brain is not cooperating. It’s thicker than usual, and bloodier. One side has a swath of tissue that looks, to my untrained eye, like gristle. Nick Dee, the neuroscientist charged with quickly cutting the chunk into neat pieces, confers with his colleagues. “We can trim off that ugliness on the side,” he says. The “ugliness” is the brain’s connective tissue called white matter. To produce useful slices for experiments, the brain tissue must be trimmed, superglued to a lipstick-sized base and then fed into a lab version of a deli slicer. But this difficult chunk isn’t cutting nicely. Dee and colleagues pull it off the base, trim it again and reglue. Half an hour earlier, this piece of neural tissue was tucked inside a 41-year-old woman’s head, on her left side, just above the ear. Surgeons removed the tissue to reach a deeper part of her brain thought to be causing severe seizures. Privacy rules prevent me from knowing much about her; I don’t know her name, much less her first memory, favorite meal or sense of humor. But within this piece of tissue, which the patient generously donated, are clues to how her brain — all of our brains, really — create the mind. Dee’s team is working fast because this piece of brain is alive. Some of the cells can still behave as if they are a part of a person’s brain, which means they hold enormous potential for scientists who want to understand how we remember, plan, behave and feel. After Dee and his team do their part, pieces of the woman’s brain will be whisked into the hands of eager scientists, where the cells will be photographed, zapped with electricity, relieved of their genetic material and even infected with viruses that make them glow green and red. © Society for Science & the Public 2000 - 2019

Keyword: Brain imaging; Evolution
Link ID: 26490 - Posted: 08.12.2019

By Paula Span Juli Engel was delighted when a neurologist recommended a PET scan to determine whether amyloid — the protein clumps associated with an increased risk of Alzheimer’s disease — was accumulating in her mother’s brain. “My internal response was, ‘Yay!’” said Ms. Engel, 65, a geriatric care manager in Austin, Tex., who has been making almost monthly trips to help her mother in Florida. “He’s using every tool to try to determine what’s going on.” Sue Engel, who’s 83 and lives in a retirement community in Leesburg, Fla., has been experiencing memory problems and other signs of cognitive decline for several years. Her daughter checked off the warning signs: her mother has been financially exploited, suffered an insurance scam, caused an auto accident. Medicare officials decided in 2013, shortly after PET (positron emission tomography) amyloid imaging became available, that they lacked evidence of its health benefits. So outside of research trials, Medicare doesn’t cover the scans’ substantial costs ($5,000 to $7,000, the Alzheimer’s Association says); private insurers don’t, either. Juli Engel thinks Medicare should reimburse for the scan, but “if necessary, we’ll pay for it out of pocket,” she said. Her mother already has an Alzheimer’s diagnosis and is taking a commonly prescribed dementia drug. So she probably doesn’t meet the criteria developed by the Alzheimer’s Association and nuclear medicine experts, which call for PET scans only in cases of unexplained or unusual symptoms and unclear diagnoses. But as evidence mounts that brain damage from Alzheimer’s begins years before people develop symptoms, worried patients and their families may start turning to PET scans to learn if they have this biomarker. © 2019 The New York Times Company

Keyword: Alzheimers; Brain imaging
Link ID: 26484 - Posted: 08.03.2019

Ian Sample Science editor Doctors have turned the brain signals for speech into written sentences in a research project that aims to transform how patients with severe disabilities communicate in the future. The breakthrough is the first to demonstrate how the intention to say specific words can be extracted from brain activity and converted into text rapidly enough to keep pace with natural conversation. In its current form, the brain-reading software works only for certain sentences it has been trained on, but scientists believe it is a stepping stone towards a more powerful system that can decode in real time the words a person intends to say. A neuroscientist explains: the need for ‘empathetic citizens’ - podcast Doctors at the University of California in San Francisco took on the challenge in the hope of creating a product that allows paralysed people to communicate more fluidly than using existing devices that pick up eye movements and muscle twitches to control a virtual keyboard. “To date there is no speech prosthetic system that allows users to have interactions on the rapid timescale of a human conversation,” said Edward Chang, a neurosurgeon and lead researcher on the study published in the journal Nature. The work, funded by Facebook, was possible thanks to three epilepsy patients who were about to have neurosurgery for their condition. Before their operations went ahead, all three had a small patch of tiny electrodes placed directly on the brain for at least a week to map the origins of their seizures. © 2019 Guardian News & Media Limited

Keyword: Brain imaging; Language
Link ID: 26472 - Posted: 07.31.2019

By Sarah White | Some five ounces of clear fluid fills the spaces between your brain and your skull. This brain juice, or cerebrospinal fluid, cushions against injury, supplies nutrients and clears away waste. Your body can make as much as a pint of fresh stuff every day to replace the old. But for 150 years, scientists have puzzled over how the used cerebrospinal fluid leaves the brain to make room for more. New research, published Wednesday in Nature, has finally deciphered this brain drain process. As a result, it’s also inching us closer to understanding Alzheimer’s and other neurodegenerative diseases. South Korean scientists, led by Gou Young Koh, completed the puzzle by studying our immune system’s superhighway, dubbed the lymphatic system. They were able to trace the cerebrospinal fluid’s one-directional path in mice, from its origin in the brain into lymph nodes in the neck. The key conduit? Lymphatic vessels at the bottom of the skull, in the brain’s outer layers. Before now, neuroscientists thought cerebrospinal fluid drained through lymphatic vessels on top of the brain or ones exiting through the nasal cavity. No one had managed to carefully examine the lymphatic vessels on the bottom of the brain because they’re so close to bones and delicate blood vessels. But by having a neurosurgeon on their team, the researchers could get close enough to identify what was so special about these bottom lymphatic vessels and see what makes them ideal for draining cerebrospinal fluid.

Keyword: Alzheimers
Link ID: 26455 - Posted: 07.27.2019

Abby Olena For years, scientists thought the brain lacked a lymphatic system, raising questions about how fluid, macromolecules, and immune cells escape the organ. In 2015, two studies in mice provided evidence that the brain does in fact have a traditional lymphatic system in the outermost layer of the meninges—the coverings that protect the brain and help keep its shape—but scientists hadn’t yet figured out the exact exit route cerebrospinal fluid (CSF) and molecules take. In a study published today (July 24) in Nature, researchers show that there is a hot spot of meningeal lymphatic vessels at the base of the rodent skull that is specialized to drain CSF and allow proteins and other large molecules to leave the brain. “What they showed very nicely is that the system of meningeal lymphatics is the drainage system of the CSF of the central nervous system,” says Jonathan Kipnis, a neuroscientist at the University of Virginia who did not participate in the new study, but coauthored the first 2015 study. “We’re just scratching really the surface of understanding what these vessels are doing.” “I’m actually quite relieved because when we published in 2015 . . . we got a lot of contrasting comments and some people were not convinced that the lymphatics really can be involved in cerebrospinal fluid drainage because there was a lot of literature telling otherwise,” Kari Alitalo of the University of Helsinki tells The Scientist. Alitalo coauthored the second 2015 paper describing the brain’s lymphatic system, but was not involved in the current study. © 1986–2019 The Scientist

Keyword: Brain imaging
Link ID: 26452 - Posted: 07.26.2019

Ian Sample Science editor Brain scans of US embassy staff who became ill in mysterious circumstances while serving in Cuba have found potential abnormalities that may be related to their symptoms. The scans taken from 40 US government workers who suffered strange concussion-like symptoms during their deployment to Havana revealed that particular brain features looked different to those in healthy volunteers. Images of the diplomats’ brains found that on average they had lower volumes of white matter, the tissue made from nerve bundles that send messages around the brain. They also showed micro-structural differences and other changes that could affect auditory and visuospatial processing, doctors said. But the medical team that performed the scans said the findings were not conclusive. They do not match what is normally seen in brain injuries and the severity of symptoms did not vary with the extent of the brain differences spotted. “It’s a unique presentation that we have not seen before,” said Ragini Verma, a professor of biomedical imaging on the team at the University of Pennsylvania. “What caused it? I’m completely unequipped to answer that.” Independent experts agreed the findings were inconclusive and said it was still unclear whether the diplomats were victims of any attack or had suffered related brain injuries. The apparent abnormalities might have pre-dated the attacks, they said, and could have more mundane explanations such as anxiety or depression. One said the study did not meet the usual standards for publication. © 2019 Guardian News & Media Limited

Keyword: Brain imaging; Brain Injury/Concussion
Link ID: 26446 - Posted: 07.24.2019

Ed Yong On July 22, 2009, the neuroscientist Henry Markram walked onstage at the TEDGlobal conference in Oxford, England, and told the audience that he was going to simulate the human brain, in all its staggering complexity, in a computer. His goals were lofty: “It’s perhaps to understand perception, to understand reality, and perhaps to even also understand physical reality.” His timeline was ambitious: “We can do it within 10 years, and if we do succeed, we will send to TED, in 10 years, a hologram to talk to you.” If the galaxy-brain meme had existed then, it would have been a great time to invoke it. It’s been exactly 10 years. He did not succeed. One could argue that the nature of pioneers is to reach far and talk big, and that it’s churlish to single out any one failed prediction when science is so full of them. (Science writers joke that breakthrough medicines and technologies always seem five to 10 years away, on a rolling window.) But Markram’s claims are worth revisiting for two reasons. First, the stakes were huge: In 2013, the European Commission awarded his initiative—the Human Brain Project (HBP)—a staggering 1 billion euro grant (worth about $1.42 billion at the time). Second, the HBP’s efforts, and the intense backlash to them, exposed important divides in how neuroscientists think about the brain and how it should be studied. Markram’s goal wasn’t to create a simplified version of the brain, but a gloriously complex facsimile, down to the constituent neurons, the electrical activity coursing along them, and even the genes turning on and off within them. From the outset, the criticism to this approach was very widespread, and to many other neuroscientists, its bottom-up strategy seemed implausible to the point of absurdity.

Keyword: Brain imaging
Link ID: 26440 - Posted: 07.23.2019

By Tanya Lewis Late on Tuesday evening, Elon Musk, the charismatic and eccentric CEO of SpaceX and Tesla, took to the stage at the California Academy of Sciences to make a big announcement. This time, he was not unveiling a new rocket or electric car but a system for recording the activity of thousands of neurons in the brain. With typical panache, Musk talked about putting this technology into a human brain by as early as next year. The work is the product of Neuralink, a company Musk founded in 2016 to develop a high-bandwidth, implantable brain-computer interface (BCI). He says the initial goal is to enable people with quadriplegia to control a computer or smartphone using just their thoughts. But Musk’s vision is much more ambitious than that: he seeks to enable humans to “merge” with AI, giving people superhuman intelligence—an objective that is much more hype than an actual plan for new technology development. Neuralink prototype device. Credit: Neuralink On a more practical note, “the goal is to record from and stimulate [signals called] spikes in neurons” with an order of magnitude more bandwidth than what has been done to date and to have it be safe, Musk said at Tuesday’s event, which was livestreamed. Advertisement The system unveiled last night was a long way from Musk’s sci-fi vision. But it was nonetheless marked an impressive technical development. The team says it has now developed arrays with a very large number of “channels”—up to 3,072 flexible electrodes—which can be implanted in the brain’s outer layer, or cortex, using a surgical robot (a version of which was described as a “sewing machine” in a preprint paper posted on bioRxiv earlier this year). The electrodes are packaged in a small, implantable device containing custom-built integrated circuits, which connects to a USB port outside the brain (the team hopes to ultimately make the port wireless). © 2019 Scientific American

Keyword: Brain imaging; Regeneration
Link ID: 26427 - Posted: 07.18.2019

Laura Sanders Over 100 hours of scanning has yielded a 3-D picture of the whole human brain that’s more detailed than ever before. The new view, enabled by a powerful MRI, has the resolution potentially to spot objects that are smaller than 0.1 millimeters wide. “We haven’t seen an entire brain like this,” says electrical engineer Priti Balchandani of the Icahn School of Medicine at Mount Sinai in New York City, who was not involved in the study. “It’s definitely unprecedented.” The scan shows brain structures such as the amygdala in vivid detail, a picture that might lead to a deeper understanding of how subtle changes in anatomy could relate to disorders such as post-traumatic stress disorder. To get this new look, researchers at Massachusetts General Hospital in Boston and elsewhere studied a brain from a 58-year-old woman who died of viral pneumonia. Her donated brain, presumed to be healthy, was preserved and stored for nearly three years. Before the scan began, researchers built a custom spheroid case of urethane that held the brain still and allowed interfering air bubbles to escape. Sturdily encased, the brain then went into a powerful MRI machine called a 7 Tesla, or 7T, and stayed there for almost five days of scanning. |© Society for Science & the Public 2000 - 2019.

Keyword: Brain imaging
Link ID: 26401 - Posted: 07.09.2019

Jon Hamilton The squiggly blue lines visible in the neurons are an Alzheimer's biomarker called tau. The brownish clumps are amyloid plaques. Courtesy of the National Institute on Aging/National Institutes of Health Alzheimer's disease begins altering the brain long before it affects memory and thinking. So scientists are developing a range of tests to detect these changes in the brain, which include an increase in toxic proteins, inflammation and damage to the connections between brain cells. The tests rely on biomarkers, shorthand for biological markers, that signal steps along the progression of disease. These new tests are already making Alzheimer's diagnosis more accurate, and helping pharmaceutical companies test new drugs. "For the future, we hope that we might be able to use these biomarkers in order to stop or delay the memory changes from ever happening," says Maria Carrillo, chief science officer of the Alzheimer's Association. (The association is a recent NPR sponsor.) The first Alzheimer's biomarker test was approved by the Food and Drug Administration in in 2012. It's a dye called Amyvid that reveals clumps of a protein called amyloid. These amyloid plaques are a hallmark of Alzheimer's. © 2019 npr

Keyword: Alzheimers; Brain imaging
Link ID: 26390 - Posted: 07.05.2019

By Knvul Sheikh The tiny, transparent roundworm known as Caenorhabditis elegans is roughly the size of a comma. Its entire body is made up of just about 1,000 cells. A third are brain cells, or neurons, that govern how the worm wriggles and when it searches for food — or abandons a meal to mate. It is one of the simplest organisms with a nervous system. The circuitry of C. elegans has made it a common test subject among scientists wanting to understand how the nervous system works in other animals. Now, a team of researchers has completed a map of all the neurons, as well as all 7,000 or so connections between those neurons, in both sexes of the worm. “It’s a major step toward understanding how neurons interact with each other to give rise to different behaviors,” said Scott Emmons, a developmental biologist at the Albert Einstein College of Medicine in New York who led the research. Structure dictates function in several areas of biology, Dr. Emmons said. The shape of wings provided insight into flight, the helical form of DNA revealed how genes are coded, and the structure of proteins suggested how enzymes bind to targets in the body. It was this concept that led biologist Sydney Brenner to start cataloging the neural wiring of worms in the 1970s. He and his colleagues preserved C. elegans in agar and osmium fixative, sliced up their bodies like salami and photographed their cells with a powerful electron microscope. © 2019 The New York Times Company

Keyword: Brain imaging; Development of the Brain
Link ID: 26389 - Posted: 07.04.2019

By Benedict Carey Doctors have known for years that some patients who become unresponsive after a severe brain injury nonetheless retain a “covert consciousness,” a degree of cognitive function that is important to recovery but is not detectable by standard bedside exams. As a result, a profound uncertainty often haunts the wrenching decisions that families must make when an unresponsive loved one needs life support, an uncertainty that also amplifies national debates over how to determine when a patient in this condition can be declared beyond help. Now, scientists report the first large-scale demonstration of an approach that can identify this hidden brain function right after injury, using specialized computer analysis of routine EEG recordings from the skull. The new study, published Wednesday in the New England Journal of Medicine, found that 15 percent of otherwise unresponsive patients in one intensive care unit had covert brain activity in the days after injury. Moreover, these patients were nearly four times more likely to achieve partial independence over the next year with rehabilitation, compared to patients with no activity. The EEG approach will not be widely available for some time, due in part to the technical expertise required, which most I.C.U.’s don’t yet have. And doctors said the test would not likely resolve the kind of high-profile cases that have taken on religious and political dimensions, like that of Terri Schiavo, the Florida woman whose condition touched off an ethical debate in the mid-2000s, or Karen Ann Quinlan, a New Jersey woman whose case stirred similar sentiments in the 1970s. Those debates centered less on recovery than on the definition of life and the right to die; the new analysis presumes some resting level of EEG, and that signal in both women was virtually flat. © 2019 The New York Times Company

Keyword: Consciousness; Brain imaging
Link ID: 26363 - Posted: 06.27.2019

Nicola Davis Changes in the brain that can be spotted years before physical symptoms of Parkinson’s disease occur might act as an early warning sign for the condition, researchers say. It is thought that about 145,000 people in the UK are living with Parkinson’s disease, a neurological condition that can lead to mobility problems, including slowness and tremors, as well as other symptoms such as memory difficulties. There are treatments to help manage symptoms but as yet the disease cannot be slowed or cured. The researchers, based at King’s College London, say the latest findings could eventually lead to new ways to identify people who might go on to develop Parkinson’s; the discoveries could also confirm diagnoses, monitor the disease progression, and aid the development and testing of drugs. Those developments could be some way off though, some scientists have said. Most of the time Parkinson’s appears to have no known cause, so people affected by the disease are not studied before their symptoms appear. But the King’s College studies concerned with genetic mutations making the development of Parkinson’s disease more likely, could point to the warning signs. Marios Politis, a professor and lead author of the research, said: “If you carry the gene [SNCA] it means it is almost certain you are going to develop Parkinson’s in the course of your life.” © 2019 Guardian News & Media Limited

Keyword: Parkinsons; Brain imaging
Link ID: 26344 - Posted: 06.20.2019

Sara Reardon A medical imaging device that can create 3D renderings of the entire human body in as little as 20 seconds could soon be used for a wide variety of research and clinical applications. The modified positron emission tomography (PET) scanner is faster than conventional PET scans — which can take an average of 20 minutes — and requires less radiation exposure for the person being imaged. Researchers presented video taken by the device last week at the US National Institutes of Health’s High-Risk, High-Reward Research Symposium in Bethesda, Maryland. The machine could be especially helpful for imaging children, who tend to wiggle around inside a scanner and ruin the measurements, as well as for studies of how drugs move through the body, says Sanjay Jain, a paediatrician and infectious-disease physician at Johns Hopkins University in Baltimore, Maryland. Standard PET scanners detect γ-rays from radioactive tracers that doctors inject into the person being imaged. The person’s cells take up the molecule and break it down, releasing two γ-rays. A ring-shaped detector positioned around the person measures the angle and speed of the rays and reconstructs their origin, creating a 3D map of the cells that are metabolizing the molecule. The ring is just 25 centimetres thick, however, so physicians can image only a small portion of the body at a time. Capturing larger areas requires them to dose the person with more of the radioactive molecule ― it decays quickly, which means the signal fades fast ― and move them back and forth through the ring. © 2019 Springer Nature Publishing AG

Keyword: Brain imaging
Link ID: 26328 - Posted: 06.14.2019

By Lindsey Bever Doctors had broken the disheartening news to Rachel Palma, explaining that the lesion on her brain was suspected to be a tumor, and her scans suggested that it was cancerous. Palma, a newlywed entering a new chapter in her life, said she was in shock, unwilling to believe it was true. In September, scrubbed-up surgeons in an operating room at Mount Sinai Hospital in New York City opened Palma’s cranium and steeled themselves for a malignant brain tumor, said Jonathan Rasouli, chief neurosurgery resident at the Icahn School of Medicine at Mount Sinai. But instead, Rasouli said, they saw an encapsulated mass resembling a quail egg. “We were all saying, ‘What is this?’ ” Rasouli recalled Thursday in a phone interview with The Washington Post. “It was very shocking. We were scratching our heads, surprised at what it looked like.” The surgeons removed it from Palma’s brain and placed it under a microscope to get a closer look. Then they sliced into it — and found a baby tapeworm. Palma, from Middletown, N.Y., said she had mixed emotions about it. “Of course I was grossed out,” the 42-year-old said Thursday, explaining that no one wants to think there’s a tapeworm growing inside an egg in his or her brain. “But of course, I was also relieved. It meant that no further treatment was necessary.” A scan showing the tapeworm in Rachel Palma's brain. (Mount Sinai Health System) © 1996-2019 The Washington Post

Keyword: Miscellaneous
Link ID: 26308 - Posted: 06.07.2019

Sandeep Ravindran In 2012, computer scientist Dharmendra Modha used a powerful supercomputer to simulate the activity of more than 500 billion neurons—more, even, than the 85 billion or so neurons in the human brain. It was the culmination of almost a decade of work, as Modha progressed from simulating the brains of rodents and cats to something on the scale of humans. The simulation consumed enormous computational resources—1.5 million processors and 1.5 petabytes (1.5 million gigabytes) of memory—and was still agonizingly slow, 1,500 times slower than the brain computes. Modha estimates that to run it in biological real time would have required 12 gigawatts of energy, about six times the maximum output capacity of the Hoover Dam. “And yet, it was just a cartoon of what the brain does,” says Modha, chief scientist for brain-inspired computing at IBM Almaden Research Center in northern California. The simulation came nowhere close to replicating the functionality of the human brain, which uses about the same amount of power as a 20-watt lightbulb. Since the early 2000s, improved hardware and advances in experimental and theoretical neuroscience have enabled researchers to create ever larger and more-detailed models of the brain. But the more complex these simulations get, the more they run into the limitations of conventional computer hardware, as illustrated by Modha’s power-hungry model. © 1986–2019 The Scientist

Keyword: Robotics
Link ID: 26269 - Posted: 05.28.2019

By Kenneth Miller A model of Ben Barres’ brain sits on the windowsill behind his desk at Stanford University School of Medicine. To a casual observer, there’s nothing remarkable about the plastic lump, 3-D-printed from an MRI scan. Almost lost in the jumble of papers, coffee mugs, plaques and trophies that fill the neurobiologist’s office, it offers no hint about what Barres’ actual gray matter has helped to accomplish: a transformation of our understanding of brains in general, and how they can go wrong. Barres is a pioneer in the study of glia. This class of cells makes up 90 percent of the human brain, but gets far less attention than neurons, the nerve cells that transmit our thoughts and sensations at lightning speed. Glia were long regarded mainly as a maintenance crew, performing such unglamorous tasks as ferrying nutrients and mopping up waste, and occasionally mounting a defense when the brain faced injury or infection. Over the past two decades, however, Barres’ research has revealed that they actually play central roles in sculpting the developing brain, and in guiding neurons’ behavior at every stage of life. “He has made one shocking, revolutionary discovery after another,” says biologist Martin Raff, emeritus professor at University College London, whose own work helped pave the way for those advances. Recently, Barres and his collaborators have made some discoveries that may revolutionize the treatment of neurodegenerative ailments, from glaucoma and multiple sclerosis to Alzheimer’s disease and stroke. What drives such disorders, their findings suggest, is a process in which glia turn from nurturing neurons to destroying them. Human trials of a drug designed to block that change are just beginning.

Keyword: Glia; Learning & Memory
Link ID: 26258 - Posted: 05.22.2019

By Nathaniel Scharping | Don’t get a big head, your mother may have told you. That’s good advice, but it comes too late for most of us. Humans have had big heads, relatively speaking, for hundreds of thousands of years, much to our mothers’ dismay. Our oversize noggins are a literal pain during childbirth. Babies have to twist and turn as they exit the birth canal, sometimes leading to complications that necessitate surgery. And while big heads can be painful for the mother, they can downright transformative for babies: A fetus’ pliable skull deforms during birth like putty squeezed through a tube to allow it to pass into the world. This cranial deformation has been known about for a long time, but in a new study, scientists from France and the U.S. actually watched it happen using an MRI machine during labor. The images, published in a study in PLOS One, show how the skulls (and brains) of seven infants squished and warped during birth to pass through the birth canal. They also shine new light on how much our skulls change shape as we’re born. The researchers recruited pregnant women in France to undergo an MRI a few weeks before pregnancy and another in the minutes before they began to actually give birth. In total, seven women were scanned in the second stage of labor, when the baby begins to make its way out of the uterus. They were then rushed to the maternity ward to actually complete giving birth.

Keyword: Development of the Brain; Brain imaging
Link ID: 26252 - Posted: 05.20.2019

By Benedict Carey “In my head, I churn over every sentence ten times, delete a word, add an adjective, and learn my text by heart, paragraph by paragraph,” wrote Jean-Dominique Bauby in his memoir, “The Diving Bell and the Butterfly.” In the book, Mr. Bauby, a journalist and editor, recalled his life before and after a paralyzing stroke that left him virtually unable to move a muscle; he tapped out the book letter by letter, by blinking an eyelid. Thousands of people are reduced to similarly painstaking means of communication as a result of injuries suffered in accidents or combat, of strokes, or of neurodegenerative disorders such as amyotrophic lateral sclerosis, or A.L.S., that disable the ability to speak. Now, scientists are reporting that they have developed a virtual prosthetic voice, a system that decodes the brain’s vocal intentions and translates them into mostly understandable speech, with no need to move a muscle, even those in the mouth. (The physicist and author Stephen Hawking used a muscle in his cheek to type keyboard characters, which a computer synthesized into speech.) “It’s formidable work, and it moves us up another level toward restoring speech” by decoding brain signals, said Dr. Anthony Ritaccio, a neurologist and neuroscientist at the Mayo Clinic in Jacksonville, Fla., who was not a member of the research group. Researchers have developed other virtual speech aids. Those work by decoding the brain signals responsible for recognizing letters and words, the verbal representations of speech. But those approaches lack the speed and fluidity of natural speaking. The new system, described on Wednesday in the journal Nature, deciphers the brain’s motor commands guiding vocal movement during speech — the tap of the tongue, the narrowing of the lips — and generates intelligible sentences that approximate a speaker’s natural cadence. © 2019 The New York Times Company

Keyword: Language; Robotics
Link ID: 26174 - Posted: 04.25.2019