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By Liam Drew The first person to receive a brain-monitoring device from neurotechnology company Neuralink can control a computer cursor with their mind, Elon Musk, the firm’s founder, revealed this week. But researchers say that this is not a major feat — and they are concerned about the secrecy around the device’s safety and performance. The company is “only sharing the bits that they want us to know about”, says Sameer Sheth, a neurosurgeon specializing in implanted neurotechnology at Baylor College of Medicine in Houston, Texas. “There’s a lot of concern in the community about that.” Threads for thoughts Musk announced on 29 January that Neuralink had implanted a brain–computer interface (BCI) into a human for the first time. Neuralink, which is headquartered in Fremont, California, is the third company to start long-term trials in humans. Some implanted BCIs sit on the brain’s surface and record the average firing of populations of neurons, but Neuralink’s device, and at least two others, penetrates the brain to record the activity of individual neurons. Neuralink’s BCI contains 1,024 electrodes — many more than previous systems — arranged on innovative pliable threads. The company has also produced a surgical robot for inserting its device. But it has not confirmed whether that system was used for the first human implant. Details about the first recipient are also scarce, although Neuralink’s volunteer recruitment brochure says that people with quadriplegia stemming from certain conditions “may qualify”.

Keyword: Robotics; Brain imaging
Link ID: 29163 - Posted: 02.25.2024

By Annie Melchor When the first known flying dinosaurs took to the skies some 150 million years ago, the evolutionary leap relied on adaptations to their nervous system. The changes remained a mystery, though, because of the paucity of fossilized neural tissue. Now fresh clues have emerged from a study that started with the long-gone dinosaurs’ living kin: the common pigeon, Columba livia. Flight taps neural pathways involving the pigeon’s cerebellum, the new works shows, which prompted study investigator Amy Balanoff and her team to look specifically at that structure in digital brain “endocasts,” created by CT scanning fossilized dinosaur skulls. “The birds can help us look for certain things within these extinct animals,” says Balanoff, assistant professor of evolutionary biology at Johns Hopkins University. “Then these extinct animals can tell us about the evolutionary history leading up to living birds.” An analysis of the endocasts — from 10 dinosaur specimens dating to between 90 and 150 million years ago — revealed that the volume of the cerebellum expanded in birds’ closest relatives, but not in more distant ones. And at some point, the cerebellum began folding — instead of growing — to accommodate more neurons within a fixed cranial space, Balanoff says. The results suggest that the cerebellum was “flight-ready before flying,” says Crístian Gutiérrez-Ibáñez, an evolutionary biology research associate at the University of Alberta who was not involved in the study. “So the question is, why did dinosaurs get such a big cerebellum?” © 2024 Simons Foundation

Keyword: Evolution; Movement Disorders
Link ID: 29162 - Posted: 02.25.2024

Fen-Biao Gao Around 55 million people worldwide suffer from dementia such as Alzheimer’s disease. On Feb. 22, 2024, it was revealed that former talk show host Wendy Williams had been diagnosed with frontotemporal dementia, or FTD, a rare type of dementia that typically affects people ages 45 to 64. Bruce Willis is another celebrity who was diagnosed with the syndrome, according to his family. In contrast to Alzheimer’s, in which the major initial symptom is memory loss, FTD typically involves changes in behavior. The initial symptoms of FTD may include changes in personality, behavior and language production. For instance, some FTD patients exhibit inappropriate social behavior, impulsivity and loss of empathy. Others struggle to find words and to express themselves. This insidious disease can be especially hard for families and loved ones to deal with. There is no cure for FTD, and there are no effective treatments. Up to 40% of FTD cases have some family history, which means a genetic cause may run in the family. Since researchers identified the first genetic mutations that cause FTD in 1998, more than a dozen genes have been linked to the disease. These discoveries provide an entry point to determine the mechanisms that underlie the dysfunction of neurons and neural circuits in the brain and to use that knowledge to explore potential approaches to treatment. I am a researcher who studies the development of FTD and related disorders, including the motor neuron disease amyotrophic lateral sclerosis, or ALS. ALS, also known as Lou Gehrig’s disease, results in progressive muscle weakness and death. Uncovering the similarities in pathology and genetics between FTD and ALS could lead to new ways to treat both diseases. Genes contain the instructions cells use to make the proteins that carry out functions essential to life. Mutated genes can result in mutated proteins that lose their normal function or become toxic. © 2010–2024, The Conversation US, Inc.

Keyword: Alzheimers; ALS-Lou Gehrig's Disease
Link ID: 29161 - Posted: 02.25.2024

David Robson Scientific discoveries can emerge from the strangest places. In early 1900s France, the doctor Albert Calmette and the veterinarian Camille Guérin aimed to discover how bovine tuberculosis was transmitted. To do so, they first had to find a way of cultivating the bacteria. Sliced potatoes – cooked with ox bile and glycerine – proved to be the perfect medium. As the bacteria grew, however, Calmette and Guérin were surprised to find that each generation lost some of its virulence. Animals infected with the microbe (grown through many generations of their culture) no longer became sick but were protected from wild TB. In 1921, the pair tested this potential vaccine on their first human patient – a baby whose mother had just died of the disease. It worked, and the result was the Bacille Calmette-Guérin (BCG) vaccine that has saved millions of lives. A black and white image pf Camille Guérin and physician Albert Calmette side by side. French veterinarian Camille Guérin and physician Albert Calmette developed the BCG jab in 1921 using sliced potatoes cooked with ox bile and glycerine. Photograph: Musée Pasteur Calmette and Guérin could have never imagined that their research would inspire scientists investigating an entirely different kind of disease more than a century later. Yet that is exactly what is happening, with a string of intriguing studies suggesting that BCG can protect people from developing Alzheimer’s disease. If these preliminary results bear out in clinical trials, it could be one of the cheapest and most effective weapons in our fight against dementia. According to the World Health Organization, 55 million people now have dementia, with about 10 million new cases each year. Alzheimer’s disease is by far the most common form, accounting for about 60%-70% of cases. It is characterised by clumps of a protein called amyloid beta that accumulate within the brain, killing neurons and destroying the synaptic connections between the cells. © 2024 Guardian News & Media Limited

Keyword: Alzheimers; Neuroimmunology
Link ID: 29160 - Posted: 02.25.2024

By Miryam Naddaf Moving a prosthetic arm. Controlling a speaking avatar. Typing at speed. These are all things that people with paralysis have learnt to do using brain–computer interfaces (BCIs) — implanted devices that are powered by thought alone. These devices capture neural activity using dozens to hundreds of electrodes embedded in the brain. A decoder system analyses the signals and translates them into commands. Although the main impetus behind the work is to help restore functions to people with paralysis, the technology also gives researchers a unique way to explore how the human brain is organized, and with greater resolution than most other methods. Scientists have used these opportunities to learn some basic lessons about the brain. Results are overturning assumptions about brain anatomy, for example, revealing that regions often have much fuzzier boundaries and job descriptions than was thought. Such studies are also helping researchers to work out how BCIs themselves affect the brain and, crucially, how to improve the devices. “BCIs in humans have given us a chance to record single-neuron activity for a lot of brain areas that nobody’s ever really been able to do in this way,” says Frank Willett, a neuroscientist at Stanford University in California who is working on a BCI for speech. The devices also allow measurements over much longer time spans than classical tools do, says Edward Chang, a neurosurgeon at the University of California, San Francisco. “BCIs are really pushing the limits, being able to record over not just days, weeks, but months, years at a time,” he says. “So you can study things like learning, you can study things like plasticity, you can learn tasks that require much, much more time to understand.” © 2024 Springer Nature Limited

Keyword: Brain imaging; Robotics
Link ID: 29159 - Posted: 02.22.2024

Nicola Davis Science correspondent From forgetfulness to difficulties concentrating, many people who have long Covid experience “brain fog”. Now researchers say the symptom could be down to the blood-brain barrier becoming leaky. The barrier controls which substances or materials enter and exit the brain. “It’s all about regulating a balance of material in blood compared to brain,” said Prof Matthew Campbell, co-author of the research at Trinity College Dublin. “If that is off balance then it can drive changes in neural function and if this happens in brain regions that allow for memory consolidation/storage then it can wreak havoc.” Writing in the journal Nature Neuroscience, Campbell and colleagues report how they analysed serum and plasma samples from 76 patients who were hospitalised with Covid in March or April 2020, as well 25 people before the pandemic. Among other findings, the team discovered that samples from the 14 Covid patients who self-reported brain fog contained higher levels of a protein called S100β than those from Covid patients without this symptom, or people who had not had Covid. caskets at a funeral home This protein is produced by cells within the brain, and is not normally found in the blood, suggesting these patients had a breakdown of the blood-brain barrier. The researchers then recruited 10 people who had recovered from Covid and 22 people with long Covid – 11 of whom reported having brain fog. None had, at that point, received a Covid vaccine, or been hospitalised for Covid. These participants underwent an MRI scan in which a dye was administered intravenously. The results reveal long Covid patients with brain fog did indeed show signs of a leaky blood-brain barrier, but not those without this symptom, or who had recovered. © 2024 Guardian News & Media Limited

Keyword: Neuroimmunology
Link ID: 29158 - Posted: 02.22.2024

By Pam Belluck Jennifer Caldwell was active and energetic, working two jobs and taking care of her daughter and her parents, when she developed a bacterial infection that was followed by intense lightheadedness, fatigue and memory problems. That was nearly a decade ago, and she has since struggled with the condition known as myalgic encephalomyelitis/chronic fatigue syndrome, or ME/CFS. Ms. Caldwell, 56, of Hillsborough, N.C., said she went from being able to ski, dance and work two jobs as a clinical research coordinator and a caterer to needing to stay in bed most of every day. “I haven’t been right since, and I haven’t worked a day since,” said Ms. Caldwell, whose symptoms include severe dizziness whenever her legs are not elevated. The condition has also “messed me up cognitively,” she said. “I can’t read something and comprehend it very well at all, I can’t remember new things. It’s kind of like being in a limbo state. That’s how I describe it, lost in limbo.” Seven years ago, the National Institutes of Health began a study of patients with ME/CFS, and Ms. Caldwell became one of 17 participants who engaged in a series of tests and evaluations of their blood, bodies and brains. Findings from the study, which was published on Wednesday in the journal Nature Communications, showed notable physiological differences in the immune system, cardio-respiratory function, gut microbiome and brain activity of the ME/CFS patients compared with a group of 21 healthy study participants. Medical experts said that even though the study was a snapshot of a small number of patients, it was valuable, partly because ME/CFS has long been dismissed or misdiagnosed. The findings confirm that “it’s biological, not psychological,” said Dr. Avindra Nath, the chief of infections of the nervous system at the National Institute of Neurological Disorders and Stroke, who led the study. © 2024 The New York Times Company

Keyword: Neuroimmunology; Depression
Link ID: 29157 - Posted: 02.22.2024

By Jackie Rocheleau Every day about 60,000 people have surgery under general anesthesia in the United States. Often casually compared to falling into a deep sleep, going under is in fact wildly different from your everyday nocturnal slumber. Not only does a person lose the ability to feel pain, form memories, or move—they can’t simply be nudged back into conscious awareness. But occasionally, people do wake unexpectedly—in about 1 out of every 1,000 to 2,000 surgeries, patients emerge from the fog of anesthesia into the harsh light of the operating room while still under the knife. One question that has dogged researchers over the past several decades is whether women are more likely to find themselves in these unfortunate circumstances. A number of recent studies, including a 2023 meta-analysis, suggest that the answer is yes. But the findings are controversial: Other studies have found no differences in waking frequency between the sexes and most of the studies were not designed specifically to identify sex differences. It’s also difficult to know whether other factors might have influenced the results: rates of metabolization of drugs by male and female bodies, as well as variation in kinds of surgeries and anesthetic regimens among study participants. No causal link had been established. Now, a new study published in the Proceedings of the National Academy of Sciences helps untangle some of the mystery. In a series of experiments in mice and in humans, the researchers found that females do wake more easily from anesthesia and that testosterone plays an important role in how quickly and deeply we go under, and how easily we wake up. “There seems to be something hardwired into the female brain that biases it more toward a state of wakefulness,” says University of Pennsylvania anesthesiologist Max Kelz, co-author of the study. © 2024 NautilusNext Inc., All rights reserved.

Keyword: Sexual Behavior; Sleep
Link ID: 29156 - Posted: 02.22.2024

By David Ovalle Keifer Geers was born with a hole in his diaphragm that led to painful surgeries in adulthood. Despite physical challenges that included deafness, Geers graduated from Texas A&M University with a degree in biomedical engineering. He hoped to one day create medical devices for disabled children and wounded veterans. On a spring day as Geers walked with his mother through an airport in Midland, Tex., he stumbled, then collapsed into a seizure, his face contorted in shock. Geers, 33, was pronounced dead at a hospital. His mother later found inside his suitcase several packages of powder kratom, an herbal product he consumed to manage pain from surgeries. Patricia Geers said she was stunned when an autopsy concluded that her son died from the toxic effects of kratom — levels in his blood were more than nine times what some experts believe can prove lethal. The death of Keifer Geers was hardly an isolated episode. A Washington Post review of federal and state statistics shows that medical examiners and coroners are increasingly blaming deaths on kratom — it was listed as contributing to or causing at least 4,100 deaths in 44 states and D.C. between 2020 and 2022. The vast majority of those cases involved other drugs in addition to kratom, which is made from the leaves of tropical trees. Still, the kratom-involved deaths account for a small fraction of the more than 300,000 U.S. overdose deaths recorded in those three years. Dozens of wrongful death lawsuits involving kratom have been filed nationwide — including by Geers’s mother, who in February sued a Nevada retailer. The suits illustrate increased scrutiny of deaths involving products made from kratom, which is banned in six states but remains widely available online and in vape and convenience stores despite health warnings from federal authorities.

Keyword: Drug Abuse
Link ID: 29155 - Posted: 02.22.2024

By Tina Hesman Saey One particular retrovirus — embedded in the DNA of jawed vertebrates — helps turn on production of a protein needed to insulate nerve fibers, researchers report February 15 in Cell. Such insulation, called myelin, may have helped make speedy thoughts and complex brains possible. The retrovirus trick was so handy, in fact, that it showed up many times in the evolution of vertebrates with jaws, the team found. Retroviruses — also known as jumping genes or retrotransposons — are RNA viruses that make DNA copies of themselves to embed in a host’s DNA. Scientists once thought of remnants of ancient viruses as genetic garbage, but that impression is changing, says neuroscientist Jason Shepherd, who was not involved in the study. “We’re finding more and more that these retrotransposons and retroviruses have influenced the evolution of life on the planet,” says Shepherd, of the University of Utah Spencer Fox Eccles School of Medicine in Salt Lake City. Remains of retroviruses were already known to have aided the evolution of the placenta, the immune system and other important milestones in human evolution (SN: 5/16/17). Now, they’re implicated in helping to produce myelin. Myelin is a coating of fat and protein that encases long nerve fibers known as axons. The coating works a bit like the insulation around an electrical wire: Nerves sheathed in myelin can send electrical signals faster than uninsulated nerves can. © Society for Science & the Public 2000–2024.

Keyword: Glia; Evolution
Link ID: 29154 - Posted: 02.20.2024

By Angie Voyles Askham The primary visual cortex carries, well, visual information — or so scientists thought until early 2010. That’s when a team at the University of California, San Francisco first described vagabond activity in the brain area, called V1, in mice. When the animals started to run on a treadmill, some neurons more than doubled their firing rate. The finding “was kind of mysterious,” because V1 was thought to represent only visual signals transmitted from the retina, says Anne Churchland, professor of neurobiology at the University of California, Los Angeles, who was not involved in that work. “The idea that running modulated neural activity suggested that maybe those visual signals were corrupted in a way that, at the time, felt like it would be really problematic.” The mystery grew over the next decade, as a flurry of mouse studies from Churchland and others built on the 2010 results. Both arousal and locomotion could shape the firing of primary visual neurons, those newer findings showed, and even subtle movements such as nose scratches contribute to variance in population activity, all without compromising the sensory information. A consensus started to form around the idea that sensory cortical regions encode broader information about an animal’s physiological state than previously thought. At least until last year, when two studies threw a wrench into that storyline: Neither marmosets nor macaque monkeys show any movement-related increase in V1 signaling. Instead, running seems to slightly suppress V1 activity in marmosets, and spontaneous movements have no effect on the same cells in macaques. The apparent differences across species raise new questions about whether mice are a suitable model to study the primate visual system, says Michael Stryker, professor of physiology at the University of California, San Francisco, who led the 2010 work. “Maybe the primate’s V1 is not working the same as in the mouse,” he says. “As I see it, it’s still a big unanswered question.” © 2024 Simons Foundation

Keyword: Vision
Link ID: 29153 - Posted: 02.20.2024

By Matt Richtel Growing numbers of children and adolescents are being prescribed multiple psychiatric drugs to take simultaneously, according to a new study by researchers at the University of Maryland. The phenomenon is increasing despite warnings that psychotropic drug combinations in young people have not been tested for safety or studied for their impact on the developing brain. The study, published Friday in JAMA Open Network, looked at the prescribing patterns among patients 17 or younger enrolled in Medicaid from 2015 to 2020 in a single U.S. state that the researchers declined to name. In this group, there was a 9.5 percent increase in the prevalence of “polypharmacy,” which the study defined as taking three or more different classes of psychiatric medications, including antidepressants, mood-stabilizing anticonvulsants, sedatives and drugs for A.D.H.D. and anxiety drugs. The study looked at only one state, but state data have been used in the past to explore this issue, in part because of the relative ease of gathering data from Medicaid, the health insurance program administered by states. At the same time, some research using nationally weighted samples have revealed the increasing prevalence of polypharmacy among young people. One recent paper drew data from the National Ambulatory Medical Care Survey and found that in 2015, 40.7 percent of people aged 2 to 24 in the United States who took a medication for A.D.H.D. also took a second psychiatric drug. That figure had risen from 26 percent in 2006. The latest data from the University of Maryland researchers show that, at least in one state, the practice continues to grow and “was significantly more likely among youths who were disabled or in foster care,” the new study noted. Mental health experts said that psychotropic medications can prove very helpful and that doctors have discretion to prescribe what they see fit. A concern among some experts is that many drugs used in frequently prescribed cocktails have not been approved for use in young people. And it is unclear how the simultaneous use of multiple psychotropic medications affects brain development long-term. © 2024 The New York Times Company

Keyword: Depression; Development of the Brain
Link ID: 29152 - Posted: 02.20.2024

Nancy S. Jecker & Andrew Ko Putting a computer inside someone’s brain used to feel like the edge of science fiction. Today, it’s a reality. Academic and commercial groups are testing “brain-computer interface” devices to enable people with disabilities to function more independently. Yet Elon Musk’s company, Neuralink, has put this technology front and center in debates about safety, ethics and neuroscience. In January 2024, Musk announced that Neuralink implanted its first chip in a human subject’s brain. The Conversation reached out to two scholars at the University of Washington School of Medicine – Nancy Jecker, a bioethicst, and Andrew Ko, a neurosurgeon who implants brain chip devices – for their thoughts on the ethics of this new horizon in neuroscience. How does a brain chip work? Neuralink’s coin-size device, called N1, is designed to enable patients to carry out actions just by concentrating on them, without moving their bodies. Subjects in the company’s PRIME study – short for Precise Robotically Implanted Brain-Computer Interface – undergo surgery to place the device in a part of the brain that controls movement. The chip records and processes the brain’s electrical activity, then transmits this data to an external device, such as a phone or computer. The external device “decodes” the patient’s brain activity, learning to associate certain patterns with the patient’s goal: moving a computer cursor up a screen, for example. Over time, the software can recognize a pattern of neural firing that consistently occurs while the participant is imagining that task, and then execute the task for the person. © 2010–2024, The Conversation US, Inc.

Keyword: Robotics; Learning & Memory
Link ID: 29151 - Posted: 02.20.2024

By Erin Garcia de Jesús DENVER — A weight-loss drug used to treat obesity and diabetes has shown promise to treat another disorder: opioid addiction. Early results from a small clinical trial, presented February 17 at the annual meeting of the American Association for the Advancement of Science, suggest that a close relative of the weight-loss drugs Wegovy and Ozempic significantly lessened cravings for opioids in people with opioid use disorder. “For them to have any time when they might be free of that craving seems to be very hopeful,” Patricia “Sue” Grigson, a behavioral neuroscientist at Penn State College of Medicine in Hershey said at the conference. The vast majority of drug overdose deaths in the United States are due to opioids (SN: 2/14/24). The drug, called liraglutide, mimics a hormone called GLP-1 that the body releases after people eat. Wegovy and Ozempic — brand names for semaglutide, a molecule that induces weight loss more effectively than liraglutide — also imitate the hormone. It’s unclear exactly how the drugs work when it comes to weight loss, but researchers think such GLP-1 dupes prompt the body and brain to make people feel full (SN: 12/13/23). There are hints that such drugs could work for addiction, too. People taking Wegovy or Ozempic have reported lessened desire for not just food but also alcohol and nicotine. What’s more, Grigson and colleagues showed in a previous study in rats that liraglutide can cut down on heroin-seeking behavior, perhaps by changing the animals’ brain activity (SN: 8/30/23). © Society for Science & the Public 2000–2024.

Keyword: Drug Abuse; Obesity
Link ID: 29150 - Posted: 02.20.2024

By Christine Dell'Amore Thunderclouds rolled across Kenya’s Masai Mara savanna as the spotted hyena cubs played, tumbling over each other in the wet grass. The cubs’ mother lounged nearby, rising occasionally to discourage a bigger one-year-old from joining the little play group. When the older animal approached again, one of the pluckier cubs took a cue from its high-ranking mom and stood tall, trying its best to look intimidating. That action seemed comical, but both animals knew their place. The larger, lower ranking hyena stopped short, then bowed its head and slunk off. Photographer Jen Guyton recorded this scene with an infrared camera, allowing an intimate look into hyenas’ nocturnal behaviors. In doing so, she provided a small window into the intriguing structure of hyena society, where all members inherit their place in the pecking order from their mother. Females are in charge, and rank means everything—a matrilineal system that has fueled the spotted hyena’s rise as the most abundant large carnivore in Africa. These and other insights into hyena behavior wouldn’t be possible were it not for 35 years of on-the-ground research by Kay Holekamp, founder of the Mara Hyena Project. Her efforts have helped reveal a creature noted for its advanced society, cognition, and ability to adjust to new surroundings. Holekamp, a biologist at Michigan State University, has been studying the African species in the Masai Mara since 1988—one of the longest running investigations of any mammal ever. “I thought I’d be there for two years,” she says, “but I got hooked.” Hooked on hyenas? Mention their name, and most people grimace. Aristotle described them as “exceedingly fond of putrefied flesh.” Theodore Roosevelt called them a “singular mixture of abject cowardice and the utmost ferocity.” Across Africa, hyenas are seen as evil, greedy, and associated with witchcraft and sexual deviance. Even the 1994 movie The Lion King portrayed them as cunning and malicious. © 1996-2015 National Geographic Society

Keyword: Sexual Behavior; Evolution
Link ID: 29149 - Posted: 02.13.2024

By Kevin Mitchell It is often said that “the mind is what the brain does.” Modern neuroscience has indeed shown us that mental goings-on rely on and are in some sense entailed by neural goings-on. But the truth is that we have a poor handle on the nature of that relationship. One way to bridge that divide is to try to define the relationship between neural and mental representations. The basic premise of neuroscience is that patterns of neural activity carry some information — they are about something. But not all such patterns need be thought of as representations; many of them are just signals. Simple circuits such as the muscle stretch reflex or the eye-blink reflex, for example, are configured to respond to stimuli such as the lengthening of a muscle or a sudden bright light. But they don’t need to internally represent this information — or make that information available to other parts of the nervous system. They just need to respond to it. More complex information processing, by contrast, such as in our image-forming visual system, requires internal neural representation. By integrating signals from multiple photoreceptors, retinal ganglion cells carry information about patterns of light in the visual stimulus — particularly edges where the illumination changes from light to dark. This information is then made available to the thalamus and the cortical hierarchy, where additional processing goes on to extract higher- and higher-order features of the entire visual scene. Scientists have elucidated the logic of these hierarchical systems by studying the types of stimuli to which neurons are most sensitively tuned, known as “receptive fields.” If some neuron in an early cortical area responds selectively to, say, a vertical line in a certain part of the visual field, the inference is that when such a neuron is active, that is the information that it is representing. In this case, it is making that information available to the next level of the visual system — itself just a subsystem of the brain. © 2024 Simons Foundation

Keyword: Consciousness; Vision
Link ID: 29148 - Posted: 02.13.2024

Rob Stein Benjamin Franklin famously wrote: "In this world nothing can be said to be certain, except death and taxes." While that may still be true, there's a controversy simmering today about one of the ways doctors declare people to be dead. The debate is focused on the Uniform Determination of Death Act, a law that was adopted by most states in the 1980s. The law says that death can be declared if someone has experienced "irreversible cessation of all functions of the entire brain." But some parts of the brain can continue to function in people who have been declared brain dead, prompting calls to revise the statute. Many experts say the discrepancy needs to be resolved to protect patients and their families, maintain public trust and reconcile what some see as a troubling disconnect between the law and medical practice. The debate became so contentious, however, that the Uniform Law Commission, the group charged with rewriting model laws for states, paused its process last summer because participants couldn't reach a consensus. "I'm worried," says Thaddeus Pope, a bioethicist and lawyer at Mitchell Hamline School of Law in St. Paul, Minnesota. "There's a lot of conflict at the bedside over this at hospitals across the United States. Let's get in front of it and fix it before it becomes a crisis. It's such an important question that everyone needs to be on the same page." The second method, brain death, can be declared for people who have sustained catastrophic brain injury causing the permanent cessation of all brain function, such as from a massive traumatic brain injury or massive stroke, but whose hearts are still pumping through the use of ventilators or other artificial forms of life support. © 2024 npr

Keyword: Brain Injury/Concussion; Brain imaging
Link ID: 29147 - Posted: 02.13.2024

By Miryam Naddaf An analysis of around 1,500 blood proteins has identified biomarkers that can be used to predict the risk of developing dementia up to 15 years before diagnosis. The findings, reported today in Nature Aging1, are a step towards a tool that scientists have been in search of for decades: blood tests that can detect Alzheimer’s disease and other forms of dementia at a very early, pre-symptomatic stage. Researchers screened blood samples from more than 50,000 healthy adults in the UK Biobank, 1,417 of whom developed dementia in a 14-year period. They found that high blood levels of four proteins — GFAP, NEFL, GDF15 and LTBP2 — were strongly associated with dementia. “Studies such as this are required if we are to intervene with disease-modifying therapies at the very earliest stage of dementia,” said Amanda Heslegrave, a neuroscientist at University College London, in a statement to the Science Media Centre in London. According to the World Health Organization, more than 55 million people worldwide currently live with dementia. People are often diagnosed only when they notice memory problems or other symptoms. At that point, the disease might have been progressing for years. “Once we diagnose it, it’s almost too late,” says study co-author Jian-Feng Feng, a computational biologist at Fudan University in Shanghai, China. “And it’s impossible to reverse it.” By screening 1,463 proteins in blood samples from 52,645 people, the authors found that increased levels of GFAP, NEFL, GDF15 and LTBP2 were associated with dementia and Alzheimer’s disease. For some participants who developed dementia, blood levels of these proteins were outside normal ranges more than ten years before symptom onset. © 2024 Springer Nature Limited

Keyword: Alzheimers
Link ID: 29146 - Posted: 02.13.2024

By Claudia López Lloreda By squirting cells from a 3D printer, researchers have created tissue that looks—and acts—like a chunk of brain. In recent years, scientists have learned how to load up 3D printers with cells and other scaffolding ingredients to create living tissues, but making realistic brainlike constructs has been a challenge. Now, one team has shown that, by modifying its printing techniques, it can print and combine multiple subtypes of cells that better mimic signaling in the human brain. “It’s remarkable that [the researchers] can replicate” how brain cells work, says Riccardo Levato, a regenerative medicine researcher at Utrecht University who was not involved with the study. “It’s the first demonstration that, with some simple organization [of cells], you can start getting some interesting functional [responses].” The new technology, described last week in Cell Stem Cell, could offer advantages over existing techniques that neuroscientists use to create 3D brain tissues in the lab. One common approach involves using stem cells to grow miniature brainlike blobs called organoids. But researchers can’t control the types of cells or their precise location in these constructs. Each organoid “is unique,” making it difficult to reproduce research results, says neuroscientist Su-Chun Zhang of the University of Wisconsin–Madison, an author of the new study. With the right kind of 3D printing, however, “you can control where different cell types are placed,” says developmental biologist Francis Szele of the University of Oxford. Past studies have used 3D printers to construct brain tissues that allowed researchers to study how the cells matured and made connections, and even integrate printed tissue into mouse brains. But those constructs had limited functionality. And efforts that produced more functional printed tissue used rat cells, not human cells. © 2024 American Association for the Advancement of Science.

Keyword: Development of the Brain; Robotics
Link ID: 29145 - Posted: 02.10.2024

By Simon Makin A new device makes it possible for a person with an amputation to sense temperature with a prosthetic hand. The technology is a step toward prosthetic limbs that restore a full range of senses, improving both their usefulness and acceptance by those who wear them. A team of researchers in Italy and Switzerland attached the device, called ”MiniTouch,” to the prosthetic hand of a 57-year-old man named Fabrizio, who has an above-the-wrist amputation. In tests, the man could identify cold, cool and hot bottles of liquid with perfect accuracy; tell the difference between plastic, glass and copper significantly better than chance; and sort steel blocks by temperature with around 75 percent accuracy, researchers report February 9 in Med. Thank you for being a subscriber to Science News! Interested in more ways to support STEM? Consider making a gift to our nonprofit publisher, Society for Science, an organization dedicated to expanding scientific literacy and ensuring that every young person can strive to become an engineer or scientist. “It’s important to incorporate these technologies in a way that prosthesis users can actually use to perform functional tasks,” says neuroengineer Luke Osborn of Johns Hopkins University Applied Physics Laboratory in Laurel, Md., who was not involved in the study. “Introducing new sensory feedback modalities could help give users more functionality they weren’t able to achieve before.” The device also improved Fabrizio’s ability to tell whether he was touching an artificial or human arm. His accuracy was 80 percent with the device turned on, compared with 60 percent with it off. “It’s not quite as good as with the intact hand, probably because we’re not giving [information about] skin textures,” says neuroengineer Solaiman Shokur of EPFL, the Swiss Federal Institute of Technology in Lausanne. © Society for Science & the Public 2000–2024.

Keyword: Pain & Touch
Link ID: 29144 - Posted: 02.10.2024