By Lisa Sanders, M.D. The 62-year-old woman shifted in her seat. The flight to Honolulu was full, the mood a little giddy. The unbroken ocean and sky filled the window. She and her daughter were four hours into the trip from Los Angeles to the wedding of a close family friend; it was going to be a great week. Then, she caught herself scratching lightly at a place on her forearm, just below the crease of her elbow. She lifted her arm to look at the spot. Nothing there. Immediately she was filled with dread. She reached over her head to touch the call button. She needed ice, lots of ice, and she needed it right away. The mild itch had already exploded into spasms of an intense sensation — it seemed wrong to call it an itch; surely there was a better word for it. The fierce intensity of the feeling shocked her. It was a feeling that insisted she scratch. Except scratching never helped. And she had the scars to prove it. She had suffered episodes of itching like this a few times in the past couple of years, though never quite as bad as it was on this flight. Her doctor back home had no idea what caused the crazy itch or what more she might do about it. These attacks came out of nowhere but immediately brought life to a standstill as she tried to ease the unbearable sensation. A bout could last for hours and almost always ended with her arm a bloody mess. When her daughter first saw her mother raking her nails over the invisible injury and the distress she felt fighting this unwinnable battle, she had offered her a Valium. And it helped. The itch was still there but the intensity somehow lessened. On the flight, the woman retrieved the pills she now carried with her all the time. The little bags of ice brought by the flight attendant melted slowly, numbing the hand that pressed them against her arm and easing the itch. She knew from experience that as soon as the ice was removed, the itch would roar back. The attendant brought an ice bucket. But within the hour, she needed more ice. More Valium. She was drenched with the condensation. Her clothes were dotted with blood. She didn’t care. She just had to get through it. © 2024 The New York Times Company

Keyword: Pain & Touch
Link ID: 29583 - Posted: 12.04.2024

Heather Margonari The opioid crisis remains a significant public health challenge in the United States. In 2022, over 2.5 million American adults had an opioid use disorder, and opioids accounted for nearly 76% of overdose deaths. Some patients are fearful of using opioids after surgery due to concerns about dependence and potential side effects, even when appropriately prescribed by a doctor to manage pain. Surgery is often the first time patients receive an opioid prescription, and their widespread use raises concerns about patients becoming long-term users. Leftover pills from a patient’s prescriptions may also be misused. Researchers like us are working to develop a personalized and comprehensive surgical experience that doesn’t use opioids. Our approach to opioid-free surgery addresses both physical and emotional well-being through effective anesthesia and complementary pain-management techniques. What is opioid-free anesthesia? Clinicians have used morphine and other opioids to manage pain for thousands of years. These drugs remain integral to anesthesia. Help us raise up the voices of experts. Most surgical procedures use a strategy called balanced anesthesia, which combines drugs that induce sleep and relax muscles with opioids to control pain. However, using opioids in anesthesia can lead to unwanted side effects, such as serious cardiac and respiratory problems, nausea and vomiting, and digestive issues. Concerns over these adverse effects and the opioid crisis have fueled the development of opioid-free anesthesia. This approach uses non-opioid drugs to relieve pain before, during and after surgery while minimizing the risk of side effects and dependency. Studies have shown that opioid-free anesthesia can provide similar levels of pain relief to traditional methods using opioids. Copyright © 2010–2024, The Conversation US, Inc.

Keyword: Pain & Touch
Link ID: 29575 - Posted: 11.27.2024

By Fred Schwaller Scott Imbrie still remembers the first time that physicians switched on the electrodes sitting on the surface of his brain. He felt a tingling, poking sensation in his hand, like “reaching into an evergreen bush”, he says. “It was like I was decorating a Christmas tree.” Back in 1985, a car crash shattered three of Imbrie’s vertebrae and severed 70% of his spinal cord, leaving him with very limited sensation or mobility in parts of his body. Now, thanks to an implanted brain–computer interface (BCI), Imbrie can operate a robotic arm, and receive sensory information related to what that arm is doing. Imbrie spends four days a week, three hours at a time, testing, refining and tuning the device with a team of researchers at the University of Chicago in Illinois. Scientists have been trying to restore mobility for people with missing or paralysed limbs for decades. The aim, historically, was to give people the ability to control prosthetics with commands from the nervous system. But this motor-first approach produced bionic limbs that were much less helpful than hoped: devices were cumbersome and provided only rudimentary control of a hand or leg. What’s more, they just didn’t feel like they were part of the body and required too much concentration to use. Scientists gradually began to realize that restoring full mobility meant restoring the ability to sense touch and temperature, says Robert Gaunt, a bioengineer at the University of Pittsburgh in Pennsylvania. Gaunt says that this realization has led to a revolution in the field. A landmark study1 came in 2016, when a team led by Gaunt restored tactile sensations in a person with upper-limb paralysis using a computer chip implanted in a region of the brain that controls the hand. Gaunt then teamed up with his Pittsburgh colleague, bioengineer Jennifer Collinger, to integrate a robotic arm with the BCI, allowing the individual to feel and manipulate objects. © 2024 Springer Nature Limited

Keyword: Robotics; Pain & Touch
Link ID: 29557 - Posted: 11.13.2024

Terry Gross We've all had bug bites, or dry scalp, or a sunburn that causes itch. But what if you felt itchy all the time — and there was no relief? Journalist Annie Lowrey suffers from primary biliary cholangitis (PBC), a degenerative liver disease in which the body mistakenly attacks cells lining the bile ducts, causing them to inflame. The result is a severe itch that doesn't respond to antihistamines or steroids. "It feels like being trapped inside your own body," Lowrey says of the disease. "I always describe it as being like a car alarm. Like, you can't stop thinking about it." PBC is impacts approximately 80,000 people in the U.S., the majority of whom are women. At its worst, Lowrey says, the itch caused her to dig holes in her skin and scalp. She's even fantasized about having limbs amputated to escape the itch. Lowrey writes about living with PBC in the Atlantic article, "Why People Itch and How to Stop It." She says a big part of her struggle is coming to terms with the fact that she may never feel fully at ease in her skin. "I talked to two folks who are a lot older than I was, just about like, how do you deal with it? How do you deal with the fact that you might itch and never stop itching? … And both of them were kind of like, 'You put up with it, stop worrying about it and get on with your life,'" she says. "I think I was mentally trapped ... and sometimes it's like, OK, ... go do something else. Life continues on. You have a body. It's OK." © 2024 npr

Keyword: Pain & Touch
Link ID: 29556 - Posted: 11.13.2024

By Erin Garcia de Jesús The first detailed structure of an infectious prion that causes chronic wasting disease, or CWD, reveals features that could help guide vaccine development or explain why the illness hasn’t yet made the leap to people, researchers report October 24 in Acta Neuropathologica. One such feature is a 180-degree twist between two sections of the prion. In versions engineered to infect rodents in order to study the disease, that twist doesn’t exist. Like the prion illness Creutzfeldt-Jakob disease in people, CWD prions in deer, elk and moose transform a healthy brain protein called PrP into misshapen versions that clump together and cause symptoms such as listlessness, drastic weight loss and lack of fear. While no person has contracted the disease and studies in mice and primates suggest that the risk to humans is extremely low, CWD’s spread among animals that people eat has raised concerns that it one day could jump to people (SN: 6/10/24). Understanding how deer prions misfold could help reveal why CWD doesn’t easily spread to humans. But “prions are messy,” says Byron Caughey, a biochemist at the National Institutes of Health’s Rocky Mountain Laboratories in Hamilton, Mont. Because the proteins “are very sticky and they tend to cling together,” researchers have a tough time getting a clear picture of what diseased prions look like. Previous studies looking at other prions, including rodent-adapted versions originally from sheep, showed that the proteins stack together like plates. Using hundreds of thousands of electron microscopy images, Caughey and colleagues found that a natural prion from the brain tissue of a white-tailed deer stacks in a similar way, but with some potentially key differences. © Society for Science & the Public 2000–2024.

Keyword: Prions
Link ID: 29552 - Posted: 11.13.2024

By Miryam Naddaf When a dog shakes water off its fur, the action is not just a random flurry of movements — nor a deliberate effort to drench anyone standing nearby. This instinctive reflex is shared by many furry mammals including mice, cats, squirrels, lions, tigers and bears. The move helps animals to remove water, insects or other irritants from hard-to-reach places. But underlying the shakes is a complex — and previously mysterious — neurological mechanism. Now, researchers have identified the neural circuit that triggers characteristic ‘wet dog’ shaking behaviour in mice — which involves a specific class of touch receptors, and neurons that connect the spinal cord to the brain. Their findings were published in Science on 7 November1. “The touch system is so complex and rich that [it] can distinguish a water droplet from a crawling insect from the gentle touch of a loved one,” says Kara Marshall, a neuroscientist at Baylor College of Medicine in Houston, Texas. “It’s really remarkable to be able to link a very specific subset of touch receptors to this familiar and understandable behaviour.” The hairy skin of mammals is packed with more than 12 types of sensory neuron, each with a unique function to detect and interpret various sensations. Study co-author Dawei Zhang, a neuroscientist then at Harvard Medical School in Boston, Massachusetts, and his colleagues focused on a type of ultra-sensitive touch detecting receptors called C-fibre low-threshold mechanoreceptors (C-LTMRs), which wrap around hair follicles. In humans, these receptors are associated with pleasant touch sensations, such as a soft hug or a soothing stroke. But in mice and other animals, they serve a protective role: alerting them to the presence of something on their skin, whether it’s water, dirt or a parasite. When these stimuli cause hairs on the skin to bend it activates the C-LTMRs, says Marshall, “extending the sensibility of the skin beyond just the surface”. © 2024 Springer Nature Limited

Keyword: Pain & Touch; Evolution
Link ID: 29551 - Posted: 11.09.2024

By Amber Dance For Cherise Irons, chocolate, red wine and aged cheeses are dangerous. So are certain sounds, perfumes and other strong scents, cold weather and thunderstorms. Stress and lack of sleep, too. She suspects all of these things can trigger her migraine attacks, which manifest in a variety of ways: pounding pain in the back of her head, exquisite sensitivity to the slightest sound, even blackouts and partial paralysis. Irons, 48, of Coral Springs, Florida, once worked as a school assistant principal. Now, she’s on disability due to her migraine. Irons has tried so many migraine medications she’s lost count — but none has helped for long. Even a few of the much-touted new drugs that have quelled episodes for many people with migraine have failed for Irons. Though not all are as impaired as Irons, migraine is a surprisingly common problem, affecting 14 percent to 15 percent of people. Yet scientists and physicians remain largely in the dark about how triggers like Irons’s lead to attacks. They have made progress nonetheless: The latest drugs, inhibitors of a body signaling molecule called CGRP, have been a blessing for many. For others, not so much. And it’s not clear why. The complexity of migraine probably has something to do with it. “It’s a very diverse condition,” says Debbie Hay, a pharmacologist at the University of Otago in Dunedin, New Zealand. “There’s still huge debate as to what the causes are, what the consequences are.”

Keyword: Pain & Touch
Link ID: 29519 - Posted: 10.16.2024

By Laura Sanders CHICAGO — Big news for fighting sisters: Scientists have found the sensors that signal the painful zing of a hair pull. And this pain message can rip along a nerve fiber at about 100 miles an hour, placing it among the fastest known pain signals. The discovery, presented October 8 at the annual meeting of the Society for Neuroscience, offers insight into the diverse ways our bodies sense and respond to different sorts of pain. Pain can come from many catastrophes — cuts, jabs, pinches, cramps, bites, slaps, stubbing a toe in the dark. And while our bodies can generally tell these insults apart thanks to a variety of biological pathways, they all hurt. “It’s not surprising that we have figured out many, many ways to make [pain] happen,” says neuroscientist Gregory Dussor of the University of Texas at Dallas. “Because when it doesn’t, we don’t live.” Laboratory tests showed a hair pull to be about 10 times as painful as a pinprick, neuroscientist Emma Kindström of Linköping University in Sweden and colleagues found. The pain of the pull relies on a large, propeller-shaped protein called PIEZO2, further tests showed. That sensor was known to detect mechanical forces, including light touches, but wasn’t thought to detect acute pain signals. People who lack this protein don’t feel hair-pull pain. A hair-pull signal moves along nerve fibers much faster than other sorts of pain, Kindström says, traveling in bursts along an insulated conduit called an Aβ nerve fiber. Other kinds of pain signals, such as a burn from a hot stove, travel more slowly along different kinds of fibers. © Society for Science & the Public 2000–2024.

Keyword: Pain & Touch
Link ID: 29512 - Posted: 10.12.2024

By Simon Makin The word “bionic” conjures sci-fi visions of humans enhanced to superhuman levels. It’s true that engineering advances such as better motors and batteries, together with modern computing, mean that the required mechanical and electronic systems are no longer a barrier to advanced prostheses. But the field has struggled to integrate these powerful machines with the human body. That’s starting to change. A recent trial tested one new integration technique, which involves surgically reconstructing muscle pairs that give recipients a sense of the position and movement of a bionic limb. Signals from those muscles control robotic joints, so the prosthesis is fully under control of the user’s brain. The system enabled people with below-knee amputations to walk more naturally and better navigate slopes, stairs and obstacles, researchers reported in the July Nature Medicine. Engineers have typically viewed biology as a fixed limitation to be engineered around, says bioengineer Tyler Clites, who helped develop the technique several years ago while at MIT. “But if we look at the body as part of the system to be engineered, in parallel with the machine, the two will be able to interact better.” That view is driving a wave of techniques that reengineer the body to better integrate with the machine. Clites, now at UCLA, calls such techniques “anatomics,” to distinguish them from traditional bionics. “The issue we were tackling wasn’t an engineering problem,” he says. “The way the body had been manipulated during the amputation wasn’t leaving it in a position to be able to control the limbs we were creating.” In an anatomics approach, bones are exploited to provide stable anchors; nerves are rerouted to create control signals for robotic limbs or transmit sensory feedback; muscles are co-opted as biological amplifiers or grafted into place to provide more signal sources. © Society for Science & the Public 2000–2024.

Keyword: Robotics
Link ID: 29507 - Posted: 10.05.2024

By Cassandra Willyard Megan Hodge’s first bout of intense pain arrived when she was in her mid-20s. Hodge and her husband were getting ready to visit family for Thanksgiving. Though Hodge had been dealing with a variety of chronic health issues, her workout had gone well that morning and she finally felt like she was getting a handle on her health. Hodge began packing. As she reached into her closet to grab a sweater, her back gave out. The pain was excruciating, so intense that she felt light-headed and thought she might vomit. As the years passed, Hodge had more frequent and more severe bouts of back pain. Any small movement could be a trigger — grabbing a towel from the linen closet, picking up a toy off the floor, sneezing. In 2021, Hodge experienced a particularly bad flare-up. None of the strategies she had previously used to help her manage seemed to be working. She was afraid to make any movement. She felt hopeless. “I just could not regain footing, metaphorically and physically,” she says. “I truly felt frozen in my chronic pain and chronic health journey.” Hodge is far from alone. In the United States, chronic pain affects tens of millions of people — about 1 in 5 adults and nearly 1 in 3 people ages 65 and older. “The amount of suffering from arthritis and aging that I’ve seen in my pain clinic, it’s overwhelming to me as a pain doctor,” says Antje Barreveld, an anesthesiologist at Mass General Brigham’s Newton-Wellesley Hospital in Massachusetts. What’s more, the mainstay therapy for severe acute and chronic pain — prescription opioids — has helped fuel an epidemic that kills tens of thousands of people each year. “We have to have some better alternatives,” she says. So researchers have doubled down in their quest to find new pain treatments that aren’t as addictive as opioids. “The pain field has really made very rapid and tremendous progress in the last decade,” says D.P. Mohapatra, a former pain scientist who now oversees research at the National Institute of Neurological Disorders and Stroke in Bethesda, Md. © Society for Science & the Public 2000–2024.

Keyword: Pain & Touch; Drug Abuse
Link ID: 29470 - Posted: 09.07.2024

By Pam Belluck When Shawn Connolly was diagnosed with Parkinson’s disease nine years ago, he was a 39-year-old daredevil on a skateboard, flipping and leaping from walls, benches and dumpsters through the streets of San Francisco. He appeared in videos and magazines, and had sponsorships from skateboard makers and shops. But gradually, he began to notice that “things weren’t really working right” with his body. He found that his right hand was cupping, and he began cradling his arm to hold it in place. His balance and alignment started to seem off. Over time, he developed a common Parkinson’s pattern, fluctuating between periods of rapid involuntary movements like “I’ve got ants in my pants” and periods of calcified slowness when, he said, “I could barely move.” A couple of years ago, Mr. Connolly volunteered for an experiment that summoned his daring and determination in a different way. He became a participant in a study exploring an innovative approach to deep brain stimulation. In the study, which was published Monday in the journal Nature Medicine, researchers transformed deep brain stimulation — an established treatment for Parkinson’s — into a personalized therapy that tailored the amount of electrical stimulation to each patient’s individual symptoms. The researchers found that for Mr. Connolly and the three other participants, the individualized approach, called adaptive deep brain stimulation, cut in half the time they experienced their most bothersome symptom. Mr. Connolly, now 48 and still skateboarding as much as his symptoms allow, said he noticed the difference “instantly.” He said the personalization gave him longer stretches of “feeling good and having that get-up-and-go.” © 2024 The New York Times Company

Keyword: Parkinsons
Link ID: 29447 - Posted: 08.21.2024

By Marla Broadfoot When doctors ask Sara Gehrig to describe her pain, she often says it is indescribable. Stabbing, burning, aching—those words frequently fail to depict sensations that have persisted for so long they are now a part of her, like her bones and skin. “My pain is like an extra limb that comes along with me every day.” Gehrig, a former yoga instructor and personal trainer who lives in Wisconsin, is 44 years old. At the age of 17 she discovered she had spinal stenosis, a narrowing of the spinal cord that puts pressure on the nerves there. She experienced bursts of excruciating pain in her back and buttocks and running down her legs. That pain has spread over the years, despite attempts to fend it off with physical therapy, anti-inflammatory injections and multiple surgeries. Over-the-counter medications such as ibuprofen (Advil) provide little relief. And she is allergic to the most potent painkillers—prescription opioids—which can induce violent vomiting. Today her agony typically hovers at a 7 out of 10 on the standard numerical scale used to rate pain, where 0 is no pain and 10 is the most severe imaginable. Occasionally her pain flares to a 9 or 10. At one point, before her doctor convinced her to take antidepressants, Gehrig struggled with thoughts of suicide. “For many with chronic pain, it’s always in their back pocket,” she says. “It’s not that we want to die. We want the pain to go away.” Gehrig says she would be willing to try another type of painkiller, but only if she knew it was safe. She keeps up with the latest research, so she was interested to hear earlier this year that Vertex Pharmaceuticals was testing a new drug that works differently than opioids and other pain medications. That drug, a pill called VX-548, blocks pain signals before they can reach the brain. It gums up sodium channels in peripheral nerve cells, and obstructed channels make it hard for those cells to transmit pain sensations. Because the drug acts only on the peripheral nerves, it does not carry the potential for addiction associated with opioids—oxycodone (OxyContin) and similar drugs exert their effects on the brain and spinal cord and thus can trigger the brain’s reward centers and an addiction cycle.

Keyword: Pain & Touch; Drug Abuse
Link ID: 29445 - Posted: 08.21.2024

Julia Kollewe Oran Knowlson, a British teenager with a severe type of epilepsy called Lennox-Gastaut syndrome, became the first person in the world to trial a new brain implant last October, with phenomenal results – his daytime seizures were reduced by 80%. “It’s had a huge impact on his life and has prevented him from having the falls and injuring himself that he was having before,” says Martin Tisdall, a consultant paediatric neurosurgeon at Great Ormond Street Hospital (Gosh) in London, who implanted the device. “His mother was talking about how he’s had such a improvement in his quality of life, but also in his cognition: he’s more alert and more engaged.” Oran’s neurostimulator sits under the skull and sends constant electrical signals deep into his brain with the aim of blocking abnormal impulses that trigger seizures. The implant, called a Picostim and about the size of a mobile phone battery, is recharged via headphones and operates differently between day and night. The video player is currently playing an ad. You can skip the ad in 5 sec with a mouse or keyboard “The device has the ability to record from the brain, to measure brain activity, and that allows us to think about ways in which we could use that information to improve the efficacy of the stimulation that the kids are getting,” says Tisdall. “What we really want to do is to deliver this treatment on the NHS.” As part of a pilot, three more children with Lennox-Gastaut syndrome will be fitted with the implant in the coming weeks, followed by a full trial with 22 children early next year. If this goes well, the academic sponsors – Gosh and University College London – will apply for regulatory approval. Tim Denison – a professor of engineering science at Oxford University and co-founder and chief engineer of London-based Amber Therapeutics, which developed the implant with the university – hopes the device will be available on the NHS in four to five years’ time, and around the world. © 2024 Guardian News & Media Limite

Keyword: Robotics; Epilepsy
Link ID: 29442 - Posted: 08.19.2024

By Sara Talpos Nervous system disorders are among the leading causes of death and disability globally. Conditions such as paralysis and aphasia, which affects the ability to understand and produce language, can be devastating to patients and families. Significant investment has been put toward brain research, including the development of new technologies to treat some conditions, said Saskia Hendriks, a bioethicist at the U.S. National Institutes of Health. These technologies may very well improve lives, but they also raise a host of ethical issues. That’s in part because of the unique nature of the brain, said Hendriks. It’s “the seat of many functions that we think are really important to ourselves, like consciousness, thoughts, memories, emotions, perceptions, actions, perhaps identity.” Saskia Hendriks, a bioethicist at the U.S. National Institutes of Health, recently co-authored an essay on the emerging ethical questions in highly innovative brain research. In a June essay in The New England Journal of Medicine, Hendriks and a co-author, Christine Grady, outlined some of the thorny ethical questions related to brain research: What is the best way to protect the long-term interests of people who receive brain implants as part of a clinical trial? As technology gets better at decoding thoughts, how can researchers guard against violations of mental privacy? And what best way to prepare for the far-off possibility that consciousness may one day arise from work derived from human stem cells? Hendriks spoke about the essay in a Zoom interview. Our conversation has been edited for length and clarity.

Keyword: Robotics
Link ID: 29441 - Posted: 08.19.2024

By Paula Span Mary Peart, 67, a retired nurse in Manchester-by-the-Sea, Mass., began taking gabapentin a year and a half ago to reduce the pain and fatigue of fibromyalgia. The drug helps her climb stairs, walk her dog and take art lessons, she said. With it, “I have a life,” she said. “If I forget to take a dose, my pain comes right back.” Jane Dausch has a neurological condition called transverse myelitis and uses gabapentin as needed when her legs and feet ache. “It seems to be effective at calming down nerve pain,” said Ms. Dausch, 67, a retired physical therapist in North Kingstown, R.I. Amy Thomas, who owns three bookstores in the San Francisco Bay Area, takes gabapentin for rheumatoid arthritis. Along with yoga and physical therapy, “it’s probably contributing to it being easier for me to move around,” Ms. Thomas, 67, said. All three are taking the non-opioid pain drug for off-label uses. The only conditions for which gabapentin has been approved for adult use by the Food and Drug Administration are epileptic seizures, in 1993, and postherpetic neuralgia, the nerve pain that can linger after a bout of shingles, in 2002. But that has not stopped patients and health care providers from turning to gabapentin (whose brand names include Neurontin) for a startling array of other conditions, including sciatica, neuropathy from diabetes, lower back pain and post-surgery pain. Also: Agitation from dementia. Insomnia. Migraines. Itching. Bipolar disorder. Alcohol dependence. Evidence of effectiveness for these conditions is all over the map. The drug appears to provide relief for some patients with diabetic neuropathy but not with some other kinds of neuropathic pain. Several small studies indicate that gabapentin can reduce the itching associated with kidney failure. But the data for its effectiveness against low back pain or a number of psychiatric disorders are limited and show no meaningful impact. “It’s crazy how many indications it’s used for,” said Dr. Michael Steinman, a geriatrician at the University of California, San Francisco, and a co-director of the U.S. Deprescribing Research Network. “It’s become a we-don’t-know-what-else-to-do drug.” © 2024 The New York Times Company

Keyword: Pain & Touch; Drug Abuse
Link ID: 29438 - Posted: 08.19.2024

By Elena Kazamia It was a profound moment of connection. Carlos Casas could feel the elephant probing him, touching him with sound. The grunts emanating from the large male were of a frequency too low to hear, but Casas felt an agitation on his skin and deep inside his chest. “I was being scanned,” he says. At the time of the encounter, Casas was filming a project in Sri Lanka, and was holding a camera. But his interactions with the elephant gave the Catalonian filmmaker and installation artist an idea: What if instead of relying on images alone, he could use sound to create a physical connection between an audience of people and the subjects that fascinate him most, the animals with which we share life on this planet? Bestiari, his audio-visual project, now on display inside a former shipping warehouse at the Venice Biennale, weaves an immersive landscape for visitors. (You can explore some of the project, which was curated by Filipa Ramos, at the Instagram page for the installation.) Audio of the sounds the animals make is accompanied by video collected from remote camera traps set across national parks of Catalonia and Kenya, together with abstract film meant to capture the world as the animals see it, based on a combination of scientific research and artistic license. A series of texts serve as field guides to each animal featured in the installation. Entering the dark warehouse where Bestiari is housed, you are invited to lie on the floor, as if to fall asleep, before communing with seven different species: bees, donkeys, parakeets, snakes, bats, dolphins, and elephants. Each of the chosen species is represented by a speaker, customized to deliver the desired acoustics. Casas calls the speakers, “Trojan horses of meaning and communication.” The pitches and volumes were curated to be authentic to the original animal but perceptible by humans. For example, the echolocation chirps of bats have been slowed down to showcase the tonal progression of the sound. © 2024 NautilusNext Inc.,

Keyword: Hearing; Evolution
Link ID: 29421 - Posted: 08.03.2024

By Hannah Richter Humans aren’t the only animals that lose hearing as they grow older. Almost every mammal studied struggles to pick up some sounds as they age. Some veterinarians even fit dogs for tiny hearing aids. But at least one species of bat appears to be an exception. Reporting this month on the preprint server bioRxiv, scientists have discovered that big brown bats (Eptesicus fuscus) don’t hear any worse as they grow older, possibly because their ability to echolocate is so critical to their survival. “Hearing is kind of their superpower,” says Mirjam Knörnschild, a behavioral ecologist at the Museum of Natural History Berlin who was not involved with the work. The research, she and others say, could lead to new ways to understand—and possibly treat—hearing loss in humans. Bats actually have two superpowers. Not only can most of them echolocate—bouncing sound off objects to hunt and navigate—they also tend to be remarkably long-lived for their size. Most small mammals are short-lived, but compared with mice of similar stature, the big brown bat lives up to five times as long, sometimes topping out at 19 years old. That makes the species a fascinating target for studies of aging, says Grace Capshaw, a postdoctoral researcher at Johns Hopkins University. The bat auditory system is fundamentally the same as that of every other mammal, she says, so “bats can be a really powerful model for comparing how hearing works.” To test whether big brown bats lose their hearing over time, Capshaw and colleagues divided 23 wild-caught bats into groups of young and old, making 6 years—the mean age of the species—the dividing line. The researchers determined the bats’ ages using a precise genetic method that involves comparing each animal’s DNA with the DNA of bats with known ages. They then sedated the animals to conduct a hearing examination similar to those done on human infants.

Keyword: Hearing
Link ID: 29411 - Posted: 07.31.2024

By Miryam Naddaf About one-third of people who suffer from migraines experience a phenomenon known as aura before the headache.Credit: Tunatura/Getty For one billion people worldwide, the symptoms can be debilitating: throbbing head pain, nausea, blurred vision and fatigue that can last for days. But how brain activity triggers these severest of headaches — migraines — has long puzzled scientists. A study1 in mice, published in Science on 4 July, now offers clues about the neurological events that spark migraines. It suggests that a brief brain ‘blackout’ — when neuronal activity shuts down — temporarily changes the content of the cerebrospinal fluid, the clear liquid that surrounds the brain and spinal cord. This altered fluid, researchers suggest, travels through a previously unknown gap in anatomy to nerves in the skull where it activates pain and inflammatory receptors, causing headaches. “This work is a shift in how we think the headaches originate,” says Gregory Dussor, a neuroscientist at the University of Texas at Dallas in Richardson. “A headache might just be a general warning sign for lots of things happening inside the brain that aren’t normal.” “Migraine is actually protective in that way. The pain is protective because it’s telling the person to rest and recover and sleep,” says study co-author Maiken Nedergaard, a neuroscientist at the University of Copenhagen. The brain itself has no pain receptors; the sensation of headaches comes from areas outside the brain that are in the peripheral nervous system. But how the brain, which is not directly linked to the peripheral nervous system, triggers nerves to cause headaches is poorly understood, making them difficult to treat. © 2024 Springer Nature Limited

Keyword: Pain & Touch
Link ID: 29388 - Posted: 07.11.2024

Tijl Grootswagers Genevieve L Quek Manuel Varlet You are standing in the cereal aisle, weighing up whether to buy a healthy bran or a sugary chocolate-flavoured alternative. Your hand hovers momentarily before you make the final grab. But did you know that during those last few seconds, while you’re reaching out, your brain is still evaluating the pros and cons – influenced by everything from your last meal, the health star rating, the catchy jingle in the ad, and the colours of the letters on the box? Our recently published research shows our brains do not just think first and then act. Even while you are reaching for a product on a supermarket shelf, your brain is still evaluating whether you are making the right choice. Read news coverage based on evidence, not tweets Further, we found measuring hand movements offers an accurate window into the brain’s ongoing evaluation of the decision – you don’t have to hook people up to expensive brain scanners. What does this say about our decision-making? And what does it mean for consumers and the people marketing to them? There has been debate within neuroscience on whether a person’s movements to enact a decision can be modified once the brain’s “motor plan” has been made. Our research revealed not only that movements can be changed after a decision – “in flight” – but also the changes matched incoming information from a person’s senses. To study how our decisions unfold over time, we tracked people’s hand movements as they reached for different options shown in pictures – for example, in response to the question “is this picture a face or an object?” Put simply, reaching movements are shaped by ongoing thinking and decision-making. © 2010–2024, The Conversation US, Inc.

Keyword: Consciousness
Link ID: 29387 - Posted: 07.11.2024

By Rodrigo Pérez Ortega It starts with blind spots, flashing lights, and blurry vision—a warning of what’s to come. About an hour later, the dreadful headache kicks in. This pairing, a shining visual experience called an aura and then a headache, happens in about one-third of people who live with migraine. But researchers haven’t been able to figure out exactly how the two are linked at the molecular level. Now, a new study in mice, published today in Science, establishes a direct mechanism: molecules traveling in the fluid that bathes the brain. The finding could lead to new targets for much-needed migraine treatments. “It’s exciting,” says Rami Burstein, a translational neuroscientist at Harvard Medical School who was not involved in the new study. “It takes a very large step into understanding how something that happened in the brain can alter sensation or perception,” he says. It may also explain why the pain of migraine is experienced only in the head, he adds. Migraine, a debilitating neurological disorder, affects about 148 million people worldwide. Recently developed medications can help reduce headaches but are not effective for everyone. Although exact causes remain elusive, research has shown migraines most likely start with a pathological burst of neural activity. During an aura before a migraine, researchers have observed a seizurelike phenomenon called cortical spreading depression (CSD), in which a wave of abnormal neural firing slowly travels throughout the brain’s outer layer, or cortex. But because the brain itself contains no pain-sensing neurons, signals from the brain would have to somehow reach the peripheral nervous system—the nerves that communicate between the body parts and the brain—to cause a headache. In particular, they’d have to get to the two lumps of neurons below the brain called the trigeminal ganglia, which innervate the two sides of our face and head. Scientists knew that pain fibers from the trigeminal ganglion were nested in the meninges—the thin, delicate membranes that envelop and protect the brain.

Keyword: Pain & Touch
Link ID: 29380 - Posted: 07.06.2024