Regina G. Barber Ever had an itch you can't scratch? Maybe it's out of reach, or your hands are full, or you don't want to damage your skin. It can be deeply frustrating. And even though the itch response, or what scientists refer to simply as "itch," has a purpose — it's one of our bodies' alert systems — it can also go very wrong. The importance of a regular itch Itch is evolution's way of drawing our attention to something on our skin that needs removing. This could be a stinging bug, a nesting parasite or an irritating plant (poison ivy, anyone?!). All these things urge us to scratch, which generally removes the threat and soothes the itch. "We know that itch can activate sensory neurons and the signal will be transmitted to the brain. When we scratch the skin, somehow other neural circuits will be activated. And these neural circuits will suppress the itch circuits and alleviate the itch sensation," says Qin Liu, a neuroscientist at the Washington University School of Medicine in St. Louis. Because the itch sensation has separate neural circuitry from temperature, pressure and pain, applying pressure or ice or scratching can relieve an itch. They're effective neural distractions. Oftentimes, when someone experiences hives or an insect bite, histamine is involved, a chemical released by our immune system that can contribute to itchiness. So relieving that itch only requires antihistamine medication. "But most other forms of itch, like atopic dermatitis, eczema, other conditions, they don't actually have a pathway for histamine as the itch mediator," says Kwatra. © 2023 npr

Keyword: Pain & Touch
Link ID: 28929 - Posted: 09.27.2023

By Claudia López Lloreda When someone loses a hand or leg, they don’t just lose the ability to grab objects or walk—they lose the ability to touch and sense their surroundings. Prosthetics can restore some motor control, but they typically can’t restore sensation. Now, a preliminary studyposted to the preprint server bioRxiv this month—shows that by mimicking the activity of nerves, a device implanted in the remaining part of the leg helps amputees “feel” as they walk, allowing them to move faster and with greater confidence. “It's a really elegant study,” says Jacob George, neuroengineer at the University of Utah who was not involved with the research. Because the experiments go from a computational model to an animal model and then, finally humans, he says, “This work is really impactful, because it's one of the first studies that's done in a holistic way.” Patients with prosthetics often have a hard time adapting. One big issue is that they can’t accurately control the device because they can’t feel the pressure that they’re exerting on an object. Hand and arm amputees, for example, are more prone to drop or break things. As a result, some amputees refuse to use such prosthetics. In the past few years, researchers have been working on prosthetic limbs that provide more natural sensory feedback both to help control the device better and give them back a sense of agency over their robotic limb. In a critical study in 2019, George and his team showed that so-called biomimetic feedback, sensory information that aims to resemble the natural signals that occur with touch, allowed a patient who’d lost his hand to more precisely grip fragile objects such as eggs and grapes. But such studies have been limited to single patients. They’ve also left many questions unanswered about how exactly this feedback helps with motor control and improves the use of the prosthetic. So in the new work, researchers used a computer model that re-creates how nerves in the foot respond to different inputs, such as feeling pressure. The goal was to create natural patterns of neural activity that might occur when sensing something with the foot or walking. © 2023 American Association for the Advancement of Science.

Keyword: Pain & Touch; Robotics
Link ID: 28863 - Posted: 08.02.2023

By Charlotte Stoddart Charlotte Stoddart: Can a sugar pill make you feel better? What about the rituals surrounding a visit to the doctor? Can the care of a doctor or your trust in them reduce the amount of pain you feel? I’m Charlotte Stoddart and this is Knowable. This episode is all about the placebo effect. We’re going to look in detail at one key paper to learn how the placebo effect has been used in medicine and how it’s been understood and misunderstood. The paper is called “The Powerful Placebo.” It was written by Henry Beecher and published in JAMA, the Journal of the American Medical Association, in 1955. I chose this paper because it’s often referred to as a classic, and it’s still one of the most frequently cited papers on the placebo effect. I’ve enlisted the help of Ted Kaptchuk, who knows the paper well. Ted Kaptchuk: I enjoyed rereading it, actually. It’s a remarkable paper. I’ve read it probably 15 times in my life. Charlotte Stoddart: Ted is director of the Program in Placebo Studies at the Beth Israel Deaconess Medical Center in Boston and a professor of medicine at Harvard Medical School, where Henry Beecher also held a professorship. Beecher also worked at Massachusetts General Hospital. Charlotte Stoddart: During the Second World War, Beecher served in the US Army, and there’s a story about how that experience got him interested in the placebo effect. It goes like this: Beecher was working at a military hospital. One day, a badly injured soldier needed surgery, but the hospital had run out of morphine. So Beecher injected the soldier with saline solution instead. The soldier relaxed and Beecher carried out the operation without any real anesthetic. This, so the story goes, is when Beecher realized the power of the mind over the body. There are several different versions of this story, but Ted says it’s likely some version of it is true. © 2023 Annual Reviews

Keyword: Pain & Touch; Attention
Link ID: 28832 - Posted: 06.28.2023

John Michael Streicher Opioid drugs such as morphine and fentanyl are like the two-faced Roman god Janus: The kindly face delivers pain relief to millions of sufferers, while the grim face drives an opioid abuse and overdose crisis that claimed nearly 70,000 lives in the U.S. in 2020 alone. Scientists like me who study pain and opioids have been seeking a way to separate these two seemingly inseparable faces of opioids. Researchers are trying to design drugs that deliver effective pain relief without the risk of side effects, including addiction and overdose. One possible path to achieving that goal lies in understanding the molecular pathways opioids use to carry out their effects in your body. How do opioids work? The opioid system in your body is a set of neurotransmitters your brain naturally produces that enable communication between neurons and activate protein receptors. These neurotransmitters include small proteinlike molecules like enkephalins and endorphins. These molecules regulate a tremendous number of functions in your body, including pain, pleasure, memory, the movements of your digestive system and more. Analysis of the world, from experts Opioid neurotransmitters activate receptors that are located in a lot of places in your body, including pain centers in your spinal cord and brain, reward and pleasure centers in your brain, and throughout the neurons in your gut. Normally, opioid neurotransmitters are released in only small quantities in these exact locations, so your body can use this system in a balanced way to regulate itself. The opioids your body produces and opioid drugs bind to the same receptors. The problem comes when you take an opioid drug like morphine or fentanyl, especially at high doses for a long time. These drugs travel through the bloodstream and can activate every opioid receptor in your body. You’ll get pain relief through the pain centers in your spinal cord and brain. But you’ll also get a euphoric high when those drugs hit your brain’s reward and pleasure centers, and that could lead to addiction with repeated use. When the drug hits your gut, you may develop constipation, along with other common opioid side effects. Targeting opioid signal transduction How can scientists design opioid drugs that won’t cause side effects? One approach my research team and I take is to understand how cells respond when they receive the message from an opioid neurotransmitter. Neuroscientists call this process opioid receptor signal transduction. Just as neurotransmitters are a communication network within your brain, each neuron also has a communication network that connects receptors to proteins within the neuron. When these connections are made, they trigger specific effects like pain relief. So, after a natural opioid neurotransmitter or a synthetic opioid drug activates an opioid receptor, it activates proteins within the cell that carry out the effects of the neurotransmitter or the drug. © 2010–2023, The Conversation US, Inc.

Keyword: Drug Abuse; Pain & Touch
Link ID: 28809 - Posted: 06.03.2023

By Laura Sanders Scientists can see chronic pain in the brain with new clarity. Over months, electrodes implanted in the brains of four people picked up specific signs of their persistent pain. This detailed view of chronic pain, described May 22 in Nature Neuroscience, suggests new ways to curtail the devastating condition. The approach “provides a way into the brain to track pain,” says Katherine Martucci, a neuroscientist who studies chronic pain at Duke University School of Medicine. Chronic pain is incredibly common. In the United States from 2019 to 2020, more adults were diagnosed with chronic pain than with diabetes, depression or high blood pressure, researchers reported May 16 in JAMA Network Open. Chronic pain is also incredibly complex, an amalgam influenced by the body, brain, context, emotions and expectations, Martucci says. That complexity makes chronic pain seemingly invisible to an outsider, and very difficult to treat. One treatment approach is to stimulate the brain with electricity. As part of a clinical trial, researchers at the University of California, San Francisco implanted four electrode wires into the brains of four volunteers with chronic pain. These electrodes can both monitor and stimulate nerve cells in two brain areas: the orbitofrontal cortex, or OFC, and the anterior cingulate cortex, or ACC. The OFC isn’t known to be a key pain influencer in the brain, but this region has lots of neural connections to pain-related areas, including the ACC, which is thought to be involved in how people experience pain. But before researchers stimulated the brain, they needed to know how chronic pain was affecting it. For about 3 to 6 months, the implanted electrodes monitored brain signals of these people as they went about their lives. During that time, the participants rated their pain on standard scales two to eight times a day. © Society for Science & the Public 2000–2023.

Keyword: Pain & Touch; Brain imaging
Link ID: 28795 - Posted: 05.23.2023

By Priyanka Runwal Researchers have for the first time recorded the brain’s firing patterns while a person is feeling chronic pain, paving the way for implanted devices to one day predict pain signals or even short-circuit them. Using a pacemaker-like device surgically placed inside the brain, scientists recorded from four patients who had felt unremitting nerve pain for more than a year. The devices recorded several times a day for up to six months, offering clues for where chronic pain resides in the brain. The study, published on Monday in the journal Nature Neuroscience, reported that the pain was associated with electrical fluctuations in the orbitofrontal cortex, an area involved in emotion regulation, self-evaluation and decision making. The research suggests that such patterns of brain activity could serve as biomarkers to guide diagnosis and treatment for millions of people with shooting or burning chronic pain linked to a damaged nervous system. “The study really advances a whole generation of research that has shown that the functioning of the brain is really important to processing and perceiving pain,” said Dr. Ajay Wasan, a pain medicine specialist at the University of Pittsburgh School of Medicine, who wasn’t involved in the study. About one in five American adults experience chronic pain, which is persistent or recurrent pain that lasts longer than three months. To measure pain, doctors typically rely on patients to rate their pain, using either a numerical scale or a visual one based on emojis. But self-reported pain measures are subjective and can vary throughout the day. And some patients, like children or people with disabilities, may struggle to accurately communicate or score their pain. “There’s a big movement in the pain field to develop more objective markers of pain that can be used alongside self-reports,” said Kenneth Weber, a neuroscientist at Stanford University, who was not involved in the study. In addition to advancing our understanding of what neural mechanisms underlie the pain, Dr. Weber added, such markers can help validate the pain experienced by some patients that is not fully appreciated — or is even outright ignored — by their doctors. © 2023 The New York Times Company

Keyword: Pain & Touch; Brain imaging
Link ID: 28794 - Posted: 05.23.2023

Katharine Sanderson Researchers have developed an electronic skin that can mimic the same process that causes a finger, toe or limb to move when poked or scalded. The technology could lead to the development of a covering for prosthetic limbs that would give their wearers a sense of touch, or help to restore sensation in people whose skin has been damaged. The ‘e-skin’ was developed in the laboratory of chemical engineer Zhenan Bao at Stanford University in California. Her team has long been trying to make a prosthetic skin that is soft and flexible, but that can also transmit electrical signals to the brain to allow the wearer to ‘feel’ pressure, strain or changes in temperature. The latest work, published on 18 May in Science1, describes a thin, flexible sensor that can transmit a signal to part of the motor cortex in a rat’s brain that causes the animal’s leg to twitch when the e-skin is pressed or squeezed. “This current e-skin really has all the attributes that we have been dreaming about,” says Bao. “We have been talking about it for a long time.” In healthy living skin, mechanical receptors sense information and convert it into electrical pulses that are transmitted through the nervous system to the brain. To replicate this, an electronic skin needs sensors and integrated circuits, which are usually made from rigid semiconductors. Flexible electronic systems are already available, but they typically work only at high voltages that would be unsafe for wearable devices. To make a fully soft e-skin, Bao’s team developed a flexible polymer for use as a dielectric — a thin layer in a semiconductor device that determines the strength of the signal and the voltage needed to run the device. The researchers then used the dielectric to make stretchy, flexible arrays of transistors, combined into a sensor that was thin and soft like skin. © 2023 Springer Nature Limited

Keyword: Pain & Touch; Robotics
Link ID: 28790 - Posted: 05.21.2023

By Lucy Odling-Smee Philip Kass spends 90% of his day lying on a twin bed in a sparsely decorated room that used to belong to his niece. He takes most meals with a plate balanced on his chest, and he usually watches television because reading is too stressful. “I’m barely living,” he told me on a warm night in June last year. Ever since a back injury 23 years ago, pain has been eating away at Kass’s life. It has cost him his career, his relationships, his mobility and his independence. Now 55, Kass lives with his sister and her family in San Francisco, California. He occasionally joins them for dinner, which means he’ll eat while standing. And once a day he tries to walk four or five blocks around the neighbourhood. But he worries that any activity, walking too briskly or sitting upright for more than a few minutes, will trigger a fresh round of torment that can take days or weeks to subside. Philip Kass has dealt with pain for more than two decades. Some of what Kass describes is familiar. I have been pinned to the floor by spinal pain several times in my life. In my twenties, I was immobilized for three months. In my thirties and forties, each episode of severe pain lasted more than a year. I spent at least another half decade standing or pacing through meetings, meals and movies — for fear that even a few minutes spent sitting would result in weeks of disabling pain. For years, I read anything I could find to better understand why my pain persisted.

Keyword: Pain & Touch
Link ID: 28723 - Posted: 03.29.2023

Miryam Naddaf It is thanks to proteins in the nose called odour receptors that we find the smell of roses pleasant and that of rotting food foul. But little is known about how these receptors detect molecules and translate them into scents. Now, for the first time, researchers have mapped the precise 3D structure of a human odour receptor, taking a step forwards in understanding the most enigmatic of our senses. The study, published in Nature on 15 March1, describes an olfactory receptor called OR51E2 and shows how it ‘recognizes’ the smell of cheese through specific molecular interactions that switch the receptor on. “It’s basically our first picture of any odour molecule interacting with one of our odour receptors,” says study co-author Aashish Manglik, a pharmaceutical chemist at the University of California, San Francisco. Smell mystery The human genome contains genes encoding 400 olfactory receptors that can detect many odours. Mammalian odour-receptor genes were first discovered in rats by molecular biologist Richard Axel and biologist Linda Buck in 19912. Researchers in the 1920s estimated that the human nose could discern around 10,000 smells3, but a 2014 study suggests that we can distinguish more than one trillion scents4. Each olfactory receptor can interact with only a subset of smelly molecules called odorants — and a single odorant can activate multiple receptors. It is “like hitting a chord on a piano”, says Manglik. “Instead of hitting a single note, it’s a combination of keys that are hit that gives rise to the perception of a distinct odour.” Beyond this, little is known about exactly how olfactory receptors recognize specific odorants and encode different smells in the brain. Technical challenges in producing mammalian olfactory-receptor proteins using standard laboratory methods have made it difficult to study how these receptors bind to odorants. © 2023 Springer Nature Limited

Keyword: Chemical Senses (Smell & Taste)
Link ID: 28710 - Posted: 03.18.2023

ByClaudia Lopez Lloreda Peanuts have a dark side. In some people, they can cause a dangerous and sometimes deadly allergic reaction marked by a sharp drop in body temperature and blood pressure, as well as difficulty breathing. This anaphylactic shock has typically been blamed on the immune system going into overdrive. But a new study in mice pegs an additional culprit: the nervous system. The findings, reported today in Science Immunology, “are line with what people thought but no one was actually able to demonstrate,” says Sebastien Talbot, a neuroimmunologist at Queen’s University who was not involved in the study. The work, he says, could open up new targets to treat severe allergic reactions in people. Anaphylaxis strikes about one in 50 individuals in the United States every year. Besides peanuts, bee stings and some medicines are common triggers. These allergens cause the immune system’s mast cells to release a barrage of histamine and other molecules that spread throughout the body, dilating blood vessels and narrowing airways. Body temperature can also drop, making people feel cold and clammy, though why this happens has been less clear. Mice experience anaphylaxis, too. When exposed to an allergen, they lie on their bellies and stretch out. Such behaviors are controlled by the central nervous system, which made Soman Abraham, an immunologist at Duke University, suspect nerves may also play a role in severe allergic reactions. To find out, he and colleagues gave the mice ovalbumin—the main protein found in egg whites and a known trigger of anaphylaxis—and used electrodes and microscopy to record and measure neuron activity. As in humans, the rodents’ body temperature dropped—about 10°C. But the mice’s brains didn’t register this as a sudden freeze; instead, brain areas that typically respond to heat had higher levels of activity. This false feeling of warmth explains why the animals stretch out as if they’re overheating even as their body temperature drops.

Keyword: Neuroimmunology
Link ID: 28706 - Posted: 03.18.2023

By Christina Jewett The Food and Drug Administration has approved a Pfizer nasal spray for treatment of migraines that uses a different therapy from other nasal products on the market for severe headache pain, the company said on Friday. The fast-acting treatment, which is called zavegepant and will be sold as Zavzpret, performed better than a placebo in relieving pain and patients’ most bothersome symptoms, according to clinical trial results published in the journal Lancet Neurology. Participants in the trial who took the medication were more likely to report returning to normal function 30 minutes to two hours after taking it. The gains, though, were not significant for every patient. A study tracked the experience of 1,269 patients — half on the drug and half on a placebo — focusing on how they reported feeling two hours after using either substance. About 24 percent on the medication reported freedom from pain, compared to about 15 percent who took a placebo, according to the study. Dr. Timothy A. Collins, chief of the headache division at Duke University Medical Center’s neurology department, said the product gave doctors a new option in a nasal spray format that patients with migraines tended to appreciate. He said the condition often comes with nausea, so swallowing a pill can be unpleasant. He also said the drug presented few side effects, like drowsiness, that had been reported with other products. “We’ve been waiting for this medication to come out,” Dr. Collins said. “It’s a really helpful addition to migraine management.” One additional upside of the medication is that it’s safe for patients who have had a heart attack or a stroke, he added. Pfizer said the medication would be available in pharmacies in July, but did not disclose the estimated price of the new spray. The company estimated that nearly 40 million people in the United States suffered from migraines each year. © 2023 The New York Times Company

Keyword: Pain & Touch
Link ID: 28701 - Posted: 03.15.2023

By Jack Tamisiea An elephant’s trunk has 40,000 muscles and weighs more than a Burmese python. The appendage is strong enough to uproot a tree, yet sensitive enough to suction up fragile tortilla chips. But how does an elephant’s brain help accomplish these feats of dexterity? That has been difficult to study, according to Michael Brecht, a neuroscientist at the Humboldt University of Berlin. Weighing in excess of 10 pounds, the elephant’s brain degrades quickly after death and is a hassle to store. “I tend to think that the big animals are a bit neglected because we don’t do enough work on big brains,” Dr. Brecht said. Dr. Brecht and his colleagues were fortunate enough to gain access to a trove of elephant brains from animals that had died of natural causes or were euthanized for health reasons and ended up either frozen or in a fixative substance at the Leibniz Institute for Zoo and Wildlife Research in Berlin. In a study published Wednesday in the journal Science Advances, Dr. Brecht and his colleagues reported that elephants had more facial neurons than any other land mammal, which might contribute to trunk dexterity and other anatomical abilities. The study also helped to pinpoint major differences between the neural wirings of African savanna elephants and Asian elephants. Using the brains of four Asian elephants and four African savanna elephants, the researchers homed in on the facial nucleus, a bundle of neurons concentrated in the brainstem and hooked up to facial nerves. In mammals, these neurons serve as the control center for facial muscles. They’re in command whenever you wrinkle your nose, purse your lips or raise your eyebrows. They also help elephants employ their trunks. The researchers divided the facial nucleus into regions of neurons that controlled the elephant’s ears, lips and trunk. African elephants sported 63,000 facial neurons, while their Asian cousins had 54,000. The only mammals with more are dolphins, which pack nearly 90,000 facial neurons into their sensitive snouts. While his team expected both African savanna and Asian elephants to possess massive stores of facial neurons, Dr. Brecht said the discrepancy between the two species was noteworthy. © 2022 The New York Times Company

Keyword: Evolution; Pain & Touch
Link ID: 28533 - Posted: 10.28.2022

By Jim Robbins Tens of thousands of bar-tailed godwits are taking advantage of favorable winds this month and next for their annual migration from the mud flats and muskeg of southern Alaska, south across the vast expanse of the Pacific Ocean, to the beaches of New Zealand and eastern Australia. They are making their journey of more than 7,000 miles by flapping night and day, without stopping to eat, drink or rest. “The more I learn, the more amazing I find them,” said Theunis Piersma, a professor of global flyway ecology at the University of Groningen in the Netherlands and an expert in the endurance physiology of migratory birds. “They are a total evolutionary success.” The godwit’s epic flight — the longest nonstop migration of a land bird in the world — lasts from eight to 10 days and nights through pounding rain, high winds and other perils. It is so extreme, and so far beyond what researchers knew about long-distance bird migration, that it has required new investigations. In a recent paper, a group of researchers said the arduous journeys challenge “underlying assumptions of bird physiology, orientation, and behavior,” and listed 11 questions posed by such migrations. Dr. Piersma called the pursuit of answers to these questions “the new ornithology.” The extraordinary nature of what bar-tailed and other migrating birds accomplish has been revealed in the last 15 years or so with improvements to tracking technology, which has given researchers the ability to follow individual birds in real time and in a detailed way along the full length of their journey. “You know where a bird is almost to the meter, you know how high it is, you know what it’s doing, you know its wing-beat frequency,” Dr. Piersma said. “It’s opened a whole new world.” The known distance record for a godwit migration is 13,000 kilometers, or nearly 8,080 miles. © 2022 The New York Times Company

Keyword: Animal Migration; Sleep
Link ID: 28484 - Posted: 09.21.2022

By Anil Oza Sitting alone in the cockpit of a small biplane, Martin Wikelski listens for the pings of a machine by his side. The sonic beacons help the ecologist stalk death’s-head hawkmoths (Acherontia atropos) fluttering across the dark skies above Konstanz, Germany — about 80 kilometers north of the Swiss Alps. The moths, nicknamed for the skull-and-crossbones pattern on their backs, migrate thousands of kilometers between northern Africa and the Alps during the spring and fall. Many migratory insects go where the wind takes them, says Ring Carde, an entomologist at the University of California, Riverside who is not a member of Wikelski’s team. Death’s-head hawkmoths appear to be anything but typical. “When I follow them with a plane, I use very little gas,” says Wikelski, of the Max Planck Institute of Animal Behavior in Munich. “That shows me that they are supposedly choosing directions or areas that are probably supported by a little bit of updraft.” A new analysis of data collected from 14 death’s-head hawkmoths suggest that these insects indeed pilot themselves, possibly relying in part on an internal compass attuned to Earth’s magnetic field. The moths not only fly along a straight path, they also stay the course even when winds change, Wikelski and colleagues report August 11 in Science. The findings could help predict how the moths’ flight paths might shift as the globe continues warming, Wikelski says. Like many animals, death’s-head hawkmoths will probably move north in search of cooler temperatures, he suspects. To keep tabs on the moths, Wikelski’s team glued radio transmitters to their backs, which is easier to do than one might expect. “Death’s-head hawkmoths are totally cool,” Wikelski says. They’re also huge. Weighing as much as three jellybeans, the moths are the largest in Europe. That makes attaching the tiny tags a cinch, though the moths don’t like it very much. “They talk to you, they shout at you a little bit,” he says. © Society for Science & the Public 2000–2022.

Keyword: Animal Migration
Link ID: 28451 - Posted: 08.27.2022

By Betsy Mason 08.05.2022 What is special about humans that sets us apart from other animals? Less than some of us would like to believe. As scientists peer more deeply into the lives of other animals, they’re finding that our fellow creatures are far more emotionally, socially, and cognitively complex than we typically give them credit for. A deluge of innovative research is revealing that behavior we would call intelligent if humans did it can be found in virtually every corner of the animal kingdom. Already this year scientists have shown that Goffin’s cockatoos can use multiple tools at once to solve a problem, Australian Magpies will cooperate to remove tracking devices harnessed to them by scientists, and a small brown songbird can sometimes keep time better than the average professional musician — and that’s just among birds. This pileup of fascinating findings may be at least partly responsible for an increase in people’s interest in the lives of other animals — a trend that’s reflected in an apparent uptick in books and television shows on the topic, as well as in legislation concerning other species. Public sentiment in part pushed the National Institutes of Health to stop supporting biomedical research on chimpanzees in 2015. In Canada, an outcry led to a ban in 2019 on keeping cetaceans like dolphins and orcas in captivity. And earlier this year, the United Kingdom passed an animal welfare bill that officially recognizes that many animals are sentient beings capable of suffering, including invertebrates like octopuses and lobsters. Many of these efforts are motivated by human empathy for animals we’ve come to see as intelligent, feeling beings like us, such as chimpanzees and dolphins. But how can we extend that concern to the millions of other species that share the planet with us?

Keyword: Vision; Hearing
Link ID: 28447 - Posted: 08.27.2022

By Chantel Prat I remember all too well that day early in the pandemic when we first received the “stay at home” order. My attitude quickly shifted from feeling like I got a “snow day” to feeling like a bird in a cage. Being a person who is both extraverted by nature and not one who enjoys being told what to do, the transition was pretty rough. But you know what? I got used to it. Though the pandemic undoubtedly affected some of your lives more than others, I know it touched every one of us in ways we will never forget. And now, after two years and counting, I am positive that every person reading this is fundamentally different from when the pandemic started. Because that’s how our brains work. They are molded by our experiences so that we can fit into all kinds of different situations—even the decidedly suboptimal ones. MOTHER TONGUE: Neuroscientist and psychologist Chantel Prat says the languages we speak play a huge role in shaping our minds and brains. Photo by Shaya Bendix Lyon. This is actually one of the most human things about all of our brains. In fact, according to some contemporary views of human evolution, our ancestors underwent a “cognitive revolution” precisely because they were forced to adapt. Based on evidence suggesting that the size of our ancestors’ brains increased following periods of extreme weather instability, one popular explanation for our remarkable flexibility is that the hominids who were not able to adapt to environmental changes didn’t survive. In other words, the brains of modern humans were selected for their ability to learn and adapt to changing environments. But one of the major costs of this remarkable flexibility is that humans are born without any significant preconceived notions about how things work. If you’ve ever had a conversation with someone about an event you both participated in that left you feeling like one of you was delusional because your stories were so different, you might have a hint about how much your experiences have shaped the way you understand the world around you. This can be insanely frustrating because—let’s face it—our own brains are really convincing when they construct our personal version of reality. Remember the Dress? Though it can feel like gaslighting when someone has a different reality from yours, it’s also entirely possible that you both were reporting your version of the truth. At the end of the day, the way people remember a story reflects differences in the way they experienced the original event. The scientific explanation for this boils down to differences in perspective. © 2022 NautilusThink Inc,

Keyword: Attention; Vision
Link ID: 28427 - Posted: 08.11.2022

By Betsy Mason What is special about humans that sets us apart from other animals? Less than some of us would like to believe. As scientists peer more deeply into the lives of other animals, they’re finding that our fellow creatures are far more emotionally, socially, and cognitively complex than we typically give them credit for. A deluge of innovative research is revealing that behavior we would call intelligent if humans did it can be found in virtually every corner of the animal kingdom. Already this year scientists have shown that Goffin’s cockatoos can use multiple tools at once to solve a problem, Australian Magpies will cooperate to remove tracking devices harnessed to them by scientists, and a small brown songbird can sometimes keep time better than the average professional musician — and that’s just among birds. This pileup of fascinating findings may be at least partly responsible for an increase in people’s interest in the lives of other animals — a trend that’s reflected in an apparent uptick in books and television shows on the topic, as well as in legislation concerning other species. Public sentiment in part pushed the National Institutes of Health to stop supporting biomedical research on chimpanzees in 2015. In Canada, an outcry led to a ban in 2019 on keeping cetaceans like dolphins and orcas in captivity. And earlier this year, the United Kingdom passed an animal welfare bill that officially recognizes that many animals are sentient beings capable of suffering, including invertebrates like octopuses and lobsters. Many of these efforts are motivated by human empathy for animals we’ve come to see as intelligent, feeling beings like us, such as chimpanzees and dolphins. But how can we extend that concern to the millions of other species that share the planet with us?

Keyword: Vision; Hearing
Link ID: 28420 - Posted: 08.06.2022

R. Douglas Fields Neuroscientists, being interested in how brains work, naturally focus on neurons, the cells that can convey elements of sense and thought to each other via electrical impulses. But equally worthy of study is a substance that’s between them — a viscous coating on the outside of these neurons. Roughly equivalent to the cartilage in our noses and joints, the stuff clings like a fishing net to some of our neurons, inspiring the name perineuronal nets (PNNs). They’re composed of long chains of sugar molecules attached to a protein scaffolding, and they hold neurons in place, preventing them from sprouting and making new connections. Given this ability, this little-known neural coating provides answers to some of the most puzzling questions about the brain: Why do young brains absorb new information so easily? Why are the fearful memories that accompany post-traumatic stress disorder (PTSD) so difficult to forget? Why is it so hard to stop drinking after becoming dependent on alcohol? And according to new research from the neuroscientist Arkady Khoutorsky and his colleagues at McGill University, we now know that PNNs also explain why pain can develop and persist so long after a nerve injury. Neural plasticity is the ability of neural networks to change in response to experiences in life or to repair themselves after brain injury. Such opportunities for effortless change are known as critical periods when they occur early in life. Consider how easily babies pick up language, but how difficult it is to learn a foreign language as an adult. In a way, this is what we’d want: After the intricate neural networks that allow us to understand our native language are formed, it’s important for them to be locked down, so the networks remain relatively undisturbed for the rest of our lives. All Rights Reserved © 2022

Keyword: Pain & Touch; Glia
Link ID: 28415 - Posted: 07.30.2022

ByVirginia Morell We swat bees to avoid painful stings, but do they feel the pain we inflict? A new study suggests they do, a possible clue that they and other insects have sentience—the ability to be aware of their feelings. “It’s an impressive piece of work” with important implications, says Jonathan Birch, a philosopher and expert on animal sentience at the London School of Economics who was not involved with the paper. If the study holds up, he says, “the world contains far more sentient beings than we ever realized.” Previous research has shown honey bees and bumble bees are intelligent, innovative, creatures. They understand the concept of zero, can do simple math, and distinguish among human faces (and probably bee faces, too). They’re usually optimistic when successfully foraging, but can become depressed if momentarily trapped by a predatory spider. Even when a bee escapes a spider, “her demeanor changes; for days after, she’s scared of every flower,” says Lars Chittka, a cognitive scientist at Queen Mary University of London whose lab carried out that study as well as the new research. “They were experiencing an emotional state.” To find out whether these emotions include pain, Chittka and colleagues looked at one of the criteria commonly used for defining pain in animals: “motivational trade-offs.” People will endure the pain of a dentist’s drill for the longer term benefits of healthy teeth, for example. Similarly, hermit crabs will leave preferred shells to escape an electric shock only when given a particularly high jolt—an experiment that demonstrated crabs can tell the difference between weak and strong painful stimuli, and decide how much pain is worth enduring. That suggests crabs do feel pain and don’t simply respond reflexively to an unpleasant stimulus. Partly as a result of that study, crabs (and other crustaceans, including lobsters and crayfish) are recognized as sentient under U.K. law. © 2022 American Association for the Advancement of Science

Keyword: Pain & Touch; Evolution
Link ID: 28410 - Posted: 07.30.2022

By Meghan Rosen A flexible electronic implant could one day make pain management a lot more chill. Created from materials that dissolve in the body, the device encircles nerves with an evaporative cooler. Implanted in rats, the cooler blocked pain signals from zipping up to the brain, bioengineer John Rogers and colleagues report in the July 1 Science. Though far from ready for human use, a future version could potentially let “patients dial up or down the pain relief they need at any given moment,” says Rogers, of Northwestern University in Evanston, Ill. Scientists already knew that low temperatures can numb nerves in the body. Think of frozen fingers in the winter, Rogers says. But mimicking this phenomenon with an electronic implant isn’t easy. Nerves are fragile, so scientists need something that gently hugs the tissues. And an ideal implant would be absorbed by the body, so doctors wouldn’t have to remove it. Made from water-soluble materials, the team’s device features a soft cuff that wraps around a nerve like toilet paper on a roll. Tiny channels snake down its rubbery length. When liquid coolant that’s pumped through the channels evaporates, the process draws heat from the underlying nerve. A temperature sensor helps scientists hit the sweet spot — cold enough to block pain but not too cold to damage the nerve. The researchers wrapped the implant around a nerve in rats and tested how they responded to having a paw poked. With the nerve cooler switched on, scientists could apply about seven times as much pressure as usual before the animals pulled their paws away. That’s a sign that the rats’ senses had grown sluggish, Rogers says. © Society for Science & the Public 2000–2022.

Keyword: Pain & Touch
Link ID: 28387 - Posted: 07.05.2022