Chapter 8. General Principles of Sensory Processing, Touch, and Pain

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By Carl Zimmer Last week, ladybugs briefly took over the news cycle. Meteorologists at the National Weather Service were looking over radar images in California on the night of June 4 when they spotted what looked like a wide swath of rain. But there were no clouds. The meteorologists contacted an amateur weather-spotter directly under the mysterious disturbance. He wasn’t getting soaked by rain. Instead, he saw ladybugs. Everywhere. Radar apparently had picked up a cloud of migrating ladybugs spread across 80 miles, with a dense core ten miles wide floating 5,000 feet to 9,000 feet in the air. As giant as the swarm was, the meteorologists lost track of it. The ladybugs disappeared into the night. Compared to other animal migrations, the migrations of insects are a scientific mystery. It’s easy to spot a herd of wildebeest making its way across the savanna. Insects, even in huge numbers, move from place to place without much notice. One day you look around, and ladybugs are everywhere. “The migrations themselves are totally invisible,” said Jason Chapman, an ecologist at the University of Exeter in Britain. Dr. Chapman and his colleagues are using radar to bring insect migrations to light. The scientists help run a unique network of small radar stations in southern England designed to scan the sky 24 hours a day, spotting insects flying overhead. “These radars are fantastic,” said Dr. Chapman. “We have a lot of information about every individual insect that flies over overhead, including a measure of the shape and a measure of their size.” © 2019 The New York Times Company

Keyword: Animal Migration
Link ID: 26329 - Posted: 06.14.2019

By Sarah Baird Few topics occupy pregnant women’s minds in the months leading up to birth more than devising a plan for pain management during labor. In the United States, the options during delivery have long been pretty limited. On one side of the dichotomy is a completely unmedicated childbirth, where visualization and breathing techniques offer a mind-over-matter approach to labor pain. On the other side, epidurals are the pain-eliminating gold standard — but can come with plenty of trade-offs. Across the world, though, nitrous oxide (yes, “laughing gas”) has long been standard — dating back to the turn-of-the-century — in delivery rooms, allowing women to help mitigate the pain of labor while remaining present and, perhaps best of all, maintaining their sense of control. Now, this low-stakes form of delivery room relief is finally taking hold in the United States as women seek out a wider range of options for their birthing experience. Nitrous oxide is a blend of 50 percent nitrous and 50 percent oxygen that women are able to self-administer during labor by holding a face mask over their nose and mouth and breathing deeply. (The 50/50 ratio is a set concentration and cannot be raised or lowered, unlike the dialed system in a dentist’s office which can be increased up to 70 percent nitrogen.) The option, unlike other types of pain relief, requires no I.V., does not limit mobility and will not slow contractions. The effects of nitrous kick in within 30 to 50 seconds of beginning inhalation, providing a very different form of pain management than other methods available. “It’s been described as a dissociative effect, so it reduces anxiety related to pain and kind of disassociates [women] from their pain,” said Kelly Curlee, R.N., director of inpatient nursing at Texas Health Cleburne in Cleburne, Tex. “Pain breeds fear, fear breeds pain. That’s kind of a cycle that nitrous helps break.” © 2019 The New York Times Company

Keyword: Pain & Touch
Link ID: 26319 - Posted: 06.10.2019

Patti Neighmond Jeannine, who is 37 and lives in Burbank, Calif., has endured widespread pain since she was 8. She has been examined by dozens of doctors, but none of their X-rays, MRIs or other tests have turned up any evidence of physical injury or damage. Over the years, desperate for relief, she tried changing her diet, wore belts to correct her posture and exercised to strengthen muscles. Taking lots of ibuprofen helped, she says, but doctors warned her that taking too much could cause gastric bleeding. Nothing else eased her discomfort. On a pain scale of 0 to 10, her pain ranged from "7 to 9, regularly," she says. Around 50 million Americans suffer from chronic pain. Most of us think of pain as something that arises after a physical injury, accident or damage from an illness or its treatment. But researchers are learning that, in some people, there can be another source of chronic pain. Repeated exposure to psychological trauma, or deep anxiety or depression — especially in childhood — can leave a physical imprint on the brain that can make some people, like Jeannine, more vulnerable to chronic pain, scientists say. (We are not using her last name for reasons of privacy.) Jeannine was eventually diagnosed with fibromyalgia — a condition characterized by widespread pain throughout the body, among other symptoms. The cause is unknown and likely varies from person to person. The pain Jeannine experienced was physical. She'd feel "lightning bolts, kind of going up through my shoulders to my neck to my head," she says. Other times, she'd suddenly experience the shooting pain of sciatica in her legs, and she often suffered from a "grinding pain" in her hips. "I would feel like I can't walk anymore — it was just so very painful to walk." © 2019 npr

Keyword: Pain & Touch
Link ID: 26316 - Posted: 06.10.2019

By Frances Cronin Health reporter Alison Cameron, from Dorset, was 17 when she had appendicitis and went into hospital. "I had my appendix out and I remember I came round out of the anaesthetic screaming, the pain was something else." It was the start of a "horrendous" three years of investigation before "they came to the conclusion through a process of elimination, it was nerve damage". Over the next 30 years, Alison had more than 50 injections, known as cryoblocks, to freeze the site of her abdominal pain, but none of them stopped the pain for more than six months. This left her needing high doses of painkillers which left her unable to eat or drink - and she ended up on a feeding tube which led to her losing weight, and her health deteriorating. But she says she always tried to stay positive, which was instilled in her by her mum. "No matter how bad things have been, I've always been able to find a positive at the end of the day. That isn't saying that I didn't have some very, very low moments. "I miscarried seven times - six of which were definitely down to the pain. So not only have I paid the price - but also those potential lives." She managed to have two children in the gaps between treatment, and now has three grandchildren. The eldest burst into tears the first time she saw Alison without an eating tube, "as that, for her, wasn't normal granny". Five years ago, a cryoblock caused a collapsed lung, and Alison was referred to consultant neurosurgeon Girish Vajramani at the University Hospital Southampton. "Alison is one of the most challenging patients I have ever known," he says. "She had undergone 50 cryoblocks over 30 years, which is unprecedented, and resulted in her referral to me when this proved too dangerous." © 2019 BBC

Keyword: Pain & Touch
Link ID: 26299 - Posted: 06.05.2019

By Cara Giaimo If you’ve ever taken a big bite of wasabi, you know what comes next: a painful zing that creeps over your whole scalp. You aren’t the only animal that feels this way. The condiment’s sinus-burning kick comes from a chemical compound called allyl isothiocyanate, or AITC, that actively damages proteins within cells. Flies and flatworms shun it, as do mice and wolf spiders. “Practically every animal you look at will avoid AITC,” said Gary Lewin, a molecular physiologist at the Max Delbrück Center for Molecular Medicine in Berlin. But there is one exception. In a paper published Thursday in Science, scientists including Dr. Lewin showed that the highveld mole rat, a rodent found in South Africa, is entirely impervious to the substance. The study “demonstrates the power of studying naturally occurring differences in pain sensitivity,” said Ewan St. John Smith, a neurobiologist at the University of Cambridge, who was not involved in the research. The work could eventually lead to more effective pain treatment in humans. The scientists didn’t originally set out to find a wasabi aficionado. They were simply hoping to compare how several mole rat species respond to things that cause pain. Years ago, Dr. Lewin and others discovered that naked mole rats — pink, bucktoothed creatures known for their uncanny longevity, insectlike social cultures and blasé attitude toward oxygen — aren’t sensitive to acid or capsaicin, the compound that gives peppers their burn. To see whether their close relatives shared these traits, they exposed nine species of mole rat to a few pain agents. The naked mole rats didn’t react well to AITC. Neither did most of the other species the group studied, including the humans administering the trials. © 2019 The New York Times Company

Keyword: Pain & Touch
Link ID: 26282 - Posted: 05.31.2019

By Jan Hoffman Opening statements in the country’s first trial over whether a pharmaceutical company is liable for the opioid crisis began as a battle between fire and ice: Lawyers for Oklahoma, a state brought to its knees by addiction and overdose deaths, heatedly accused Johnson & Johnson of creating a deadly demand for the drugs, while the company coolly responded that it had acted responsibly and lawfully in its quest to offer relief to chronic pain patients. The trial, heard by a judge without a jury but livestreamed to the public, is being closely watched not only by those affected by prescription opioid addiction, but also by lawyers in almost 1,900 similar federal and state cases nationwide. Two other defendants who manufacture opioids settled with Oklahoma — Purdue Pharma will pay $270 million, Teva Pharmaceuticals, $85 million — leaving only J & J on trial. The state directly confronted what many legal experts have predicted will be the highest hurdle in the case: connecting one manufacturer of opioids to the cascading harms wrought by the entire industry. J & J pushed back hard, arguing that the state itself looked the other way as its own drug review board and prescription monitoring program for years neglected to swoop down on sources of diverted opioids. In addition, it said, Oklahoma could not tie any death directly to the company’s products — Duragesic, a fentanyl patch, and Nucynta, an opioid pill it no longer makes. “You hear about pill mills,” said Larry D. Ottaway, the lead counsel for a J & J subsidiary, Janssen Pharmaceuticals. “You don’t hear about patch mills.” Indeed both sides introduced what are sure to be their signature earworms, themes that will be echoed throughout the trial, estimated to take about two months. © 2019 The New York Times Company

Keyword: Drug Abuse; Pain & Touch
Link ID: 26275 - Posted: 05.29.2019

By Jane E. Brody One of the most widely prescribed prescription drugs, gabapentin, is being taken by millions of patients despite little or no evidence that it can relieve their pain. In 2006, I wrote about gabapentin after discovering accidentally that it could counter hot flashes. The drug was initially approved 25 years ago to treat seizure disorders, but it is now commonly prescribed off-label to treat all kinds of pain, acute and chronic, in addition to hot flashes, chronic cough and a host of other medical problems. The F.D.A. approves a drug for specific uses and doses if the company demonstrates it is safe and effective for its intended uses, and its benefits outweigh any potential risks. Off-label means that a medical provider can legally prescribe any drug that has been approved by the Food and Drug Administration for any condition, not just the ones for which it was approved. This can leave patients at the mercy of what their doctors think is helpful. Thus, it can become a patient’s job to try to determine whether a medication prescribed off-label is both safe and effective for their particular condition. This is no easy task even for well-educated doctors, let alone for desperate patients in pain. Two doctors recently reviewed published evidence for the benefits and risks of off-label use of gabapentin (originally sold under the trade name Neurontin) and its brand-name cousin Lyrica (pregabalin) for treating all kinds of pain. (There is now also a third drug, gabapentin encarbil, sold as Horizant, approved only for restless leg syndrome and postherpetic neuralgia, which can follow a shingles outbreak.) © 2019 The New York Times Company

Keyword: Pain & Touch; Drug Abuse
Link ID: 26253 - Posted: 05.21.2019

Jon Hamilton When Sterling Witt was a teenager in Missouri, he was diagnosed with scoliosis. Before long, the curvature of his spine started causing chronic pain. It was "this low-grade kind of menacing pain that ran through my spine and mostly my lower back and my upper right shoulder blade and then even into my neck a little bit," Witt says. The pain was bad. But the feeling of helplessness it produced in him was even worse. "I felt like I was being attacked by this invisible enemy," Witt says. "It was nothing that I asked for, and I didn't even know how to battle it." So he channeled his frustration into music and art that depicted his pain. It was "a way I could express myself," he says. "It was liberating." Witt's experience is typical of how an unpleasant sensation can become something much more complicated, scientists say. "At its core, pain is just something that hurts or makes you say ouch," says Karen Davis, a senior scientist at the Krembil Brain Institute in Toronto. "Everything else is the outcome of the pain, how it then impacts your emotions, your feelings, your behaviors." The ouch part of pain begins when something — heat, certain chemicals or a mechanical force — activates special nerve endings called nociceptors. © 2019 npr

Keyword: Pain & Touch
Link ID: 26249 - Posted: 05.20.2019

By Gabrielle Emanuel and Katie Thomas BOSTON — A federal jury on Thursday found the top executives of Insys Therapeutics, a company that sold a fentanyl-based painkiller, guilty of racketeering charges in a rare criminal prosecution that blamed corporate officials for contributing to the nation’s opioid epidemic. The jury, after deliberating for 15 days, issued guilty verdicts against the company’s founder, the onetime billionaire John Kapoor, and four former executives, finding they had conspired to fuel sales of its highly potent drug, Subsys, by not only bribing doctors to prescribe their product but also by misleading insurers about patients’ need for the drug. The verdict against Insys executives is a sign of the accelerating effort to hold pharmaceutical and drug distribution companies and their executives and owners accountable in ways commensurate with the devastation wrought by the prescription opioid crisis. More than 200,000 people have overdosed on such drugs in the past two decades. Federal authorities last month for the first time filed felony drug trafficking charges against a major pharmaceutical distributor, Rochester Drug Cooperative, and two former executives, accusing them of shipping tens of millions of oxycodone pills and fentanyl products to pharmacies that were distributing drugs illegally. And the state attorneys general of Massachusetts and New York have recently sued not just Purdue Pharma, the maker of OxyContin, but also members of the Sackler family who own the company — and who have largely escaped personal legal penalties for the company’s role in the epidemic, culpability they deny. © 2019 The New York Times Company

Keyword: Drug Abuse; Pain & Touch
Link ID: 26209 - Posted: 05.04.2019

By Jane E. Brody I was packing up at the end of a family vacation in Florida when my back went into an excruciating spasm unrelieved by a fistful of pain medication. As my twin sons, then 8 years old, wheeled me through the airport, one of them suggested, “Mom, if you think about something else, it won’t hurt so much.” At the time, I failed to appreciate the wisdom of his advice. Now, four decades later, a sophisticated distraction technique is being used to help patients of all ages cope with pain, both acute and chronic. The method, called Virtual Reality Therapy, goes beyond simple distraction, as might result from watching television. Rather, it totally immerses the patient in an entertaining, relaxing, interactive environment that so occupies the brain, it has no room to process pain sensations at the same time. “It’s not just a distraction — it’s like an endogenous narcotic providing a physiological and chemical burst that causes you to feel good,” said Jeffrey I. Gold, director of the pediatric pain management clinic at Children’s Hospital Los Angeles. “It’s different from reading a book or playing with a toy. It’s a multisensory experience that engages a person’s attention on a much deeper level.” Virtual Reality Therapy is the new kid on the block for pain management, now gradually growing in use as the opioid epidemic continues to soar and the price of the needed equipment has plummeted. VR, as it is called, has been most widely and successfully used so far to help children and adults weather acute pain, as can accompany an IV insertion or debridement of burns. But it can also enhance the effectiveness of established techniques like physical therapy, hypnosis and cognitive behavioral therapy to treat debilitating chronic pain. © 2019 The New York Times Company

Keyword: Pain & Touch; Attention
Link ID: 26182 - Posted: 04.29.2019

Lisa Wehrstedt Researchers in Philadelphia revealed last week that tastebuds also bear odour-detecting proteins, calling into question the idea that smell and taste come together in the brain to produce flavour. According to Dr Mehmet Hakan Ozdener, his findings open up the possibility of using smells to trick us into healthier eating, for example by adding a low-concentration odour to food to make it taste sweeter and thereby reduce sugar intake. It is believed that we all experience a form of motion-induced blindness while driving at night, when the red lights of the cars in front temporarily disappear if we move our eyes to the oncoming traffic. This phenomenon, where the brain ignores or discards visual information when it is placed in front of a moving background, was first observed in the lab in 1965. First described in 1976, the McGurk effect is a connection between hearing and vision in speech perception. When the auditory component of a syllable is paired with the visual component of another, this can lead to the perception of a third sound. Research conducted by the University of Oxford in 2013 suggests that the sight of cutlery and the perception of its size, weight, shape and colour have an effect on how we determine flavour, suggesting that the brain makes judgments on food even before it goes in our mouths. Yoghurt, for example, tastes sweeter on a white spoon than it does on a black spoon. © 2019 Guardian News & Media Limited

Keyword: Chemical Senses (Smell & Taste); Vision
Link ID: 26180 - Posted: 04.29.2019

Jayne O'Donnell and Ken Alltucker, Doctors are misusing 2016 opioid pain medication guidelines, federal officials said Wednesday, a clear response to increasing complaints from chronic pain patients who say they are the victims of an overreaction to the opioid crisis. The Centers for Disease Control and Prevention, in new guidance for opioid prescribing, said many physicians were guilty of a "misapplication" of 2016 guidelines that clamped down on the use of opioids. The new guidelines, published in the New England Journal of Medicine, was the latest federal acknowledgement that many physicians' responses to the opioid crisis went too far. Former Food and Drug Administration commissioner Scott Gottlieb, a physician, spoke out last July about the impact the opioid crisis response had on pain patients when he called for development of more options. Until then, people in the middle of cancer treatments, having "acute sickle cell crises" or with pain after surgery shouldn't be affected by the earlier recommendations, CDC said. These patients were outside the scope of the guidelines, which were intended for primary care doctors treating chronic pain patients, CDC said. Doctors that set hard limits or cut off opioids are also misapplying the government's guidance, CDC said. Doctors should prescribe the lowest effective dosage and avoid increasing it to 90 "morphine milligram equivalents" a day or "carefully justify" any decision to raise the dose to that level.

Keyword: Pain & Touch; Drug Abuse
Link ID: 26173 - Posted: 04.25.2019

Yao-Hua Law When it comes to migration science, birds rule. Although many mammals — antelopes, whales, bats — migrate, too, scientists know far less about how those animals do it. But a new device, invented by animal navigation researcher Oliver Lindecke, could open a new way to test how far-ranging bats find their way. Lindecke, of Leibniz Institute for Zoo and Wildlife Research in Germany, has been studying bat migration since 2011. He started with analyzing different forms of hydrogen atoms in wild bats to infer where they had flown from. But figuring out how the bats knew where to go was trickier. Lindecke needed a field setup that let him test what possible cues from nature helped bats navigate across vast distances. The first step was studying in which direction the bats first take flight. Such experiments on birds typically involve confining the animals in small, enclosed spaces. But that doesn’t work for bats, which tend to fall asleep in such spaces. So he invented what he calls the circular release box: a flat-bottom, funnel-shaped container topped by a wider lid. To escape, the bat crawls up the wall and takes off from the edge. Bat tracks in a layer of chalk (Lindecke says he was inspired by a snow-covered Berlin street) indicate where the bat took off. In August 2017, Lindecke captured 54 soprano pipistrelle bats (Pipistrellus pygmaeus) in a large, 50-meter-wide trap at the Pape Ornithological Research Station in Latvia as the animals were migrating along the coast of the Baltic Sea toward Central Europe. Experiments with the new device showed that the adult bats flew straight in the direction in which they took off, Lindecke and colleagues report online March 1 in the Journal of Zoology. |© Society for Science & the Public 2000 - 2019

Keyword: Animal Migration
Link ID: 26159 - Posted: 04.20.2019

By Jamie Lauren Keiles When Jennifer Allen watched videos of space, she sometimes felt this peculiar sensation: a tingling that spread through her scalp as the camera pulled back to show the marble of the earth. It came in a wave, like a warm effervescence, making its way down the length of her spine and leaving behind a sense of gratitude and wholeness. Allen loved this feeling, but she didn’t know what caused it. It was totally distinct from anything she’d experienced before. Every two years or so she’d take to Google. She tried searching things like “tingling head and spine” or “brain orgasm.” For nine years, the search didn’t turn up anything. Then, around 2009, it did. As always, Allen typed her phrases into Google, but this time she got a result on a message board called SteadyHealth. The post was titled WEIRD SENSATION FEELS GOOD: i get this sensation sometimes. theres no real trigger for it. it just happens randomly. its been happening since i was a kid and i’m 21 now. some examples of what it seems has caused it to happen before are as a child while watching a puppet show and when i was being read a story to. as a teenager when a classmate did me a favor and when a friend drew on the palm of my hand with markers. sometimes it happens for no reason at all The poster went on to demand an explanation. In the discussion, nobody had one, but many described a similar feeling — a “silvery sparkle” inside the head, a euphoric “brain-gasm” or a feeling like goose bumps in the scalp that faded “in and out in waves of heightened intensity.” Many people agreed that the sensation was euphoric. (“Aside from an actual orgasm, it’s probably the most enjoyable sensation possible,” one user wrote.) Its triggers were as varied as watching someone fill out a form, listening to whispering sounds or seeing Bob Ross paint landscapes on TV. Allen scrolled through pages and pages of discussion. Oh my gosh, she remembers thinking. These people are talking about exactly what I experience. © 2019 The New York Times Company

Keyword: Pain & Touch; Hearing
Link ID: 26114 - Posted: 04.04.2019

By C. Claiborne Ray Q. How do bees find the flowers in the container garden on the fourth-floor deck of my city apartment? A. Foraging bees use the same methods to find nectar and pollen four floors up that they use at ground level. Honeybees routinely fly two miles from their hives in their search for raw material for honey; it doesn’t require much extra energy to fly several stories up. It takes only one scout to report a promising garden to the rest of the hive with a famous waggle dance. The scout relies on its sophisticated eyes, which are tuned to a variety of wavelengths, including ultraviolet color patterns in flowers that are invisible to people. We’re taking you on a journey to help you understand how bees, while hunting for pollen, use all of their senses — taste, touch, smell and more — to decide what to pick up and bring home. When the bees get closer to flowers, smell receptors begin transmitting information. And it has recently been discovered that both bumblebees and honeybees can detect and discriminate among weak electrostatic fields emanating from flowers. The bees accumulate a positive charge, while the flowers have a negative charge. The interaction between the fields is detected by antennae or sensitive hairs on the body. The electrical field helps bees to recognize pollen-rich blooms and perhaps even to transfer the pollen. © 2019 The New York Times Company

Keyword: Animal Migration; Animal Communication
Link ID: 26102 - Posted: 04.02.2019

By Heather Murphy An article this week about Jo Cameron, who has lived for 71 years without experiencing pain or anxiety because she has a rare genetic mutation, prompted questions from New York Times readers. The notion that the same gene could be responsible for the way a person processes physical and psychological pain left many perplexed: Aren’t they totally different? Or does her story hint that sensitivity to one type of pain might be intertwined with sensitivity to another? Childbirth, Ms. Cameron said, felt like “a tickle.” She often relies on her husband to alert her when she is bleeding, bruised or burned because nothing hurts. When someone close to her has died, she said, she has felt sad but “I don’t go to pieces.” She cannot recall ever having been riled by anything — even a recent car crash. On an anxiety disorder questionnaire, she scored zero out of 21. “I drive people mad by being cheerful,” she said. Here’s a bit about what’s known: Do those who live without pain also live without anxiety? No. Before encountering Ms. Cameron, the scientists who studied her case worked with other patients who did not experience pain. “Reduced anxiety has not really been noted before in the other pain insensitivity disorders we work on,” said Dr. James Cox, a senior lecturer from the Molecular Nociception Group at University College London. He also said that given Ms. Cameron had gone more than six decades without realizing just how unusual she was, there could be others like her. A number of such individuals contacted The Times after the article was published. © 2019 The New York Times Company

Keyword: Pain & Touch; Emotions
Link ID: 26100 - Posted: 04.01.2019

Ian Sample Science editor Doctors have identified a new mutation in a woman who is barely able to feel pain or stress after a surgeon who was baffled by her recovery from an operation referred her for genetic testing. Jo Cameron, 71, has a mutation in a previously unknown gene which scientists believe must play a major role in pain signalling, mood and memory. The discovery has boosted hopes of new treatments for chronic pain which affects millions of people globally. Cameron, a former teacher who lives in Inverness, has experienced broken limbs, cuts and burns, childbirth and numerous surgical operations with little or no need for pain relief. She sometimes leans on the Aga and knows about it not from the pain, but the smell. “I’m vegan, so the smell is pretty obvious,” she says. “There’s no other burning flesh going on in the house.” But it is not only an inability to sense pain that makes Cameron stand out: she also never panics. When a van driver ran her off the road two years ago, she climbed out of her car, which was on its roof in a ditch, and went to comfort the shaking young driver who cut across her. She only noticed her bruises later. She is relentlessly upbeat, and in stress and depression tests she scored zero. “I knew that I was happy-go-lucky, but it didn’t dawn on me that I was different,” she says. “I thought it was just me. I didn’t know anything strange was going on until I was 65.” © 2019 Guardian News & Media Limited

Keyword: Pain & Touch; Genes & Behavior
Link ID: 26090 - Posted: 03.28.2019

Amber Dance Robert Sorge was studying pain in mice in 2009, but he was the one who ended up with a headache. At McGill University in Montreal, Canada, Sorge was investigating how animals develop an extreme sensitivity to touch. To test for this response, Sorge poked the paws of mice using fine hairs, ones that wouldn’t ordinarily bother them. The males behaved as the scientific literature said they would: they yanked their paws back from even the finest of threads. But females remained stoic to Sorge’s gentle pokes and prods1. “It just didn’t work in the females,” recalls Sorge, now a behaviourist at the University of Alabama at Birmingham. “We couldn’t figure out why.” Sorge and his adviser at McGill University, pain researcher Jeffrey Mogil, would go on to determine that this kind of pain hypersensitivity results from remarkably different pathways in male and female mice, with distinct immune-cell types contributing to discomfort2. Sorge and Mogil would never have made their discovery if they had followed the conventions of most pain researchers. By including male and female mice, they were going against the crowd. At the time, many pain scientists worried that females’ hormone cycles would complicate results. Others stuck with males because, well, that’s how things were done. Today, inspired in part by Sorge and Mogil’s work and spurred on by funders, pain researchers are opening their eyes to the spectrum of responses across sexes. Results are starting to trickle out, and it’s clear that certain pain pathways vary considerably, with immune cells and hormones having key roles in differing responses. © 2019 Springer Nature Publishing AG

Keyword: Pain & Touch; Hormones & Behavior
Link ID: 26089 - Posted: 03.28.2019

Maria Temming A new analysis of people’s brain waves when surrounded by different magnetic fields suggests that people have a “sixth sense” for magnetism. Birds, fish and some other creatures can sense Earth’s magnetic field and use it for navigation (SN: 6/14/14, p. 10). Scientists have long wondered whether humans, too, boast this kind of magnetoreception. Now, by exposing people to an Earth-strength magnetic field pointed in different directions in the lab, researchers from the United States and Japan have discovered distinct brain wave patterns that occur in response to rotating the field in a certain way. These findings, reported in a study published online March 18 in eNeuro, offer evidence that people do subconsciously respond to Earth’s magnetic field — although it’s not yet clear exactly why or how our brains use this information. “The first impression when I read the [study] was like, ‘Wow, I cannot believe it!’” says Can Xie, a biophysicist at Peking University in Beijing. Previous tests of human magnetoreception have yielded inconclusive results. This new evidence “is one step forward for the magnetoreception field and probably a big step for the human magnetic sense,” he says. “I do hope we can see replications and further investigations in the near future.” During the experiment, 26 participants each sat with their eyes closed in a dark, quiet chamber lined with electrical coils. These coils manipulated the magnetic field inside the chamber such that it remained the same strength as Earth’s natural field but could be pointed in any direction. Participants wore an EEG cap that recorded the electrical activity of their brains while the surrounding magnetic field rotated in various directions. |© Society for Science & the Public 2000 - 2019

Keyword: Pain & Touch
Link ID: 26052 - Posted: 03.19.2019

By Haider Warraich The United States uses a third of the world’s opioids but a fifth of Americans still say they suffer from chronic pain. The only demonstrable effect of two decades of widespread prescription of opioids has been catastrophic harm. With more than 47,000 Americans dying of opioid overdoses in 2017 and hundreds of thousands more addicted to them, it was recently reported that, for the first time, Americans were more likely to die of opioids than of car accidents. This has forced many to take a step back and ponder the very nature of pain, to understand how best to alleviate it. The ancient Greeks considered pain a passion — an emotion rather than a sensation like touch or smell. During the Dark Ages in Europe, pain was seen as a punishment for sins, a spiritual and emotional experience alleviated through prayers rather than prescriptions. In the 19th century, the secularization of Western society led to the secularization of pain. It was no longer a passion to be endured but a sensation to be quashed. The concept of pain as a purely physical phenomenon reached its zenith in the 1990s, when medical organizations such as the American Pain Society and the Department of Veterans Affairs succeeded in having pain designated a “fifth vital sign,” alongside blood pressure, temperature and breathing and heart rate. This coincided with the release of long-acting opioids like OxyContin. Doctors believed they now had an effective remedy for their patients’ suffering. While opioids do help many patients with acute pain from injuries, surgeries or conditions like cancer, looking back it’s clear that using opioids to treat chronic pain — backaches, bum knees and the like — might well be considered the worst medical mistake of our era. © 2019 The New York Times Company

Keyword: Pain & Touch; Drug Abuse
Link ID: 26047 - Posted: 03.18.2019