Links for Keyword: Pain & Touch

Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.


Links 1 - 20 of 829

By Michael Price Expensive medications tend to make us feel better, even when they’re no different than cheap generics. But they can also make us feel worse, according to a new study. Researchers have found that we’re more likely to experience negative side effects when we take a drug we think is pricier—a flip side of the placebo effect known as the “nocebo” effect. The work could help doctors decide whether to recommend brand-name or generic drugs depending on each patient’s expectations. In the study, researchers asked 49 people to test out a purported anti-itch cream that, in reality, contained no active ingredient. Some got “Solestan® Creme,” a fake brand name in a sleek blue box designed to look like other expensive brands on the market. Others received “Imotadil-LeniPharma Creme”—another fake, this time housed in a chintzier orange box resembling those typically used for generic drugs. “I put a lot of effort into making the designs convincing,” says study leader Alexandra Tinnermann, a neuroscientist at University Medical Center Hamburg-Eppendorf in Germany. The researchers rubbed one of the two creams on the volunteers’ forearms and waited a few minutes for it soak in. They told the participants that the cream could cause increased sensitivity to pain—a known side effect of real medications called hyperalgesia. Then the scientists affixed a small device to the volunteers’ arms that delivered a brief flash of heat up to about 45°C (or 113°F). © 2017 American Association for the Advancement of Science.

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 24154 - Posted: 10.06.2017

By JANE E. BRODY If you’ve never had a migraine, I have two things to say to you: 1) You’re damn lucky. 2) You can’t begin to imagine how awful they are. I had migraines – three times a month, each lasting three days — starting from age 11 and finally ending at menopause. Although my migraines were not nearly as bad as those that afflict many other people, they took a toll on my work, family life and recreation. Atypically, they were not accompanied by nausea or neck pain, nor did I always have to retreat to a dark, soundless room and lie motionless until they abated. But they were not just “bad headaches” — the pain was life-disrupting, forcing me to remain as still as possible. Despite being the seventh leading cause of time spent disabled worldwide, migraine “has received relatively little attention as a major public health issue,” Dr. Andrew Charles, a California neurologist, wrote recently in The New England Journal of Medicine. It can begin in childhood, becoming more common in adolescence and peaking in prevalence at ages 35 to 39. It afflicts two to three times more women than men, and one woman in 25 has chronic migraines on more than 15 days a month. But while the focus has long been on head pain, migraines are not just pains in the head. They are a body-wide disorder that recent research has shown results from “an abnormal state of the nervous system involving multiple parts of the brain,” said Dr. Charles, of the U.C.L.A. Goldberg Migraine Program at the David Geffen School of Medicine in Los Angeles. He told me he hoped the journal article would educate practicing physicians, who learn little about migraines in medical school. Before it was possible to study brain function through a functional M.R.I. or PET scan, migraines were thought to be caused by swollen, throbbing blood vessels in the scalp, usually – though not always — affecting one side of the head. This classic migraine symptom prompted the use of medications that narrow blood vessels, drugs that help only some patients and are not safe for people with underlying heart disease. © 2017 The New York Times Company

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 24072 - Posted: 09.18.2017

By JANE E. BRODY Many years ago I was plagued with debilitating headaches associated with a number of seemingly unrelated activities that included cooking for company and sewing drapes for the house. I thought I might be allergic to natural gas or certain fabrics until one day I realized that I tensed my facial muscles when I concentrated intently on a project. The cure was surprisingly simple: I became aware of how my body was reacting and changed it through self-induced behavior modification. I consciously relaxed my muscles whenever I focused on a task that could precipitate a tension-induced headache. Fast-forward about five decades: Now it was my back that ached when I hurriedly cooked even a simple meal. And once again, after months of pain, I realized that I was transferring stress to the muscles of my back and had to learn to relax them, and to allow more time to complete a project to mitigate the stress. Happy to report, I recently prepared dinner for eight with nary a pain. I don’t mean to suggest that every ache and pain can be cured by self-awareness and changing one’s behavior. But recent research has demonstrated that the mind – along with other nonpharmacological remedies — can be powerful medicine to relieve many kinds of chronic or recurrent pains, especially low back pain. As Dr. James Campbell, a neurosurgeon and pain specialist, put it, “The best treatment for pain is right under our noses.” He suggests not “catastrophizing” – not assuming that the pain represents something disastrous that keeps you from leading the life you’ve chosen. Acute pain is nature’s warning signal that something is wrong that should be attended to. Chronic pain, however, is no longer a useful warning signal, yet it can lead to perpetual suffering if people remain afraid of it, the doctor said. © 2017 The New York Times Company

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 24053 - Posted: 09.11.2017

By Matt Reynolds Putting on a brave face won’t fool this algorithm. A new system that rates how much pain someone is in just by looking at their face could help doctors decide how to treat patients. By examining tiny facial expressions and calibrating the system to each person, it provides a level of objectivity in an area where that’s normally hard to come by. “These metrics might be useful in determining real pain from faked pain,” says Jeffrey Cohn at the University of Pittsburgh in the US. The system could make the difference between prescribing potentially addictive painkillers and catching out a faker. Objectively measuring pain levels is a tricky task, says Dianbo Liu, who created the system with his colleagues at the Massachusetts Institute of Technology. People experience and express pain differently, so a doctor’s estimate of a patient’s pain can often differ from a self-reported pain score. In an attempt to introduce some objectivity, Liu and his team trained an algorithm on videos of people wincing and grimacing in pain. Each video consisted of a person with shoulder pain, who had been asked to perform a different movement and then rate their pain levels. The result was an algorithm that can use subtle differences in facial expressions to inform a guess about how a given person is feeling. Certain parts of the face are particularly revealing, says Liu. Large amounts of movement around the nose and mouth tended to suggest higher self-reported pain scores. © Copyright New Scientist Ltd.

Related chapters from BN8e: Chapter 15: Emotions, Aggression, and Stress; Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 5: The Sensorimotor System
Link ID: 24026 - Posted: 09.02.2017

Laurel Hamers Scientists have traced the sensation of itch to a place you can’t scratch. The discomfort of a mosquito bite or an allergic reaction activates itch-sensitive nerve cells in the spinal cord. Those neurons talk to a structure near the base of the brain called the parabrachial nucleus, researchers report in the Aug. 18 Science. It’s a region that’s known to receive information about other sensations, such as pain and taste. The discovery gets researchers one step closer to finding out where itch signals ultimately end up. “The parabrachial nucleus is just the first relay center for [itch signals] going into the brain,” says study coauthor Yan-Gang Sun, a neuroscientist at the Chinese Academy of Sciences in Shanghai. Understanding the way these signals are processed by the brain could someday provide relief for people with chronic itch, Sun says. While the temporary itchiness of a bug bite is annoying, longer term, “uncontrollable scratching behavior can cause serious skin damage.” Previous studies have looked at the way an itch registers on the skin or how neurons convey those sensations to the spinal cord. But how those signals travel to the brain has been a trickier question, and this research is a “major step” toward answering it, says Zhou-Feng Chen, director of the Center for the Study of Itch at Washington University School of Medicine in St. Louis. |© Society for Science & the Public 2000 - 2017.

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23972 - Posted: 08.18.2017

Researchers from the National Institutes of Health have identified a class of sensory neurons (nerve cells that electrically send and receive messages between the body and brain) that can be activated by stimuli as precise as the pulling of a single hair. Understanding basic mechanisms underlying these different types of responses will be an important step toward the rational design of new approaches to pain therapy. The findings were published in the journal Neuron. “Scientists know that distinct types of neurons detect different types of sensations, such as touch, heat, cold, pain, pressure, and vibration,” noted Alexander Chesler, Ph.D., lead author of the study and principal investigator with the National Center for Complementary and Integrative Health’s (NCCIH) Division of Intramural Research (DIR). “But they know more about neurons involved with temperature and touch than those underlying mechanical pain, like anatomical pain related to specific postures or activities.” In this study, Chesler and his colleagues used a novel strategy that combined functional imaging (which measures neuronal activity), recordings of electrical activity in the brain, and genetics to see how neurons respond to various stimuli. The scientists focused on a class of sensory neurons that express a gene called Calca, as these neurons have a long history in pain research. The scientists applied various stimuli to the hairy skin of mice cheeks, including gentle mechanical stimuli (air puff, stroking, and brushing), “high-threshold” mechanical stimuli (hair pulling and skin pinching), and temperature stimulation. They found that the target neurons belong to two broad categories, both of which were insensitive to gentle stimulation. The first was a well-known type of pain fiber—a polymodal nociceptor—that responds to a host of high intensity stimuli such as heat and pinching. The second was a unique and previously unknown type of neuron that responded robustly to hair pulling. They called this previously undescribed class of high-threshold mechanoreceptors (HTMRs) “circ-HTMRs,” due to the unusual nerve terminals these neurons made in skin. They observed that the endings of the fibers made lasso-like structures around the base of each hair follicle.

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23970 - Posted: 08.17.2017

By DAVID C. ROBERTS Five years ago, I still lived a double life. I was 35, looking out over the Gulf of Thailand and a few weathered beach tenders. Inside, where dark suits filled the conference room, I could feel the eyes of my fellow diplomats. No doubt they were wondering why I was sitting on my briefcase. I joked to no one in particular “My nuclear codes,” trying to deflect awkwardness. The case actually concealed an orthotic sitting cushion that muffled the pain in my lower back; without it, silent shrieking was all I heard. Or maybe they had noticed I was the only one sweating. The air-conditioning tempered the tropical heat, but it was no match for the corset heat wrap that lay discreetly under my tailored suit. Over the previous decade I had become adept at hiding the unexplained pain that racked my back and joints. To all appearances, I was a fit 6-foot-3 man with an easy gait. No one in that conference room knew my suit pants disguised a lace-up ankle brace and a strap velcroed around my left knee. Nor did they know that during breaks I would sneak back to my hotel room where my wife, an artist who moonlighted as my one-person pit crew, waited to press my quadratus lumborum muscle back into submission. I lasted through that meeting as I had through countless others. But in the months that followed, sitting and walking became increasingly difficult. I started to stand during meetings, avoid plane travel, and take motorcycle taxis to go just a couple of buildings’ distance. Eventually, I let the doctors at the embassy in on my secret. They deemed me unfit for work and medevac’ed me from Bangkok back to the United States for treatment. I left quickly, without awkward explanations or goodbyes. © 2017 The New York Times Company

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23908 - Posted: 08.02.2017

Ashlie Stevens Ah, the brain freeze — the signature pain of summer experienced by anyone who has eaten an ice cream cone with too much enthusiasm or slurped down a slushie a little too quickly. But have you ever stopped mid-freeze to think about why our bodies react like this? Well, researchers who study pain have, and some, like Dr. Kris Rau of the University of Louisville in Kentucky, say it's a good way to understand the basics of how we process damaging stimuli. But first, a lesson in terminology. "There's a scientific medical term for ice cream headaches which is sphenopalatine ganglion neuralgia," Rau says. Try breaking that out at your next ice cream social. Anyway, to understand how brain freeze happens, it helps to think of your body and brain as a big computer where everything is hooked together. In this case, you see an ice cream truck. You get some ice cream. And then your brain gives you the go-ahead and you dive face-first into a double-scoop of mint chocolate chip. "Now on the roof of your mouth there are a lot of little blood vessels, capillaries," Rau says. "And there's a lot of nerve fibers called nociceptors that detect painful or noxious stimuli." The rush of cold causes those vessels to constrict. "And when that happens, it happens so quickly that all of those little pain fibers in the roof of your mouth — they interpret that as being a painful stimulus," Rau says. A message is then shot up to your brain via the trigeminal nerve, one of the major nerves of the facial area. The brain itself doesn't have any pain sensing fibers, but its covering — called the meninges — does. © 2017 npr

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23901 - Posted: 08.01.2017

By Natalie Grover (Reuters) - A handful of drugmakers are taking their first steps toward developing marijuana-based painkillers, alternatives to opioids that have led to widespread abuse and caused the U.S. health regulator to ask for a withdrawal of a popular drug this month. The cannabis plant has been used for decades to manage pain and there are increasingly sophisticated marijuana products available across 29 U.S. states, as well as in the District of Columbia, where medical marijuana is legal. There are no U.S. Food and Drug Administration (FDA)-approved painkillers derived from marijuana, but companies such as Axim Biotechnologies Inc, Nemus Bioscience Inc and Intec Pharma Ltd have drugs in various stages of development. The companies are targeting the more than 100 million Americans who suffer from chronic pain, and are dependent on opioid painkillers such as Vicodin, or addicted to street opiates including heroin. Opioid overdose, which claimed celebrities including Prince and Heath Ledger as victims, contributed to more than 33,000 deaths in 2015, according to the Centers for Disease Control and Prevention. Earlier this month, the FDA asked Endo International Plc to withdraw its Opana ER painkiller from the market, the first time the agency has called for the removal of an opioid painkiller for public health reasons. The FDA concluded that the drug's benefits no longer outweighed its risks. Multiple studies have shown that pro-medical marijuana states have reported fewer opiate deaths and there are no deaths related to marijuana overdose on record.(http://reut.rs/2r74Sbe) © 2017 Scientific American

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 23774 - Posted: 06.26.2017

By Matthew Hutson The life of a sheep is not as cushy as it looks. They suffer injury and infection, and can’t tell their human handlers when they’re in pain. Recently, veterinarians have developed a protocol for estimating the pain a sheep is in from its facial expressions, but humans apply it inconsistently, and manual ratings are time-consuming. Computer scientists at the University of Cambridge in the United Kingdom have stepped in to automate the task. They started by listing several “facial action units” (AUs) associated with different levels of pain, drawing on the Sheep Pain Facial Expression Scale. They manually labeled these AUs—nostril deformation, rotation of each ear, and narrowing of each eye—in 480 photos of sheep. Then they trained a machine-learning algorithm by feeding it 90% of the photos and their labels, and tested the algorithm on the remaining 10%. The program’s average accuracy at identifying the AUs was 67%, about as accurate as the average human, the researchers will report today at the IEEE International Conference on Automatic Face and Gesture Recognition in Washington, D.C. Ears were the most telling cue. Refining the training procedure further boosted accuracy. Given additional labeled images, the scientists expect their method would also work with other animals. Better diagnosis of pain could lead to quicker treatment. © 2017 American Association for the Advancement of Science. A

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23694 - Posted: 06.02.2017

Laurel Hamers Last year, Joan Peay slipped on her garage steps and smashed her knee on the welcome mat. Peay, 77, is no stranger to pain. The Tennessee retiree has had 17 surgeries in the last 35 years — knee replacements, hip replacements, back surgery. She even survived a 2012 fungal meningitis outbreak that sickened her and hundreds of others, and killed 64. This knee injury, though, “hurt like the dickens.” When she asked her longtime doctor for something stronger than ibuprofen to manage the pain, he treated her like a criminal, Peay says. His response was frustrating: “He’s known me for nine years, and I’ve never asked him for pain medicine other than what’s needed after surgery,” she says. She received nothing stronger than over-the-counter remedies. A year after the fall, she still lives in constant pain. Just five years ago, Peay might have been handed a bottle of opioid painkillers for her knee. After all, opioids — including codeine, morphine and oxycodone — are some of the most powerful tools available to stop pain. Hitting opioid receptors in the peripheral nervous system keeps pain messages from reaching the brain. But opioids can cause problems by overstimulating the brain’s reward system and binding to receptors in the brain stem and gut. But an opioid addiction epidemic spreading across the United States has soured some doctors on the drugs. Many are justifiably concerned that patients will get hooked or share their pain pills with friends and family. And even short-term users risk dangerous side effects: The drugs slow breathing and can cause constipation, nausea and vomiting. |© Society for Science & the Public 2000 - 2017

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 23686 - Posted: 05.31.2017

Patients who are told their medication can have certain side-effects may report these symptoms more often than patients who aren't aware their treatment carries these risks, a study of popular cholesterol pills suggests. Researchers focused on what they dubbed the "nocebo" effect, or the potential for people to complain of treatment-related side-effects when they think they're taking a specific drug but are actually given a placebo, or dummy pill, without any active ingredients. "It has been recognized for many years that when patients are warned about possible adverse reactions to a drug, they are much more likely to complain of these side effects than when they are unaware of the possibility that such side-effects might occur," said senior study author Dr. Peter Sever, a researcher at Imperial College London. To test this "nocebo" effect, researchers first randomly assigned about 10,000 trial participants in the UK, Ireland and Scandinavia to take either a statin pill to lower cholesterol or a placebo, then followed people for around three years to see how often they complained of four known statin side-effects: Patients on statins and on placebo pills reported similar rates of muscle aches and erectile dysfunction, the study found. People taking placebo also reported higher rates of sleep difficulties than patients on statins. ©2017 CBC/Radio-Canada.

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23665 - Posted: 05.27.2017

By Roman Liepelt and Jack Brooks An amputee struggles to use his new prosthetic limb. A patient with a frontal-lobe brain lesion insists that her left hand has a mind of its own. The alleged criminal claims in court that he did not fire the gun, even though several eyewitnesses watched him do it. Each of these individuals is grappling with two elements of the mind-body connection: ownership, or an ability to separate ourselves from the physical and social environments, and agency, a conviction that we have control over our limbs. We are quick to investigate a sticker placed on our forehead when looking in a mirror, recognizing the foreign object as abnormal. The human brain typically handles these phenomena by comparing neural signals encoding the intended action with those signals carrying sensory feedback. When we are born, we make erratic reaching and kicking movements to map our body and to calibrate our sensorimotor system. During infancy, these movements solidify our self-awareness, and around the time we first walk, we are quick to investigate a sticker placed on our forehead when looking in a mirror, recognizing the foreign object as abnormal. By the age of four, our brains are proficient at distinguishing self and other. In the amputee, the brain lesion patient, and the defendant on trial, the sense of self is disrupted due to discordance between sensory feedback from the limb and the brain’s expectations of how a movement should feel. © 1986-2017 The Scientist

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23625 - Posted: 05.17.2017

By Moheb Costandi Pain in infants is heartbreaking for new parents, and extremely difficult to treat effectively—if at all. Every year an estimated 15 million babies are born prematurely, most of whom will then undergo numerous lifesaving but painful procedures, such as heel pricking or insertion of a thin tube known as a cannula to deliver fluids or medicine. Preterm babies in the intensive care unit are subjected to an average of 11 such “skin-breaking” procedures per day, but analgesia is only used just over one third of the time. We know that repetitive, painful procedures in early infancy can impact brain development negatively—so why is pain in infants so undertreated? One reason is the lack of standard guidelines for administering the drugs. Some analgesics given to adults are unsuitable for infants, and those that can be used often have different effects in children, making dosing a problem. What is more, newborn babies are incapable of telling us how they feel, making it impossible to determine how effective any painkiller might be. Researchers at the University of Oxford may now have overcome this latter challenge, however. They report May 3 in Science Translational Medicine having identified a pain-related brain wave signal that responds to analgesics, and could be used to measure the drugs’ efficacy. Until as recently as the 1980s, it was assumed that newborn babies do not feel pain, and that giving them analgesics would do more harm than good. Although these misconceptions have been cleared up, we still have very little understanding of infant pain, and so treating it is a huge challenge for clinicians. © 2017 Scientific American

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 13: Memory, Learning, and Development
Link ID: 23576 - Posted: 05.05.2017

Laura Sanders An electrode on top of a newborn’s scalp, near the soft spot, can measure when the baby feels pain. The method, described online May 3 in Science Translational Medicine, isn’t foolproof, but it brings scientists closer to being able to tell when infants are in distress. Pain assessment in babies is both difficult and extremely important for the same reason: Babies don’t talk. That makes it hard to tell when they are in pain, and it also means that their pain can be more easily overlooked, says Carlo Bellieni, a pediatric pain researcher at the University Hospital Siena in Italy. Doctors rely on a combination of clues such as crying, wiggling and facial grimacing to guess whether a baby is hurting. But these clues can mislead. “Similar behaviors occur when infants are not in pain, for example if they are hungry or want a cuddle,” says study coauthor Rebeccah Slater of the University of Oxford. By relying on brain activity, the new method promises to be a more objective measurement. Slater and colleagues measured brain activity in 18 newborns between 2 and 5 days old. Electroencephalography (EEG) recordings from electrodes on the scalp picked up collective nerve cell activity as babies received a heel lance to draw blood or a low-intensity bop on the foot, a touch that’s a bit like being gently poked with a blunt pencil. One electrode in particular, called the Cz electrode and perched on the top of the head, detected a telltale neural spike between 400 and 700 milliseconds after the painful event. This brain response wasn’t observed when these same babies received a sham heel lance or an innocuous touch on the heel. |© Society for Science & the Public 2000 - 2017

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 13: Memory, Learning, and Development
Link ID: 23566 - Posted: 05.04.2017

Amber Dance Biologist Leo Smith held an unusual job while an undergraduate student in San Diego. Twice a year, he tagged along on a chartered boat with elderly passengers. The group needed him to identify two particular species of rockfish, the chilipepper rockfish and the California shortspine thornyhead. Once he’d found the red-orange creatures, the passengers would stab themselves in the arms with the fishes’ spines. Doing so, the seniors believed, would relieve their aching arthritic joints. Smith, now at the University of Kansas in Lawrence, didn’t think much of the practice at the time, but now he wonders if those passengers were on to something. Though there’s no evidence that anything in rockfish venom can alleviate pain — most fish stings are, in fact, quite painful themselves — some scientists suspect fish venom is worth a look. Studying the way venom molecules from diverse fishes inflict pain might help researchers understand how nerve cells sense pain and lead to novel ways to dull the sensation. Smith is one of a handful of scientists who are studying fish venoms, and there’s plenty to investigate. An estimated 7 to 9 percent of fishes, close to 3,000 species, are venomous, Smith’s work suggests. Venomous fishes are found in freshwater and saltwater, including some stingrays, catfishes and stonefishes. Some, such as certain fang blennies, are favorites in home aquariums. Yet stinging fishes haven’t gotten the same attention from scientists as snakes and other venomous creatures. |© Society for Science & the Public 2000 - 2017

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23515 - Posted: 04.20.2017

By STEPH YIN It’s a small fish, only a couple of inches long, and its bright colors make it pop in the Pacific coral reefs it calls home. The first thing that makes this fish peculiar is the striking pair of large lower canines it sports. But when attacked by a predator, this fish, part of a group called fang blennies,does something even more strange. A predator that puts this fang blenny in its mouth would experience a “violent quivering of the head,” according to George Losey, a zoologist who observed this species up close in a series of feeding experiments in the 1970s. Then the predator would open its jaws and gills. The little blenny would swim away, unscathed. A study published on Thursday in Current Biology now lays bare the details of the fish’s unusual defense mechanism: Unlike most venomous fish, which inject toxins through their fins, fang blennies deliver venom through their bite. Furthermore, fang blenny venom does not appear to produce potent pain, at least in mice. Instead, it causes a sudden drop in blood pressure, which might temporarily stupefy predators. “This is one of the most in-depth studies of how venom functions in any particular group of fish,” said Matthew Davis, an assistant professor of biology at St. Cloud State University in Minnesota, who did not participate in the research. A CT scan of Meiacanthus grammistes, a venomous fang blenny species. Anthony Romilio The authors of the study took a multipronged approach to studying venomous fang blennies. First, they imaged the jaws of fang blennies collected from around the Pacific and Indian Oceans to confirm what scientists long suspected: Not all fang blennies have venom glands at the base of their teeth. © 2017 The New York Times Company

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 23432 - Posted: 03.31.2017

by Laura Sanders Many babies born early spend extra time in the hospital, receiving the care of dedicated teams of doctors and nurses. For these babies, the hospital is their first home. And early experiences there, from lights to sounds to touches, may influence how babies develop. Touches early in life in the NICU, both pleasant and not, may shape how a baby’s brain responds to gentle touches later, a new study suggests. The results, published online March 16 in Current Biology, draw attention to the importance of touch, both in type and number. Young babies can’t see that well. But the sense of touch develops early, making it a prime way to get messages to fuzzy-eyed, pre-verbal babies. “We focused on touch because it really is some of the basis for communication between parents and child,” says study coauthor Nathalie Maitre, a neonatologist and neuroscientist at Nationwide Children’s Hospital in Columbus, Ohio. Maitre and her colleagues studied how babies’ brains responded to a light puff of air on the palms of their hands — a “very gentle and very weak touch,” she says. They measured these responses by putting adorable, tiny electroencephalogram, or EEG, caps on the babies. The researchers puffed babies’ hands shortly before they were sent home. Sixty-one of the babies were born early, from 24 to 36 weeks gestation. At the time of the puff experiment, they had already spent a median of 28 days in the hospital. Another group of 55 babies, born full-term, was tested in the three days after birth. |© Society for Science & the Public 2000 - 2017

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 13: Memory, Learning, and Development
Link ID: 23398 - Posted: 03.23.2017

By Jia Naqvi A drug frequently prescribed for pain is no more effective than a placebo at controlling sciatica, a common source of pain in the lower back and leg, according to a study published Wednesday in the New England Journal of Medicine. The researchers at the George Institute for Global Health in Australia followed 209 sciatica patients in Sydney who were randomly assigned to receive either the drug pregabalin, more commonly known as Lyrica, or a placebo. The results showed no significant differences in leg pain intensity between the group on the placebo and that on Lyrica after eight weeks taking the drug or during the rest of the year on follow-up exams. Similarly, there were no differences for other outcomes such as back pain, quality of life and degree of disability. After Lyrica was approved in 2004, it has become the most commonly prescribed medicine for neuropathic pain, which is caused by damage to the nervous system. The drug was ranked as the 19th-highest-earning pharmaceutical in 2015, with worldwide sales rising annually at a rate of 9 percent and sale revenue of more than $3 billion in 2015 in the United States. “We have seen a huge rise in the amount of prescriptions being written each year for patients suffering from sciatica. It’s an incredibly painful and disabling condition, so it’s no wonder people are desperate for relief and medicines such as pregabalin have been widely prescribed,” Christine Lin, one of the authors of the study and an associate professor at the George Institute for Global Health, said in a news release. © 1996-2017 The Washington Post

Related chapters from BN8e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23395 - Posted: 03.23.2017

By Daniel Barron It was 4 P.M., and Andrew* had just bought 10 bags of heroin. In his kitchen, he tugged one credit-card-sized bag from the rubber-banded bundle and laid it on the counter with sacramental reverence. Pain shot through his body as he pulled a cutting board from the cabinet. Slowly, deliberately, he tapped the bag's white contents onto the board and crushed it with the flat edge of a butter knife, forming a line of fine white powder. He snorted it in one pass and shuffled back to his armchair. It was bitter, but snorting heroin was safer than injecting, and he was desperate: his prescription pain medication was gone. I met Andrew the next day in the emergency room, where he told me about the previous day's act of desperation. I admitted him to control his swelling legs and joint pain. He was also detoxing from opioids. Andrew looked older than his 69 years. His face was wrinkled with exhaustion. A frayed, tangled mop of grizzled hair fell to his shoulders. Andrew had been a satellite network engineer, first for the military, more recently for a major telecommunications company. An articulate, soft-spoken fellow, he summed up his (rather impressive) career modestly: “Well, I'd just find where a problem was and then find a way to fix it.” Yet there was one problem he couldn't fix. “Doctor, I'm always in the most terrible pain,” he said, with closed eyes. “I had no other options. I started using heroin, bought it from my neighbor to help with the pain. I'm scared stiff.” © 2017 Scientific American

Related chapters from BN8e: Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology; Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology; Chapter 5: The Sensorimotor System
Link ID: 23378 - Posted: 03.20.2017