Links for Keyword: Pain & Touch

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


Links 61 - 80 of 664

Cannabis makes pain more bearable rather than actually reducing it, a study from the University of Oxford suggests. Using brain imaging, researchers found that the psychoactive ingredient in cannabis reduced activity in a part of the brain linked to emotional aspects of pain. But the effect on the pain experienced varied greatly, they said. The researchers' findings are published in the journal Pain. The Oxford researchers recruited 12 healthy men to take part in their small study. Participants were given either a 15mg tablet of THC (delta-9-tetrahydrocannabinol) - the ingredient that is responsible for the high - or a placebo. The volunteers then had a cream rubbed into the skin of one leg to induce pain, which was either a dummy cream or a cream that contained chilli - which caused a burning and painful sensation. Each participant had four MRI scans which revealed how their brain activity changed when their perception of the pain reduced. Dr Michael Lee, lead study author from Oxford University's Centre for Functional Magnetic Resonance Imaging of the Brain, said: "We found that with THC, on average people didn't report any change in the burn, but the pain bothered them less." BBC © 2012

Related chapters from BP7e: 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: 17633 - Posted: 12.22.2012

By Liz Kowalczyk Health officials investigating the national fungal meningitis outbreak caused by tainted steroid injections had thought that the worst was over. The number of new cases was dwindling. Then came patients like Anna Adair. An avid gardener and dog-breeder, Adair was rolled into a Michigan emergency room in a wheelchair Nov. 15. She had been bedridden for days, and that morning a bolt of pain in her lower back had caused her to tumble to the bathroom floor. Doctors quickly reached a disturbing realization: An infection caused by black mold had infiltrated her spine, near where she had received an injection made by a Massachusetts pharmacy, and spread into the bone. It was not the ­meningitis that sickened hundreds of others in late summer and early fall, but part of a frightening second wave of ­fungal infections caused by contaminated drugs. Dozens more people have now been diagnosed with excruciating abscesses or inflamed nerves in their backs that are proving formidable to cure. In a health alert issued Thursday, the federal Centers for Disease Control and Prevention said it is worried that some patients with spinal infections may not even be aware of their condition because the symptoms mimic the very back pain they originally sought to treat with steroids. The agency is now recommending that doctors consider performing MRI scans to screen all patients who have persistent back pain and received steroids from one of three contaminated batches. Previously, it advised scanning just those with new or worsening pain. © 2012 NY Times Co.

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 17631 - Posted: 12.22.2012

By Scicurious I would like to start this post with a challenge. Can you get through this entire post WITHOUT feeling itchy? I know I couldn’t even write the first line. And I’m not alone. Itch is contagious. Watching someone else scratch can make you itch, and you should try to get through a lecture on a skin condition. I wonder how dermatologists can take it. What IS an itch? The clinical definition is that it’s an “unpleasant sensation associated with the urge to scratch”. Ok, then. Itching is a very important part of clinical diagnosis, from things like poison ivy to allergies to severe use of methamphetamine. In addition, there is a psychological disorder of severe itch which can be both disfiguring and incredibly distressing. But where does it come from and why do we itch? There’s an obvious evolutionary reason (OMG a spider on my arm getitoffgetitoffgetitioff!!!!), but what about social itch? We know about the neurobiological “itch matrix”, which involves areas of the brain associated with touch and somatosensory processing, the premotor areas (for scratching), the anterior insula, prefrontal cortex, thalamus, and cerebellum. From a combination of all of these areas (accompanied, of course, by other things like the visual areas to process seeing the spider on your hand), you get an itch and a scartching response, and other involved areas (like the insula and cingulate) may help make it unpleasant enough for you to want to deal with it. All of these areas are also associated with the processing of other stimuli, like touch and pain, which may contribute to the sensation of itch. © 2012 Scientific American,

Related chapters from BP7e: Chapter 9: Hearing, Vestibular Perception, Taste, and Smell; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 6: Hearing, Balance, Taste, and Smell; Chapter 14: Attention and Consciousness
Link ID: 17590 - Posted: 12.11.2012

By LISA SANDERS, M.D. On Thursday, we challenged Well readers to puzzle their way through the case of a 25-year-old elephant trainer who developed “the worst headache of his life.” The case was made more confusing by the fact that he had been head-butted by a zebra several years earlier. Turns out the zebra was a bit of a red herring – for the doctors at the time, and for many of you. The correct diagnosis is… Herpes zoster, commonly known as shingles The internist assigned to the case, Dr. Bilal Ahmed, was able to make the diagnosis because when he examined the patient the next day, he saw the characteristic zoster rash above the patient’s right eye that had developed overnight. Nearly 200 people wrote in with their thoughts on what Dr. Ahmed might have seen to reveal the diagnosis when he looked at the patient. The first person to guess the correct diagnosis was Lotty Fulkerson of Massachusetts, a licensed practical nurse who has seen a lot of zoster. It was the combination of the patient’s terrible pain and the fact that the doctor saw something that told him the diagnosis that made her think it was probably shingles. Only three other readers guessed correctly. Herpes zoster, also known as shingles, is caused by the re-emergence of the herpes virus that is the source of the childhood illness chickenpox. The term “shingles” comes from the Latin word “cingulum,” which means belt or girdle; the rash of herpes zoster often appears in a band or belt-like pattern. When the original chickenpox infection resolves, the virus doesn’t die but instead takes refuge in branches of the nerves just outside the spinal cord, where it will reside for decades. In up to a third of patients who have had chickenpox, it re-emerges, causing pain and a rash and sometimes more. Why these survivor viruses re-emerge is unclear, but it may be linked to a weakened immune system. Copyright 2012 The New York Times Company

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 17556 - Posted: 12.01.2012

By JUSTIN HECKERT The girl who feels no pain was in the kitchen, stirring ramen noodles, when the spoon slipped from her hand and dropped into the pot of boiling water. It was a school night; the TV was on in the living room, and her mother was folding clothes on the couch. Without thinking, Ashlyn Blocker reached her right hand in to retrieve the spoon, then took her hand out of the water and stood looking at it under the oven light. She walked a few steps to the sink and ran cold water over all her faded white scars, then called to her mother, “I just put my fingers in!” Her mother, Tara Blocker, dropped the clothes and rushed to her daughter’s side. “Oh, my lord!” she said — after 13 years, that same old fear — and then she got some ice and gently pressed it against her daughter’s hand, relieved that the burn wasn’t worse. “I showed her how to get another utensil and fish the spoon out,” Tara said with a weary laugh when she recounted the story to me two months later. “Another thing,” she said, “she’s starting to use flat irons for her hair, and those things get superhot.” Tara was sitting on the couch in a T-shirt printed with the words “Camp Painless But Hopeful.” Ashlyn was curled on the living-room carpet crocheting a purse from one of the skeins of yarn she keeps piled in her room. Her 10-year-old sister, Tristen, was in the leather recliner, asleep on top of their father, John Blocker, who stretched out there after work and was slowly falling asleep, too. The house smelled of the homemade macaroni and cheese they were going to have for dinner. A South Georgia rainstorm drummed the gutters, and lightning illuminated the batting cage and the pool in the backyard. Without lifting her eyes from the crochet hooks in her hands, Ashlyn spoke up to add one detail to her mother’s story. “I was just thinking, What did I just do?” she said. © 2012 The New York Times Company

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 17507 - Posted: 11.19.2012

Women with migraines did not appear to experience a decline in cognitive ability over time compared to those who didn’t have them, according to a nine-year follow up study funded by the National Institutes of Health. The study also showed that women with migraine had a higher likelihood of having brain changes that appeared as bright spots on magnetic resonance imaging (MRI), a type of imaging commonly used to evaluate tissues of the body. "The fact that there is no evidence of cognitive loss among these women is good news," said Linda Porter, Ph.D., pain health science policy advisor in the Office of the Director at the National Institute of Neurological Disorders and Stroke (NINDS), which provided funding for the study. "We’ve known for a while that women with migraine tend to have these brain changes as seen on MRI. This nine-year study is the first of its kind to provide long-term follow-up looking for associated risk." "An important message from the study is that there seems no need for more aggressive treatment or prevention of attacks," said Mark C. Kruit, M.D., Ph.D., one of the principal investigators, and a neuroradiologist from Leiden University Medical Center, the Netherlands, which led the study. Dr. Kruit and associates evaluated MRIs for changes in the white matter, brainstem, and cerebellum that appeared on the scans as bright spots known as hyperintensities. Previous studies have shown an association between such hyperintensities and risk factors for atherosclerotic disease, increased risk of stroke and cognitive decline.

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 14: Attention and Consciousness
Link ID: 17488 - Posted: 11.14.2012

by Greg Miller Seeing someone yawn or hearing someone laugh makes you likely to follow suit. The same goes for scratching an itch. Now, for the first time, researchers have investigated the neural basis of contagious itch, identifying several brain regions whose activity predicts how susceptible people are to feeling itchy when they see someone else scratch. Researchers in the United Kingdom showed volunteers video clips of people scratching an arm or a spot on their chest. Sure enough, subjects reported feeling more itchy, and most scratched themselves at least once during the experiment. When a subset of the volunteers watched the videos inside an functional magnetic resonance imaging scanner, the scans revealed activity in several of the same brain regions known to fire up in response to an itch-inducing histamine injection. Activity in three of these areas correlated with subjects' self-reported itchiness, the team reports online today in the Proceedings of the National Academy of Sciences. Personality tests suggest that the trait that best predicts susceptibility to contagious itch is neuroticism, not empathy, as some researchers have suggested. © 2010 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 11: Emotions, Aggression, and Stress
Link ID: 17484 - Posted: 11.13.2012

Why some people respond to treatments that have no active ingredients in them may be down to their genes, a study in the journal PLoS ONE suggests. The so-called "placebo effect" was examined in 104 patients with irritable bowel syndrome (IBS) in the US. Those with a particular version of the COMT gene saw an improvement in their health after placebo acupuncture. The scientists warn that while they hope their findings will be seen in other conditions, more work is needed. Edzard Ernst, a professor of complementary medicine at the University of Exeter, said: "This is a fascinating but very preliminary result. "It could solve the age-old question of why some individuals respond to placebo, while others do not. "And if so, it could impact importantly on clinical practice. "But we should be cautious - the study was small, we need independent replications, and we need to know whether the phenomenon applies just to IBS or to all diseases." Gene variants The placebo effect is when a patient experiences an improvement in their condition while undergoing an inert treatment such as taking a sugar pill or, in this case, placebo acupuncture, where the patient believes they are receiving acupuncture but a sham device prevents the needles going into their body. BBC © 2012

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 17416 - Posted: 10.24.2012

by Robert F. Service According to George Bernard Shaw: "The most intolerable pain is produced by prolonging the keenest pleasure." Not to be picky George, but actually both sensations result from the activity of a diverse family of proteins on the surface of cells. This year's Nobel Prize in chemistry was awarded to two Americans—Robert Lefkowitz of Duke University in Durham, North Carolina, and Brian Kobilka of Stanford University School of Medicine in Palo Alto, California—who revealed the inner workings of these proteins, which also orchestrate a variety of things such as the way we see, smell, taste, feel, and fight infections. The notion that a single family of proteins was responsible for so many different physiological processes was far from evident early on. One hint came at the end of the 19th century, when scientists studying the effects of the hormone adrenaline discovered that it had different effects in various parts of the body. It made heart rate and blood pressure increase, but it decreased digestive activity and caused pupils to relax. One idea was that proteins called receptors on different cells somehow captured adrenaline molecules and either ferried the hormone into cells or transferred a message inside to trigger a response. In the 1940s, an American biologist named Raymond Ahlquist made enough progress to conclude that there must be two types of adrenaline receptors, one that caused smooth muscle cells to contract, and the other that stimulated the heart. © 2010 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 5: The Sensorimotor System
Link ID: 17354 - Posted: 10.11.2012

By Katherine Harmon A bite from the black mamba snake (Dendroaspis polylepis) can kill an adult human within 20 minutes. But mixed in with that toxic venom is a new natural class of compound that could be used to help develop new painkillers. Named “mambalgins,” these peptides block acute and inflammatory pain in mice as well as morphine does, according to a new study. Researchers, led by Sylvie Diochot, of the Institute of Molecular and Cellular Pharmacology at Nice University, Sophia Antipolis in France, purified the peptides from the venom and profiled the compounds’ structure. They then were able to test the mambalgins in strains of mice with various genetic tweaks to their pain pathways. Diochot and her colleagues determined that the mambalgins work by blocking an as-yet untargeted set of neurological ion channels associated with pain signals. The findings were published online October 3 in Nature (Scientific American is part of Nature Publishing Group). As a bonus, mambalgins did not have the risky side effect of respiratory depression that morphine does. And the mice developed less tolerance to them over time than is typical with morphine. Experimenting with the newfound compounds should also help researchers learn more about the mechanisms that drive pain. As the researchers noted in their paper, “It is essential to understand pain better to develop new analgesics. The black mamba peptides discovered here have the potential to address both of these aims.” © 2012 Scientific American,

Related chapters from BP7e: 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: 17333 - Posted: 10.04.2012

By PAULINE W. CHEN, M.D. Recounting her father’s struggle with cancer was difficult for the young woman, even several years after his death. He’d endured first surgery and then chemotherapy and radiation, she told me, and the cancer had gone into remission. He was thrilled, but the aggressive treatment left him with chronic, debilitating pain. Once active, he struggled to get around in his own home. “It wasn’t the cancer that got him,” the daughter said. “It was the pain.” Her father had turned to all of his doctors, with little relief. His surgeon had looked at his operative wounds, pronounced them well healed, then stated that they were in no way responsible for his disability. Both his cancer doctor and his radiation doctor congratulated him on being in remission but then declined to prescribe pain medications since they were no longer treating him and couldn’t provide ongoing follow-up and dosing guidance. His primary care doctor listened intently to his descriptions of his limitations, but then prescribed only small amounts of pain meds that offered fleeting relief at best. “I’ll never forget what my father had to go through,” she said, weeping. “I wouldn’t wish this on anyone.” I wish I could have reassured her that her father’s case was unusual. Sadly, according to a new study in The Journal of Clinical Oncology, a significant percentage of cancer patients continue to suffer from pain as her father did. Copyright 2012 The New York Times Company

Related chapters from BP7e: 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: 17300 - Posted: 09.26.2012

By James Gallagher Health and science reporter, BBC News Up to a million people in the UK have "completely preventable" severe headaches caused by taking too many painkillers, doctors have said. They said some were trapped in a "vicious cycle" of taking pain relief, which then caused even more headaches. The warning came as part of the National Institute for Health and Clinical Excellence's (NICE) first guidelines for treating headaches. It is also recommending acupuncture in some circumstances. "Medication overuse headaches" feel the same as other common headaches or migraines. There is no definitive UK data on the incidence of the condition, but studies in other countries suggest 1-2% of people are affected, while the World Health Organization says figures closer to 5% have been reported. While painkillers would be many people's instant response, they could be making sufferers feel even worse. Prof Martin Underwood, from Warwick Medical School, who led the NICE panel, said: "This can end up getting into a vicious cycle where your headache gets worse, so you take more painkillers, so your headache gets worse and this just becomes worse and worse and worse. BBC © 2012

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 17277 - Posted: 09.19.2012

In May, my six-year-old daughter, Julia, smashed into our front door handle and got a deep, bloody gash in her forehead. We rushed her, head wrapped like a tiny mummy, to the medical center at MIT, where we generally go for pediatric care. Julia wept while the nurse cleaned and examined her lacerated skin. After a short exam, she sent us to the emergency department at Children’s Hospital Boston for stitches. “How bad is that, generally?” I asked, having never experienced suturing either for myself or my cautious, risk-averse, older daughter. “It can be traumatic,” the nurse said. Julia cried, “I don’t want stitches.” It’s a large needle, but Julia is too busy coloring to notice. So I braced myself for the worst: an endless wait and nerve-wracking bustle; screaming, germ-laden children and brusque, end-of-shift staff. But more than anything, I dreaded the inevitable pain in store for my small child with the deep cut. (I know, kids get banged up on the path to adulthood and some pain is unavoidable. Still, when bloody heads are involved, I tend to overreact.) Indeed, I was in full Mama Bear mode when into our exam room strode Dr. Baruch Krauss, the attending physician that evening. Copyright Trustees of Boston University

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 14: Attention and Consciousness
Link ID: 17276 - Posted: 09.19.2012

By Jorge Cham and Dwayne Godwin [Graphic novel format.] Dwayne Godwin is a neuroscientist at the Wake Forest University School of Medicine. Jorge Cham draws the comic strip Piled Higher and Deeper at www.phdcomics.com. © 2012 Scientific American,

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 17264 - Posted: 09.17.2012

Daniel Cressey Rabbits are the latest focus of work seeking to measure animal discomfort by assessing facial expressions. Researchers working with animals often find it difficult to scientifically assess when their study subjects are in pain. Traditional methods rely on after-the-fact measurements involving weight loss or food and water consumption, or on subjective judgements such as how an animal moves. In an attempt to make pain assessment more scientific, geneticist Jeffrey Mogil at McGill University in Montreal, Canada, and his colleagues developed the 'mouse grimace scale', which was published in Nature Methods1 in May 2010 (see 'Mice pull pained expressions'). The scale relies on the scoring of five ‘action units’ — such as narrowing of the eyes and bulging of the cheeks — between zero (not present) and two (obviously present), with the combined score indicating total pain. The scale rapidly caught on among veterinarians to assess post-operative pain. “I’m surprised how quickly it was adopted as a practical thing to use in real-time for animal care,” says Mogil. Matthew Leach, who researches animal welfare at Newcastle University, UK, and led the work in rabbits, has been working on facial expressions of pain in various animals since the original mouse grimace scale came out. "The only way you can alleviate pain is to be able to identify it, and to understand how much pain an animal is in," he says. "There is a broad interest in grimace scales,” he notes, adding that compared with traditional models, “I would argue it’s potentially better and faster in many circumstances”. © 2012 Nature Publishing Group

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 17238 - Posted: 09.10.2012

by Colin Barras ON THE face of it, the placebo effect makes no sense. Someone suffering from a low-level infection will recover just as nicely whether they take an active drug or a simple sugar pill. This suggests people are able to heal themselves unaided - so why wait for a sugar pill to prompt recovery? New evidence from a computer model offers a possible evolutionary explanation, and suggests that the immune system has an on-off switch controlled by the mind. It all starts with the observation that something similar to the placebo effect occurs in many animals, says Peter Trimmer, a biologist at the University of Bristol, UK. For instance, Siberian hamsters do little to fight an infection if the lights above their lab cage mimic the short days and long nights of winter. But changing the lighting pattern to give the impression of summer causes them to mount a full immune response. Likewise, those people who think they are taking a drug but are really receiving a placebo can have a response which is twice that of those who receive no pills (Annals of Family Medicine, doi.org/cckm8b). In Siberian hamsters and people, intervention creates a mental cue that kick-starts the immune response. There is a simple explanation, says Trimmer: the immune system is costly to run - so costly that a strong and sustained response could dangerously drain an animal's energy reserves. In other words, as long as the infection is not lethal, it pays to wait for a sign that fighting it will not endanger the animal in other ways. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: 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: 17231 - Posted: 09.07.2012

By Stephani Sutherland Ice cream headache is a familiar summertime sensation, but the pain's source has been mysterious until now. A team led by Jorge Serrador of Harvard Medical School produced brain scans of “second-by-second changes” in blood flow while subjects sipped iced water through a straw pressed against the roof of the mouth, which caused the brain's major artery to widen. “Blood flow changes actually preceded the pain” that subjects reported, Serrador says. As the vessel narrowed again, the discomfort ebbed. He suspects that the influx of blood is meant to protect the brain from extreme cold and that increased pressure inside the skull could cause the pain. Serrador presented the results at Experimental Biology 2012 in April in San Diego. © 2012 Scientific American

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 17205 - Posted: 08.27.2012

by Catherine de Lange A potential new treatment to prevent morphine addiction is at hand. Researchers have identified an immune receptor involved in addiction to the drug, and found a way to block this receptor without affecting pain relief. The discovery offers hope that morphine can be used to relieve pain without running the risk of addiction. Opioid drugs such as morphine are known to target opioid receptors in the central nervous system, which block pain signals to the brain and flood it with the "feel-good" chemical dopamine. This reward response is what makes opioids so addictive. Morphine is a widely used pain killer, but its addictiveness means it has to be administered with caution, and often cannot be used for protracted periods of chronic pain. Mark Hutchinson from the University of Adelaide, Australia, and colleagues have now discovered that as well as working through the central nervous system, opioid drugs like heroin and morphine trigger an immune response, which seems to boost their addictive effects. Blocking this immune response in animals inhibits their addiction. Hutchinson's team previously observed that opioids bind to TLR-4 – immune system receptors in the cell membrane – which are responsible for identifying foreign bodies. However, the team did not know how this binding affected the body. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: 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: 17169 - Posted: 08.15.2012

by Carol Cruzan Morton Migraines are a battle of the sexes that women might prefer not winning. Each year, roughly three times more women than men—up to 18% of all women—suffer from the debilitating headaches, as tallied by epidemiological surveys in Europe and the United States. A new brain imaging study may explain the divide: The brains of women with migraines appear to be built differently than those of their male counterparts. To conduct the study, researchers headed by David Borsook, a neurologist and neurobiologist of Boston Children’s Hospital and Harvard Medical School, recruited 44 men and women, half of whom were migraine sufferers. The women who had migraines rated them as being as intense as the men did, but they tended to find them more unpleasant. Borsook says the distinction is analogous to the loudness of fingernails scratching on a chalkboard versus the torment of hearing the sound. The team then scanned the brains of the volunteers. The researchers gathered two kinds of data sets, one that captured brain shapes and features, and one that measured brain activity. Female migraine sufferers showed slightly thicker gray matter in two regions: one, the posterior insula, is well-known in pain processing; the other, the precuneus, has been recently linked to migraines but is more widely known as a fundamental brain hub that may house a person's consciousness or sense of self. The other volunteers, including the male migraine sufferers, did not show this thickening. All of the scans were done when people did not have a migraine. To figure out what those structural changes meant, lead author Nasim Maleki, a medical physicist at Boston Children's Hospital and Harvard Medical School, returned to the MRI scans of only those men and women with episodic migraines. © 2010 American Association for the Advancement of Science.

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 8: Hormones and Sex
Link ID: 17160 - Posted: 08.14.2012

by Krystnell A. Storr Imagine feeling like you’re lifting a 50-kilogram weight just by pulling at thin air. That’s just one of the possible applications of new "smart fingertips" created by a team of nanoengineers. The electronic fingers mold to the shape of the hand, and so far the researchers have shown that they can transmit electric signals to the skin. The team hopes to one day incorporate the devices into a smart glove that creates virtual sensations, fooling the brain into feeling everything from texture to temperature. Scientists have already developed circuits that stimulate our sense of touch. Some are used in Braille readers that allow blind people to browse the Internet. The devices work by sending electric currents to receptors in the skin, which interpret them as real sensations. However, most of these circuits are built on flat, rigid surfaces that can’t bend, stretch, or fold, says Darren Lipomi, a nanoengineer at the University of California, San Diego, who was not involved in the new study. Hoping to create circuits with the flexibility of skin, materials scientist John Rogers of the University of Illinois, Urbana-Champaign, and colleagues cut up nanometer-sized strips of silicon; implanted thin, wavy strips of gold to conduct electricity; and mounted the entire circuit in a stretchable, spider web-type mesh of polymer as a support. They then embedded the circuit-polyimide structure onto a hollow tube of silicone that had been fashioned in the shape of a finger. Just like turning a sock inside out, the researchers flipped the structure so that the circuit, which was once on the outside of the tube, was on the inside where it could touch a finger placed against it. © 2010 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 17152 - Posted: 08.13.2012