They now believe it to be a different order of sensation. Credit Photograph by Gerald Slota. Writing is the painting of a picture in another person’s mind using only words. The magnificent scenery of Texas has inspired many artists and writers through the years, and the backdrop of overwhelming beauty and sometimes.It was still shocking to M. She had graduated from Boston College with a degree in psychology, married at twenty- five, and had two children, a son and a daughter. She and her family settled in a town on Massachusetts. She worked for thirteen years in health care, becoming the director of a residence program for men who. But she and her husband began fighting. Help Me Understand Genetics. Help Me Understand Genetics provides an introduction to fundamental topics related to human genetics, including illustrations and basic explanations of genetics concepts. By the time she was thirty- two, her marriage had disintegrated. In the divorce, she lost possession of their home, and, amid her financial and psychological struggles, she saw that she was losing her children, too. Within a few years, she was drinking. She began dating someone, and they drank together. After a while, he brought some drugs home, and she tried them. Norway’s recent decision to destroy 70% of its tiny endangered population of wolves shocked conservationists worldwide and saw 35,000 sign a local petition. But in a region dominated by sheep farming support for the cull. The speedy physical and psychological changes that children undergo from birth through adolescence often leave parents wondering how best to care for them at each stage. PT's experts weigh in on topics such how to talk so kids. National School of Drama to get regional centres NEW DELHI - Union Minister of Culture Kumari Selja Tuesday said her ministry was working on a proposal to set up five new regional centres of the prestigious National School of. TurboBit.net provides unlimited and fast file cloud storage that enables you to securely share and access files online. New Diabetes Drugs Treatment Diabetes & Alternative Diabetes Treatment View the latest travel news, travel tips and world travel headlines on CNN.com. Eventually, they were doing heroin, which turned out to be readily available from a street dealer a block away from her apartment. One day, she went to see a doctor because she wasn. She had to leave her job. She lost visiting rights with her children. And she developed complications from the H. I. V., including shingles, which caused painful, blistering sores across her scalp and forehead. With treatment, though, her H. I. V. At thirty- six, she entered rehab, dropped the boyfriend, and kicked the drugs. She had two good, quiet years in which she began rebuilding her life. Then she got the itch. It was right after a shingles episode. The blisters and the pain responded, as they usually did, to acyclovir, an antiviral medication. But this time the area of the scalp that was involved became numb, and the pain was replaced by a constant, relentless itch. She felt it mainly on the right side of her head. It crawled along her scalp, and no matter how much she scratched it would not go away. And it took over her life just as she was starting to get it back. Her internist didn. Itching is an extraordinarily common symptom. All kinds of dermatological conditions can cause it: allergic reactions, bacterial or fungal infections, skin cancer, psoriasis, dandruff, scabies, lice, poison ivy, sun damage, or just dry skin. Creams and makeup can cause itch, too. And when the doctor examined M. All she saw was scratch marks. The internist prescribed a medicated cream, but it didn. The urge to scratch was unceasing and irresistible. I guess I would scratch when I was asleep, because in the morning there would be blood on my pillowcase. She returned to her internist again and again. But nothing the internist tried worked, and she began to suspect that the itch had nothing to do with M. Jeffrey Bernhard, a dermatologist with the University of Massachusetts Medical School, is among the few doctors to study itching systematically (he published the definitive textbook on the subject), and he told me of cases caused by hyperthyroidism, iron deficiency, liver disease, and cancers like Hodgkin. Sometimes the syndrome is very specific. Persistent outer- arm itching that worsens in sunlight is known as brachioradial pruritus, and it. Aquagenic pruritus is recurrent, intense, diffuse itching upon getting out of a bath or shower, and although no one knows the mechanism, it. Her viral count showed that the H. I. V. Additional blood tests and X- rays were normal. So the internist concluded that M. All sorts of psychiatric conditions can cause itching. Patients with psychosis can have cutaneous delusions. Severe stress and other emotional experiences can also give rise to a physical symptom like itching. Her life had been a mess, after all. But the antidepressant medications often prescribed for O. C. D. She simply felt itchy, on the area of her scalp that was left numb from the shingles. Although she could sometimes distract herself from it. The only thing that came close to offering relief was to scratch. At a later office visit, her doctor found a silver- dollar- size patch of scalp where skin had been replaced by scab. But her fingernails would always find a way to her flesh, especially while she slept. One morning, after she was awakened by her bedside alarm, she sat up and, she recalled, . The doctor looked closely at the wound. She shined a light on it and in M. Then she walked out of the room and called an ambulance. Only in the Emergency Department at Massachusetts General Hospital, after the doctors started swarming, and one told her she needed surgery now, did M. She had scratched through her skull during the night. The definition offered by the German physician Samuel Hafenreffer in 1. An unpleasant sensation that provokes the desire to scratch. Itch has been ranked, by scientific and artistic observers alike, among the most distressing physical sensations one can experience. Dermatologists call this the itch- scratch cycle. Scientists believe that itch, and the accompanying scratch reflex, evolved in order to protect us from insects and clinging plant toxins. The theory goes a long way toward explaining why itch is so exquisitely tuned. You can spend all day without noticing the feel of your shirt collar on your neck, and yet a single stray thread poking out, or a louse. For most of medical history, scientists thought that itching was merely a weak form of pain. Then, in 1. 98. 7, the German researcher H. Handwerker and his colleagues used mild electric pulses to drive histamine, an itch- producing substance that the body releases during allergic reactions, into the skin of volunteers. As the researchers increased the dose of histamine, they found that they were able to increase the intensity of itch the volunteers reported, from the barely appreciable to the . The scientists concluded that itch and pain are entirely separate sensations, transmitted along different pathways. Despite centuries spent mapping the body. But now the hunt was on, and a group of Swedish and German researchers embarked upon a series of tricky experiments. They inserted ultra- thin metal electrodes into the skin of paid volunteers, and wiggled them around until they picked up electrical signals from a single nerve fibre. Computers subtracted the noise from other nerve fibres crossing through the region. The researchers would then spend hours. Mostly, they encountered well- known types of nerve fibres that respond to temperature or light touch or mechanical pressure. When they introduced a tiny dose of histamine into the skin, however, they observed a sharp electrical response in some of these nerve fibres, and the volunteer would experience an itch. They announced their discovery in a 1. The fibres also turned out to have extraordinarily low conduction speeds, which explained why itchiness is so slow to build and so slow to subside. Other researchers traced these fibres to the spinal cord and all the way to the brain. Examining functional PET- scan studies in healthy human subjects who had been given mosquito- bite- like histamine injections, they found a distinct signature of itch activity. Several specific areas of the brain light up: the part of the cortex that tells you where on your body the sensation occurs; the region that governs your emotional responses, reflecting the disagreeable nature of itch; and the limbic and motor areas that process irresistible urges (such as the urge to use drugs, among the addicted, or to overeat, among the obese), reflecting the ferocious impulse to scratch. Now various phenomena became clear. Itch, it turns out, is indeed inseparable from the desire to scratch. It can be triggered chemically (by the saliva injected when a mosquito bites, say) or mechanically (from the mosquito. The itch- scratch reflex activates higher levels of your brain than the spinal- cord- level reflex that makes you pull your hand away from a flame. Brain scans also show that scratching diminishes activity in brain areas associated with unpleasant sensations. But some basic features of itch remained unexplained. On the one hand, our bodies are studded with receptors for itch, as they are with receptors for touch, pain, and other sensations; this provides an alarm system for harm and allows us to safely navigate the world. But why does a feather brushed across the skin sometimes itch and at other times tickle? But simply writing about a tick crawling up the nape of one. And then this one little spot along my flank where I. In one study, a German professor of psychosomatics gave a lecture that included, in the first half, a series of what might be called itchy slides, showing fleas, lice, people scratching, and the like, and, in the second half, more benign slides, with pictures of soft down, baby skin, bathers. Video cameras recorded the audience. Sure enough, the frequency of scratching among people in the audience increased markedly during the first half and decreased during the second. Thoughts made them itch. We now have the nerve map for itching, as we do for other sensations. But a deeper puzzle remains: how much of our sensations and experiences do nerves really explain? In the operating room, a neurosurgeon washed out and debrided M. Later, a plastic surgeon covered it with a graft of skin from her thigh. Though her head was wrapped in layers of gauze and she did all she could to resist the still furious itchiness, she awoke one morning to find that she had rubbed the graft away. The doctors returned her to the operating room for a second skin graft, and this time they wrapped her hands as well. She rubbed it away again anyway. A psychiatric team was sent in to see her each day, and the resident would ask her, ? Did you do anything repetitive? Did you have to count everything you saw? He tracked down her family and asked them, but they said no, too. Psychology tests likewise ruled out obsessive- compulsive disorder. They showed depression, though, and, of course, there was the history of addiction. So the doctors still thought her scratching was from a psychiatric disorder. They gave her drugs that made her feel logy and sleep a lot. But the itching was as bad as ever, and she still woke up scratching at that terrible wound.
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