Mice with a condition that serves as a laboratory model for Down syndrome perform better on memory and learning tasks as adults if they were treated before birth with neuroprotective peptides, according to researchers at the National Institutes of Health. Down syndrome results when an individual receives an extra copy of chromosome 21. According to the Centers for Disease Control and Prevention, Down syndrome occurs in 1 of every 691 births. Features of Down syndrome include delays in mental and physical development and poor muscle tone. These features may vary greatly, ranging from mild to severe. The researchers studied growth factors that are important at certain key stages of brain development in the womb. Named for the first three amino acids making up their chemical sequence, NAP and SAL, are small peptides (small protein sub units) of two proteins. These two proteins enhance the ability of brain cells to receive and transmit signals, and enable them to survive. (NAP is an abbreviation for NAPVSIPQ and SALfor SALLRSIPA.) The mice in the study had an extra copy of mouse chromosome 16, which has mouse counterparts to 55 percent of the genes on human chromosome 21.The researchers treated pregnant mice with NAP and SAL for five days, then tested the mouse offspring at 8 to 12 months of age, comparing them to mice treated with a saline solution (placebo). Mice with the extra chromosomal material that were treated with NAP and SAL in the womb learned as well as mice that did not have the extra chromosome, and significantly faster than mice with the extra chromosome that were treated with saline solution.

Keyword: Development of the Brain; Genes & Behavior
Link ID: 17555 - Posted: 12.01.2012

by Jessica Hamzelou A single session of nerve stimulation has improved the movement of people with spinal cord injuries. Mimicking the passage of nerve signals by stimulating a muscle as well as the brain has boosted recovery and helped people to regain better control of their movements. Voluntary movement requires a signal from the brain, which is passed down the spinal cord and then to neurons in muscles. Damage to the spinal cord can interrupt this pathway, resulting in paralysis. To improve the control of movement in people with these injuries, Monica Perez and Karen Bunday at the University of Pittsburgh in Pennsylvania used electrical and magnetic stimulation to strengthen the connection between two nerves involved in voluntary movement of the index finger. The pair used transcranial magnetic stimulation (TMS), a non-invasive technique in which a magnetic field alters brain activity, to target the corticospinal tract. This bundle of nerves connects movement-associated parts of the brain with the spinal cord. "The corticospinal tract plays a major role in the recovery of motor function in spinal cord injury," says Perez. Just 1 to 2 milliseconds after stimulating the brain, they used an electrode to stimulate a nerve that innervates an index-finger muscle – mimicking normal brain-to-muscle nerve signalling. © Copyright Reed Business Information Ltd.

Keyword: Regeneration
Link ID: 17554 - Posted: 12.01.2012

By Melissa Hogenboom BBC News Researchers say a baby's chance of being obese in childhood can be predicted at birth using a simple formula. The formula combines several known factors to estimate the risk of obesity. The authors of the study, published in PLos One, hope it will be used to identify babies at risk. Childhood obesity can lead to many health problems, including Type 2 diabetes and heart disease. Researchers from Imperial College London looked at 4,032 Finnish children born in 1986 and at data from two further studies of 1,503 Italian children and 1,032 US children. They found that looking at a few simple measurements, such as a child's birthweight and whether the mother smoked, was enough to predict obesity. Previously it had been thought that genetic factors would give bigger clues to later weight problems, but only about one in 10 cases of obesity is the result of a rare gene mutation that affects appetite. Obesity in children is rising, with the NHS estimating that 17% of boys and 15% of girls in England are now obese. BBC © 2012

Keyword: Obesity; Development of the Brain
Link ID: 17553 - Posted: 11.29.2012

By ANAHAD O'CONNOR Weight loss surgery, which in recent years has been seen as an increasingly attractive option for treating Type 2 diabetes, may not be as effective against the disease as it was initially thought to be, according to a new report. The study found that many obese Type 2 diabetics who undergo gastric bypass surgery do not experience a remission of their disease, and of those that do, about a third redevelop diabetes within five years of their operation. The findings contrast with the growing perception that surgery is essentially a cure for Type II diabetes. Earlier this year, two widely publicized studies reported that surgery worked better than drugs, diet and exercise in causing a remission of Type 2 diabetes in overweight people whose blood sugar was out of control, leading some experts to call for greater use of surgery in treating the disease. But the studies were small and relatively short, lasting under two years. The latest study, published in the journal Obesity Surgery, tracked thousands of diabetics who had gastric bypass surgery for more than a decade. It found that many people whose diabetes at first went away were likely to have it return. While weight regain is a common problem among those who undergo bariatric surgery, regaining lost weight did not appear to be the cause of diabetes relapse. Instead, the study found that people whose diabetes was most severe or in its later stages when they had surgery were more likely to have a relapse, regardless of whether they regained weight. Copyright 2012 The New York Times Company

Keyword: Obesity
Link ID: 17552 - Posted: 11.29.2012

Scicurious Guest Writer, Nicole Baganz! 4:02 PM. It took every ounce of energy I had to drag myself to the bathroom. Arriving in the room that is located 2 feet from my bed felt like a victory. I rifled through the medicine cabinet, stuck the thermometer in my mouth and collapsed on the bathroom floor. 103.2° F. Yep, I’m sick. Sleepiness. Fatigue. Loss of appetite and motivation. Lethargy. Leave me alone. We all know what it feels like to be sick. Clinicians collectively describe this group of symptoms as “sickness behavior”. Evolutionarily speaking, the idea that the immune system would produce these symptoms makes sense. An organism infected with a pathogenic bug should retreat from its social group to protect others from the spread of infection. The organism essentially shuts down in order to send every ounce of energy to the immune system to battle the bug that has invaded the body’s cells. This sickness state would facilitate recovery of the organism and also protect the community from the spread of the infection by limiting the interaction of the infected party from its entire social group. All of the symptoms of sickness behavior are displayed not only by people who have an infection, but also by those who have been diagnosed with Major Depressive Disorder (MDD). Could sickness behavior and MDD be linked? What happens in the brain to produce sickness behaviors, and how might these relate to depression? Mice are good models for scientists to use to study the effect of immune system activation on brain function and behavior (research studies that subject people to infectious agents before probing their brains in the name of science draw few willing volunteers). Laboratory mice also display sickness behavior when their immune systems are turned on. Sick rodents sleep more, eat less, and lose interest in drinking sugary water (usually a scrumptious treat for mice). They also stop interacting socially – mice are, by nature, very social creatures that like to sniff, groom, lick and cuddle up to their roommates. © 2012 Scientific American

Keyword: Depression
Link ID: 17551 - Posted: 11.29.2012

By David Levine People with depression or other mental illnesses often report trouble sleeping, daytime drowsiness and other sleep-related issues. Now a growing body of research is showing that treating sleep problems can dramatically improve psychiatric symptoms in many patients. Much of the latest work illustrates how sleep apnea, a common chronic condition in which a person repeatedly stops breathing during sleep, may cause or aggravate psychiatric symptoms. In past years sleep apnea has been linked to depression in small studies and limited populations. Now a study by the Centers for Disease Control and Prevention strengthens that connection. The CDC analyzed the medical records of nearly 10,000 American adults with sleep apnea. Men diagnosed with this disorder had twice the risk of depression—and women five times the risk—compared with those without sleep apnea. Writing in the April issue of Sleep, lead author Anne G. Wheaton and her colleagues speculate that in addition to interrupting sleep, the oxygen deprivation induced by sleep apnea could harm cells and disrupt normal brain functioning. Treating this disorder shows promise for reducing symptoms of depression, a recent study at the Cleveland Clinic suggests. In the experiment, patients went to bed wearing a mask hooked up to a machine that increases air pressure in their throat. The increased pressure prevents the airway from collapsing, which is what causes breathing to cease in most cases of this disorder. Using this machine, psychiatrist Charles Bae and his colleagues treated 779 patients who had been diagnosed with sleep apnea. After an average of 90 days of sleeping with the machine, all the patients scored lower on a common depression survey than before the treatment—regardless of whether they had a prior diagnosis of depression or were taking an antidepressant. The data were presented in June at the SLEEP 2012 conference in Boston. © 2012 Scientific American

Keyword: Sleep; Depression
Link ID: 17550 - Posted: 11.28.2012

High-resolution real-time images show in mice how nerves may be damaged during the earliest stages of multiple sclerosis. The results suggest that the critical step happens when fibrinogen, a blood-clotting protein, leaks into the central nervous system and activates immune cells called microglia. "We have shown that fibrinogen is the trigger," said Katerina Akassoglou, Ph.D., an associate investigator at the Gladstone Institute for Neurological Disease and professor of neurology at the University of California, San Francisco, and senior author of the paper published online in Nature Communications. Multiple sclerosis, or MS, is thought to be an autoimmune disease in which cells that normally protect the body against infections attack nerve cells in the brain and spinal cord, often leading to problems with vision, muscle strength, balance and coordination, thinking and memory. Typically during MS, the immune cells destroy myelin, a protective sheath surrounding nerves, and eventually leading to nerve damage. The immune attack also causes leaks in the blood-brain barrier, which normally separates the brain from potentially harmful substances in the blood. "Dr. Akassoglou has focused on the role of the blood-brain barrier leak in MS and has discovered that leakage of the blood clotting protein fibrinogen can trigger brain inflammation," said Ursula Utz, Ph.D., M.B.A., a program director at NIH's National Institute of Neurological Disorders and Stroke (NINDS). Microglia are cells traditionally thought to control immunity in the nervous system. Previous studies suggested that leakage of fibrinogen activates microglia.

Keyword: Multiple Sclerosis; Glia
Link ID: 17549 - Posted: 11.28.2012

By GRETCHEN REYNOLDS Recently, researchers in England set out to determine whether weekend golfers could improve their game through one of two approaches. Some were coached on individual swing technique, while others were instructed to gaze fixedly at the ball before putting. The researchers hoped to learn not only whether looking at the ball affects performance, but also whether where we look changes how we think and feel while in action. Back in elementary school gym class, virtually all of us were taught to keep our eyes on the ball during sports. But a growing body of research suggests that, as adults, most of us have forgotten how to do this. When scientists in recent years have attached sophisticated, miniature gaze-tracking devices to the heads of golfers, soccer players, basketball free throw shooters, tennis players and even competitive sharpshooters, they have found that a majority are not actually looking where they believe they are looking or for as long as they think. It has been less clear, though, whether a slightly wandering gaze really matters that much to those of us who are decidedly recreational athletes. Which is in part why the British researchers had half of their group of 40 duffers practice putting technique, while the other half received instruction in a gaze-focusing technique known as “Quiet Eye” training. Quiet Eye training, as the name suggests, is an attempt to get people to stop flicking their focus around so much. But “Quiet Eye training is not just about looking at the ball,” says Mark Wilson, who led the study, published in Psychophysiology, and is a senior lecturer in human movement science at the University of Exeter in England. “It is about looking at the ball for long enough to process aiming information.” It involves reminding players to first briefly sight toward the exact spot where they wish to send the ball, and then settle their eyes onto the ball and hold them there. Copyright 2012 The New York Times Company

Keyword: Vision
Link ID: 17548 - Posted: 11.28.2012

By Christina Agapakis White is a mixture, made by a combination of signals at equal intensity across a perceptual space. White light can be split up into all the colors of the visible spectrum, and white noise covers a range of frequencies within the audible range. Our other senses don’t have as clearly defined ranges of perception. We can’t give a smell, a taste, or a texture a number the same way that a color or a tone can be defined by a wavelength, but a fascinating recent paper shows that by mixing many different smelly molecules at equal intensities, our perception of the odor will converge on “olfactory white.” The researchers created this strangely neutral smell from different mixtures of up to thirty odors, chosen from a set of 86 molecules that represent a wide range of the kinds of things that we can smell. Human “olfactory stimulus space” contains thousands of molecules, from the fragrant and floral to the putrid. We can distinguish and name many smells, but odors don’t map neatly onto a one dimensional spectrum. Sampling the multidimensional stimulus space of odors requires a much more complicated mapping of the smell universe. The figure on the left shows the position of the 86 molecules within two maps of olfactory stimulus space. The first is based on the way that we perceive odors (perceptual space, A) and the second based on the chemical structures of the molecules (physicochemical space, B). The perceptual map is built with data from Dravnieks’ Atlas of Odor Character Profiles of 144 different molecules. Each smell was compared by 150 professional noses against a list of 146 different odor descriptions like “fruity” “etherish” “decayed” or “seasoning for meat.” © 2012 Scientific American,

Keyword: Chemical Senses (Smell & Taste)
Link ID: 17547 - Posted: 11.28.2012

By Tanya Lewis A coma patient’s chances of surviving and waking up could be predicted by changes in the brain’s ability to discriminate sounds, new research suggests. Recovery from coma has been linked to auditory function before, but it wasn’t clear whether function depended on the time of assessment. Whereas previous studies tested patients several days or weeks after comas set in, a new study looks at the critical phase during the first 48 hours. At early stages, comatose brains can still distinguish between different sound patterns,. How this ability progresses over time can predict whether a coma patient will survive and ultimately awaken, researchers report. “It’s a very promising tool for prognosis,” says neurologist Mélanie Boly of the Belgian National Fund for Scientific Research, who was not involved with the study. “For the family, it’s very important to know if someone will recover or not.” A team led by neuroscientist Marzia De Lucia of the University of Lausanne in Switzerland studied 30 coma patients who had experienced heart attacks that deprived their brains of oxygen. All the patients underwent therapeutic hypothermia, a standard treatment to minimize brain damage, in which their bodies were cooled to 33° Celsius for 24 hours. De Lucia and colleagues played sounds for the patients and recorded their brain activity using scalp electrodes — once in hypothermic conditions during the first 24 hours of coma, and again a day later at normal body temperature. The sounds were a series of pure tones interspersed with sounds of different pitch, duration or location. The brain signals revealed how well patients could discriminate the sounds, compared with five healthy subjects. © Society for Science & the Public 2000 - 2012

Keyword: Consciousness; Brain imaging
Link ID: 17546 - Posted: 11.27.2012

By James Gallagher Health and science reporter, BBC News The possibility that autism is linked to traffic pollution has been raised by researchers in California. Their study of more than 500 children said those exposed to high levels of pollution were three times more likely to have autism than children who grew up with cleaner air. However, other researchers said traffic was a "very unlikely" and unconvincing explanation for autism. The findings were presented in the Archives of General Psychiatry journal. Data from the US Environmental Protection Agency were used to work out levels of pollution for addresses in California. This was used to compare exposure to pollution, in the womb and during the first year of life, in 279 children with autism and 245 without. The researchers from the University of Southern California said children in homes exposed to the most pollution "were three times as likely to have autism compared with children residing in homes with the lowest levels of exposure". BBC © 2012

Keyword: Autism; Neurotoxins
Link ID: 17545 - Posted: 11.27.2012

By JAMES GORMAN For the first time, researchers at the Massachusetts Institute of Technology report, brain imaging has been able to show in living patients the progressive damage Parkinson’s disease causes to two small structures deep in the brain. The new technique confirms some ideas about the overall progress of the disease in the brain. But the effects of Parkinson’s vary in patients, the researchers said, and in the future, the refinement in imaging may help doctors monitor how the disease is affecting different people and adjust treatment accordingly. The outward symptoms and progress of Parkinson’s disease — tremors, stiffness, weakness — have been well known since James Parkinson first described them in 1817. But its progress in the brain has been harder to document. Some of the structures affected by the disease have been buried too deep to see clearly even with advances in brain imaging. An important recent hypothesis about how the disease progresses was based on the examinations of brains of patients who had died. Now, a group of scientists at M.I.T. and Massachusetts General Hospital report that they have worked out a way to combine four different sorts of M.R.I. to get clear pictures of damage to two brain structures in people living with Parkinson’s. In doing so, they have added support to one part of the recent hypothesis, which is that the disease first strikes an area involved in movement and later progresses to a higher part of the brain more involved in memory and attention. Suzanne Corkin, a professor emerita of behavioral neuroscience at M.I.T. and the senior author on the paper published online Monday in The Archives of Neurology, said that this progression was part of the hypothesis put forward in 2003 by Heiko Braak, a German neuroscientist, based on autopsies. © 2012 The New York Times Company

Keyword: Parkinsons
Link ID: 17544 - Posted: 11.27.2012

By Maggie Fox, NBC News Seniors who fit in the most daily physical activity – from raking leaves to dancing – can have more gray matter in important brain regions, researchers reported on Monday. The scientists have images that show people who were the most active had 5 percent more gray matter than people who were the least active. Having more little gray brain cells translates into a lower risk of Alzheimer’s disease, other studies have shown. “People really want to know what they can do to reduce their risk of Alzheimer’s disease,” said Dr. Cyrus Raji of the University of California in Los Angeles, who presented his team’s findings to a meeting of the Radiological Society of North America. Raji’s team looked at the records of 876 adults, who were recruited into a larger study on heart health starting in 1989. They all got magnetic resonance imaging (MRI) brain scans in 1998 and 1999, when they were on average 78 years old, and filled out detailed questionnaires on exercise and other types of activity. Most of them were a little overweight – with a body mass index or BMI of 27. People with BMIs above 25 are considered overweight and at 30 they are considered clinically obese. The researchers found a huge difference in the amount of activity people reported. They were asked about everything from cycling to yard work, dancing and bicycle riding. © 2012 NBCNews.com

Keyword: Alzheimers
Link ID: 17543 - Posted: 11.27.2012

By BENEDICT CAREY For years they have lived as orphans and outliers, a colony of misfit characters on their own island: the bizarre one and the needy one, the untrusting and the crooked, the grandiose and the cowardly. Their customs and rituals are as captivating as any tribe’s, and at least as mystifying. Every mental anthropologist who has visited their world seems to walk away with a different story, a new model to explain those strange behaviors. This weekend the Board of Trustees of the American Psychiatric Association will vote on whether to adopt a new diagnostic system for some of the most serious, and striking, syndromes in medicine: personality disorders. Personality disorders occupy a troublesome niche in psychiatry. The 10 recognized syndromes are fairly well represented on the self-help shelves of bookstores and include such well-known types as narcissistic personality disorder, avoidant personality disorder, as well as dependent and histrionic personalities. But when full-blown, the disorders are difficult to characterize and treat, and doctors seldom do careful evaluations, missing or downplaying behavior patterns that underlie problems like depression and anxiety in millions of people. The new proposal — part of the psychiatric association’s effort of many years to update its influential diagnostic manual — is intended to clarify these diagnoses and better integrate them into clinical practice, to extend and improve treatment. But the effort has run into so much opposition that it will probably be relegated to the back of the manual, if it’s allowed in at all. © 2012 The New York Times Company

Keyword: Emotions
Link ID: 17542 - Posted: 11.27.2012

The long-held view that a full moon or even a new moon triggers psychological problems has been debunked by a study from Montreal. Researchers at the University of Laval's School of Psychology evaluated patients visiting Montreal's Sacré-Coeur Hospital and Hôtel-Dieu de Lévis between March 2005 and April 2008 and found no correlation between anxiety disorders and the phases of the moon — despite, it seems, what 80 per cent of nurses and 64 per cent of doctors surveyed believe. These researchers analyzed 771 individuals who had shown up at the emergency room with chest pains for which no medical cause could be determined. Psychological evaluations indicated many were suffering anxiety, panic attacks, mood disorders or suicidal thoughts. The time of their visit was then correlated with the phase of the moon at that moment. "We observed no full-moon or new-moon effect on psychological problems," said lead researcher Genevieve Belleville whose study is published in General Hospital Psychiatry. The study went on to suggest that health professionals may think there are more mental problems during a full-moon phase due to "self-fulfilling prophecies." © CBC 2012

Keyword: Biological Rhythms; Depression
Link ID: 17541 - Posted: 11.27.2012

Philip Ball Learning to read Chinese might seem daunting to Westerners used to an alphabetic script, but brain scans of French and Chinese native speakers show that people harness the same brain centres for reading across cultures. The findings are published today in the Proceedings of the National Academy of Sciences1. Reading involves two neural systems: one that recognizes the shape of the word and a second that asseses the physical movements used to make the marks on a page, says study leader Stanislas Dehaene, a cognitive neuroscientist the National Institute of Health and Medical Research in Gif-sur-Yvette, France. But it has been unclear whether the brain networks responsible for reading are universal or culturally distinct. Previous studies have suggested that alphabetic writing systems (such as French) and logographic ones (such as Chinese, in which single characters represent entire words) writing systems might engage different networks in the brain. To explore this question, Dehaene and his colleagues used functional magnetic resonance imaging to examine brain activity in Chinese and French people while they read their native languages. The researchers found that both Chinese and French people use the visual and gestural systems while reading their native language, but with different emphases that reflect the different demands of each language. © 2012 Nature Publishing Group

Keyword: Language
Link ID: 17540 - Posted: 11.27.2012

By Scicurious Animals don’t handle stress well. I’m not talking about acute stressors, the predator charging at you through the brush, you run away and it’s over. We handle that stress very well indeed. But severe stress, losing a job, a divorce, a death in the family, these can really wear us down. Severe life stressors can not only impact your physical health, they also often occur before the onset of mental illness, particularly major depressive disorder. Depression takes many forms (lack of interest in activities, sleep changes, eating changes, severely depressed mood), but one of the most debilitating ones is the way that it impacts motivation. While some stressors (like, say, a deadline), might before have been a motivator, making you work to get it done, during depression, these stressors become insurmountable obstacles. Things you did before you couldn’t possibly get done now. You’ll never make the deadline. You can’t run the race. Stress can’t motivate you any more. What has changed? To look at this, Lemos et al at the University of Washington, Seattle, looked at one of the signals in response to stress in the brain: corticotropin releasing factor (CRF). CRF is the first step in the process that eventually allows cortisol to be released into the bloodstream, the molecule we usually associate with stress. You can see at the top of the chain there CRF being released from the hypothalamus. From there the next step in the chain is the anterior pituitary, and from there adrenocorticotropic releasing hormone (ACTH) is released, and stimulates the adrenal glands (sitting in little pads of fat above your kidneys) to release cortisol. But in the brain, it’s more complicated than that. CRF isn’t just released from the hypothalamus to the pituitary, it’s released to other regions, too. © 2012 Scientific American

Keyword: Stress
Link ID: 17539 - Posted: 11.27.2012

David Perlman With an ultimate goal to help paralyzed patients achieve a degree of independence, Stanford brain researchers report they have taken a promising step forward in efforts to link nerve centers in the human brain with computers controlled by only a person's thought. In their latest development, the Stanford scientists have successfully enabled a pair of rhesus monkeys to move a virtual cursor across a computer screen merely by thinking about their response to human commands. The monkeys' ability to manipulate a cursor without using a mouse is based on a powerful new algorithm, a mathematical computing program devised by Vikash Gilja, a Stanford electrical engineer and computer scientist. Four years ago, neurosurgeons at Brown University and Massachusetts General Hospital had demonstrated a simpler version of an algorithm that enabled completely paralyzed humans with implanted sensors in their brains to command a cursor to move erratically toward targets on a computer screen. But with Gilja's algorithm, called ReFit, the monkeys showed they could aim their virtual cursor, a moving dot of light, at another bright light on a computer screen, and hold it steadily there for 15 seconds - far more precisely than the humans four years ago. With the new algorithm, they were able to perform their thinking tasks faster and more accurately as they sat comfortably in a chair facing the computer. The development is "a big step toward clinically useful brain-machine technology that has faster, smoother, and more natural movements" than anything before it, said James Gnadt of the National Institute of Neurological Disorders and Stroke. © 2012 Hearst Communications Inc.

Keyword: Robotics
Link ID: 17537 - Posted: 11.26.2012

Alla Katsnelson Human eyes, set as they are in front-facing sockets, give us a limited angle of view: we see what is directly in front of us, with only a few degrees of peripheral vision. But bats can broaden and narrow their 'visual field' by modulating the frequency of the squeaks they use to navigate and find prey, researchers in Denmark suggest today in Nature1. Bats find their way through the night by emitting sonar signals and using the echoes that return to them to create a map of their surroundings — a process called echolocation. Researchers have long known that small bats emit higher-frequency squeaks than larger bats, and most assumed that the difference arises because the smaller animals must catch smaller insects, from which low-frequency sound waves with long wavelengths do not reflect well. That didn't sound right to Annemarie Surlykke, a neurobiologist who studies bat echolocation at the University of Southern Denmark in Odense. “When you look at the actual frequencies, small bats would be able to detect even the smallest prey they take with a much lower frequency,” she says. “So there must be another reason.” Surlykke and her colleagues decided to test the hypothesis by studying six related species of bat that varied in size. They captured the animals in the wild and set them loose in a flight room — a pitch-dark netted corridor 2.5 metres high, 4.8 metres wide and 7 metres long, rigged on all sides with microphones and infrared cameras. “It’s a pretty confined space, so this corresponds to flying close to vegetation,” says Surlykke. © 2012 Nature Publishing Group

Keyword: Hearing
Link ID: 17536 - Posted: 11.26.2012

Published by drrubidium Out-of-control libido or drug habit? Take Nervine. Nervous, excitable, wakeful, or restless? Take Nervine. Over-the-counter Nervine wasn't a wonder drug, just a cocktail of the oldest class of sedatives - inorganic bromides. Nervine contained the most commonly used bromides - sodium bromide (NaBr), potassium bromide (KBr), and ammonium bromide (NH4Br). These particular bromides were once so popular that only aspirin sold better. The use of bromides to treat "nerves" was so prevalent that 'bromide' entered the lexicon of common speech. Instead of "calm down", people were instructed to "take a bromide". Instead of calling someone a 'bore', the term 'bromide' was a used to denote "a commonplace or tiresome person". Bromides may owe their sedative effect to a family connection. The element bromine is in the same chemical family as the element chlorine – the halogens. Being a chemical family, chlorine and bromine have similar properties. Both form single, negatively charged ions (monovalent anions) via oxidation-reduction reactions - chloride (Cl-) and bromide (Br-). Chloride is found in nearly all of our cells, having its own set cell membrane-crossing highways (chlorine channel). The regulated flow of chloride (as hydrated chloride) across neuron membranes is key to communication between neurons. Being family and all, bromide (as hydrated bromide) can travel along chloride's highways. But hydrated bromide is a teeny bit smaller than hydrated chloride, allowing hydrated bromide to get into cells faster than hydrated chloride. A flood of anions, such as bromide or chloride, into a neuron makes it more negative than it would be at rest, a state called 'hyperpolarization'. It's hard for other neutrons to stimulate - talk to - hyperpolarized neurons. Less neuron stimulation can translate to a feeling of calm. Thirty-Seven Copyright © 2012

Keyword: Drug Abuse
Link ID: 17535 - Posted: 11.26.2012