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Posted by Dr. Sushrut Jangi The child's family and physician were making decisions about how to treat this disease. Many readers voted that starting an ADHD medication and behavioral therapy together might be a good way forward. Her doctor agrees with this approach. "A lot of judgement happens the day I talk about starting medicines for young children," Dr. Chan says. Most parents have already tried numerous other routes, such as behavioral therapy which is frequently recommended first. But behavioral therapy alone is hard to implement. "It's hard to access and there's not too many families who can actually carry it out," Chan says. "If you're a single parent working multiple jobs, its really hard to fit the time to take your child regularly. It's a huge time investment." J's parents tried the behavioral therapy route and they worked hard at it. But he wasn't improving. Dr. Chan is more than familiar with the culture of fear that surrounds ADHD medications, but she feels these fears are overinflated. Consequently, children who might benefit from being on medicine get delayed treatments, which can have harmful social effects. "Children in his class already know that he's different, so they react to him differently. Children with ADHD start getting negative feedback from their peers early on." Dr. Chan feels that this is one potential justification for starting medications early. "These medicines can help children get out of cycles of negative-feedback. And we're not condemning children to medicine for the rest of their lives. They can be started as a trial, and then stopped down the line." © 2013 NY Times Co.

Keyword: ADHD; Drug Abuse
Link ID: 18551 - Posted: 08.24.2013

By Jessica Shugart Sometimes it pays to be mediocre. A new study shows that sheep with a 50/50 blend of genes for small and big horns pass along more of their genes over a lifetime than their purely big-horned brethren, who mate more often. The finding offers rare insight into an enduring evolutionary paradox—why some traits persist despite creating a reproductive disadvantage. The results, published online August 21 in Nature, reveal that while big-horned sheep mated most successfully each season, small-horned sheep survived longer. Rams who inherited one of each type of gene from their parents got the best of both worlds: they lived longer than bigger-horned sheep and mated more successfully than those with the smallest horns. As a result, middle-of-the-road sheep passed on more of their genes over time. “They’re the fittest of them all,” says Jon Slate of the University of Sheffield in Scotland, who led the study. “This is a marvelous combination of using the most modern tools available to confirm classic older views of sexual selection,” says evolutionary geneticist Allen Moore of the University of Georgia in Athens, who was not involved in the study. Traits such as bold peacock feathers and giant antlers evolved to garner the attention of prospective females and boost reproductive success. Yet if each generation of females continues to pick the most stellar males, Charles Darwin wondered, how do sub-par versions of a trait continue to persist? “It’s something that has preoccupied evolutionary biologists ever since,” Slate says. © Society for Science & the Public 2000 - 2013

Keyword: Evolution; Sexual Behavior
Link ID: 18550 - Posted: 08.22.2013

By Patrick Cooney The Disney film Finding Nemo lied to your kids! The people at Disney would simply argue that they altered reality to create a more entertaining storyline, but read below for the true story, and you tell me which you think is more entertaining. How Finding Nemo started: Father and mother clownfish are tending to their clutch of eggs at their sea anemone when the mother is eaten by a barracuda. Nemo is the only surviving egg, and he grows up in his father’s anemone before getting lost on a crazy adventure! How Finding Nemo should have started if it were biologically accurate: Father and mother clownfish are tending to their clutch of eggs at their sea anemone when the mother is eaten by a barracuda. Nemo hatches as an undifferentiated hermaphrodite (as all clownfish are born) while his father transforms into a female clownfish now that his female mate is dead. Since Nemo is the only other clownfish around, he becomes male and mates with his father (who is now female). Should his father die, Nemo would change into a female clownfish and mate with another male. Although a much different storyline, it still sounds like a crazy adventure! As you can see, the first minute of Finding Nemo, outside of the talking fish part, is the only biologically accurate part of the movie. Considering that Disney demonstrated reproduction and the killing of the mother in the first minute of the movie, how did it decide that a natural sex change is outside the bubble of viewable material? © 2013 The Slate Group, LLC

Keyword: Sexual Behavior
Link ID: 18549 - Posted: 08.22.2013

By JULIE TURKEWITZ Samantha Dittmeier was the youngest of Karen Allar’s four children. “She was very loving, very compassionate,” said Ms. Allar, 51, an employment counselor who lives on Long Island. “Unfortunately, the addiction got to her.” Ms. Dittmeier, 23, died of a heroin overdose in January, leaving behind her 3-year-old son, Aiden. Ms. Allar is haunted, she said, not just by her daughter’s tumble into addiction, but also by the circumstances of her death. She wonders if her life might have been saved if the emergency workers who treated her had been armed with naloxone, a powerful drug that can reverse the effects of an overdose. “You start to get that sick feeling again,” Ms. Allar said, recounting a frantic race to the hospital just before Ms. Dittmeier’s death. “I’m back at work. I’m trying to think positive about such a horrible situation.” On Long Island and across New York State, drug overdoses are taking an increasing toll. The most common killers are opioids, a class of painkillers that includes prescription drugs like Vicodin, OxyContin and Percocet, as well as illegal narcotics like heroin. In Suffolk and Nassau Counties, the two that make up Long Island, 338 people died of opioid overdoses in 2012, up from 275 in 2008, according to county records. Statewide, opioid overdoses killed 2,051 people in 2011, more than twice the number that they killed in 2004. The spate of deaths is spurred, in part, by the easy access to prescription drugs. As a result, the state has begun several efforts to stem access to prescription drugs. A new law aims to stop addicts from gaining access to multiple rounds of medication by requiring doctors to consult an Internet database that tracks prescriptions. © 2013 The New York Times Company

Keyword: Drug Abuse
Link ID: 18548 - Posted: 08.22.2013

By Cristy Gelling Bacteria can directly trigger the nerves that sense pain, suggesting that the body’s own immune reaction is not always to blame for the extra tenderness of an infected wound. In fact, mice with staph-infected paws showed signs of pain even before immune cells had time to arrive at the site, researchers report online August 21 in Nature. “Most people think that when they get pain during infection it’s due to the immune system,” says coauthor Isaac Chiu of Boston Children’s Hospital and Harvard Medical School. Indeed, immune cells do release pain-causing molecules while fighting off invading microbes. But in recent years scientists have started uncovering evidence that bacteria can also cause pain. Chiu and his colleagues stumbled on this idea when they grew immune cells and pain-sensing cells together in a dish. The researchers were trying to activate the immune cells by adding bacteria to the mix but were surprised to see an immediate response in the nerve cells instead. This made them suspect that nerve cells were sensing the bacteria directly. To take a closer look at a real infection, the team injected the back paws of mice with Staphylococcus aureus, a bacterium that causes painful sores in humans. The researchers measured how tender the infected area was by poking it with flexible filaments of plastic. If the mouse didn’t like being prodded, it would lift its paw, giving a sensitive measure of each infection’s ouch factor. © Society for Science & the Public 2000 - 2013

Keyword: Pain & Touch; Neuroimmunology
Link ID: 18547 - Posted: 08.22.2013

By Caitlin Shure The newest chemical under investigation for managing Alzheimer’s disease (AD) is actually not new at all. Insulin, the therapeutic hormone all-too familiar to individuals with diabetes, has been around for decades. In fact December will mark 90 years since its discoverers earned the Nobel Prize in Physiology or Medicine for the extraction of insulin for clinical use. Yet to say that insulin has been under our noses all these years wouldn’t exactly be correct. Because if it had been under our noses, we might have sensed its neurologic benefits sooner. The latest insulin therapy is not delivered via injection like its diabetes-treating counterparts, nor does it come in the form of a pill or a patch like the cholinesterase inhibitors often prescribed to patients with AD. Instead this novel therapeutic enters the body through the nose—the only entry point that gives insulin a chance of reaching the brain. A large peptide molecule, insulin from the blood cannot float easily into the brain because the blood brain barrier (BBB), a sort of neuroprotective moat, prevents its transport. Fortified by cellular guards called tight junctions, the BBB rejects many pharmacologic hopefuls, allowing entrance only to certain types of substances. Namely small or lipophilic molecules can be administered orally (or via injection, or through the skin) and as long as the relevant chemicals end up in the blood stream, they can casually saunter across the BBB and act on the brain. Large and cumbersome, insulin does not have this luxury and must therefore take a more creative route across the moat. © 2013 Scientific American

Keyword: Alzheimers; Hormones & Behavior
Link ID: 18546 - Posted: 08.22.2013

By Geoffrey Mohan If you can’t quite get that nine-note treble opening to "Fur Elise," just sleep on it. The brain will rehearse, reorganize and nail the sequential motor tasks that help you play piano or type on a keyboard. How that consolidation of memory happens has remained largely a mystery, despite telling evidence that the brain’s motor cortex appears to be quite busy during sleep. Now, a team led by Brown University neuroscientists believes it has found the source of the sleeping piano lesson, and it’s not where many expected it to be. Neuroscience has been fixated since its founding on why the brain “needs” that peculiar mix of dormancy and random activity known as sleep. And it equally wondered why we emerge from it better able to do things. Slowly, evidence accrued that we were “learning” during sleep -- consolidating memory in ways that would make waking tasks more successful. It seemed deepest sleep, not the familiar rapid-eye-movement type, had the most effect on our brain’s abilty to reorganize and prepare to perform better in waking hours. “It has been very difficult to measure brain activation during sleep,” said Brown University neuroscientist Masako Tamaki, lead author of the study published online Tuesday in the Journal of Neuroscience. “So it was unclear what brain region was involved.”

Keyword: Sleep; Learning & Memory
Link ID: 18545 - Posted: 08.22.2013

By Dina Fine Maron Using sensors tucked inside the ears of live gerbils, researchers from Columbia University are providing critical insights into how the ear processes sound. In particular, the researchers have uncovered new evidence on how the cochlea, a coiled portion of the inner ear, processes and amplifies sound. The findings could lay the initial building blocks for better hearing aids and implants. The research could also help settle a long-simmering debate: Do the inner workings of the ear function somewhat passively with sound waves traveling into the cochlea, bouncing along sensory tissue, and slowing as they encounter resistance until they are boosted and processed into sound? Or does the cochlea actively amplify sound waves? The study, published in Biophysical Journal, suggests the latter is the case. The team, led by Elizabeth Olson, a biomedical engineer of Columbia University, used sensors that simultaneously measured small pressure fluctuations and cell-generated voltages within the ear. The sensors allowed the researchers to pick up phase shifts—a change in the alignment of the vibrations of the sound waves within the ear—suggesting that some part of the ear was amplifying sound. What causes that phase shift is still unclear although the researchers think the power behind the phase shift comes from the outer hair cells. Apparently the hair cells’ movement serves to localize and sharpen the frequency region of amplification. The researchers wrote that the mechanism appears to be akin to a child swinging on the playground. If somebody pushes a swing just once, the oscillations will eventually die out. If a child pumps her legs at certain times, however, it will put energy into the oscillations—that is power amplification at work. © 2013 Scientific American

Keyword: Hearing
Link ID: 18544 - Posted: 08.22.2013

By Neuroskeptic An intriguing new paper in the Journal of Neuroscience introduces a new optical illusion – and, potentially, a new way to see ones own brain activity. The article is called The Flickering Wheel Illusion: When α Rhythms Make a Static Wheel Flicker by Sokoliuk and VanRullen. Here’s the illusion: It’s a simple black and white “wheel” with 32 spokes. To see the illusion, get the wheel in your peripheral vision. Look around the edge of your screen and maybe a bit beyond – you should find a ‘sweet spot’ at which the center of the wheel starts to ‘flicker’ on and off like a strobe light. Remarkably, it even works as an afterimage. Find a ‘sweet spot’, stare at that spot for a minute, then look at a blank white wall. You should briefly see a (color-reversed) image of the wheel and it flickers like the real one (I can confirm it works for me). By itself, this is just a cool illusion. There are lots of those around. What makes it neuroscientifically interesting is that – according to Sokoliuk and VanRullen – that flickering reflects brain alpha waves. First some background. Alpha (α) waves are rhythmical electrical fields generated in the brain. They cycle with a frequency of about 10 Hz (ten times per second) and are strongest when you have your eyes closed, but are still present whenever you’re awake. When Hans Berger invented the electroencephalograph (EEG) and hooked it up to the first subjects in 1924, these waves were the first thing he noticed – hence, “alpha”. They’re noticable because they’re both strong and consistent. They’re buzzing through your brain right now. But this raises a mystery – why don’t we see them? Alpha waves are generated by rhythmical changes in neuronal activity, mainly centered on the occipital cortex. Occipital activity is what makes us see things. So why don’t we see something roughly 10 times every second?

Keyword: Vision
Link ID: 18543 - Posted: 08.22.2013

Moheb Costandi Exposure to nicotine in the womb increases the production of brain cells that stimulate appetite, leading to overconsumption of nicotine, alcohol and fatty foods in later life, according to a new study in rats. Smoking during pregnancy is known to alter fetal brain development and increase the risk of premature birth, low birth weight and miscarriage. Prenatal exposure to nicotine also increases the likelihood of tobacco use and nicotine addiction in later life, but exactly how is unclear. To understand the mechanisms behind this effect, Sarah Leibowitz, a behavioural neurobiologist at the Rockefeller University in New York, and her colleagues injected pregnant rats with small doses of nicotine — which the researchers say are comparable to the amount a pregnant woman would get from smoking one cigarette a day — and then examined the brains and behaviour of the offspring. In a paper published today in Journal of Neuroscience1, they found that nicotine increased the production of specific types of neurons in the amygdala and hypothalamus. These cells produce orexin, enkephalin and melanin-concentrating hormone, neuropeptides that stimulate appetite and increase food intake. Rats exposed to nicotine in the womb had more of these cells and produced more of the neuropeptides than those that were not, and this had long-term consequences on their behaviour. As adolescents, they not only self-administered more nicotine, but also ate more fat-rich food and drank more alcohol. © 2013 Nature Publishing Group

Keyword: Drug Abuse; Development of the Brain
Link ID: 18542 - Posted: 08.21.2013

Linda Carroll TODAY contributor Whether it’s “One Flew Over the Cuckoo’s Nest,” “Girl Interrupted,” or “Homeland,” Hollywood’s portrayals of electroconvulsive therapy have never been pretty. And the images from those movies and TV shows have only added to a stigma that keeps many desperate patients from opting for a therapy that might turn their lives around, experts say. “We can’t get past the stigma of all the visuals we’ve seen from movies and the fact that it seems so antiquated when you consider modern medicine,” NBC chief medical editor Dr. Nancy Snyderman told TODAY’s Matt Lauer. “But time and time and time again if you look at patients who have severe depression who don’t respond to medications, they will tell you that ECT works.” That’s certainly true in Denise Stewart’s case. Stewart, a mother of two, suffers from schizoaffective disorder. Her hallucinations were pushing her closer and closer to suicide each day. “There would be voices in my head that would sit there and say, ‘Denise, see the knife in the kitchen? Cut your wrists. Denise, see those pills over there? Take all those pills,’” she told TODAY. After antidepressants made Stewart’s condition worse, her doctors suggested ECT. And the change was dramatic. “If it hadn’t been for the electroconvulsive therapy, I wouldn’t be alive right now,” Stewart said. These days an estimated 100,000 Americans undergo ECT each year – and the process is a lot different from what you see in the media, experts say.

Keyword: Depression; Learning & Memory
Link ID: 18541 - Posted: 08.21.2013

Philip Ball He is sometimes called the first rock star. He would whip his long hair around as he played, beads of sweat flying into the audience, and women would swoon or throw their clothes on to the stage. This is not Mick Jagger or Jimmy Page, but Franz Liszt, the nineteenth-century Hungarian pianist whose theatrical recitals made the composer Robert Schumann say that “a great deal of poetry would be lost” had Liszt played behind a screen. But who cares about the histrionics — it’s the music that matters, right? Not according to the latest study, which shows that people’s judgements about the quality of a musical performance are influenced more by what they see than by what they hear. The findings, reported this week in the Proceedings of the National Academy of Sciences by social psychologist Chia-Jung Tsay of University College London1, may be embarrassing and even shocking to music lovers. The vast majority of participants in Tsay’s experiments — around 83% of both untrained participants and professional musicians — insisted at the outset that sound was their key criterion for assessing video and audio recordings of performances. Yet it wasn’t. The participants were presented with recordings of the three finalists in each of ten prestigious international competitions, and were asked to guess the winner. With just sound, or sound and video, novices and experts both guessed right at about the same level as chance (33% of the time), or a little less. But with silent video alone, the success rate for both was about 46–53%. The experts did no better than the novices. © 2013 Nature Publishing Group

Keyword: Emotions; Hearing
Link ID: 18540 - Posted: 08.21.2013

By Ella Davies Reporter, BBC Nature An unusual caterpillar uses the sun to navigate as it jumps to safety, according to scientists. The larva of Calindoea trifascialis, a species of moth native to Vietnam, wraps itself in a leaf before dropping to the forest floor. It then spends three days searching for a suitable place to pupate, despite not being able to see out of its shelter. Experts found the insect used a piston-like motion to jump away from strong sunlight. "We believe the object of the jumping is to find shade - to avoid overheating and desiccation," explained Mr Kim Humphreys from the Royal Ontario Museum, Canada who conducted the research alongside Dr Christopher Darling. Their findings are published in the Royal Society journal Biology Letters. Although Mr Humphreys described the caterpillar as "non-descript" in appearance, he said its behaviour makes it unique in a number of ways. "Caterpillars or larvae that jump are rare in themselves," he said. "[This] caterpillar is remarkable for its jumping, which no other insect does in this way. It also makes its own vehicle [or] shelter to jump in." "It is also the only one I know of that jumps in an oriented way." BBC © 2013

Keyword: Animal Migration; Vision
Link ID: 18539 - Posted: 08.21.2013

by Ed Yong In the image above, all the eggs in the top row are laid by cuckoos and those in the bottom row belong to their victims. These uncanny similarities help cuckoos to fob off their parental duties by laying their eggs in the nests of other species. If the hosts can’t tell the difference between their eggs and the foreign ones, they’ll end up raising the cuckoo chick as their own. And they pay a hefty price for their gullibility, since cuckoo chicks often kill or outcompete their foster siblings. The relationship between cuckoos and their hosts is a classic example of an evolutionary arms race. Cuckoos, should evolve eggs that more closely match those of their hosts, while the hosts should evolve keener senses to discriminate between their own eggs and a cuckoo’s. The greater honeyguide isn’t a cuckoo but uses the same tactics—it parasitises the nests of little bee-eaters by laying eggs of the same size and shape. But this mimicry doesn’t help it to fool the bee-eaters, which seem to accept any old egg no matter how different it looks. Instead, Claire Spottiswoode from the University of Cambridge has found that the parasitic honeyguides are fighting an evolutionary arms race against… each other. Bee-eaters build their nests underground, usually within abandoned aardvark burrows. When honeyguides invade, they’ll puncture the bee-eater’s eggs before laying their own. This kills some of the eggs outright and weakens others. If any chicks survive to hatching, they’re finished off by the honeyguide chick, which stabs its foster siblings to death with a vicious hooked bill.

Keyword: Sexual Behavior; Evolution
Link ID: 18538 - Posted: 08.21.2013

By Jessica Shugart People who need sugary snacks to stay sharp throughout the day could be prisoners of their own beliefs. The brain works just fine without regular shots of sugar in people who believe their willpower is unlimited, a new study shows. “There's a dominant theory in psychology that willpower is limited, and whenever you exert yourself to do a hard task or to resist a temptation, you deplete this limited resource,” says psychologist Carol Dweck from Stanford University. Previous studies have shown that mental exertion diminishes blood glucose levels and that a person’s willpower can be rejuvenated by ingesting a sugary drink. But Dweck’s earlier work led her to suspect that people’s attitudes about willpower may be responsible for that effect. In the new study, published online August 19 in the Proceedings of the National Academy of Sciences, Dweck, along with colleagues at the University of Zurich in Switzerland, focused on how attitudes about willpower may shape a person’s sugar dependence in the face of a challenge. The scientists also tested whether altering these beliefs might liberate a person from such a calorie-rich requirement. In the first of three experiments, the researchers asked students about their attitudes on willpower, then gave them lemonade sweetened with either sugar or a sugar substitute. Ten minutes after downing the sweet beverage, the students took tests of self-control and mental acuity. The students who subscribed to a self-generating belief about unlimited willpower scored equally well whether their drinks contained sugar or not. But the students who felt willpower was limited needed sugar to perform as well as the other group did. © Society for Science & the Public 2000 - 2013

Keyword: Attention; Obesity
Link ID: 18537 - Posted: 08.20.2013

Louis Herman The mournful, curiously repetitious yet ever-changing songs of male humpback whales have long puzzled scientists. The tunes are part of the males’ mating displays, but researchers don’t know their exact function, or which males in a population are doing the singing. Now, scientists who’ve been studying the giant marine mammals in Hawaii for almost 40 years report that even sexually immature males join older males in singing, apparently as a way to learn the music and to amplify the song. The beefed-up, all-male choruses may attract more females to the areas where the songsters hang out. Scientists generally thought that only adult male humpbacks (Megaptera novaeangliae) sing, says Louis Herman, a marine mammal biologist emeritus at the University of Hawaii, Manoa, and the lead author of the new study. “But that’s just because you can’t easily tell which ones are mature and which ones are immature,” he says. “We know that mature males are larger than immature ones, so we had to figure out an unobtrusive way to measure them in the open ocean.” Herman and his team hit on a technique by looking at 20th century whaling records. Biologists with whaling operations in the Southern Ocean had the opportunity to measure many humpbacks killed during the commercial hunts. They determined, based on the weight of males’ testes, that the whales reached sexual maturity at a body length of 11.2 meters. Working independently, whaling biologists in Japan, who also measured killed whales, reached a similar conclusion; they described 11.3 meters as the break point between adolescents and adults. © 2012 American Association for the Advancement of Science

Keyword: Sexual Behavior; Animal Communication
Link ID: 18536 - Posted: 08.20.2013

Karen Ravn The authors of a new study write that this plant bug, Coridromius tahitiensis, “lacks precopulatory courtship, and males instead pounce on nearby females, with whom they struggle violently in their attempt to mate.” If you lived on an exotic island where unsafe sex was all too common, you'd find ways to ward off unwanted attention. On Tahiti, the females of two related insect species have had to move their genitals to different sides of their bodies and even impersonate the opposite sex — all to avoid getting pierced in the abdomen by the sexual organs of the wrong males, biologists report. The two insects, which live side by side on the Pacific island of Tahiti and feed on the same plants, are known as Coridromius tahitiensis and Coridromius taravao. Both species follow the aptly named practice of traumatic insemination. With his genital organ reminiscent of a hypodermic needle, the male stabs a female in the side and shoots sperm into her abdomen. The ritual — shared by a number of other invertebrates, including bedbugs (Cimex lectularius) — can cause injury or infection for the female. Not only that, but insects that use this type of reproductive method are not particularly persnickety about partners, so a male of one species may try to mate with another male — or even with a member of another species. Such interspecies mating can be costly to both species in terms of wasted time, energy and sperm, says Nikolai Tatarnic, a biologist who is now curator of insects at the Western Australian Museum in Welshpool. © 2013 Nature Publishing Group,

Keyword: Sexual Behavior; Evolution
Link ID: 18535 - Posted: 08.20.2013

by Douglas Main, LiveScience Staff Writer Rock-a-bye owlet, in the treetop … Baby owls and baby mammals, including humans, sleep in an analogous manner, spending a similar amount of time in an awakelike phase called REM (rapid-eye movement), in which dreams are thought to occur, at least during adulthood, new research suggests. In both owls and humans, REM sleep decreases with increasing age. Baby humans spend about 50 percent of their snooze time in this REM phase, whereas that figure decreases to less than 25 percent in adults, according to a statement from the Max Planck Institute for Ornithology. (Applying the REM term to owls, whose eyes are fixed in their heads, may seem a stretch, but researchers use the phrase anyway.) In the new study, published in July in the journal Frontiers in Zoology, the researchers attached electroencephalograms (EEGs) and movement data loggers to 66 young barn owls to record how much time the animals spent in REM sleep and how much they moved while snoozing. They later removed the EEGs, which measure brain waves, and found that the birds mated normally and didn't appear to have suffered any negative effects from the devices, the statement noted. (7 Ways Animals Act Like Humans) "During this sleep phase, the owlets' EEG showed awakelike activity, their eyes remained closed, and their heads nodded slowly," said University of Lausanne researcher Madeleine Scriba in the statement. © 2013 Discovery Communications, LLC.

Keyword: Sleep; Development of the Brain
Link ID: 18534 - Posted: 08.20.2013

By Scicurious It’s something we feel we’ve always known: if you can’t sleep, you need to exercise more. Wear yourself out, make yourself good and tired, you’ll sleep like a baby! So when I started having trouble sleeping, I just figured I needed to work out more. Of course, it kind of figures that often, you have trouble sleeping because of life stress, which often means you’re really busy, which in turn means it probably puts MORE stress in your life just trying to find the time to work out. But that’s just details. So sometimes, when I catch myself constantly waking up in a panic over several days, I’ll fit in some hard exercise. Maybe I’ll go for a long run, or try a really hard new class or something. By the time I go to bed I am WIPED. Physically and mentally. My body is so exhausted that the feeling of lying down is one of total bliss. …so why can’t I SLEEP?!?! Turns out I was suffering under expectations that were a little too high for reality. First off, we’re not wrong. Exercise DOES improve sleep. It does. But not necessarily immediately. And perhaps, instead, we should ask a different question. Instead of asking how exercise impacts sleep, perhaps we should ask how sleep impacts exercise. The authors of this study were looking at exercise and sleep, especially in the elderly. We all sleep less as we get older, but chronic insomnia is a different beast entirely. When we don’t get enough sleep, we get snappish, have trouble concentrating, suffer from daytime sleepiness, and are more susceptible to things like getting sick, or getting in to accidents. © 2013 Scientific American

Keyword: Sleep
Link ID: 18533 - Posted: 08.20.2013

By James Gallagher Health and science reporter, BBC News A lifetime of too much copper in our diets may be contributing to Alzheimer's disease, US scientists say. However, research is divided, with other studies suggesting copper may actually protect the brain. The latest study in Proceedings of the National Academy of Sciences showed high levels of copper left the brain struggling to get rid of a protein thought to cause the dementia. Copper is a vital part of our diet and necessary for a healthy body. Tap water coming through copper pipes, red meat and shellfish as well as fruit and vegetables are all sources of dietary copper. Barrier The study on mice, by a team at the University of Rochester in New York, suggested that copper interfered with the brain's shielding - the blood brain barrier. Mice that were fed more copper in their water had a greater build-up of the metal in the blood vessels in the brain. The team said this interfered with the way the barrier functioned and made it harder for the brain to get rid of a protein call beta amyloid. One of the hallmarks of Alzheimer's disease is the formation of plaques of amyloid in the dying brain. Lead researcher Dr Rashid Deane said: "It is clear that, over time, copper's cumulative effect is to impair the systems by which amyloid beta is removed from the brain." BBC © 2013

Keyword: Alzheimers; Neurotoxins
Link ID: 18532 - Posted: 08.20.2013