By Kai Kupferschmidt One of the main targets in the war on drugs could well become a drug to treat the scars of war. The U.S. Food and Drug Administration (FDA) has designated 3,4-methylenedioxymethamphetamine (MDMA), better known as the illegal drug ecstasy, a "breakthrough therapy" for posttraumatic stress disorder (PTSD), a status that may lead to faster approval. The agency has also approved the design for two phase III studies of MDMA for PTSD that would be funded by the Multidisciplinary Association for Psychedelic Studies (MAPS), a nonprofit in Santa Cruz, California. MAPS announced the "breakthrough therapy" designation, made by FDA on 16 August, on its website today; if the group can find the money for the trials, which together could cost an estimated $25 million, they may start next spring and finish by 2021. That an illegal dancefloor drug could become a promising pharmaceutical is another indication that the efforts of a dedicated group of researchers interested in the medicinal properties of mind-altering drugs is paying dividends. Stringent drug laws have stymied research on these compounds for decades. "This is not a big scientific step," says David Nutt, a neuropsychopharmacologist at Imperial College London. "It’s been obvious for 40 years that these drugs are medicines. But it’s a huge step in acceptance." Since 2012, FDA has designated close to 200 drugs as breakthrough therapies, a status that indicates there’s preliminary evidence that an intervention offers a substantial improvement over other options for a serious health condition. The agency aims to help develop and review these treatments faster than other candidate drugs. © 2017 American Association for the Advancement of Science

Keyword: Stress; Drug Abuse
Link ID: 24006 - Posted: 08.28.2017

By Aylin Woodward If you’re trying to overthrow the boss, you might need a friend to back you up. The same is true for female macaques, who need allies to resist authority and take down more powerful members of the group. Most primates have social hierarchies in which some individuals are dominant over the others. For rhesus macaques, these strict hierarchies are organised around female relationships. Lower-ranked females have little social mobility and must silently bare their teeth to higher-ranked females. The signal means “I want you to know that I know that you out-rank me” and is important in communicating social rank, says Darcy Hannibal at the University of California, Davis. “They are ‘bending the knee’.” But Hannibal and her colleagues have discovered that subordinate females can override the status quo. To do this, female macaques form alliances with family, friends or both. These alliances help females maintain or increase their social rank and compete for resources. A female who wants to challenge those higher up needs this help, says Hannibal. Insubordination events were more likely if the lower-ranked female was older. They were most likely if the subordinate outweighed the dominant female by 7 kilograms and the dominant female had no family allies. The more allies the subordinate female had, and the more days her mother was present in the group, the more often she would exhibit insubordinate behaviour. © Copyright New Scientist Ltd.

Keyword: Aggression; Sexual Behavior
Link ID: 24005 - Posted: 08.28.2017

By Andy Coghlan How and when did we first become able to speak? A new analysis of our DNA reveals key evolutionary changes that reshaped our faces and larynxes, and which may have set the stage for complex speech. The alterations were not major mutations in our genes. Instead, they were tweaks in the activity of existing genes that we shared with our immediate ancestors. These changes in gene activity seem to have given us flat faces, by retracting the protruding chins of our ape ancestors. They also resculpted the larynx and moved it further down in the throat, allowing our ancestors to make sounds with greater subtleties. The study offers an unprecedented glimpse into how our faces and vocal tracts were altered at the genetic level, paving the way for the sophisticated speech we take for granted. However, other anthropologists say changes in the brain were at least equally important. It is also possible that earlier ancestors could speak, but in a more crude way, and that the facial changes simply took things up a notch. Liran Carmel of the Hebrew University of Jerusalem and his colleagues examined DNA from two modern-day people and four humans who lived within the last 50,000 years. They also looked at extinct hominins: two Neanderthals and a Denisovan. Finally, they looked at genetic material from six chimpanzees and data from public databases supplied by living people. © Copyright New Scientist Ltd.

Keyword: Language; Evolution
Link ID: 24004 - Posted: 08.28.2017

By Jocelyn Kaiser The National Institutes of Health (NIH) in Bethesda, Maryland, has confirmed that the agency’s definition of clinical trials now includes imaging studies of normal brain function that do not test new treatments. The change will impose new requirements that many researchers say don’t make sense and could stifle cognitive neuroscience. Although NIH revised its definition of clinical trials in 2014, the agency is only now implementing it as part of a new clinical trials policy. Concerns arose this summer when an NIH official said the definition could apply to many basic behavioral research projects, including brain studies—for example, having healthy volunteers perform a computer task while wearing an electrode cap or lying in an MRI machine. Scientists say the new requirements—such as training and registration on clinicaltrials.gov—are unnecessary, will impose a huge paperwork burden, and will confuse patients seeking to enroll in trials. NIH told ScienceInsider in July that the agency was still deciding exactly which behavioral studies would be covered by the new definition. On 11 August, the agency released a set of case studies that has confirmed many researchers’ fears. Case No. 18 states that a study in which a healthy volunteer undergoes MRI brain imaging while performing a working memory test is now a clinical trial because the effect being evaluated—brain function—is a health-related outcome. © 2017 American Association for the Advancement of Science

Keyword: Brain imaging
Link ID: 24003 - Posted: 08.26.2017

Andrea Hsu Dan Fabbio was 25 and working on a master's degree in music education when he stopped being able to hear music in stereo. Music no longer felt the same to him. When he was diagnosed with a brain tumor, he immediately worried about cancer. Fortunately, his tumor was benign. Unfortunately, it was located in a part of the brain known to be active when people listen to and make music. Fabbio told his surgeon that music was the most important thing is his life. It was his passion as well as his profession. His surgeon understood. He's someone whose passion has been mapping the brain so he can help patients retain as much function as possible. Dr. Web Pilcher, chair of the Department of Neurosurgery at the University of Rochester Medical Center, and his colleague Brad Mahon, a cognitive neuroscientist, had developed a brain mapping program. Since 2011, they've used the program to treat all kinds of patients with brain tumors: mathematicians, lawyers, a bus driver, a furniture maker. Fabbio was their first musician. The idea behind the program is to learn as much as possible about the patient's life and the patient's brain before surgery to minimize damage to it during the procedure. "Removing a tumor from the brain can have significant consequences depending upon its location," Pilcher says. "Both the tumor itself and the operation to remove it can damage tissue and disrupt communication between different parts of the brain." © 2017 npr

Keyword: Hearing; Pain & Touch
Link ID: 24002 - Posted: 08.26.2017

Darby Saxbe Postpartum depression has become more visible as celebrity moms including Brooke Shields, Drew Barrymore and Chrissy Teigen have publicly shared their struggles with feeling sad and hopeless after birth. But when a father – Adam Busby, from reality TV show “OutDaughtered” – recently opened up about his own postpartum depression, he received instant backlash, including comments telling him to “man up.” Despite the skepticism, postpartum depression in fathers is very real, with estimates that around 10 percent of men report symptoms of depression following the birth of a child, about double the typical rate of depression in males. Postpartum depression in women has been linked with hormonal shifts, but the role of hormones in men’s postpartum depression has been unknown. In an attempt to solve this mystery, my colleagues and I recently tested whether men’s levels of the hormone testosterone are related to their postpartum depression risk during early parenthood. We found that men’s testosterone levels might predict not only their own postpartum depression risk, but their partner’s depression risk as well. Testosterone is an androgen hormone, responsible for the development and maintenance of male secondary sex characteristics. It promotes muscle mass and body hair growth, and motivates sexual arousal and competitive behavior. Many studies have found that testosterone dips in new fathers across the animal kingdom. Among animals that engage in the biparental care of offspring – Mongolian gerbils, Djungarian hamsters, California mice and cotton-top tamarins – males show lower testosterone levels following the birth of pups. © 2010–2017, The Conversation US, Inc.

Keyword: Depression; Hormones & Behavior
Link ID: 24001 - Posted: 08.26.2017

By Elizabeth Pennisi GRONINGEN, THE NETHERLANDS—For insects such as the tobacco budworm moth, beauty is actually in the “nose” of the beholder, as females use chemical scents called pheromones to lure in potential mates. And—as in people—some moths are attractive. Others … well, not so much. Now, evolutionary biologists have learned that these unattractive female moths better their odds of mating by hanging out with their more attractive counterparts. “We often think of mate choice as a perfect and entirely binary process—you are attractive or you are not—but this is clearly not the case,” says Therésa Jones, a behavioral and evolutionary ecologist at the University of Melbourne in Australia, who was not involved with the work. Wouter Halfwerk, a behavioral ecologist at the University of Amsterdam, adds that the results, reported this week here at the XIV Congress of the European Society of Evolutionary Biology, “provide an answer of how unattractiveness can evolve, which challenges our notion of beauty.” The new work was done by Astrid Groot, an evolutionary biologist at the University of Amsterdam who studies the evolution of sexual signals. She specializes in the tobacco budworm moth (Heliothis virescens) because so much is already known about its caterpillar, a widespread crop pest in the United States often caught by farmers with pheromone-scented traps. In field studies, she and other researchers noticed that some females never seem to attract males. But how could they reproduce enough to pass along their less-than-sexy scent? To find out, she and colleagues raised multiple generations of the budworm in the lab, testing each generation’s females for how quickly males home in on their scents. By separately breeding the most and least attractive females, the researchers gradually created two strains, one of supersexy smellers and one of, for lack of a better word, stinkers. © 2017 American Association for the Advancement of Science

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 24000 - Posted: 08.26.2017

Nicola Davis An article suggesting that sugar should be considered an addictive substance, and could even be on a par with abusive drugs such as cocaine, has sparked a furious backlash with experts describing the claims as “absurd”. In a narrative review published in the British Journal of Sports Medicine the authors write that sugar could act as a gateway to alcohol and other addictive substances, adding that like sugar, like cocaine and opium, is refined from plants to yield pure white crystals – a process they say “significantly adds to its addictive properties.” Too much sugar could increase depression risk in men, study suggests Read more The article was co-authored by cardiovascular research scientist James J DiNicolantonio and cardiologist James H O’Keefe, both from Saint Luke’s Mid America Heart Institute in Kansas, together with William Wilson – a physician with the nonprofit US group practice Lahey Health. “Consuming sugar produces effects similar to that of cocaine, altering mood, possibly through its ability to induce reward and pleasure, leading to the seeking out of sugar,” they write, citing rodent studies which show that sweetness is preferred even over cocaine, and that mice can experience sugar withdrawal. Speaking to the Guardian, DiNicolantonio said that the consumption of sugar was a grave concern. “In animals, it is actually more addictive than even cocaine, so sugar is pretty much probably the most consumed addictive substance around the world and it is wreaking havoc on our health.” © 2017 Guardian News and Media Limited

Keyword: Drug Abuse; Obesity
Link ID: 23999 - Posted: 08.26.2017

By Emily Underwood It doesn’t take long for tropical zebrafish to get hooked on hydrocodone. Within a week, they will risk their lives thousands of times per hour to get a dose of the opioid, shows the first study that let the fish themselves choose when to take a hit. To train them, researchers released 1.5 milligrams of hydrocodone per liter of water every time they swam over a shallow platform. The drug quickly filtered out of the tank, so they had to keep going back if they wanted to maintain their high. After just 5 days, the trained fish were visiting the opioid-delivering platform almost 2000 times every 50 minutes, the team reports online today in Behavioral Brain Research. When no drug was present, they visited the platform only about 200 times. Fish normally avoid shallow water, where they’re more likely to be spotted by predators. But over and over again, the jonesing zebrafish left the safety of deep water for the shallow platform. When the team rigged the tank so it took several visits to get a hit, the fish ramped up their efforts, returning as many as 20 times for one dose. Previous studies have shown that zebrafish exposed to opioids become stressed and anxious when the drug is taken away, displaying symptoms of withdrawal. But this is the first time scientists have shown that zebrafish will expend effort—and even court danger—to get a dose. Because zebrafish and humans share the same opioid receptor in their brains, as well as neurotransmitters such as dopamine and serotonin that signal pleasure and reward, the team hopes to use them to screen for new treatments for opioid addiction. © 2017 American Association for the Advancement of Science

Keyword: Drug Abuse
Link ID: 23998 - Posted: 08.26.2017

By Helen Thomson Have you ever seen the Virgin Mary in your grilled cheese? Or a screaming face inside a bell pepper? Seeing faces in inanimate objects is a common phenomenon. Now it seems that we’re not alone in experiencing it – monkeys do too. Pareidolia is the scientific term for erroneously perceiving faces where none exist. Other examples including seeing “ghosts” in blurry photos and the man in the moon. To investigate whether pareidolia was a uniquely human experience, Jessica Taubert at the US National Institute of Mental Health in Maryland and her colleagues trained five rhesus macaques to stare at pairs of photos. Each photo showed either an inanimate object that prompts pareidolia in humans, an equivalent object that doesn’t, or the face of a monkey (below). We already knew that both people and monkeys will look longer at images of faces than other things. So the team presented each of the photos in every possible pairing – 1980 in all – and measured the time the monkeys spent looking at each. The monkeys did indeed seem to succumb to pareidolia – they spent more time looking at illusory faces than the non-illusory photos they were paired with. Interestingly, they also spent more time looking at the illusory faces than the monkey faces, perhaps because they spent longer studying these more unusual “faces”, or because they tend to dislike holding the gaze of another monkey. © Copyright New Scientist Ltd.

Keyword: Attention
Link ID: 23997 - Posted: 08.25.2017

Jon Hamilton It's not just what you say that matters. It's how you say it. Take the phrase, "Here's Johnny." When Ed McMahon used it to introduce Johnny Carson on The Tonight Show, the words were an enthusiastic greeting. But in The Shining, Jack Nicholson used the same two words to convey murderous intent. Now scientists are reporting in the journal Science that they have identified specialized brain cells that help us understand what a speaker really means. These cells do this by keeping track of changes in the pitch of the voice. "We found that there were groups of neurons that were specialized and dedicated just for the processing of pitch," says Dr. Eddie Chang, a professor of neurological surgery at the University of California, San Francisco. Chang says these neurons allow the brain to detect "the melody of speech," or intonation, while other specialized brain cells identify vowels and consonants. "Intonation is about how we say things," Chang says. "It's important because we can change the meaning, even — without actually changing the words themselves." For example, by raising the pitch of our voice at the end of a sentence, a statement can become a question. The identification of neurons that detect changes in pitch was largely the work of Claire Tang, a graduate student in Chang's lab and the Science paper's lead author. Tang and a team of researchers studied the brains of 10 epilepsy patients awaiting surgery. The patients had electrodes placed temporarily on the surface of their brains to help surgeons identify the source of their seizures. © 2017 npr

Keyword: Language
Link ID: 23996 - Posted: 08.25.2017

By Frank Swain When you search for a medical condition online, would you also want to take a test for it then and there? Google has announced plans to offer people in the US searching for “depression” a clinically validated questionnaire so they can find out if they may have the condition. But then what? “This sounds like a really good idea that can quickly help people work out whether they are having low moods or feeling blue, [or if they] may have more serious and enduring problems that could be alleviated by seeking help,” says Marjorie Wallace, of the UK mental health charity SANE. “Our concern [however] is that raising expectations of help can be disappointing.” In places where access to therapy is hard to come by, a questionnaire may offer little comfort. Google has partnered with the National Alliance on Mental Illness (NAMI) – a US advocacy group for those affected by mental illness – to provide a link to a depression questionnaire at the top of the search results for terms related to depression. In an announcement posted on Google’s blog, NAMI states that the results of the self-assessment can form the first step towards a diagnosis, and help people have a more informed conversation with their doctor. © Copyright New Scientist Ltd.

Keyword: Depression
Link ID: 23995 - Posted: 08.25.2017

By Sameer Deshpande, Raiden Hasegawa, Christina Master, Amanda Rabinowitz, Dylan Small American football is the largest participation sport in U.S. high schools. Recently, many have expressed concern about the sport’s safety with some even calling for banning youth and high school tackle football. We recently published a study in JAMA Neurology suggesting that, in general, men who played high school football in 1950s Wisconsin did not have a higher risk of poor cognitive or emotional health later in life than those who did not play. Recent concerns about football’s safety have been driven largely by reports of chronic traumatic encephalopathy (CTE) among retired professional players. CTE is a neurodegenerative disease thought to result from repetitive head trauma with symptoms including memory loss, aggression, confusion and depression. A recent study in JAMA reported evidence of CTE in 110 of 111 deceased retired NFL players who donated their brains for posthumous examination. This important study adds to a larger body of work linking repetitive sports-related concussion with neurodegenerative disease. However, such research, which depends on brains donated by families of players many of whom were symptomatic before death, is not designed to establish the base rate of neurodegeneration among the larger population of football players. A critical question remains: what is the risk of later-life cognitive and emotional dysfunction for American high school football players? © 2017 Scientific American

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 23994 - Posted: 08.25.2017

Phil Daoust As a man – the sort of thoughtful, Fawcett Society-supporting man who lowers the toilet seat after peeing, even when he has the house to himself – it’s hard to talk about women and their hormones. There’s no doubt that they affect minds and bodies, through puberty, pregnancy and premenstrual syndrome (PMS). The National Association for Premenstrual Syndrome’s list of “common” symptoms includes mood swings, depression, tiredness, anxiety, feeling out of control, irritability, aggression, headaches, sleep disorder, food cravings, breast tenderness, bloating, weight gain and clumsiness. Men can’t and shouldn’t ignore this catalogue of woes. But there’s a fine line between commiserating and condescending. It’s too easy – and tempting – to dismiss a woman’s actions or opinions because it’s “that time of the month”. Mostly it isn’t. Many women are lucky enough to escape PMS. And even when they don’t, sometimes she’s still right and you’re still wrong. For better or worse, however, we males must now face up to our own fluctuating chemistry. We may not routinely bloat and bleed, but a new study makes it clear that we too are at the mercy of our hormones – specifically, the one produced between our legs. After testing hundreds of men, researchers from the California Institute of Technology, Wharton School, Western University and ZRT Laboratory reported (pdf) “a clear and robust causal effect of testosterone on human cognition and decision-making” © 2017 Guardian News and Media Limited

Keyword: Aggression; Hormones & Behavior
Link ID: 23993 - Posted: 08.25.2017

By Sam Wong It seems you can judge an athlete by their face – if they are a man, that is. Male athletes with a higher world ranking tend to be judged as more attractive by women, but there is no such trend among women. Several studies have previously reported a link between facial attractiveness and sporting performance in men, leading to suggestions that women respond to facial cues that reflect athletic ability in potential partners. Some have suggested this is because, in our evolutionary past, women might have benefited from choosing a partner with speed, skill and endurance. As a better hunter, the idea goes, he would have brought home more food, and he might pass on his fitness to their children. But these studies have been criticised, notably for only looking at men. They also tended to focus on team sports, therefore failing to isolate individual performance. To find more evidence, Tim Fawcett and colleagues at the University of Exeter, UK, collected photos of 156 men and women who competed at the 2014 Winter Olympics in the biathlon – an event combining cross-country skiing and shooting. Each athlete was rated for their facial attractiveness by members of the opposite sex, who didn’t know the purpose of the study. © Copyright New Scientist Ltd.

Keyword: Sexual Behavior; Evolution
Link ID: 23992 - Posted: 08.25.2017

By NICHOLAS BAKALAR Studies have shown that obese women give birth to larger babies who are at risk for obesity and other metabolic problems later in life. Some have thought that the reason may be that obese mothers, whose bodies are rich in nutrients, somehow “overfeed” the fetus during gestation. A new study has found that this is unlikely. The study, in PLOS Medicine, looked at more than 10,000 mother-child pairs, following their offspring into early adulthood. Researchers had data on body mass index, education, occupation and smoking behavior for both mothers and fathers. They also did tests for 153 metabolic traits in the children, including levels of fats in the blood. They found that both maternal and paternal B.M.I. were associated strongly with the metabolic traits of their children. Since paternal B.M.I. cannot affect the fetus during its development, this suggests that familial traits, rather than any “programming” of the fetus in the womb, are the explanation for metabolic abnormalities in the children of obese mothers. The senior author, Deborah A. Lawlor, a professor of epidemiology at the University of Bristol in England, said obesity in pregnancy is dangerous for many reasons. But the evidence that the mother’s weight alone determines her children’s future metabolic health is weak, and putting all the burden on the pregnant woman is not helpful. “The whole family should have a healthy weight,” she said. © 2017 The New York Times Company

Keyword: Obesity; Development of the Brain
Link ID: 23991 - Posted: 08.25.2017

By James Gallagher People with higher levels of lithium in their drinking water appear to have a lower risk of developing dementia, say researchers in Denmark. Lithium is naturally found in tap water, although the amount varies. The findings, based on a study of 800,000 people, are not clear-cut. The highest levels cut risk, but moderate levels were worse than low ones. Experts said it was an intriguing and encouraging study that hinted at a way of preventing the disease. The study, at the University of Copenhagen, looked at the medical records of 73,731 Danish people with dementia and 733,653 without the disease. Tap water was then tested in 151 areas of the country. The results, published in JAMA Psychiatry, showed moderate lithium levels (between 5.1 and 10 micrograms per litre) increased the risk of dementia by 22% compared with low levels (below five micrograms per litre). However, those drinking water with the highest lithium levels (above 15 micrograms per litre) had a 17% reduction in risk. The researchers said: "This is the first study, to our knowledge, to investigate the association between lithium in drinking water and the incidence of dementia. "Higher long-term lithium exposure from drinking water may be associated with a lower incidence of dementia." Lithium is known to have an effect on the brain and is used as a treatment in bipolar disorder. However, the lithium in tap water is at much lower levels than is used medicinally. Experiments have shown the element alters a wide range of biological processes in the brain. © 2017 BBC.

Keyword: Alzheimers
Link ID: 23990 - Posted: 08.24.2017

/ By Eric Bender Physicians call it the 5,000-hour problem. If you have a common chronic condition such as cardiovascular disease or diabetes, the expert in charge of your health for almost all of your 5,000 waking hours annually is — you. And, frankly, you won’t always make the best choices. “The behavior changes that are necessary to address chronic disease are much more in your hands than in the doctor’s,” points out Stacey Chang, executive director of the Design Institute for Health at Dell Medical School in Austin, Texas. “To cede that control to the doctor sometimes is actually counterproductive.” “While there have been enormous advances in technology, there’s still a lot of work to be done with the science of habit formation.” With that in mind, a rapidly evolving set of new digital health tools is angling to help patients engage better with their own care. Wearable health monitors already on the market help to track heart rate, footsteps, or blood glucose levels; sophisticated home health sensors can report on weight and blood pressure; and phone apps can present key feedback and maybe even offer personalized advice. The only problem: It has thus far proved very difficult to know what really works. Indeed, despite a veritable avalanche of “digital health” products, from Fitbits to telehealth heart sensors, and despite floods of data flowing both to the people who use them and to their physicians — and even despite clear evidence that many doctors very much want these new gadgets to work — there is still precious little clinical data proving that they are providing major patient benefits or delivering more cost-effective care. Copyright 2017 Undark

Keyword: Obesity
Link ID: 23989 - Posted: 08.24.2017

By Jessica Hamzelou People who use methamphetamine are almost five times more likely to have a stroke caused by a bleed in the brain, many of which are fatal. “We can add stroke to the list of terrible and devastating things that methamphetamine does,” says Damian Zuloaga, of the University at Albany, New York. Beyond the signature tooth decay known as “meth mouth”, methamphetamine also increases heart rate and blood pressure, and can trigger heart attacks. The drug can lead to psychosis, and has been linked to anxiety disorders, depression, and problems with movement similar to those seen in Parkinson’s disease. A handful of studies have also linked methamphetamine use to strokes. To explore further, Julia Lappin and her colleagues at the Australian National Drug and Alcohol Research Centre in Sydney sifted through published research on the topic. The team specifically looked for research into people under the age of 45 – a group less likely to be affected by age-related causes of stroke. They assessed the results of 77 studies in total. Most of these studies were conducted in the US, where, in 2012, around 1.2 million people reported using methamphetamine in the past year. Several of the studies the team looked at reported that strokes are responsible for between one and five per cent of methamphetamine-related deaths. And other studies found that methamphetamine was to blame for between two and six per cent of all strokes caused by a blockage in the brain’s blood flow in under 45s. © Copyright New Scientist Ltd.

Keyword: Drug Abuse; Stroke
Link ID: 23988 - Posted: 08.24.2017

By Matthew Hutson Engineers have figured out how to make antennas for wireless communication 100 times smaller than their current size, an advance that could lead to tiny brain implants, micro–medical devices, or phones you can wear on your finger. The brain implants in particular are “like science fiction,” says study author Nian Sun, an electrical engineer and materials scientist at Northeastern University in Boston. But that hasn’t stopped him from trying to make them a reality. The new mini-antennas play off the difference between electromagnetic (EM) waves, such as light and radio waves, and acoustic waves, such as sound and inaudible vibrations. EM waves are fluctuations in an electromagnetic field, and they travel at light speed—an astounding 300,000,000 meters per second. Acoustic waves are the jiggling of matter, and they travel at the much slower speed of sound—in a solid, typically a few thousand meters per second. So, at any given frequency, an EM wave has a much longer wavelength than an acoustic wave. Antennas receive information by resonating with EM waves, which they convert into electrical voltage. For such resonance to occur, a traditional antenna's length must roughly match the wavelength of the EM wave it receives, meaning that the antenna must be relatively big. However, like a guitar string, an antenna can also resonate with acoustic waves. The new antennas take advantage of this fact. They will pick up EM waves of a given frequency if its size matches the wavelength of the much shorter acoustic waves of the same frequency. That means that that for any given signal frequency, the antennas can be much smaller. © 2017 American Association for the Advancement of Science

Keyword: Brain imaging
Link ID: 23987 - Posted: 08.23.2017