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By EREZ YOELI and DAVID RAND Recently, three young American men and a British businessman thwarted a gunman’s attack on a French passenger train, acting within seconds and at enormous personal risk. When interviewed afterward, they stressed the unthinking nature of their actions. “It was just gut instinct,” said one, in a characteristic remark. “It wasn’t really a conscious decision.” This turns out to be typical of heroes. Last year, one of us, Professor Rand, together with his colleague Ziv Epstein, conducted an analysis of recipients of the Carnegie Medal for heroism, which is awarded to those who risk their lives for others. After collecting interviews given by 51 recipients and evaluating the transcripts, we found that the heroes overwhelming described their actions as fast and intuitive, and virtually never as carefully reasoned. This was true even in cases where the heroes had sufficient time to stop and think. Christine Marty, a college student who rescued a 69-year-old woman trapped in a car during a flash flood, said she was grateful that she didn’t take the time to reflect: “I’m thankful I was able to act and not think about it.” We found almost no examples of heroes whose first impulse was for self-preservation but who overcame that impulse with a conscious, rational decision to help. It is striking that our brute instincts, rather than our celebrated higher cognitive faculties, are what lead to such moral acts. But why would anyone ever develop such potentially fatal instincts? One possible explanation is that in most everyday situations, helping others pays off in the long run. You buy lunch for a friend or pitch in to help a colleague meet a tight deadline, and you find yourself repaid in kind, or even more, down the road. So it’s beneficial to develop a reflex to help — especially because the cost to you is usually quite small. © 2015 The New York Times Company
Link ID: 21365 - Posted: 08.31.2015
Depressed people who display "risky behaviour", agitation and impulsivity are at least 50% more likely to attempt suicide, a study has found. Research by the European College of Neuropsychopharmacology (ECNP) concluded that the behaviour patterns "precede many suicide attempts". The study said effective prevention measures were "urgently needed". The World Health Organisation estimates that there were more than 800,000 suicides worldwide in 2012. The ECNP study evaluated 2,811 patients suffering from depression, of whom 628 had previously attempted suicide. Researchers "looked especially at the characteristics and behaviours of those who had attempted suicide", and found that "certain patterns recur" before attempts. They said the risk of an attempt was "at least 50% higher" if a depressed patient displayed: "risky behaviour" such as reckless driving or promiscuous behaviour "psychomotor agitation" such as pacing around rooms or wringing their hands impulsivity - defined by the researchers as acting with "little or no forethought, reflection, or consideration of the consequences" Dr Dina Popovic, one of the report's authors, added: "We found that 'depressive mixed states' often preceded suicide attempts. "A depressive mixed state is where a patient is depressed, but also has symptoms of 'excitation', or mania." © 2015 BBC.
Link ID: 21364 - Posted: 08.31.2015
By Roni Caryn Rabin Q: Is it harmful to go on and off antidepressants a few times a year? I seem to respond quickly and quite well to S.S.R.I.'s. I don't desire to be on them long-term, but would like to use them occasionally, to get through a rough patch like a stressful quarter at work. Is it harmful to go on and off of S.S.R.I.'s a few times a year? Yes, it may be harmful. You should always start and stop medication “under a physician’s supervision. Don’t do it on your own,” said Dr. Renee Binder, president of the American Psychiatric Association. It usually takes at least four weeks for an antidepressant to take effect, and patients should give themselves several weeks to taper off a drug when ending treatment. Starting and quitting abruptly expose you to the risks of initiation and withdrawal. Also, you may not get sustained relief from your depression. Antidepressants “don’t work right away,” Dr. Binder said. “It’s the kind of medication that you have to take every single day, and it takes awhile to build up in your body before it starts working.” When starting antidepressants, patients may experience anxiety and agitation and develop other transient side effects like headaches and nausea. Teenagers need close monitoring because they may be at a higher risk of suicide when starting treatment, some studies suggest. It also may take time for your doctor to find the antidepressant and dose that’s right for you. Withdrawal can trigger troubling symptoms like nausea, dizziness and “brain zaps,” a sensation that feels like electric shocks to the head. It can also trigger psychological problems like anxiety, irritability, moodiness and changes in appetite and sleep that mimic depression or may signal a recurrence. Some patients may become paranoid or suicidal. © 2015 The New York Times Company
Link ID: 21363 - Posted: 08.31.2015
By Lily Hay Newman Mental health issues manifest in a number of ways, and they're not all behavioral. Increasingly, scientists are using speech analysis software to detect subtle changes in voice acoustics and patterns to detect or even predict potentially problematic conditions. A study published Wednesday in NPG-Schizophrenia by researchers at Columbia University Medical Center, the New York State Psychiatric Institute, and IBM's T. J. Watson Research Center found that digital speech analysis correctly predicted whether 34 youths at risk for mental illness (11 female, 23 male) would develop psychosis within 2.5 years. The system, which evaluated the study participants quarterly, correctly predicted all of their outcomes; five became psychotic. The algorithm evaluated transcripts for predictive "semantic and syntactic features" like coherence and phrase length. "These speech features predicted later psychosis development with 100% accuracy, outperforming classification from clinical interviews," the researchers wrote. Clinicians are able to accurately categorize patients as "at-risk," but within that subpopulation it is difficult to determine who will actually experience psychosis and potentially develop schizophrenia. If voice recognition software can help identify these individuals, they may be able to receive more effective care. "Computerized analysis of complex human behaviors such as speech may present an opportunity to move psychiatry beyond reliance on self-report and clinical observation toward more objective measures of health and illness in the individual patient," the researchers wrote. © 2015 The Slate Group LLC.
Link ID: 21362 - Posted: 08.31.2015
By GREGORY COWLES Oliver Sacks, the neurologist and acclaimed author who explored some of the brain’s strangest pathways in best-selling case histories like “The Man Who Mistook His Wife for a Hat,” using his patients’ disorders as starting points for eloquent meditations on consciousness and the human condition, died on Sunday at his home in Manhattan. He was 82. The cause was cancer, said Kate Edgar, his longtime personal assistant. Dr. Sacks announced in February, in an Op-Ed essay in The New York Times, that an earlier melanoma in his eye had spread to his liver and that he was in the late stages of terminal cancer. As a medical doctor and a writer, Dr. Sacks achieved a level of popular renown rare among scientists. More than a million copies of his books are in print in the United States, his work was adapted for film and stage, and he received about 10,000 letters a year. (“I invariably reply to people under 10, over 90 or in prison,” he once said.) Dr. Sacks variously described his books and essays as case histories, pathographies, clinical tales or “neurological novels.” His subjects included Madeleine J., a blind woman who perceived her hands only as useless “lumps of dough”; Jimmie G., a submarine radio operator whose amnesia stranded him for more than three decades in 1945; and Dr. P. — the man who mistook his wife for a hat — whose brain lost the ability to decipher what his eyes were seeing. Describing his patients’ struggles and sometimes uncanny gifts, Dr. Sacks helped introduce syndromes like Tourette’s or Asperger’s to a general audience. But he illuminated their characters as much as their conditions; he humanized and demystified them. © 2015 The New York Times Company
Link ID: 21361 - Posted: 08.31.2015
An experimental gene therapy reduces the rate at which nerve cells in the brains of Alzheimer’s patients degenerate and die, according to new results from a small clinical trial, published in the current issue of the journal JAMA Neurology. Targeted injection of the Nerve Growth Factor gene into the patients’ brains rescued dying cells around the injection site, enhancing their growth and inducing them to sprout new fibres. In some cases, these beneficial effects persisted for 10 years after the therapy was first delivered. Alzheimer’s is the world’s leading form of dementia, affecting an estimated 47 million people worldwide. This figure is predicted to almost double every 20 years, with much of this increase is likely to be in the developing world. And despite the huge amounts of time, effort, and money devoted to developing an effective cure, the vast majority of new drugs have failed in clinical trials. The new results are preliminary findings from the very first human trials designed to test the potential benefits of nerve growth factor (NGF) gene therapy for Alzheimer’s patients. NGF was discovered in the 1940s by Rita Levi-Montalcini, who convincingly demonstrated that the small protein promotes the survival of certain sub-types of sensory neurons during development of the nervous system. Since then, others have shown that it also promotes the survival of acetylcholine-producing cells in the basal forebrain, which die off in Alzheimer’s. © 2015 Guardian News and Media Limited
We all have days when we feel like our brain is going at a snail’s pace, when our neurons forgot to get out of bed. And psychologists have shown that IQ can fluctuate day to day. So if we’re in good health and don’t have a sleep deficit from last night’s shenanigans to blame, what’s the explanation? Sophie von Stumm, a psychologist at Goldsmiths University, London, set about finding out. In particular, she wanted to know whether mood might explain the brain’s dimmer switch. Although it seems intuitively obvious that feeling low could compromise intellectual performance, von Stumm says research to date has been inconclusive, with some studies finding an effect and others not. “On bad mood days, we tend to feel that our brains are lame and work or study is particularly challenging. But scientists still don’t really know if our brains work better when we are happy compared to when we are sad.” To see if she could pin down mood’s effect on IQ more convincingly, von Stumm recruited 98 participants. Over five consecutive days they completed questionnaires to assess their mood, as well as tests to measure cognitive functions, such as short-term memory, working memory and processing speed. Surprisingly, being in a bad mood didn’t translate into worse cognitive performance. However, when people reported feeling positive, von Stumm saw a modest boost in their processing speed. © Copyright Reed Business Information Ltd.
By Claire Asher If you stuck to Aesop’s fables, you might think of all ants as the ancient storyteller described them—industrious, hard-working, and always preparing for a rainy day. But not every ant has the same personality, according to a new study. Some colonies are full of adventurous risk-takers, whereas others are less aggressive about foraging for food and exploring the great outdoors. Researchers say that these group “personality types” are linked to food-collecting strategies, and they could alter our understanding of how social insects behave. Personality—consistent patterns of individual behavior—was once considered a uniquely human trait. But studies since the 1990s have shown that animals from great tits to octopuses exhibit “personality.” Even insects have personalities. Groups of cockroaches have consistently shy and bold members, whereas damselflies have shown differences in risk tolerance that stay the same from grubhood to adulthood. To determine how group behavior might vary between ant colonies, a team of researchers led by Raphaël Boulay, an entomologist at the University of Tours in France, tested the insects in a controlled laboratory environment. They collected 27 colonies of the funnel ant (Aphaenogaster senilis) and had queens rear new workers in the lab. This meant that all ants in the experiment were young and inexperienced—a clean slate to test for personality. The researchers then observed how each colony foraged for food and explored new environments. They counted the number of ants foraging, exploring, or hiding during set periods of time, and then compared the numbers to measure the boldness, adventurousness, and foraging efforts of each group. © 2015 American Association for the Advancement of Science
Link ID: 21358 - Posted: 08.29.2015
They are rather diminutive to be kings of the jungle, but two species of mirid bug make sounds similar to the roars of big cats. These calls have never before been heard in insects, and we’re not sure why, or how, the insects produce the eerie calls. The roars are too weak to be heard by humans without a bit of help. But Valerio Mazzoni of the Edmund Mach Foundation in Italy and his team made them audible by amplifying them using a device called a laser vibrometer. The device detects the minute vibrations that the bugs produce on the leaves on which they live. “When you listen to these sounds through headphones you’d think you were next to a tiger or lion,” Mazzoni. The team found that when two males were introduced on the same leaf, they seemed to compete in roaring duets. When one insect heard a roar, it always sounded its own, apparently in response. This suggests that, as in big cats, the roars might serve to establish dominance or attract females. Female mirids don’t seem to roar. But unlike the roars of big cats, the sounds produced by bugs are transmitted through the solid material beneath their feet, usually a leaf, rather than by the vibration of air molecules. Thousands of insect species communicate through such vibration, but these roars are unlike any other known insect noise. © Copyright Reed Business Information Ltd.
Raiding the fridge or downing glasses of water after a night of heavy drinking won't improve your sore head the next day, Dutch research suggests. Instead, a study concluded, the only way to prevent a hangover is to drink less alcohol. More than 800 students were asked how they tried to relieve hangover symptoms, but neither food nor water was found to have any positive effect. The findings are being presented at a conference in Amsterdam. A team of international researchers from the Netherlands and Canada surveyed students' drinking habits to find out whether hangovers could be eased or if some people were immune to them. Among 826 Dutch students, 54% ate food after drinking alcohol, including fatty food and heavy breakfasts, in the hope of staving off a hangover. With the same aim, more than two-thirds drank water while drinking alcohol and more than half drank water before going to bed. Although these groups showed a slight improvement in how they felt compared with those who hadn't drunk water, there was no real difference in the severity of their hangovers. Previous research suggests that about 25% of drinkers claim never to get hangovers. So the researchers questioned 789 Canadian students about their drinking in the previous month and the hangovers they experienced, finding that those who didn't get a hangover simply consumed "too little alcohol to develop a hangover in the first place". Of those students who drank heavily, with an estimated blood alcohol concentration of more than 0.2%, almost no-one was immune to hangovers. © 2015 BBC.
Keyword: Drug Abuse
Link ID: 21356 - Posted: 08.29.2015
By BENEDICT CAREY The past several years have been bruising ones for the credibility of the social sciences. A star social psychologist was caught fabricating data, leading to more than 50 retracted papers. A top journal published a study supporting the existence of ESP that was widely criticized. The journal Science pulled a political science paper on the effect of gay canvassers on voters’ behavior because of concerns about faked data. Now, a painstaking yearslong effort to reproduce 100 studies published in three leading psychology journals has found that more than half of the findings did not hold up when retested. The analysis was done by research psychologists, many of whom volunteered their time to double-check what they considered important work. Their conclusions, reported Thursday in the journal Science, have confirmed the worst fears of scientists who have long worried that the field needed a strong correction. The vetted studies were considered part of the core knowledge by which scientists understand the dynamics of personality, relationships, learning and memory. Therapists and educators rely on such findings to help guide decisions, and the fact that so many of the studies were called into question could sow doubt in the scientific underpinnings of their work. “I think we knew or suspected that the literature had problems, but to see it so clearly, on such a large scale — it’s unprecedented,” said Jelte Wicherts, an associate professor in the department of methodology and statistics at Tilburg University in the Netherlands. More than 60 of the studies did not hold up. Among them was one on free will. It found that participants who read a passage arguing that their behavior is predetermined were more likely than those who had not read the passage to cheat on a subsequent test. © 2015 The New York Times Company
Link ID: 21355 - Posted: 08.28.2015
by Bethany Brookshire You’ve already had a muffin. And a half. You know you’re full. But there they are, fluffy and delicious, waiting for the passersby in the office. Just thinking about them makes your mouth water. Maybe if you just slice one into quarters. I mean, that barely counts… And then we give in, our brains overriding our body’s better judgment. When I catch myself once again polishing off a whole plate of baked goods, I wish that there was something I could do, some little pill I could take that would make that last delicious bite look — and taste — a little less appealing. But the more scientists learn about the human body, the more they come to understand that there is no one set of hormones for hungry, with a separate set that kicks off your ice cream binge. Instead, our guts and their hormones are firmly entwined with our feelings of reward and motivation. That close relationship shows just how important it is to our bodies to keep us fed, and how hard it is to stop us from overeating. Researchers have long divided our feeding behavior into two distinct categories. One, the homeostatic portion, is primarily concerned with making sure we’ve got enough energy to keep going and is localized to the lateral hypothalamus in the brain. The reward-related, or “hedonic,” component is centralized in the mesolimbic dopamine system, areas of the brain usually referenced when we talk about the effects of sex, drugs and rock ’n’ roll. © Society for Science & the Public 2000 - 2015
By Diana Kwon Each year doctors diagnose approximately 60,000 Americans with Parkinson’s disease, an incurable neurodegenerative condition for which the number-one risk factor is age. Worldwide an estimated seven to 10 million people currently live with the malady. As U.S. and global populations grow older, it is becoming increasingly urgent to understand its causes. So far, researchers know that Parkinson’s involves cell death in a few restricted areas of the brain including the substantia nigra (SNc), one of two big cell clusters in the midbrain that house a large population of dopamine neurons. These cells release dopamine and are involved in a variety of functions including reward processing and voluntary movement. Their death leads to the motor control and balance issues that are core symptoms of the disease. New research shows that these brain cells, most at risk in Parkinson’s disease, require unusually high amounts of energy to carry out their tasks because of their highly branched structures. Like a massive car with an overheating engine, these neurons are susceptible to burnout and early death. This discovery emerged from a comparison of energy use in nigral dopamine neurons and in similar neurons found in the nearby ventral tegmental area (VTA), also in the midbrain. “We were trying to understand why dopamine neurons of the substantia nigra die in Parkinson’s disease patients while there are so many other brain cells that have no problem at all,” says Louis-Eric Trudeau, a neuroscientist at the University of Montreal and senior author of the study published in the August 27 Current Biology. © 2015 Scientific American,
Link ID: 21353 - Posted: 08.28.2015
By Amy Ellis Nutt Magnetic pulses from a device applied to the head appear to "reset" the brains of depressed patients, according to a new study from the United Kingdom. The circuitry in a part of the right prefrontal cortex is known to be too active in depressed patients, causing excessive rumination and self absorption and impaired attention. When the TMS was applied to healthy subjects in this study, the activity in that region slowed. "We found that one session of TMS modifies the connectivity of large-scale brain networks, particularly the right anterior insula, which is a key area in depression," lead scientist Sarina Iwabuchi, told the European College of Neuropsychology at a conference in Amsterdam this week. This was the first time an MRI was used to guide the TMS impulses and, at the same, time measure subtle changes in brain circuit activity. In addition, the researchers used magnetic resonance spectroscopy to analyze subjects' brain chemistry. "We also found that TMS alters concentrations of neurotransmitters. Iwabuchi said, "which are considered important for the development of depression," and which are the targets of most current antidepressant medications. Transcranial Magnetic Stimulation is the use of an electromagnetic coil to deliver small, powerful bursts of energy to targeted areas known to be involved in mood regulation. It is a painless, non-invasive treatment than involves no drugs, no IVs, or any other kind of sedation, and whose chief possible side effect is a headache. (The Food and Drug Administration approved limited use of TMS in 2008 for the treatment of depression.)
Link ID: 21352 - Posted: 08.28.2015
Nell Greenfieldboyce Picking a mate can be one of life's most important decisions. But sometimes people make a choice that seems to make no sense at all. And humans aren't the only ones — scientists have now seen apparently irrational romantic decisions in frogs. Little tungara frogs live in Central America, and they're found everywhere from forests to ditches to parking lot puddles. These frogs are only about 2 centimeters long, but they are loud. The males make calls to woo the females. Amanda Lea, a biologist in the laboratory of Mike Ryan at the University of Texas, Austin, says past studies have given scientists a pretty good idea of what the females find appealing. "They tend to like longer calls. They also like lower-frequency calls," says Lea. "Then, the other thing that's a really big one for these gals is the 'call rate.' They love faster call rates. The faster a male can call, the better." But in real life, love is complicated. Female frogs face countless suitors. So Lea and Ryan wondered: Would a female really always pick the male that scored highest on the froggy love-call meter? To find out, they put female frogs in a room with some loudspeakers. From one speaker the scientists played a recording of frog call that had a really fast rate. But other features in this voice were less attractive. Then the researchers played a second, different call for the female frogs. This voice was more attractive, but it was slower. The ladies had to make a choice. "They have two traits to evaluate," Lea explains. "They have the call rate and they have the attractiveness of the call." © 2015 NPR
By Dina Fine Maron Whenever the fictional character Popeye the Sailor Man managed to down a can of spinach, the results were almost instantaneous: he gained superhuman strength. Devouring any solid object similarly did the trick for one of the X-Men. As we age and begin to struggle with memory problems, many of us would love to reach for an edible mental fix. Sadly, such supernatural effects remain fantastical. Yet making the right food choices may well yield more modest gains. A growing body of evidence suggests that adopting the Mediterranean diet, or one much like it, can help slow memory loss as people age. The diet's hallmarks include lots of fruits and vegetables and whole grains (as opposed to ultrarefined ones) and a moderate intake of fish, poultry and red wine. Dining mainly on single ingredients, such as pumpkin seeds or blueberries, however, will not do the trick. What is more, this diet approach appears to reap brain benefits even when adopted later in life—sometimes aiding cognition in as little as two years. “You will not be Superman or Superwoman,” says Miguel A. Martínez González, chair of the department of preventive medicine at the University of Navarra in Barcelona. “You can keep your cognitive abilities or even improve them slightly, but diet is not magic.” Those small gains, however, can be meaningful in day-to-day life. Scientists long believed that altering diet could not improve memory. But evidence to the contrary started to emerge about 10 years ago. © 2015 Scientific American
Link ID: 21350 - Posted: 08.28.2015
By Emily Underwood It is famous for robbing Lou Gehrig of his life and Stephen Hawking of his mobility and voice, but just how amyotrophic lateral sclerosis (ALS) destroys motor neurons in the brain and spinal cord remains a mystery. Now, scientists are converging on an explanation, at least for a fraction of the ALS cases caused by a specific mutation. In cells with the mutation, the new work shows, pores in the membrane separating the nucleus and cytoplasm become clogged, preventing vital molecules from passing through and creating a fatal cellular traffic jam. For now, the work applies only to the mutation dubbed C9orf72—a DNA stutter in which a short nucleotide sequence, GGGGCC, is repeated hundreds to thousands of times in a gene on chromosome 9. Nor do the multiple labs reporting results this week agree on exactly what plugs those nuclear pores and how the cells die. Still, the work is “a major breakthrough” in ALS research, says Amelie Gubitz, program director of the neurodegeneration division at the National Institute of Neurological Disorders in Bethesda, Maryland. The groups worked independently, starting with different hypotheses and experimental designs, yet reached similar conclusions, making the finding more convincing. And it suggests that boosting traffic through nuclear pores could be a new strategy for treating some cases of ALS and frontotemporal dementia (FTD), another neurodegenerative condition C9orf72 can cause. Based on past work by their own and other groups, neuroscientists Jeff Rothstein and Tom Lloyd at Johns Hopkins University in Baltimore, Maryland, suspected that the long strands of excess RNA produced by C9orf72 cause neurodegeneration by binding to, and thus sequestering, key cellular proteins. The team tested the idea in fruit flies with the mutation, which display damage in the nerve cells of their eyes and in motor neurons. © 2015 American Association for the Advancement of Science
By Felicity Muth You might have heard of serotonin as one of the ‘happy’ hormones in humans. Indeed, mood disorders like anxiety and depression are associated with low levels of serotonin. However, this neurotransmitter also has other functions. One of the more interesting ones in humans is its role in cooperation. Lowering the serotonin levels of people increases peoples’ reactions to unfairness and makes them less cooperative. On the other hand, increasing the level of serotonin in people makes people less argumentative and more communicative and cooperative. Serotonin also plays a role in peoples’ intimate relationships, for example men and women who were fed tryptophan (necessary for serotonin production) were more likely to judge photos of couples as intimate and romantic than people who had not been fed tryptophan. Humans are of course not the only animals that form intimate relationships or cooperate with each other. One of the best examples of unrelated animals cooperating comes from cleaner fish, who form relationships with ‘clients’ (visiting reef fish) where they clean their bodies, gills and even mouths. This relationship is very cooperative: the cleaner fish would rather eat the mucus from the skin of their clients than the ectoparasites (it’s yummier, apparently), but they usually keep this particular urge under control. In return, the clients don’t eat the cleaner fish, even when they are cleaning the inside of their mouths and one might think that it would be pretty tempting just to swallow one. Of course, cleaner fish do ‘cheat’ occasionally, taking a bite from the skin of a client, making the client jolt away and probably choose not to return to that particular cleaner again. © 2015 Scientific American
By James Gallagher Health editor, BBC News website Close your eyes and imagine walking along a sandy beach and then gazing over the horizon as the Sun rises. How clear is the image that springs to mind? Most people can readily conjure images inside their head - known as their mind's eye. But this year scientists have described a condition, aphantasia, in which some people are unable to visualise mental images. Niel Kenmuir, from Lancaster, has always had a blind mind's eye. He knew he was different even in childhood. "My stepfather, when I couldn't sleep, told me to count sheep, and he explained what he meant, I tried to do it and I couldn't," he says. "I couldn't see any sheep jumping over fences, there was nothing to count." Our memories are often tied up in images, think back to a wedding or first day at school. As a result, Niel admits, some aspects of his memory are "terrible", but he is very good at remembering facts. And, like others with aphantasia, he struggles to recognise faces. Yet he does not see aphantasia as a disability, but simply a different way of experiencing life. Take the aphantasia test It is impossible to see what someone else is picturing inside their head. Psychologists use the Vividness of Visual Imagery Questionnaire, which asks you to rate different mental images, to test the strength of the mind's eye. The University of Exeter has developed an abridged version that lets you see how your mind compares. © 2015 BBC.
Christopher Joyce Male treehoppers make their abdomens thrum like tuning forks to transmit very particular vibrating signals that travel down their legs and along leaf stems to other bugs — male and female. Male treehoppers make their abdomens thrum like tuning forks to transmit very particular vibrating signals that travel down their legs and along leaf stems to other bugs — male and female. Courtesy of Robert Oelman Animals, including humans, feel sound as well as hear it, and some of the most meaningful audio communication happens at frequencies that people can't hear. Elephants, for example, use these low-frequency rumbles to, among other things, find family or a mate across long distances. Whales do it, too. But you don't have to weigh a ton to rumble. In fact, you don't have to be bigger than a pea. Consider, for example, the treehopper, a curious little sap-sucking insect that lives on the stems of leaves. Or the tree cricket, which communicates by rubbing together tooth-like structures on its wings, the way you might draw your thumb across the teeth of a comb. University of Missouri biologist Rex Cocroft has spent much of his career listening closely to treehoppers. In 1999, a team from NPR's Radio Expeditions program rendezvoused with Cocroft at a locust tree in a backyard in Virginia. Soft-spoken and bespectacled, he was pressing a phonograph needle up against the stem of a leaf. © 2015 NPR