Chapter 6. Hearing, Balance, Taste, and Smell

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By VERONIQUE GREENWOOD When people tell you, “wake up and smell the roses,” they might be giving you bad advice. Your sense of smell may fluctuate in sensitivity over the course of 24 hours, in tune with our circadian clocks, with your nose best able to do its job during the hours before you go to sleep, according to a study published last month. The work, reported in the journal Chemical Senses, is part of a larger push to explore whether adolescents’ senses of taste and smell influence obesity. Rachel Herz, a sensory researcher at Brown University, and her colleagues designed this study to see if there might be times of day when the sense of smell was more powerful — perhaps making food smell particularly inviting. For the experiment, 37 adolescents ranging in age from 12 to 15 came into a lab for a very long sleepover party. For nine days, they followed a strict schedule to allow researchers to focus on the circadian clock, which helps control wake and sleep, but also influences other processes in the body, including metabolism. While more research is needed to test whether the results fully apply to adults, Dr. Herz says that as you grow up, the makeup of the smell receptors inside your nose doesn’t seem to change, although there is evidence your body clock may. The team kept track of where the teenagers were in their circadian cycle by measuring their saliva’s levels of melatonin, a hormone that rises and falls regularly over the course of the day. Every few hours, the children took a scent test, sniffing different concentrations of a chemical that smells like roses. The researchers recorded the lowest concentration they could detect at each time point. When the results were tallied up, the researchers saw a range of responses. “Nobody has the same nose,” Dr. Herz said. Some adolescents had only very mild changes in sensitivity, while sensitivity altered dramatically in others. Averaged together, however, the results showed that overall the circadian clock does affect smell, and that the times when the children’s noses were most sensitive tended to correspond to the evening, with an average peak of 9 p.m. © 2017 The New York Times Company

Keyword: Chemical Senses (Smell & Taste); Biological Rhythms
Link ID: 24311 - Posted: 11.09.2017

Rachael Lallensack It takes a village to teach a bat how to communicate. Baby Egyptian fruit bats learn calls from their mothers, but research now shows that they can learn new dialects, or the pitch of their vocalizations, from the colony members around them. Learning to communicate by repeating the noises that others make is something only a few mammal groups — including humans, whales and dolphins — are known to do. Researchers call this vocal learning, and it's something that they're starting to study in bats. Findings published on 31 October in PLOS Biology1 show that bats can also pick things up from the group around them, a process that the authors dub crowd vocal learning. Bats are becoming the best organism to use in studies of how mammals learn to vocalize, because they’re more easily manipulated in the lab than whales or dolphins. The latest research underscores their importance, says neuroscientist Michael Yartsev of the University of California, Berkeley, who was not involved with the work. Egyptian fruit bats (Rousettus aegyptiacus) are highly social and live in colonies with dozens to thousands of other bats. To see how the pups learn dialects, researchers caught 15 pregnant Egyptian fruit bats and took them into the lab. To control for potential genetic effects, they ensured that the mothers weren't closely related. The team then split the mothers into three groups of five and put each group into one of three chambers, where the mothers gave birth to their young. The scientists used recordings of wild Egyptian fruit bat colonies that were low in frequency, high or a mix of both frequencies, and then piped one pitch into each chamber. © 2017 Macmillan Publishers Limited,

Keyword: Animal Communication; Language
Link ID: 24275 - Posted: 11.01.2017

By Deirdre Sackett A few years ago, I watched a YouTube video called “Virtual Barbershop.” It was one of those viral videos that attempted to be somewhat educational. It featured (somewhat silly) barbershop sounds recorded with a special microphone that made the sounds appear as if in 3-D, to demonstrate how the brain localizes sounds. Although it was meant to be funny and a bit of a gag video, I noticed that some of the 3-D sounds actually relaxed me. In fact, I realized it was the same calming feeling I got when watching, of all things, Bob Ross’ “Joy of Painting” videos. Curious, I watched some of Bob’s YouTube videos, and sure enough, his soothing voice, brushing and tapping sounds, and calm, deliberate actions had me nearly falling asleep. By some happy little accident, I noticed a “recommended” video in the YouTube side bar called “Oh, such a good 3-D ASMR video.” I immediately felt relaxed upon hearing the sounds in the video, and even felt a small “tingle” in my head. That’s how I discovered that I had ASMR. ASMR? It sounds like some horrible affliction—an acronym for a weird, one-in-100 million condition. “Hi, I’m Deirdre, and I have ASMR.” What is it—and why is my brain tingling? © 2017 Scientific American,

Keyword: Hearing; Emotions
Link ID: 24244 - Posted: 10.26.2017

Nicola Davis When it comes to understanding how another person thinks and feels, it might be best to close your eyes and listen. A study by an American psychologist suggests that people are better able to pick up on the emotions of others when simply focusing on their voice, compared with both watching and listening to them, or just watching them. “Humans are actually remarkably good at using many of their senses for conveying emotions, but emotion research historically is focused almost exclusively on the facial expressions,” said Michael Kraus, a social psychologist at Yale University and author of the study. While combining information from a person’s voice with their facial expressions and other cues might at first seem like a way to boost understanding of their thoughts and feelings, Kraus says pooling the senses divides attention. What’s more, he notes, facial expressions can mask a person’s true feelings – something that he says is harder to do with the voice – while language plays a key role in how people understand and label their emotions. The upshot, he says, is that what people say, and the way they say it, offers the clearest insights into the emotions of others. “Listening matters,” said Kraus. “Actually considering what people are saying and the ways in which they say it can, I believe, lead to improved understanding of others at work or in your personal relationships.” © 2017 Guardian News and Media Limited

Keyword: Attention; Hearing
Link ID: 24173 - Posted: 10.11.2017

By Frank Swain Just what you need in the age of ubiquitous surveillance: the latest cochlear implants will allow users stream audio directly from their iPhone into their cochlear nerve. Apple and implant manufacturer Cochlear have made “Made for iPhone” connectivity available for any hearing implants that use the next-generation Nucleus 7 sound processor. The advance means that these implants can also stream music and Netflix shows. The technology was first unveiled in 2014 when it was added to hearing aids such as the Starkey Halo and ReSound LiNX. But this is the first time it’s been linked into the central nervous system. While some cochlear implants already offer Bluetooth connectivity, these often require users to wear extra dongles or other intermediary devices to pick up digital signals, and then rebroadcast them to the hearing aid as radio. This technology simply beams the signal right into the brain. It’s also a better way to use Bluetooth. Bluetooth headsets have been commonplace since the early 2000s, but the energy-sapping technology has meant they are typically clunky devices with poor battery life. In 2014, Apple technicians developed a way to stream audio over the low energy Bluetooth format used by wearables such as FitBits. Now, tiny devices like hearing aids – and Apple’s Airpods — can stream audio signals for up to a week on a battery the size of an aspirin. © Copyright New Scientist Ltd.

Keyword: Hearing
Link ID: 24163 - Posted: 10.09.2017

By NICHOLAS BAKALAR A poor sense of smell may indicate an increased risk for dementia, a new study has found. Researchers recruited 2,906 men and women ages 57 to 85, testing their ability to identify five odors — orange, leather, peppermint, rose and fish. Five years later, 4.1 percent of them had dementia. Of all the factors the researchers measured — age, sex, race, ethnicity, education, other diseases the subjects may have had — only cognitive ability at the start of the study and poorer performance on the “smell test” were associated with an increased risk for dementia. The study is in the Journal of the American Geriatrics Society. The risk went up steadily with the number of odors they failed to recognize, and over all, compared with those with no olfactory impairment, those with smelling difficulties had more than twice the likelihood of developing dementia. Even among those who initially tested within the normal range for mental ability, a poor sense of smell more than doubled the risk for dementia five years later. “This is not a simple, single-variable test for the risk of dementia,” said the lead author, Dr. Jayant M. Pinto, a specialist in sinus and nasal diseases at the University of Chicago. “But sensory function is an indicator of brain function. When sensory function declines, it can be a signal to have a more detailed examination to see if everything’s O.K.” © 2017 The New York Times Company

Keyword: Chemical Senses (Smell & Taste); Alzheimers
Link ID: 24137 - Posted: 10.03.2017

By Marlene Cimons In 2007, a few days after participating in a two-day sailing race, Cathy Helowicz began feeling dizzy. It was as if the floor and walls were moving. A decade later, “it’s never gone away,” she says. “Sometimes I wake up at 4 a.m. and feel like I’m in a washing machine.” Helowicz, 57, a former government computer scientist who lives in Jupiter, Fla., suffers from mal de débarquement syndrome (MdDS), a puzzling neurological disorder that leaves patients feeling as if they are rocking, swaying or bobbing when they are actually still. “I was very fortunate I didn’t have to go to a job, since you really cannot work with this,” she says of the little-understood disorder. (She left the government when she was 34 — before developing MdDS — and now writes children’s books and spy novels.) “I went through 11 doctors, 13 medications and seven months before I found a doctor who said I had classic MdDS symptoms.” Onset typically follows motion exposure — after a cruise, for example, or after flying, riding a train, even a lengthy car ride. MdDS can last for months, even years. It also can occur spontaneously, without motion exposure, although that is less common. “It’s an oscillating feeling like walking on a suspension bridge or a trampoline,” says Yoon-Hee Cha, an assistant professor at the Laureate Institute for Brain Research in Tulsa, who has been studying MdDS. “It can be an absolutely devastating disorder. What is difficult for people to understand is that patients can look normal but feel awful.” © 1996-2017 The Washington Post

Keyword: Miscellaneous
Link ID: 24134 - Posted: 10.02.2017

James Gorman Imagine a species that lived in a world of smells and didn’t pay a lot of attention to what things look like. What would members of that species use for a mirror? Would they even want a mirror? Yes, of course, we are talking about dogs, who usually don’t seem to understand the mirrors humans use. Sometimes they ignore them. Often they bark as if the dog in the mirror were a stranger. Scientists use mirrors to find out if animals recognize themselves, to see if they have some sense of self. Chimpanzees do very well on what is called the mirror test. A chimp will notice a mark on his face and perhaps even use the mirror to aid in removing it. He might use the mirror to examine parts of his body he can’t normally see, like the inside of his mouth. Researchers have reported that dolphins, one elephant and a magpie have also passed this test. Dogs have not, and that has raised questions about whether dogs might recognize themselves if another sense were tested. Alexandra Horowitz, a psychologist at Barnard College who studies the behavior of dogs and has written several books about them, decided to give dogs a chance at showing self-recognition on their own, smelly terms. In a recent study, she concludes that they do recognize the smell of their own urine. While some researchers find the study intriguing, the scientist who first developed that mirror mark test doesn’t think the evidence supports her conclusion. Still, even the idea of a smell mirror is mind (nose?) boggling. “I had always flirted with the idea in my head that there should be an olfactory mirror,” Dr. Horowitz said, acknowledging that “it could be horrifying for humans.” © 2017 The New York Times Company

Keyword: Chemical Senses (Smell & Taste); Consciousness
Link ID: 24095 - Posted: 09.22.2017

Amber Dance Ninad Kothari’s workplace looks like something out of a sci-fi film. The graduate student at Johns Hopkins University works in a darkened, red-lit room, where he trains bats to fly through obstacle courses. Shielding within the walls keeps radio and other human-made signals from interfering with transmissions from the tiny electrical signals he’s recording from the bats’ brains as the animals bob and weave. Layers of foam further insulate the cavelike lab against sound waves. An array of cameras and microphones complete the futuristic scene. The high-tech setup has its homemade touches, too: In one obstacle course, bats dodge dangling Quaker oatmeal cylinders. Kothari is part of a small cadre of neuroscientists who are getting the best sense yet of how bat brains work at a cellular level, thanks to modern technologies. Eavesdropping tools, which rely on tiny probes that track the activities of individual nerve cells, or neurons, are now miniaturized enough to outfit bats with head-mounted, wireless sensors. As the animals fly freely around the lab, the researchers can listen in on neurons. By allowing the bats to behave naturally, unencumbered by bulky equipment, scientists will discover exciting new facets of how bat brains work, says neuroscientist Nachum Ulanovsky of the Weizmann Institute of Science in Rehovot, Israel, who invented the new wireless sensors with colleagues. He and others, studying several different species of bats, are investigating how the flying mammals perceive their environment and navigate through it. |© Society for Science & the Public 2000 - 2017

Keyword: Hearing
Link ID: 24089 - Posted: 09.21.2017

Patrick Barkham Humans trying to chat each other up in a noisy nightclub may find verbal communication futile. But it appears even more pointless for pumpkin toadlets after scientists discovered that females have lost the ability to hear the sound of male mating calls. An international team from Brazil, Denmark and the UK has discovered that the males of two species of tiny orange frogs continue to make high-pitched calls despite neither females nor males being able to hear them. It is believed to be the first case in the animal kingdom of a communication signal enduring even after its target audience has lost the ability to detect it. Field studies began in Brazil’s Atlantic forest by playing frog calls to determine how these species, which possess a middle ear, could hear their own calls. Lead researcher Dr Sandra Goutte at the Universidade Estadual de Campinas, São Paulo, was surprised to find the frogs refused to respond to her playback communication, didn’t change their calling behaviour and didn’t even orient themselves towards the sounds. “I thought I would find the sound transmission pathway from the outside to the middle ear,” she said. “We didn’t think it would be possible that they would not be able to hear their own calls.” © 2017 Guardian News and Media Limited

Keyword: Hearing; Sexual Behavior
Link ID: 24088 - Posted: 09.21.2017

by Helen Thompson Barn owl ears age well. Unlike other animals, the birds don’t suffer from hearing loss as a hallmark of aging, a new study suggests. Beyond people, age-related hearing loss has been documented in mice, gerbils and chinchillas. Those deficits are linked to deterioration of the tiny hair cells that line the sensory layer of the eardrum. But some evidence hints that birds may not suffer from dips in hearing. Bianca Krumm and her colleagues at the University of Oldenburg in Germany tested the ear sensitivity of seven barn owls (Tyto alba) grouped by age. There weren’t significant differences in what 2-year-old owls could hear versus those age 13 or older, suggesting the birds’ ears remain intact despite age, the researchers conclude September 20 in Proceedings of the Royal Society B. While the exact mechanism for this apparent ear agelessness remains elusive, the researchers suspect that the birds must continuously regenerate sensory ear tissue — a process that wanes with age in other species. © Society for Science & the Public 2000 - 2017

Keyword: Hearing; Regeneration
Link ID: 24078 - Posted: 09.20.2017

Bruno Martin “I heard a thud behind me,” says zoologist Stefan Greif, recalling the first time he noticed a bat crash into a metal plate propped up against a wall in his lab’s flight chamber. Now, in a study published on 7 September in Science1, a team led by Greif — of the Max Planck Institute for Ornithology in Seewiesen, Germany — explains why bats often slam into vertical panes, such as glass windows.These smooth surfaces interfere with bats’ echolocation by reflecting sound away from the creatures. Bats rely on echolocation to navigate in the dark. They locate and identify objects by sending out shrill calls and listening to the echoes that bounce back. Greif and his colleagues tested the echolocation of 21 wild-caught greater mouse-eared bats (Myotis myotis) in the lab. The researchers placed a featureless metal plate on a side wall at the end of a flight tunnel. The bats interpreted the smooth surface — but not the adjacent, felt-covered walls — as a clear flight path. Over an an average of around 20 trials for each bat, 19 of them crashed into the panel at least once. The researchers also put up smooth, vertical plates near wild bat colonies, and saw similar results. The animals became confused owing to a property of smooth surfaces called ‘acoustic mirroring’. Whereas rough objects bounce some echoes back towards the bat, says Greif, a smooth surface reflects all echolocation calls away from the source. This makes a smooth wall appear as empty space to the bats, until they are directly in front of it. Only once a bat is facing the surface are their perpendicular echoes reflected back, which alerts the bat to its mistake. This explains why some bats attempted to swerve out of harm’s way at the last second — but often too late. © 2017 Macmillan Publishers Limited

Keyword: Hearing
Link ID: 24048 - Posted: 09.08.2017

By SANDY SMOLAN I’ve long been interested in the capacity of storytelling and journalism to transport an audience. Shooting my first documentary in North Africa 35 years ago, I used multiple projectors and screens to create an immersive experience. The approach at the time was experimental and while I moved on to more traditional storytelling in features, television and documentaries, I always held on to the idea of using immersive environments to transport viewers and allow them to experience an expanded vision of the world. They surrounded the divers and started clicking — they seemed to be saying hello. Then last year I visited the virtual reality lab at Stanford, which is at the fore of contemporary immersive journalism. I realized that V.R. had the potential to become a powerful new form of storytelling, and the medium has been evolving faster than anyone had ever expected. After I read James Nestor’s book “Deep,” about free diving and the human connection to the ocean, I realized that the combination of stunning imagery and the way in which a team of researchers were studying the language of whales and dolphins by free diving with them would translate perfectly to V.R. I had never forgotten my first open water dive in the Caribbean with my father when I was 17 and the transcendent experience of being suspended 30 feet beneath the surface, midway between the boat above us and the white sand of the ocean floor below. Now my son has become a free diver and as I recently watched him dive silently, on a single breath, his body elongated with outsize fins, unencumbered by tanks, regulators and the noise of escaping bubbles, I saw what James so eloquently described in his book — a human being interacting with the ocean and marine life in a manner few people can ever experience. © 2017 The New York Times Company

Keyword: Animal Communication; Hearing
Link ID: 24032 - Posted: 09.04.2017

By Clare Wilson Some people who are blind can echolocate like bats, making clicks with their mouths that help them understand the environment around them. Now researchers are beginning to understand how this works, so non-sighted people may one day be able to learn the technique. While many people who are blind get information from ambient echoes, only a few make noises themselves to echolocate. Some, such as Daniel Kish (pictured), are so proficient they can draw a sketch of a room after clicking their way around it, or even go mountain biking along unfamiliar routes. Daniel Kish: Blind children should be allowed to echolocate like me Previous research revealed that this human echolocation involves some brain areas that are used for vision in sighted people. Kish, who was blind almost from birth, thinks he experiences the sensations as something akin to images. “It’s not computational. There’s a real palpable experience of the image as a spatial representation – here are walls, here are the corners, here is the presence of objects.” In the latest study, Lore Thaler of Durham University, UK, and her team carried out the first in-depth acoustic analysis of the mouth clicks. They worked with Kish and two other blind echolocators from the Netherlands and Austria. © Copyright New Scientist Ltd.

Keyword: Hearing
Link ID: 24021 - Posted: 09.01.2017

By Helen Briggs BBC News They migrate thousands of kilometres across the sea without getting lost. The Arctic tern, for instance, spends summer in the UK, then flies to the Antarctic for the winter. Yet, scientists are still unsure exactly how birds perform such extreme feats of migration, arriving in the right place every year. According to new research, smell plays a key role when birds are navigating long distances over the ocean. Researchers from the universities of Oxford, Barcelona and Pisa temporarily removed seabirds' sense of smell before tracking their movements. They found the birds could navigate normally over land, but appeared to lose their bearings over the sea. This suggests that they use a map of smells to find their way when there are no visual cues. Previous experiments had suggested that removing birds' sense of smell impairs homing ability. However, some had questioned whether sensory deprivation might impair some other function, such as the ability to search for food. ''Our new study eliminates these objections, meaning it will be very difficult in future to argue that olfaction is not involved in long-distance oceanic navigation in birds,'' said study researcher Oliver Padget of Oxford University's Department of Zoology. The researchers studied 30 Scopoli's shearwaters living off the coast of Menorca. The birds nest in the Mediterranean, but spend the non-breeding season in the Atlantic, including areas off the west coast of Africa and the east coast of Brazil. Some of the birds were made to temporarily lose their sense of smell through nasal irrigation with zinc sulphate; another group carried small magnets; and a third group acted as a control. © 2017 BBC.

Keyword: Animal Migration; Chemical Senses (Smell & Taste)
Link ID: 24010 - Posted: 08.30.2017

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

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

By Bianca Datta Hallucinations are often distressing—a suggestion that something is amiss in our brains. But new research suggests we’re all susceptible to hallucinations, and that may not be such a bad thing. In a paper released last week in Science, a team from Yale University set out to understand how we interpret the world around us—in short, how we determine what’s real and what’s not. They suspected that people who regularly hallucinate perceive the world based on what they expect to happen, while others, who don’t hallucinate, would rely more what their senses are telling them is happening in the world. Even healthy participants experienced conditioned hallucinations. The mechanism that causes auditory hallucinations is related to those used in normal perception. To determine that, authors Phil Corlett and Al Powers began by conditioning participants to hear a tone when they were shown a checkerboard pattern. Then they slowly removed the actual sound and asked people when they heard it. Participants who regularly heard voices were five times more likely to say they heard a tone when there wasn’t one, and they were 25-30% more confident in their choice. But they weren’t alone in hearing things. In fact, all of the participants experienced some induced hallucinations during the experiment. “I did not expect that people who did not have a psychotic illness would perform so similarly to people who did hear voices,” Powers says. “They were very, very alike.” © 1996-2017 WGBH Educational Foundation

Keyword: Schizophrenia; Hearing
Link ID: 23981 - Posted: 08.22.2017

By Jenna Gallegos Pathogens are real jerks. As if infecting and killing plants and animals isn’t bad enough, they can also turn their hosts into zombies that spread the pathogens to their next victim. Now scientists report that bacteria make some victims summon other victims as their dying act. The bacteria hijack the chemical signaling pathway of insects, making them release a burst of hormones that serve as a beacon to attract friends and potential mates right before the bacteria kill off the host. Like malware marauding as an enticing link, the bacteria attract and then infect. Fruit flies are generally pretty good at avoiding hazards. They can detect when food is infected with a dangerous mold or when a parasitic wasp is nearby, said Markus Knaden, a researcher at the Max Planck Institute for Chemical Ecology in Jena, Germany, who was involved in the study. In both cases, the flies won’t lay their eggs near the infectious agent. That’s why Knaden and colleagues at Cornell University were so surprised when they found that flies were actually attracted to other insects with a certain bacterial infection. “If you’re sitting in a theater and someone next to you is coughing, you move to another chair,” said Bill Hansson, one of the Max Planck authors of the study, published Wednesday in the journal Nature Communications. They expected flies to behave the same way, but instead, healthy flies found their sick friends to be extremely attractive. © 1996-2017 The Washington Post

Keyword: Sexual Behavior; Chemical Senses (Smell & Taste)
Link ID: 23964 - Posted: 08.16.2017

Allison Aubrey What we eat can influence more than our waistlines. It turns out, our diets also help determine what we smell like. A recent study found that women preferred the body odor of men who ate a lot of fruits and vegetables, whereas men who ate a lot of refined carbohydrates (think bread, pasta) gave off a smell that was less appealing. Skeptical? At first, I was, too. I thought this line of inquiry must have been dreamed up by the produce industry. (Makes a good marketing campaign, right?) But it's legit. "We've known for a while that odor is an important component of attractiveness, especially for women," says Ian Stephen of Macquarie University in Australia. He studies evolution, genetics and psychology and is an author of the study. From an evolutionary perspective, scientists say our sweat can help signal our health status and could possibly play a role in helping to attract a mate. How did scientists evaluate the link between diet and the attractiveness of body odor? They began by recruiting a bunch of healthy, young men. They assessed the men's skin using an instrument called a spectrophotometer. When people eat a lot of colorful veggies, their skin takes on the hue of carotenoids, the plant pigments that are responsible for bright red, yellow and orange foods. "The carotenoids get deposited in our skin," explains Stephen. © 2017 npr

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 23961 - Posted: 08.15.2017