By Emma Tracey BBC News, Ouch An online magazine for the deaf community, Limping Chicken, recently ran an item on how deaf and hearing people sneeze differently. The article by partially deaf journalist Charlie Swinbourne got readers talking - and the cogs started turning at Ouch too. Swinbourne observes that deaf people don't make the "achoo!" sound when they sneeze, while hearing people seem to do it all the time - in fact, he put it in his humorous list, The Top 10 Annoying Habits of Hearing People. Nor is "achoo" universal - it's what English-speaking sneezers say. The French sneeze "atchoum". In Japan, it's "hakashun" and in the Philippines, they say "ha-ching". Inserting words into sneezes - and our responses such as "bless you" - are cultural habits we pick up along the way. So it's not surprising that British deaf people, particularly users of sign language, don't think to add the English word "achoo" to this most natural of actions. For deaf people, "a sneeze is what it should be... something that just happens", says Swinbourne in his article. He even attempts to describe what an achoo-free deaf sneeze sounds like: "[There is] a heavy breath as the deep pre-sneeze breath is taken, then a sharper, faster sound of air being released." Very little deaf-sneeze research exists, but a study has been done on deaf people and their laughter. BBC © 2013

Keyword: Hearing
Link ID: 18355 - Posted: 07.08.2013

Melatonin is marketed as a natural sleep aid but it's potentially risky for healthy children to use long term, Canadian pediatricians say. Difficulties settling, falling asleep and staying asleep affect up to 25 per cent of children generally and up to half of those with physical and mental health problems, according to the Canadian Sleep Society. Melatonin is a hormone of darkness that is part of the sleep cycle. People can buy melatonin supplements at pharmacies and health food stores to overcome jet lag or occasional insomnia. But long-term use by healthy, developing children isn't advised, said Dr. Shelly Weiss, a neurologist at the Hospital for Sick Children in Toronto, who is studying the use of melatonin supplements for improving sleep in children with epilepsy. "It's being touted as this magic pill," said Weiss. "There's definitely concern that people are going to use it more widely and not appreciate that their child can learn to sleep better without a hormone being given." Melatonin supplements contain between 25 to 50 times as much melatonin as the body makes at night, Weiss noted. "There's definitely potential risk, mostly to delayed puberty or delayed development in children who have taken it for a long time," said Weiss, who is also president of the Canadian Sleep Society and an associate professor at the University of Toronto. © CBC 2013

Keyword: Sleep; Hormones & Behavior
Link ID: 18354 - Posted: 07.08.2013

By Jessica Wright and SFARI.org With the right incentive, such as winning a prize, children with autism do fairly well at inferring the thoughts and beliefs of others, according to a study published in the May issue of Developmental Science. Research has shown that children with autism usually struggle with a widely used test designed to gauge this ability, called theory of mind. The new study suggests that they are able to grasp theory of mind, but don’t have a strong motivation to give the correct answer when taking the classic test. The particulars of the test vary, but children are generally told a story in which two characters (often called Sally and Ann) place an object in a basket. After Sally leaves the room, Ann moves the item into a box. The child passes the test if he or she knows that Sally will look for the item in the basket and not the box. Typical children struggle with this test as 3-year-olds, but most pass it by 5 years of age. The majority of children with autism continue to fail the test well into their teenage years. Adults with autism are usually able to pass the Sally-Ann test, as it is often called, but struggle with more subtle examples of theory of mind. In the new study, the researchers revised the Sally-Ann test into a game. For typically developing children, the motivation to answer a question correctly may be tied to a desire for social interactions. In contrast, children with autism may use theory of mind when they want something concrete, for example when competing for things with a sibling, the researchers say. © 2013 Scientific American,

Keyword: Autism; Learning & Memory
Link ID: 18353 - Posted: 07.06.2013

by Sara Reardon As a baby's brain rewires itself to face the world ahead, its DNA is rewiring itself at the same time. New maps of chemical modifications to brain DNA have revealed massive epigenetic changes during the first few years of life. Environmental stressors that disrupt the process during this crucial period could lead to mental disorders. During development in mammals, chemical tags called methyl groups are added to certain cytosine nucleotides in the DNA, which affects how nearby genes are expressed. Later, environmental stressors such as stress, diet and disease can alter these patterns and change the genes' expression. These epigenetic modifications appear to play a role in some neurological disorders. For instance, one recent study found that in genetically identical twin pairs in which only one twin has autism, genes involved in brain development have different epigenetic patterns. Because epigenetic patterns can differ between tissues in the body, Ryan Lister of the University of Western Australia in Crawley and colleagues decided to zero in on the brain's methylation. They collected nine human brains including examples from fetuses, two-month-old babies, toddlers, teenagers and older adults, and the same from mice at equivalent stages of development. © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Neurogenesis
Link ID: 18352 - Posted: 07.06.2013

Oxytocin, the naturally occuring human hormone linked to bonding with a newborn and romantic partner, could also help improve mood after rejection, a laboratory study suggests. When scientists in Montreal gave 100 students either oxytocin or a placebo through a nose spray and then tried to snub them in a conversation, feelings of trust were higher in the hormone group. But the hormone had no effect among those who weren't emotionally charged up by the social rejection of having researchers posing as students disagree, interrupt or ignore them. "Instead of the traditional 'fight or flight' response to social conflict where people get revved up to respond to a challenge or run away from it, oxytocin may promote the 'tend and befriend' response where people reach out to others for support after a stressful event. That can, in turn, strengthen social bonds and may be a healthier way to cope," study author Mark Ellenbogen said in a release. For a decade, researchers have speculated that oxytocin, known as the love hormone, motivates people to seek out social support to respond to challenges and blunt the negative hit of stress. Ellenbogen's team said its study offers the first experimental support of the idea that oxytocin motivates us to strengthen social bonds during times of distress. © CBC 2013

Keyword: Hormones & Behavior; Pain & Touch
Link ID: 18351 - Posted: 07.06.2013

by Helen Thomson "I told my daughter her living room TV was out of sync. Then I noticed the kitchen telly was also dubbed badly. Suddenly I noticed that her voice was out of sync too. It wasn't the TV, it was me." Ever watched an old movie, only for the sound to go out of sync with the action? Now imagine every voice you hear sounds similarly off-kilter – even your own. That's the world PH lives in. Soon after surgery for a heart problem, he began to notice that something wasn't quite right. "I was staying with my daughter and they like to have the television on in their house. I turned to my daughter and said 'you ought to get a decent telly, one where the sound and programme are synchronised'. I gave a little chuckle. But they said 'there's nothing wrong with the TV'." Puzzled, he went to the kitchen to make a cup of tea. "They've got another telly up on the wall and it was the same. I went into the lounge and I said to her 'hey you've got two TVs that need sorting!'." That was when he started to notice that his daughter's speech was out of time with her lip movements too. "It wasn't the TV, it was me. It was happening in real life." PH is the first confirmed case of someone who hears people speak before registering the movement of their lips. His situation is giving unique insights into how our brains unify what we hear and see. It's unclear why PH's problem started when it did – but it may have had something to do with having acute pericarditis, inflammation of the sac around the heart, or the surgery he had to treat it. © Copyright Reed Business Information Ltd

Keyword: Attention; Language
Link ID: 18350 - Posted: 07.06.2013

Gregory Gage is being honored as a Champion of Change for his dedication to increasing public engagement in science and science literacy. Science has a rich history of everyday citizens assisting in great discoveries, and I am honored that our work to encourage amateur neuroscience has been selected by The White House for the Citizen Science Champion of Change award. We know a lot about how our amazing brain works, but there is much, much more that remains to be discovered. In fact, we have no cures and only insufficient treatments for neurological disorder, even though about 1 out of every 5 people will be diagnosed with a brain disease. Change is indeed needed in our nation’s approach to science education to bring more focus on neuroscience. I am a “DIY” neuroscientist. I co-founded a low-fi company called Backyard Brains with my grad-school labmate, Tim Marzullo. While working on our Ph.D., we would often go out to local public schools to talk about the importance of studying neuroscience. We developed our lesson plans using models and analogies about how the brain works, but what we really wanted to teach the students was “electrophysiology”... as this is truly is how the brain works. The brain is an electrical organ, and the cells (neurons) communicate with “spikes”: a brief pulse of electricity. In my research at the university, I would record these spikes to learn what the neurons were telling us about how the brain worked. Traditionally, to do experiments with electrophysiology, one needs to be in a Ph.D. program and use expensive equipment (our electrophysiology rig cost $40,000). To make this accessible for our outreach goals, Tim and I set out on a self-imposed engineering challenge: to reduce this equipment down to the basic components, and record a spike for <$100. Less than a year later, we got our first prototype to work and were able to bring spikes into the classrooms! After getting requests from colleagues and teachers, we launched Backyard Brains. We are now a growing education company with neuroscience gear in over 45 countries on all 7 continents!

Keyword: Miscellaneous
Link ID: 18349 - Posted: 07.06.2013

Ransom Stephens - The video linked here shows how a team of UC Berkeley researchers (two neuroscientists, a bioengineer, two statisticians, and a psychologist) decoded images from brain scans of test subjects watching videos. Yes, by analyzing the scans, they reproduced the videos that the subjects watched. While the reproduced videos are hazy, the ability to reproduce images from the very thoughts of individuals is striking. Here’s how it works: fMRI (functional magnetic resonance imaging) scans light up pixels in three dimensions, 2 mm cubes called voxels. You’ve seen the images, color maps of the brain. The colors represent the volume of blood flow in each voxel. Since an fMRI scan takes about a second to record, the voxel colors represent the time-average blood flow during a given second. Three different subjects (each of whom were also authors of the paper) watched YouTube videos from within an fMRI scanner. Brain scans were taken as rapidly as possible as they watched a large number of 12 minute videos. Each video was watched one time. The resulting scans were used to “train” models. The models consisted of fits to the 3D scans and unique models were developed for each person. By fitting a subject’s model to the time-ordered series of scans and then optimizing the model over a large sample of known videos, the model translates between measured blood flow and features in the video like shapes, edges, and motion. © 2013 UBM Tech,

Keyword: Vision; Brain imaging
Link ID: 18348 - Posted: 07.04.2013

By Helen Briggs BBC News Keeping mentally active by reading books or writing letters helps protect the brain in old age, a study suggests. A lifetime of mental challenges leads to slower cognitive decline after factoring out dementia's impact on the brain, US researchers say. The study, published in Neurology, adds weight to the idea that dementia onset can be delayed by lifestyle factors. An Alzheimer's charity said the best way to lower dementia risk was to eat a balanced diet, exercise and stay slim. In a US study, 294 people over the age of 55 were given tests that measured memory and thinking, every year for about six years until their deaths. They also answered a questionnaire about whether they read books, wrote letters and took part in other activities linked to mental stimulation during childhood, adolescence, middle age, and in later life. After death, their brains were examined for evidence of the physical signs of dementia, such as brain lesions and plaques. The study found that after factoring out the impact of those signs, those who had a record of keeping the brain busy had a rate of cognitive decline estimated at 15% slower than those who did not. Dr Robert Wilson, of Rush University Medical Center in Chicago, who led the study, said the research suggested exercising the brain across a lifetime was important for brain health in old age. BBC © 2013

Keyword: Alzheimers; Learning & Memory
Link ID: 18347 - Posted: 07.04.2013

It only takes one bad apple to spoil the bunch, and the same may be true of certain proteins in the brain. Studies have suggested that just one rogue protein (in this case, a protein that is misfolded or shaped the wrong way) can act as a seed, leading to the misfolding of nearby proteins. According to an NIH-funded study, various forms of these seeds — originating from the same protein — may lead to different patterns of misfolding that result in neurological disorders with unique sets of symptoms. “This study has important implications for Parkinson’s disease and other neurodegenerative disorders,” said National Institute of Neurological Disorders and Stroke (NINDS) Director Story Landis, Ph.D. “We know that among patients with Parkinson’s disease, there are variations in the way that the disorder affects the brains. This exciting new research provides a potential explanation for why those differences occur.” An example of such a protein is alpha-synuclein, which can accumulate in brain cells, causing synucleinopathies, multiple system atrophy, Parkinson’s disease, Parkinson’s disease with dementia (PDD), and dementia with Lewy bodies (DLB). In addition, misfolded proteins other than alpha-synuclein sometimes aggregate, or accumulate, in the same brains. For example, tau protein collects into aggregates called tangles, which are the hallmark of Alzheimer’s disease and are often found in PDD and DLB brains. Findings from this study raise the possibility that different structural shapes, or strains, of alpha-synuclein may contribute to the co-occurrence of synuclein and tau accumulations in PDD or DLB.

Keyword: Parkinsons; Alzheimers
Link ID: 18346 - Posted: 07.04.2013

A UC Berkeley study suggests that sleep deprivation triggers anxiety by inducing hyperactivity in brain regions that control emotions. The study, published in the Journal of Neuroscience, suggests that sleep therapy can help patients with anxiety disorders. Stress and anticipation bring anxiety that can sometimes be good; if under control, anxiety might help a person focus and be more efficient. But a patient with anxiety disorders, such as post-traumatic stress disorder (PTSD), generalized anxiety disorder (GAD), obsessive-compulsive disorder (OCD) or other disorders and phobias, cannot control it. The feeling of anxiety and nervousness is constant and has major negative impact on their everyday life. The socioeconomic impact is huge as about one in five adults in the U.S. are affected by such mental illnesses. What are the drivers of anxiety disorders? Why can some people control anxiety while others cannot? Research studies have shown over the years that causes can be genetics, personality, social environment and brain chemistry. Scientists have found a network of neurons in the brain that supports affective anticipation and anxiety. More precisely, those with anxiety disorders have hyperactivity in certain regions of the brain that process emotions, including the amygdala and anterior insula cortex. On top of that, sleep deprivation amplifies the symptoms, a setback for patients because it is very common for them to suffer from sleep abnormalities. Looking for more clues about the connection between sleep and anxiety management, Matthew P. Walker, professor of psychology and neuroscience at UC Berkeley, led a study that looked for differences in the activity of the amygdala and anterior insula cortex in the brains of healthy adults after sleep deprivation and after a good night’s sleep.

Keyword: Sleep; Emotions
Link ID: 18345 - Posted: 07.04.2013

By GRETCHEN REYNOLDS In an eye-opening demonstration of nature’s ingenuity, researchers at Princeton University recently discovered that exercise creates vibrant new brain cells — and then shuts them down when they shouldn’t be in action. For some time, scientists studying exercise have been puzzled by physical activity’s two seemingly incompatible effects on the brain. On the one hand, exercise is known to prompt the creation of new and very excitable brain cells. At the same time, exercise can induce an overall pattern of calm in certain parts of the brain. Most of us probably don’t realize that neurons are born with certain predispositions. Some, often the younger ones, are by nature easily excited. They fire with almost any provocation, which is laudable if you wish to speed thinking and memory formation. But that feature is less desirable during times of everyday stress. If a stressor does not involve a life-or-death decision and require immediate physical action, then having lots of excitable neurons firing all at once can be counterproductive, inducing anxiety. Studies in animals have shown that physical exercise creates excitable neurons in abundance, especially in the hippocampus, a portion of the brain known to be involved in thinking and emotional responses. But exercise also has been found to reduce anxiety in both people and animals. How can an activity simultaneously create ideal neurological conditions for anxiety and leave practitioners with a deep-rooted calm, the Princeton researchers wondered? So they gathered adult mice, injected them with a substance that marks newborn cells in the brain, and for six weeks, allowed half of them to run at will on little wheels, while the others sat quietly in their cages. Copyright 2013 The New York Times Company

Keyword: Neurogenesis; Emotions
Link ID: 18344 - Posted: 07.03.2013

by Helen Fields When a bat moves in for the kill, some moths jiggle their genitals. Researchers made the observation by studying three species of hawk moths—big moths that can hover—in Malaysia. They snared the insects with bright lights, tied tiny leashes around their waists, and let them fly while bat attack sounds played. All three species responded to the noises with ultrasound—which they made by shaking their private parts, the team reports online today in Biology Letters. Males have a structure they use for hanging onto females when they mate; to make the sound, they scrape a patch of large scales on the structure against the very end of their abdomen , letting out two bursts of rapid clicks. Females also make a sound, but the researchers aren't sure how. The scientists don't know exactly what the sounds are for, either. The noise may warn the bats that they're trying to mess with a fast-moving, hard-to-catch piece of prey, or it might jam the bat's ultrasound signals. Either way, the racy display may save their lives. © 2010 American Association for the Advancement of Science

Keyword: Hearing; Sexual Behavior
Link ID: 18343 - Posted: 07.03.2013

By SABRINA TAVERNISE PORTSMOUTH, Ohio — Prescription pain pill addiction was originally seen as a man’s problem, a national epidemic that began among workers doing backbreaking labor in the coal mines and factories of Appalachia. But a new analysis of federal data has found that deaths in recent years have been rising far faster among women, quintupling since 1999. More women now die of overdoses from pain pills like OxyContin than from cervical cancer or homicide. And though more men are dying, women are catching up, according to the analysis by the Centers for Disease Control and Prevention. And the problem is hitting white women harder than black women, and older women harder than younger ones. In this Ohio River town on the edge of Appalachia, women blamed the changing nature of American society. The rise of the single-parent household has thrust immense responsibility on women, who are not only mothers, but also, in many cases, primary breadwinners. Some who described feeling overwhelmed by their responsibilities said they craved the numbness that drugs bring. Others said highs made them feel pretty, strong and productive, a welcome respite from the chaos of their lives. “I thought I was supermom,” said Crystal D. Steele, 42, a recovering addict who said she began to take medicine for back pain she developed working at Kentucky Fried Chicken. “I took one kid to football, the other to baseball. I went to work. I washed the car. I cleaned the house. I didn’t even know I had a problem.” © 2013 The New York Times Company

Keyword: Drug Abuse; Pain & Touch
Link ID: 18342 - Posted: 07.03.2013

Should I stay or should I go? Well, how much food do you have? In some organisms, sexual desire is expressed by leaving, that is, by bidding adieu to a delicious pile of food and wandering off in search of a mate. But not just any mate, a mate with food! Lipton et al., at Albert Einstein College of Medicine, use the “leaving assay” to measure male sexual desire. Their subject is the elegant, rod-like worm, Caenorhabditis elegans.* They start by placing males on their preferred food source; then they measure how often males exit in search of mating partners. You can see the trails they leave in the substrate in this video of C. elegans appropriating Harlem art and culture. How do the researchers know “leaving” is a sex behavior? Context. Leaving a food source occurs only in a sexual context, and the leaving assay is being used to tease apart the threads that control the appetites for food and sex. First, a quick lesson in the fascinating sexuality of C. elegans. Males are not interested in other males, but they search intensely for a mating partner of the other sex. Note that I said “other sex” not “opposite sex.” There are no female C. elegans. Males of this species mate enthusiastically with hermaphrodites. Hermaphrodites can, of course, self-fertilize, but sexual unions between males and hermaphrodites are far more fruitful than selfing. For hermaphrodites, mating with a male will produce more offspring, and for males, hermaphrodites are the only crying game in town.

Keyword: Sexual Behavior
Link ID: 18341 - Posted: 07.03.2013

by Mark Viney The largest and most comprehensive study yet into the long-term health of children born as a result of IVF confirms that they are no more likely to develop autism than children conceived naturally. Some IVF procedures can, however, lead to a small but significant increased risk of intellectual disability. Making babies isn't what it once was. Around 1 in 50 children are now conceived through IVF, and 5 million "test tube babies" have been born worldwide since 1978. The growing numbers of IVF births has prompted some to question whether the procedure leads to any health problems. For example, the IVF embryo transfer procedure is more likely to lead to twin births, which can lead to health problems in babies. Others wonder whether children born through IVF procedures are at a greater risk of developing autism. The evidence to date has been ambiguous. In an effort to resolve the question, a research team including Karl-Gösta Nygren at the Karolinska Institute in Stockholm, Sweden, looked at the health of 2.5 million children born in Sweden between 1982 and 2007, following them for an average of 10 years. Of these children, about 31,000 were born following an IVF procedure. Some 19,500 of these IVF births followed simple mixing of sperm and egg in a dish, but in 10,500 cases, the sperm were unable to penetrate and fertilise the egg under their own steam, and were instead artificially injected into the egg. For the remaining cases – fewer than 1000 in total – there were no sperm in the prospective fathers' ejaculate, so the sperm were extracted from their testicles through a surgical procedure before being injected into the egg. © Copyright Reed Business Information Ltd.

Keyword: Autism
Link ID: 18340 - Posted: 07.03.2013

by Emily Underwood Pay attention! Whether it's listening to a teacher giving instructions or completing a word problem, the ability to tune out distractions and focus on a task is key to academic success. Now, a new study suggests that a brief training program in attention for 3- to 5-year-olds and their families could help boost brain activity and narrow the academic achievement gap between low- and high-income students. Children from families of low socioeconomic status generally score lower than more affluent kids on standardized tests of intelligence, language, spatial reasoning, and math, says Priti Shah, a cognitive neuroscientist at the University of Wisconsin who was not involved in the study. "That's just a plain fact." A more controversial question that scientists and politicians have batted around for decades, says Shah, is "What is the source of that difference?" Part of it may be genetic, but environmental factors, ranging from prenatal nutrition to exposure to toxic substances like lead, may also account for the early childhood differences in cognitive ability that appear by age 3 or 4. So far, however, "there aren't that many randomized, controlled trials that show that the environment has an impact on a child's abilities," Shah says. The new study does just that. It focuses on the ability to hone in on a task and ignore distractions, which "leverages every single thing we do," says cognitive neuroscientist Helen Neville at the University of Oregon, Eugene. For more than 30 years, Neville and her colleagues have been studying the neural bases of this ability, called selective attention. © 2010 American Association for the Advancement of Science

Keyword: Attention; Development of the Brain
Link ID: 18339 - Posted: 07.03.2013

By Christie Aschwanden, It’s a thought that crosses many middle-aged minds when a word is forgotten or a set of keys misplaced: Is this a fluke, or the first sign of dementia? “Most of us will experience some cognitive changes with age,” says Molly Wagster, chief of the behavioral and systems neuroscience branch of the National Institute on Aging, who likens the mental change to the slowing of a marathon runner’s times with advancing years. The ability to call up words is one of the first things to slip. “You might find it more difficult to recall someone’s name or the name of a book you read or favorite movie. Eventually, you’ll remember it, but it takes a little longer,” Wagster says. Such problems are irritating and frustrating, but they’re usually not a sign that your mind is going, Wagster says. “There are a lot of things that have some evidence behind them, but it’s hard to find interventions that have convincing evidence behind them,” says Victor Henderson, a neurologist who studies cognitive aging at Stanford University Medical School. Physical activity seems like the most promising thing you can do to keep your brain at its best, Henderson says. The evidence comes mostly from observational studies rather than the randomized, controlled trials that are considered the gold standard, but it’s consistent: People who engage in aerobic activity — for instance, walking several times per week — show improvements in their cognitive function, particularly in their ability to switch quickly from task to task, Wagster says. © 1996-2013 The Washington Post

Keyword: Learning & Memory; Alzheimers
Link ID: 18338 - Posted: 07.03.2013

By RONI CARYN RABIN Martha Rhodes experienced her first bout of depression at 13. By her late 50s, she had taken just about every antidepressant there is, including Zoloft, Lexapro and Paxil — which did the trick for many years, but had side effects — then Effexor, Lamictal, Seroquel and Abilify. After a suicide attempt in 2009, she tried something radically different: transcranial magnetic stimulation, or TMS, a treatment in which magnetic pulses are used to stimulate parts of the brain believed to be involved in mood regulation. Unlike electroconvulsive or shock therapy, which is also used to treat stubborn depression, TMS does not generally produce seizures. Every day, she spent just over half an hour in a chair with a powerful magnet affixed to the front left side of her head. After four weeks, “I woke up and something was different,” said Mrs. Rhodes, who wrote a book, “3,000 Pulses Later” describing the treatment. “I felt lighter. I didn’t wake up in the morning and wish I were dead.” For Mrs. Rhodes, 63, a former advertising executive in Danbury, Conn., TMS treatment was transformative, and she no longer needs antidepressants. But there are still many questions about just how many severely depressed patients respond to TMS, which requires daily office visits for several weeks, costs thousands of dollars and is often not covered by insurance. For the therapy, patients sit in a doctor’s office with a large magnet pressed to the left side of their heads. The idea is that a pulsed magnetic field, similar to that used in M.R.I.’s, creates an electrical current in the surface of the brain that “resets” the patient’s mood regulatory system. Copyright 2013 The New York Times Company

Keyword: Depression
Link ID: 18337 - Posted: 07.02.2013

By Scicurious Sometimes, funny stories really bring out the wonder of the human body. You can get orgasms triggered in your feet, because of overlap in the sensory cortex. Receptors that are involved in narcolepsy are also involved in how much you eat. And knocking out receptors that regulate taste…can make you sterile? Who knew? Let’s start with taste. We taste because the chemicals in foods hit receptors on our tongues. Receptors for sweet, salt, bitter, sour, and umami (which can commonly be thought of as “savory”). Now, a receptor isn’t just a single protein, it’s actually several protein subunits working together to function. So, for example, the receptor subunit TAS1R3 is a subunit that can play two different tasting roles. When combined with one other subunit, it helps to sense sweet (like saccharin), and when combined with another, if helps you taste umami (like MSG, which is definitely umami flavored). If you get rid of the gene for TAS1R3, you end up with an animal that can’t detect either sweet or umami very well. There’s another subunit that is covered in this paper as well, GNAT3. GNAT3, instead of being specific for something like sweet or bitter, instead plays a role in “basic taste“. But these two protein subunits are not JUST expressed on the tongue and in the gastrointestinal tract. They are expressed elsewhere in the body…and especially in the testicles. © 2013 Scientific American

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 18336 - Posted: 07.02.2013