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/ By Venkat Srinivasan It started as a tremor in his left hand and arm. It seemed harmless, but it surprised him. He was a gardener in his 50s and had no history of rheumatism or seizures or any other significant pain. He brushed it off at first, chalking it up to the exhausting daily work. But it wouldn’t go away. Writing and reading became difficult. He could not direct his fork to his mouth, and had to be fed. “It’s like a Russian doll. Within each molecule, there are so many functions.” It was the early 1800s, and a surgeon in London had started to collect notes — not just on the gardener but on a number of patients with similar symptoms. Their hands simply failed “to answer with exactness to the dictates of the will.” The years dragged on; the disease spread to the gardener’s legs, and his trunk started to bow significantly. People couldn’t understand him when he spoke. He passed urine without knowing. The tremors became more and more violent, waking him at night. Nobody understood what he was suffering from. Finally, in 1817, Dr. James Parkinson published an essay on this shaking palsy. He apologized for his speculative approach, writing that “analogy is the substitute for anatomical examination, the only sure foundation for pathological knowledge.” Two centuries later, the disease named for Parkinson is still a puzzle. It is now known that the telltale external symptoms — rigidity, slow movement, a resting tremor — result from a loss of dopamine-rich neurons in a region of the brain called the substantia nigra. But the complete network of steps leading to this cell death is still vague, and the underlying causes remain one of medicine’s great mysteries. Copyright 2018 Undark

Keyword: Parkinsons
Link ID: 24763 - Posted: 03.16.2018

by Laurie McGinley The Food and Drug Administration on Thursday took the first concrete action to reduce nicotine in cigarettes to make them much less addictive, opening a regulatory process described as a “historic first step” by the agency's top official. Commissioner Scott Gottlieb unveiled an “advance notice of proposed rulemaking,” the earliest step in what promises to be a long, complicated regulatory effort to lower nicotine levels to be minimally addictive or nonaddictive. The notice, to be published Friday in the Federal Register, includes new data published in the New England Journal of Medicine on Thursday based on a possible policy scenario. That FDA-funded analysis found that slashing nicotine levels could push the smoking rate down to 1.4 percent from the current 15 percent of adults. That in turn would result in 8 million fewer tobacco-related deaths through the end of the century — which Gottlieb termed “an undeniable public health benefit.” The evaluation was based on reducing nicotine levels to 0.4 milligrams per gram of tobacco filler, FDA officials told reporters during a teleconference. Many adults try to quit smoking each year but fail because nicotine is such an addictive substance, said Mitch Zeller, director of the FDA's Center for Tobacco Products. Cutting the nicotine level would not only help them succeed, but it also could keep young people who may be experimenting with cigarettes from becoming addicted, he said. The nicotine notice will be open for public comment for 90 days. FDA officials are seeking input on what the maximum nicotine level in cigarettes should be and whether such a limit should be implemented all at once or gradually. Nicotine levels can be manipulated by leaf blending, chemical extraction and genetic engineering. © 1996-2018 The Washington Post

Keyword: Drug Abuse
Link ID: 24762 - Posted: 03.16.2018

Paula Span At first, the pills helped her feel so much better. Jessica Falstein, an artist living in the East Village in Manhattan, learned she had an anxiety disorder in 1992. It led to panic attacks, a racing pulse, sleeplessness. “Whenever there was too much stress, the anxiety would become almost intolerable, like acid in the veins,” she recalled. When a psychopharmacologist prescribed the drug Klonopin, everything brightened. “It just leveled me out,” Ms. Falstein said. “I had more energy. And it helped me sleep, which I was desperate for.” After several months, however, the horrible symptoms returned. “My body became accustomed to half a milligram, and the drug stopped working,” she said. “So then I was up to one milligram. And then two.” Her doctor kept increasing the dosage and added Ativan to the mix. Now 67, with her health and stamina in decline, Ms. Falstein has been diligently working to wean herself from both medications, part of the class called benzodiazepines that is widely prescribed for insomnia and anxiety. “They turn on you,” she said. For years, geriatricians and researchers have sounded the alarm about the use of benzodiazepines among older adults. Often called “benzos,” the problem drugs include Valium (diazepam), Klonopin (clonazepam), Xanax (alprazolam) and Ativan (lorazepam). The cautions have had scant effect: Use of the drugs has risen among older people, even though they are particularly vulnerable to the drugs’ ill effects. Like Ms. Falstein, many patients take them for years, though they’re recommended only for short periods. The chemically related “z-drugs” — Ambien, Sonata and Lunesta — present similar risks. © 2018 The New York Times Company

Keyword: Development of the Brain; Drug Abuse
Link ID: 24761 - Posted: 03.16.2018

By Anna Azvolinsky Researchers have tried to dissect the effects of an older father on kids’ longevity. One study found that kids with older dads had longer telomeres, which may indicate better health and longer lifespan, while another observed that kids with older dads have an increased risk of psychiatric disorders. So far, there have been very few experimental studies in animals that directly test whether paternal age has an affect on offspring telomere length and lifespan. Now, a team of researchers shows that bird embryos sired from old zebra finch fathers have shorter telomeres compared to those with the same moms and younger fathers. The study, published today (March 14) in Proceedings of the Royal Society B, is among the first to address whether paternal age affects telomere length of offspring using an experimental approach. “The experimental design of this study looking at the effect of paternal age on telomere length of [zebra finch] embryos is particularly strong, allowing for confidence in these results,” writes Dan Eisenberg, an anthropologist at the University of Washington who studies the effects of paternal age on telomere length in humans and chimpanzees, in an email to The Scientist. Jose Noguera, now at the University of Vigo, along with colleagues at the University of Glasgow, bred 32 middle-aged, female zebra finches first with both 16 four-month-old males and later with 16 four-year-old male birds. The team harvested the eggs, 139 in total, artificially incubated them for several days, then analyzed the telomere lengths of the embryos. © 1986-2018 The Scientist

Keyword: Development of the Brain; Sexual Behavior
Link ID: 24760 - Posted: 03.16.2018

Jeff Tollefson Early humans in eastern Africa crafted advanced tools and displayed other complex behaviours tens of thousands of years earlier than previously thought, according to a trio of papers published on 15 March in Science1,2,3. Those advances coincided with — and may have been driven by — major climate and landscape changes. The latest evidence comes from the Olorgesailie Basin in Southern Kenya, where researchers have previously found traces of ancient relatives of modern human as far back as 1.2 million years ago. Evidence collected at sites in the basin suggests that early humans underwent a series of profound changes at some point before roughly 320,000 years ago. They abandoned simple hand axes in favour of smaller and more advanced blades made from obsidian and other materials obtained from distant sources. That shift suggests the early people living there had developed a trade network — evidence of growing sophistication in behaviour. The researchers also found gouges on black and red rocks and minerals, which indicate that early Olorgesailie residents used those materials to create pigments and possibly communicate ideas. All of these changes in human behaviour occurred during an extended period of environmental upheaval, punctuated by strong earthquakes and a shift towards a more variable and arid climate. These changes occurred at the same time as larger animals disappeared from the site and were replaced by smaller creatures. “It’s a one-two punch combining tectonic shifts and climate shifts,” says Rick Potts, who led the work as director of the human origins programme at the Smithsonian Institution in Washington DC. “That’s the kind of stuff out of which evolution arises.” Researchers from the Smithsonian Institution digging in the Olorgesailie Basin in Kenya. © 2018 Macmillan Publishers Limited

Keyword: Evolution
Link ID: 24759 - Posted: 03.16.2018

By Hiroko Tabuchi If a sparrow sings his heart out on an oil field, but his would-be sweetheart can’t hear him above the oil pumps, what’s a bird to do? In Alberta, Canada, researchers analyzed hundreds of hours of Savannah sparrow love songs and discovered something extraordinary: To be heard above the din, the birds are changing their tune in complex ways that scientists are only starting to understand. “They’re tailoring their songs depending on which part of their message is the most affected,” said Miyako Warrington, a University of Manitoba biologist who led a recent study on how sparrows cope with noise from the oil and gas infrastructure that dots Canada’s landscape. “This seems to show a complex level of adaptation. It’s not just everybody talking louder.” Dr. Warrington is one of a growing number of scholars who study the noise generated by human activity — drills, turbines, roaring jet engines — and how that affects the natural world around us. Mining on the fringes of the Brazilian rain forest, for instance, is disrupting the calls of local black-fronted titi monkeys, a study found last year. Whales and dolphins are known to be particularly vulnerable to the groans of ship engines or offshore drilling, which can disrupt the complex ways they communicate. Research has shown that noise pollution has doubled the background sound levels in more than 60 percent of protected areas in the United States. And humans are not immune to the din. Epidemiologists have linked traffic noise to cardiovascular and other diseases. © 2018 The New York Times Company

Keyword: Animal Communication; Sexual Behavior
Link ID: 24758 - Posted: 03.15.2018

by Ben Guarino Only male birds sing. For years that was the assumption among amateur birdwatchers and ornithologists alike. After all, male birds are “the obvious ones,” says Lauryn Benedict, a biologist at the University of Northern Colorado. “They're out there showing off, strutting their stuff.” But Benedict and fellow birdsong expert Karan Odom, a biologist at Cornell University, want you to look closer if you hear a chirp or warble. Female birds are not, on the whole, silent. In a call-to-ears published Wednesday in the journal the Auk, the two scientists say that “birders and researchers need to be aware that female birds regularly sing, and they need to take the time to evaluate the sex of singing birds.” The tipping point for Odom came in 2014, when she concluded that birdsong is an ancestral trait shared by both sexes. Female birds sang in 71 percent of 323 species surveyed, she and her colleagues reported then in a Nature Communications paper. They traced this behavior through the bird family tree, winding back the generations to a common singing ancestor. At that point in history, they wrote, both male and female birds sang. Benedict, who was not involved with that work, described it like this: Instead of males evolving to be loud, “females have evolved to be quiet.” © 1996-2018 The Washington Post

Keyword: Animal Communication; Sexual Behavior
Link ID: 24757 - Posted: 03.15.2018

By RICH MONAHAN “You must really love that song,” my mother says, and for a moment my heart stops. Both of us are plainly aware she need not be more specific than that. I attempt to read her body language out of the corner of my eye. Does she know? There’s no way, right? “Yeah, it’s a favorite.” I nod, smiling, before turning back toward the television with what I hope is all the nonchalance of a typical 14-year-old boy. What I definitely do not do is glance back and say, “Funny story about that song, while you’ve clearly noticed I’ve listened to it every single weeknight this entire school year, would you believe I only ever press play at exactly 8:38 p.m.? “And check this out, once that cable box hits 9:52 p.m., I will casually retire to my bedroom to initiate the final sequence of what has recently ballooned into a nearly 90-minute nightly routine of humiliating compulsions: I’ll touch the same four CDs laid out on my dresser in ‘order’; turn the stereo on and off; move to the entertainment center; touch the ‘Twisted Metal’ video game case; turn on the TV; boot up the PlayStation; shut it off once the load screen finishes; press ‘channel up’ on the cable box until I hit channel 20, then 22, then 40; turn off the cable box, then touch nothing else until it’s lights out at 9:58 p.m. “And that’s not even the craziest part; the craziest part is that I do these things because I believe they will somehow increase my social standing among other ninth graders. Anywho, Mom, the song’s called ‘Daysleeper,’ and I’m pretty sure I’ve lost my mind.” It started in seventh grade, when two childhood friends aged out of hanging out with me. Already depressed and on the verge of friendlessness, I was desperate to preserve life as it had been. © 2018 The New York Times Company

Keyword: OCD - Obsessive Compulsive Disorder
Link ID: 24756 - Posted: 03.15.2018

By Abby Olena Diagnosing neurobiological disorders, such as the autism spectrum disorders, focuses on complex clinical evaluations. But a study published last week (March 6) in eLife shows that an objective measure—how the pupil varies in size while viewing an optical illusion—reveals differences in perceptual styles and correlates with a self-reported score of autistic traits. The findings suggest that tracking fluctuations in pupil size, which is called pupillometry, could be used alongside clinical assessments to help researchers and clinicians understand autism. “We used to think that the pupil was a simple light reflex or that it just indexed arousal,” says Stefan Van der Stigchel, an attention and perception researcher at Utrecht University in the Netherlands who did not participate in the work. This study shows “how the pupil can be informative of, in this situation, perceptual styles.” Previous research has shown that people with autism spectrum disorders allocate their attention differently—and therefore may perceive things differently—than people in the general population. For instance, rather than perceiving an image as a forest, they might focus on the individual trees, says coauthor David Burr of the University of Florence. It’s possible to measure what people pay attention to by having them look at images with both bright and dark areas. Their pupils are slightly larger when they attend to the dark parts and slightly smaller when they attend to the light parts. Burr, Paola Binda of the University of Pisa in Italy, and Marco Turi, a postdoc at the University of Pisa, decided to take advantage of this phenomenon and study how attention, via pupil size, tracks with autistic traits. © 1986-2018 The Scientist

Keyword: Autism; Attention
Link ID: 24755 - Posted: 03.15.2018

Researchers at the University of Calgary say they have developed a portable brain-imaging system that would literally shed light on concussions. Symptoms of a concussion can vary greatly between individuals and include headaches, nausea, loss of memory and lack of co-ordination, which make it difficult to find treatment options. U of C scientist Jeff Dunn says there has been no accepted way to get an image of a concussion, but he and his team have developed a device, called a Near-Infrared Spectroscopy, that measures communication in the brain by measuring oxygen levels in blood. Results show these patterns change after concussion. The device — a cap that contains small lights with sensors connected to a computer — is placed on the top of the head to monitor and measure brain activity while the patient looks at a picture or does a simple activity. "When the brain activates, blood flow goes up but oxygen levels also go up, so the blood actually becomes redder as the brain activates," Dunn said. "And we measure that so we shine a light in and we can see that change in oxygen level and measure the change in absorption." Dunn hopes the images will show a connection between symptoms and abnormalities in the brain that could help doctors identify treatment protocols and recovery timelines. ©2018 CBC/Radio-Canada

Keyword: Brain Injury/Concussion; Brain imaging
Link ID: 24754 - Posted: 03.15.2018

Sue Blackmore Are you longing for your brain and all its memories to be preserved for ever? That once fanciful idea seems creepily closer now that a complete pig’s brain has been successfully treated, frozen, rewarmed and found to have its neural connections still intact. This achievement, by the cryobiology research company 21st Century Medicine (21CM), has just won the final phase of the Brain Preservation Foundation’s prize – a prize that demanded all of a brain’s synaptic connections be preserved in a way that allowed for centuries-long storage of the entire information content of a whole large mammal’s brain. They used a pig’s brain, which was perfused with lethal glutaraldehyde before being frozen at –135C, a method called aldehyde-stabilised cryopreservation (ASC). This process kills any chance of the brain being brought to life again, but they won because when the treated brain was warmed up again its connectome – the brain’s wiring diagram – was amazingly well preserved. In fact it was so well preserved that even the fine ultrastructural details of dendritic spine synapses could still be seen with a 3D electron microscope. This means potentially 150 trillion connections, all of which may be implicated in storing memory. A human brain treated this way could never be brought back to life. Yet all its preserved information could potentially be uploaded into an artificial or virtual body indistinguishable from the previously living one – like “uploading a person’s mind” after a long wait. Would this then be “you”? © 2018 Guardian News and Media Limited

Keyword: Consciousness
Link ID: 24753 - Posted: 03.15.2018

By SANDRA BLAKESLEE Dr. T. Berry Brazelton, America’s most celebrated baby doctor since Benjamin Spock and the pediatrician who revolutionized our understanding of how children develop psychologically, died on Tuesday at his home in Barnstable, Mass., on Cape Cod. He was 99. His daughter Christina Brazelton confirmed the death. Before Dr. Brazelton began practicing medicine in the early 1950s, the conventional wisdom about babies and child rearing was unsparingly authoritarian. It was believed that infants could not feel pain. Parents were instructed to set strict schedules, demand obedience and refrain from kissing or cuddling. Babies were to be fed every four hours, by the clock, preferably from a bottle. When children were hospitalized, parents were allowed few if any visiting hours. Dr. Brazelton, echoing Dr. Spock, whose book “The Common Sense Book of Baby and Child Care” became a best seller in 1946, rejected such beliefs and practices as being senseless, if not barbaric. “He put the baby at the center of the universe,” Dr. Barry Lester, a pediatrician and director of the Center for the Study of Children at Risk at Brown University, said in an interview for this obituary in 2009. “We take for granted all the changes he helped bring about. He more than anyone is responsible for the return to natural childbirth, breast feeding and the ability of parents to stay with a hospitalized child.” Nevertheless, Dr. Brazelton’s work never entered mainstream pediatrics and is not taught in most medical curriculums. But the public loved the charismatic Dr. Brazelton. He wrote nearly 40 books and a column in Family Circle magazine, and he was the host of an Emmy Award-winning show, “What Every Baby Knows,” which ran for 12 years on the Lifetime cable channel. He also worked with Congress to pass parental leave legislation and other parent-friendly measures. © 2018 The New York Times Company

Keyword: Development of the Brain
Link ID: 24752 - Posted: 03.15.2018

By Frankie Schembri When you go to catch a Frisbee, you don’t need to stare at your hand until it makes contact. You have an intuitive sense of where your arm is—and where it’s going—based on how your muscles and joints feel. This sense of body position, known as kinesthesia, has proved tricky to build into prosthetic arms. Now, researchers have recreated the feeling of kinesthesia in six arm amputees by sending finely tuned vibrations into the skin of their upper arms and shoulders. The approach improved their ability to feel and control their prosthetic arms when performing actions such as gripping and pinching, the team reports today in Science Translational Medicine. The amputees in the study had previously undergone surgery to rewire the nerves in their upper bodies to act as messengers for the specific electric signals associated with arm and hand movement. Three also completed tests where they were asked to close their hand as if gripping a cylinder, while not being able to see their prosthetic arm. When the subjects performed the task again while receiving kinesthesia vibrations simulating the feeling of the motion, they more instinctively moved their prosthetics into the grip and were faster in correcting their mistakes, such as when some of their fingers had not closed into the grip. The subjects also indicated in surveys that they felt greater control over their prosthetic arms when receiving the kinesthesia vibrations. The authors of the study say that more experiments need to be run in order to determine the effectiveness of the vibrations in helping with everyday activities such as picking up objects, and on a test group larger than six people. © 2018 American Association for the Advancement of Science

Keyword: Pain & Touch; Robotics
Link ID: 24751 - Posted: 03.15.2018

Laura Sanders We can’t see it, but brains hum with electrical activity. Brain waves created by the coordinated firing of huge collections of nerve cells pinball around the brain. The waves can ricochet from the front of the brain to the back, or from deep structures all the way to the scalp and then back again. Called neuronal oscillations, these signals are known to accompany certain mental states. Quiet alpha waves ripple soothingly across the brains of meditating monks. Beta waves rise and fall during intense conversational turns. Fast gamma waves accompany sharp insights. Sluggish delta rhythms lull deep sleepers, while dreamers shift into slightly quicker theta rhythms. Researchers have long argued over whether these waves have purpose, and what those purposes might be. Some scientists see waves as inevitable but useless by-products of the signals that really matter — messages sent by individual nerve cells. Waves are simply a consequence of collective neural behavior, and nothing more, that view holds. But a growing body of evidence suggests just the opposite: Instead of by-products of important signals, brain waves are key to how the brain operates, routing information among far-flung brain regions that need to work together. MIT’s Earl Miller is among the neuro­scientists amassing evidence that waves are an essential part of how the brain operates. Brain oscillations deftly route information in a way that allows the brain to choose which signals in the world to pay attention to and which to ignore, his recent studies suggest. |© Society for Science & the Public 2000 - 2018

Keyword: Attention
Link ID: 24750 - Posted: 03.14.2018

By Rachel R. Albert Parents are often their own worst critics when it comes to imparting knowledge to their children. Although helping with science fairs or homework assignments may come later on, the pressure comes early, as their infant starts to babble in increasingly word-like vocalizations. It’s easy to assume that children who can’t yet form a word are unable to understand what their parents are saying to them. But spend just a few minutes with an infant, and you quickly realize how rapidly the gears are turning. And new research by me and my colleagues Michael Goldstein and Jennifer Schwade at Cornell University, suggests these interactions are more sophisticated than we once thought. Parents’ responses to their baby’s babbling take on new significance at the age of about six months, when babies’ vocalizations start to mature. Around this age, babies become incredibly receptive to what they hear immediately after they babble. In fact, previous work from the B.A.B.Y. Lab at Cornell University suggests that if infants receive a response to their initial vocalization, they’re far more likely to vocalize again. Observations of mother-infant conversations have found that within 10 minutes of this type of exchange, children can be taught new vocalizations. For example, they can be taught to shift their consonant-vowel construction of “dada” into vowel-consonant “ada.” But what’s truly incredible about these exchanges is the level of influence babies have as actual conversation partners. © 2018 Scientific American,

Keyword: Language; Development of the Brain
Link ID: 24749 - Posted: 03.14.2018

To understand the link between aging and neurodegenerative disorders such as Alzheimer’s disease, scientists from the National Institutes of Health compared the genetic clocks that tick during the lives of normal and mutant flies. They found that altering the activity of a gene called Cdk5 appeared to make the clocks run faster than normal, and the flies older than their chronological age. This caused the flies to have problems walking or flying later in life, to show signs of neurodegeneration, and to die earlier. “We tried to untangle the large role aging appears to play in some of the most devastating neurological disorders,” said Edward Giniger, Ph.D., senior investigator at the NIH’s National Institute of Neurological Disorders and Stroke and the senior author of the study published in Disease Models & Mechanisms. “Our results suggest that neurodegenerative disorders may accelerate the aging process.” On average, the normal flies in this study lived for 47 days. To create a genetic clock, Dr. Giniger’s team measured the levels of every gene encoded in messenger RNA molecules from cells from the heads and bodies of flies at 3, 10, 30, and 45 days after birth. This allowed the researchers to use advanced analysis techniques to search for the genes that seemed to be sensitive to aging, and create a standard curve, or timeline, that described the way they changed. When they performed the same experiments on 10-day-old mutant flies and compared the results with the standard curve, they found that the flies were “older” than their chronological age. Altering Cdk5 activity made the brains of the flies appear genetically to be about 15 days old and their bodies to be about 20 days old.

Keyword: Biological Rhythms
Link ID: 24748 - Posted: 03.14.2018

Geoff Brumfiel Sergei Skripal and his daughter, Yulia, were found slumped on a bench in the city of Salisbury on March 4. Experts quickly assessed that Skripal — a former Russian intelligence official accused of spying for the British — had been poisoned with a nerve agent. On Monday, British Prime Minister Theresa May named the agent in a speech before Parliament. "It is now clear that Mr. Skripal and his daughter were poisoned with a military-grade nerve agent of a type developed by Russia," she said. "This is part of a group of nerve agents known as Novichok." Novichok agents are extremely rare. "As far as I know, I don't know anybody who knows how to make it except these guys in Russia," says Dan Kaszeta, a chemical weapons expert with Strongpoint Security in London. "They've been a deep, dark secret." Novichok means "newcomer" in Russian. Kaszeta says that Novichok agents were developed in the 1980s as a new weapon in the waning days of the Cold War. Novichok chemicals were designed to evade equipment carried by NATO troops. "They wanted to develop nerve agents that the West couldn't detect," he says. According to a defector's report published by the Stimson Center in 1995, they were developed at the State Scientific Research Institute of Organic Chemistry and Technology in Moscow. As the U.S. and Russia were laying the groundwork to dismantle their chemical weapons stockpiles, researchers at the institute were working in secret to develop the new Novichok chemicals. © 2018 npr

Keyword: Neurotoxins
Link ID: 24747 - Posted: 03.13.2018

By Nicola Davis Your book is all about reproductive hormones, and their impact on our behaviour. It only focuses on female hormones. Why not look at men’s too? Two reasons. One is that the focus of research in my lab is to look at women’s hormones. The other is that I think there are problems with how people have viewed hormones and women, and I really want to debunk those myths, then pursue some of the implications for further exploring links between women’s hormones and their behaviour. I think they are really important for women’s wellbeing. You say that some people, including women, have pushed back against discussing the influence of hormones. Why is that? I get a strong sense that if you ascribe a woman’s behaviour to biology, people will automatically think that women are automatons, driven by their hormones and unable to regulate their own behaviour. That is false. There is a female stereotype, whereby any time a woman does something a little bit difficult to understand, then it is hormones that make women “irrational”. But nobody says that about men. For that reason, those who are concerned about women achieving equality with men worry that if we talk about women and hormones, then people will say such things as women shouldn’t hold higher office and so on. That’s silly, because men have hormones, too. Are you surprised by how recently we have begun investigating the impact of hormones on women? One reason is that scientists were content for many decades with studying the male as the default sex, and that was in part because women had cycles that made them messy. If you are doing a scientific experiment, you don’t want noise, you don’t want variation, you want everything to be strictly controlled. © 2018 Guardian News and Media Limited

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 24746 - Posted: 03.13.2018

NIH-funded researchers at Stanford University used the gene editing tool CRISPR-Cas9 to rapidly identify genes in the human genome that might modify the severity of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) caused by mutations in a gene called C9orf72. The results of the search, published in Nature Genetics, uncovered a new set of genes that may hasten neuron death during the disease. Accounting for nearly 40 percent of inherited cases of ALS and 25 percent of inherited FTD cases, disease-causing mutations in C9orf72 insert extra sequences of DNA, called hexanucleotide repeats, into the gene. These repeats produce potentially toxic RNA and protein molecules that kill neurons resulting in problems with movement and eventually paralysis for ALS patients and language and decision-making problems for FTD patients. Led by Aaron D. Gitler, Ph.D., and Michael C. Bassik, Ph.D., the researchers used CRISPR to disable each gene, one-by-one, in a line of human leukemia cells and then tested whether the cells would survive exposure to toxic proteins derived from the hexanucleotide repeats, called DPRs. Any disabled genes that caused cells to live longer or die faster than normal were considered suspects in DPR toxicity. They confirmed that genes that control the movement of molecules in and out of a cell’s nucleus may be partners. They also identified several new players, including genes that modify chromosomes and that help cells assemble proteins passing through a maze-like structure called the endoplasmic reticulum (ER). A second CRISPR search conducted on mouse brain cells confirmed the initial results. Disabling the top 200 genes identified in the leukemia cells helped neurons survive DPR exposure.

Keyword: ALS-Lou Gehrig's Disease ; Alzheimers
Link ID: 24745 - Posted: 03.13.2018

Shankar Vedantam Economic theory rests on a simple notion about humans: people are rational. They seek out the best information. They measure costs and benefits, and maximize pleasure and profit. This idea of the rational economic actor has been around for centuries. But about 50 years ago, two psychologists shattered these assumptions. They showed that people routinely walk away from good money. And they explained why, once we get in a hole, we often keep digging. Think Fast with Daniel Kahneman The methods of these psychologists were as unusual as their insights. Instead of writing complex theorems, Daniel Kahneman and Amos Tversky spent hours together...talking. They came up with playful thought experiments. They laughed a lot. "We found our mistakes very funny," recalls Kahneman. "What was fun was finding yourself about to say something really stupid." The insights that Kahneman developed with Tversky, who passed away in 1996, transformed the way we understand the mind. That transformation also had philosophical implications. "The stories about the past are so good that they create an illusion that life is understandable, and they create an illusion that you can predict the future," Kahneman says. Daniel Kahneman won the Nobel prize in 2002, and over the past 99 episodes of Hidden Brain, we've drawn extensively on research inspired by his work. This week, we celebrate our 100th episode by interviewing Kahneman about judgment, memory, and the mind itself. He spoke with us before a live audience at NPR headquarters in Washington, D.C. © 2018 npr

Keyword: Learning & Memory; Emotions
Link ID: 24744 - Posted: 03.13.2018