Chapter 16. None

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By Gretchen Reynolds. To handle stress and adversity more effectively, we should probably pay closer attention to what is happening inside our bodies, according to a fascinating new brain study of resilience and why some people seem to have more of it than others. We live in difficult times, as readers of this newspaper know well. Worries about the state of our world, our safety, our finances, health and more can lead to a variety of physiological and psychological responses. “When faced with stress, whether it’s giving a talk in front of a hundred people or feeling pressured to get a second gold medal at the Olympics, we experience changes in our body,” said Lori Haase, a clinical professor of psychiatry at the University of California in San Diego and lead author of the new study. Our heart rates rise, breathing grows shallow, and blood levels of adrenaline and other stress chemicals soar. While this stress response can have desirable results — “I need anxiety to motivate myself to write a grant,” Dr. Haase said — it can easily can get out of hand. Remaining in a state of heightened arousal undermines physical and mental performance, she explained. So while our bodies should respond to dangers and worries, our stress reactions also should dissipate as soon as possible afterward. This is where resilience comes in. In scientific terms, resilience is the ability to rapidly return to normal, both physically and emotionally, after a stressful event. Scientists and therapists long have known that some people are more resilient than others but had not known precisely why. © 2016 The New York Times Company

Keyword: Stress
Link ID: 21780 - Posted: 01.13.2016

By Virginia Morell Dog owners often say they “know” that their dog understands what they’re feeling. Now, scientists have the evidence to back this up. Researchers tested 17 adult dogs of various breeds to see whether they could recognize emotional expressions in the faces and voices of humans and other dogs—an ability that’s considered a higher cognitive talent because two different senses are involved. Each dog took part in two test sessions with 10 trials. One by one, they stood facing two screens on which the researchers projected photos of unfamiliar but happy/playful human or dog faces versus the same faces with angry/aggressive expressions (as in the photo above). At the same time, the scientists played a single vocalization—either a dog bark, or an unfamiliar human speaking in Portuguese, a language none of the dogs had previously heard, or a neutral sound. The dogs looked much longer at a face (dog or human) when the expression matched the tone of the voice, a measure that’s also been used to assess various cognitive abilities of other mammals, the scientists report online today in Biology Letters. The dogs were best at this when looking at a fellow dog, which supports another study showing that dogs preferred looking at images of other dogs rather than those of humans. It’s the first time that a species, other than humans, has been shown to be capable of interpreting the vocal and facial expressions of an entirely different species of animal—a talent that surely helps Fido survive in its ecological niche: the jungle of the human home. © 2016 American Association for the Advancement of Science.

Keyword: Emotions
Link ID: 21779 - Posted: 01.13.2016

Answered by Anne Masten, You raise one of the most intriguing questions in modern resilience science: Can adversity be good for development? The answer appears to be yes, depending on the timing and nature of the stresses. But it is important to note that it is a person's adaptive responses to life's challenges that are beneficial, not the exposure to adversity itself. Beneficial responses have been called steeling effects, stress inoculation and post-traumatic growth. Extreme deprivation or stress can clearly cause lasting life consequences. Yet many individuals endure, recover and thrive in the aftermath of devastating events. A few, such as Malala Yousafzai, Stephen Hawking or Oprah Winfrey, even become famous. What distinguishes them? An individual's resilience can be viewed as the capacity to adapt to adversity at a given point. Resilience is not innate, nor is it fixed. It can fluctuate throughout a person's lifetime and is influenced by a complex set of adaptive processes. Many of these protective systems improve with experience or require challenges to reach their full potential. On a biological and environmental level, our capabilities to fight off infections and respond to stress are both shaped by experience. For instance, we vaccinate our children to promote immunity to dangerous pathogens. Similarly, exposure to manageable levels of psychological stress can improve future adaptation abilities. It is important to remember, however, that too much adversity can deplete the resources any child or adult needs to muster resilience. There is psychological and neurobiological evidence that prolonged or overwhelming stress can wear down our body and mind. © 2016 Scientific American

Keyword: Stress
Link ID: 21775 - Posted: 01.12.2016

When Jack O'Connor was 19, he was so desperate to beat his addictions to alcohol and opioids that he took a really rash step. He joined the Marines. "This will fix me," O'Connor thought as he went to boot camp. "It better fix me or I'm screwed." After 13 weeks of sobriety and exercise and discipline, O'Connor completed basic training, but he started using again immediately. "Same thing," he says. "Percocet, like, off the street. Pills." Percocet is the brand name for acetaminophen and oxycodone. Oxycodone is a powerful opioid. It's one of the most commonly prescribed painkillers, and is a key factor in one of the country's most pressing public health problems — an opioid addiction epidemic. It is a crisis that started, in part, from the over-prescription of painkillers, like Percocet, and then shifted to heroin, as people addicted to prescription drugs looked for a cheaper high. O'Connor is one of an estimated 2.5 million Americans addicted to opioids and heroin, according to the National Institute on Drug Abuse. Over three years, he detoxed from prescription painkillers — and heroin — more than 20 times. Each time, he started using again. So why is it so hard for opioid addicts to quit? You can boil it down to two crucial bits of science: the powerful nature of opioids and the neuroscience behind how addiction hijacks the brain. "The first recording of opioid use was 5,000 years ago," says Dr. Seddon Savage, an addiction and pain specialist at Dartmouth College. It was "a picture of the opium poppy and the words 'the joy plant.' "

Keyword: Drug Abuse
Link ID: 21773 - Posted: 01.11.2016

Don’t blame impulsive people for their poor decisions. It’s not necessarily their fault. Impulsivity could result from not having enough time to veto our own actions. At least that is the implication of a twist on a classic experiment on free will. In 1983, neuroscientist Benjamin Libet performed an experiment to test whether we have free will. Participants were asked to voluntarily flex a finger while watching a clock-face with a rotating dot. They had to note the position of the dot as soon as they became aware of their intention to act. As they were doing so, Libet recorded their brain activity via EEG electrodes attached to the scalp. He found that a spike in brain activity called the readiness potential, which precedes a voluntary action, occurred about 350-milliseconds before the volunteers became consciously aware of their intention to act. The readiness potential is thought to signal the brain preparing for movement. Libet interpreted his results to mean that free will is an illusion. But we’re not complete slaves to our neurons, he reasoned, as there was a 200-millisecond gap between conscious awareness of our intention and the initiation of movement. Libet argued that this was enough time to consciously veto the action, or exert our “free won’t”. While Libet’s interpretations have remained controversial, this hasn’t stopped scientists carrying out variations of his experiment. Among other things, this has revealed that people with Tourette’s syndrome, who have uncontrollable tics, experience a shorter veto window than people without the condition, as do those with schizophrenia. © Copyright Reed Business Information Ltd.

Keyword: Consciousness; ADHD
Link ID: 21772 - Posted: 01.11.2016

By Christof Koch While “size does not matter” is a universally preached dictum among the politically correct, everyday experience tells us that this can't be the whole story—under many conditions, it clearly does. Consider the size of Woody Allen's second favorite organ, the brain. Adjectives such as “highbrow” and “lowbrow” have their origin in the belief, much expounded by 19th-century phrenologists, of a close correspondence between a high forehead—that is, a big brain—and intelligence. Is this true? Does a bigger brain make you necessarily smarter or wiser? And is there any simple connection between the size of a nervous system, however measured, and the mental powers of the owner of this nervous system? While the answer to the former question is a conditional “yes, somewhat,” the lack of any accepted answer to the second one reveals our ignorance of how intelligent behavior comes about. The human brain continues to grow until it reaches its peak size in the third to fourth decade of life. An MRI study of 46 adults of mainly European descent found that the average male had a brain volume of 1,274 cubic centimeters (cm3) and that the average female brain measured 1,131 cm3. Given that a quart of milk equals 946 cm3, you could pour a bit more than that into a skull without any of it spilling out. Of course, there is considerable variability in brain volume, ranging from 1,053 to 1,499 cm3 in men and between 975 and 1,398 cm3 in women. As the density of brain matter is just a little bit above that of water plus some salts, the average male brain weighs about 1,325 grams, close to the proverbial three pounds often cited in U.S. texts. © 2016 Scientific American

Keyword: Intelligence; Evolution
Link ID: 21768 - Posted: 01.09.2016

Pete Etchells Autonomous Sensory Meridian Response, or ASMR, is a curious phenomenon. Those who experience it often characterise it as a tingling sensation in the back of the head or neck, or another part of the body, in response to some sort of sensory stimulus. That stimulus could be anything, but over the past few years, a subculture has developed around YouTube videos, and their growing popularity was the focus of a video posted on the Guardian this last week. It’s well worth a watch, but I couldn’t help but feel it would have been a bit more interesting if there had been some scientific background in it. The trouble is, there isn’t actually much research on ASMR out there. To date, only one research paper has been published on the phenomenon. In March last year, Emma Barratt, a graduate student at Swansea University, and Dr Nick Davis, then a lecturer at the same institution, published the results of a survey of some 500 ASMR enthusiasts. “ASMR is interesting to me as a psychologist because it’s a bit ‘weird’” says Davis, now at Manchester Metropolitan University. “The sensations people describe are quite hard to describe, and that’s odd because people are usually quite good at describing bodily sensation. So we wanted to know if everybody’s ASMR experience is the same, and of people tend to be triggered by the same sorts of things.” The study asked a range of questions about where, when and why people watch ASMR videos, whether there was any consistency in ASMR-triggering content, as well as whether individuals felt it had any effect on their mood. There was a remarkable consistency across participants in terms of triggering content – whispering worked for the majority of people, followed by videos involving some sort of personal attention, crisp sounds, and slow movements. For the most part, participants reported that they watched ASMR videos for relaxation purposes, or to help them sleep or deal with stress. © 2016 Guardian News and Media Limited

Keyword: Pain & Touch
Link ID: 21767 - Posted: 01.09.2016

AUDIE CORNISH, HOST: It's unusual for an NFL player - a current player - to criticize the league, especially its handling of controversial issues like concussions or domestic violence, but author Johnny Anonymous has done just that. He's an offensive lineman who's written a book under that pseudonym. It's called "NFL Confidential." In it, he details his 2014 season, including training camp and his big break after a starting player gets injured. He's worried about being fired, so we've masked his voice. First, Johnny Anonymous says getting hurt is always on the mind of the player. ANONYMOUS: It's absolutely constant. The NFL's the only league, the only job you'll find in the world where we have a 100 percent injury rate. CORNISH: So walk us through the questions that come to mind for a player when they first hear that, you know, sickening sound and they're lying there on the field. What are you thinking? ANONYMOUS: For some guys, it's fear, which is why you'll see them kicking and screaming and crying, and some guys it's shock. I know for most of us - and probably all of us - the first thing you think is, I'm done; that's it. You think the injury's going to take the game away from you. CORNISH: So in a way, you know, this is how it happens, right, this discussion of, like, why do people take all the painkillers, you know, like, why do people defy doctors? ANONYMOUS: You have to. It's the only way you make it through. I can tell you right now, honestly, that if I am playing a game, I cannot complete that game without painkillers. I will not be an effective player. © 2016 npr

Keyword: Brain Injury/Concussion
Link ID: 21766 - Posted: 01.09.2016

By Josh Izaac Helmets can reduce the risk of traumatic brain injury by almost 20%. But what if we take so many risks when wearing them that we lose the protective edge they provide? This could be the case, according to a study published this week. Researchers observed 80 cyclists under the guise of an “eye-tracking experiment,” pretending to track their eye-motion via a head-mounted camera as the participants inflated a virtual balloon. For some of the participants, the “eye-tracking devices” were mounted on helmets, while others just wore baseball caps, as can be seen in the picture of the equipment above. The further they inflated the balloon without it popping, the higher their reward and their risk-taking score. Participants wearing helmets inflated their balloons on average 30% more than those who wore caps, the team reports in Psychological Science. The finding could affect how we approach safety design and training, the authors say, as increased risk-taking behavior when using safety equipment might counteract the perceived benefit of the equipment. But what causes this effect in the first place? The underlying mechanism might be related to the concept of “social priming,” where people’s actions towards others are altered subconsciously due to exposure to particular words, cues, objects, or symbols. Importantly, this is the first time social priming has been shown to change people’s behaviour even when they are not interacting with others, providing potential new insights into human behavior. So, next time you’re out riding with a helmet, think twice before attempting that wheelie. © 2016 American Association for the Advancement of Science

Keyword: Brain Injury/Concussion
Link ID: 21765 - Posted: 01.09.2016

Bruce Bower Youngsters befuddled by printed squiggles on the pages of a storybook nonetheless understand that a written word, unlike a drawing, stands for a specific spoken word, say psychologist Rebecca Treiman of Washington University in St. Louis and her colleagues. Children as young as 3 can be tested for a budding understanding of writing’s symbolic meaning, the researchers conclude January 6 in Child Development. “Our results show that young children have surprisingly advanced knowledge about the fundamental properties of writing,” Treiman says. “This knowledge isn’t explicitly taught to children but probably gained through early exposure to print from sources such as books and computers.” Researchers and theorists have previously proposed that children who cannot yet read don’t realize that a written word corresponds to a particular spoken word. Studies have found, for instance, that nonliterate 3- to 5-year-olds often assign different meanings to the same word, such as girl, depending on whether that word appears under a picture of a girl or a cup. Treiman’s investigation “is the first to show that kids as young as 3 have the insight that print stands for something beyond what’s scripted on the page,” says psychologist Kathy Hirsh-Pasek of Temple University in Philadelphia. Preschoolers who are regularly read to have an advantage in learning that written words have specific meanings, suspects psychologist Roberta Golinkoff of the University of Delaware in Newark. © Society for Science & the Public 2000 - 2015.

Keyword: Language; Dyslexia
Link ID: 21761 - Posted: 01.08.2016

By Anahad O'Connor David Ludwig often uses an analogy when he talks about weight loss: Human beings are not toaster ovens. If we were, then the types of calories we consumed would not matter, and calorie counting would be the most effective way to lose weight. Dr. Ludwig, an obesity expert and professor of nutrition at the Harvard T.H. Chan School of Public Health, argues that weight gain begins when people eat the wrong types of food, which throws their hormones out of whack and sets off a cycle of cravings, hunger and bingeing. In his new book, “Always Hungry?,” he argues that the primary driver of obesity today is not an excess of calories per se, but an excess of high glycemic foods like sugar, refined grains and other processed carbohydrates. Recently, we caught up with Dr. Ludwig to talk about which foods act as “fertilizer for fat cells,” why he thinks the conventional wisdom on weight loss is all wrong, and long-term strategies for weight loss. Here are edited excerpts from our conversation. What is the basic message of your book? The basic premise is that overeating doesn’t make you fat. The process of getting fat makes you overeat. It may sound radical, but there’s literally a century of science to support this point. Simply cutting back on calories as we’ve been told actually makes the situation worse. When we cut back on calories, our body responds by increasing hunger and slowing metabolism. It responds in an effort to save calories. And that makes weight loss progressively more and more difficult on a standard low calorie diet. It creates a battle between mind and metabolism that we’re doomed to lose. But we’ve all been told that obesity is caused by eating too much. Is that not the case? We think of obesity as a state of excess, but it’s really more akin to a state of starvation. If the fat cells are storing too many calories, the brain doesn’t have access to enough to make sure that metabolism runs properly. So the brain makes us hungry in an attempt to solve that problem, and we overeat and feel better temporarily. © 2016 The New York Times Company

Keyword: Obesity
Link ID: 21757 - Posted: 01.07.2016

Children conceived via infertility treatments are no more likely to have a developmental delay than children conceived without such treatments, according to a study by researchers at the National Institutes of Health, the New York State Department of Health and other institutions. The findings, published online in JAMA Pediatrics, may help to allay longstanding concerns that conception after infertility treatment could affect the embryo at a sensitive stage and result in lifelong disability. The authors found no differences in developmental assessment scores of more than 1,800 children born to women who became pregnant after receiving infertility treatment and those of more than 4,000 children born to women who did not undergo such treatment. “When we began our study, there was little research on the potential effects of conception via fertility treatments on U.S. children,” said Edwina Yeung, Ph.D., an investigator in the Division of Intramural Population Health Research at NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). “Our results provide reassurance to the thousands of couples who have relied on these treatments to establish their families.” Also taking part in the study were researchers from the University at Albany, New York; the New York State Department of Health, also in Albany; and CapitalCare Pediatrics in Troy, New York. The Upstate KIDS study enrolled infants born to women in New York State (except for New York City) from 2008 to 2010. Parents of infants whose birth certificates indicated infertility treatment were invited to enroll their children in the study, as were all parents of twins and other multiples. The researchers also recruited roughly three times as many singletons not conceived via infertility treatment. Four months after giving birth, the mothers indicated on a questionnaire the type of infertility treatment they received:

Keyword: Development of the Brain
Link ID: 21755 - Posted: 01.07.2016

Laura Sanders It didn’t take a lot of brainpower to come up with the name for a nerve cell that looks like a bushy, round tangle of fibers perched atop a nucleus. Meet the shrub cell. This botanically named cell, discovered in the brains of adult mice, made its formal debut in the Nov. 27 Science. The newly described cell lives in a particular nervy neighborhood — an area called layer 5 in the part of the brain that handles incoming visual information. Xiaolong Jiang of Baylor College of Medicine in Houston and colleagues defined shrub cells and other newcomers by their distinct shapes, their particular connections to other nerve cells or their similarities to nerve cells found elsewhere. Joining shrub cells are the freshly named horizontally elongated cells, deep-projecting cells, L5 basket cells and L5 neurogliaform cells. Each is an interneuron, a middleman that connects nerve cells to each other. The finding highlights the stunning variety of shapes and wiring patterns of cells in the brain. Citations X. Jiang et al. Principles of connectivity among morphologically defined cell types in adult neocortex. Science. Vol. 350, November 27, 2015. doi: 10.1126/science.aac9462 © Society for Science & the Public 2000 - 2015.

Keyword: Development of the Brain
Link ID: 21754 - Posted: 01.07.2016

by Helen Thompson Earth’s magnetic field guides shark movement in the open ocean, but scientists had always suspected that sharks might also get their directions from an array of other factors, including smell. To sniff out smell’s role, biologists clogged the noses of leopard sharks (Triakis semifasciata), a Pacific coastal species that makes foraging trips out to deeper waters. Researchers released the sharks out at sea and tracked their path back to the California coast over four hours. Sharks with an impaired sense of smell only made it 37.2 percent of the way back to shore, while unimpaired sharks made it 62.6 percent of the way back to shore. The study provides the first experimental evidence that smell influences a shark’s sense of direction, the team writes January 6 in PLOS ONE. The animals may be picking up on chemical gradients produced by food sources that live on the coast. © Society for Science & the Public 2000 - 2015.

Keyword: Chemical Senses (Smell & Taste); Animal Migration
Link ID: 21753 - Posted: 01.07.2016

A 25-year-old former college football player showed signs of a type of brain degeneration from repeated trauma, say researchers who described the autopsy-confirmed case. Chronic traumatic encephalopathy (CTE) is a neurodegenerative disorder associated with repetitive head impacts. Symptoms may include memory loss, impaired judgment, depression and progressive dementia. CTE can only be diagnosed after death by examining the brain. Monday's issue of JAMA Neurology includes a letter describing CTE in a 25-year-old man born with a heart valve disorder. He died of cardiac arrest secondary to a heart infection after playing football for 16 years and experiencing an estimated more than 10 concussions while playing. Dr. Ann McKee and Dr. Jesse Mez of Boston University School of Medicine ran neuropsychological tests on the man when he showed symptoms a year before his death, and then conducted an autopsy, reviewed his medical records and interviewed family members. "Focal lesions of CTE have been found in athletes as young as 17 years; however, widespread CTE pathology, as found in this case, is unusual in such a young football player," they wrote. To their knowledge, it's the first such case to include neuropsychological testing to document the type of cognitive issues with CTE. In this case, the athlete started playing football when he was six, including three years of college football as a defensive linebacker. His first concussion occurred at age eight. ©2015 CBC/Radio-Canada.

Keyword: Brain Injury/Concussion
Link ID: 21750 - Posted: 01.05.2016

By Melissa Healy A new study finds that policies on defining brain death vary from hospital to hospital and could result in serious errors. Since 2010, neurologists have had a clear set of standards and procedures to distinguish a brain-dead patient from one who might emerge from an apparent coma. But when profoundly unresponsive patients are rushed to hospitals around the nation, the physicians who make the crucial call are not always steeped in the diagnostic fine points of brain death and the means of identifying it with complete confidence. State laws governing the diagnosis of brain death vary widely. Some states allow any physician to make the diagnosis, while others dictate the level of specialty a physician making the call must have. Some require that a second physician confirm the diagnosis or that a given period of time elapse. Others make no such demands. Given these situations, hospital policies can be invaluable guides for physicians, hospital administrators and patients’ families. In the absence of consistent physician expertise or legal requirements, hospital protocols can translate a scientific consensus into a step-by-step checklist. That would help ensure that no one who is not brain-dead is denied further care or considered a potential organ donor and that the deceased and their families would have every opportunity to donate organs.

Keyword: Consciousness
Link ID: 21749 - Posted: 01.05.2016

By ALAN SCHWARZ DELRAY BEACH, Fla. — Three shaky months into recovery from heroin addiction, Dariya Pankova found something to ease her withdrawal. A local nonalcoholic bar sold a brewed beverage that soothed her brain and body much as narcotics had. A perfect solution — before it backfired. Ms. Pankova grew addicted to the beverage itself. She drank more and more, awakened her cravings for the stronger high of heroin, and relapsed. Only during another stay in rehab did Ms. Pankova learn that the drink’s primary ingredient, a Southeast Asian leaf called kratom, affects the brain like an opiate and can be addictive, too. “It’s preying on the weak and the broken,” said Ms. Pankova, 23, a Brooklyn native who received treatment in Delray Beach. “It’s a mind-altering substance, so people like me who are addicts and alcoholics, they think just because it’s legal, it’s fine. It’s a huge epidemic down here, and it’s causing a lot of relapses.” Some users embrace kratom as a natural painkiller and benign substitute for more dangerous substances that, in most states, is legal. But its growing popularity and easy availability are raising concerns among substance abuse experts and government officials who say it is being furtively marketed as a way out of addiction, even though it is itself addictive. Worse, some of those experts say, kratom can lead some addicts back to heroin, which is cheaper and stronger. “It’s a fascinating drug, but we need to know a lot more about it,” said Dr. Edward W. Boyer, a professor of emergency medicine at the University of Massachusetts Medical School and a co-author of several scientific articles on kratom. “Recreationally or to self-treat opioid dependence, beware — potentially you’re at just as much risk” as with an opiate. Concern is particularly high in South Florida, where a rising concentration of drug-treatment providers has coincided with the sprouting of kratom bars. But kratom is now available around the country. © 2016 The New York Times Company

Keyword: Drug Abuse
Link ID: 21747 - Posted: 01.04.2016

By Ana Swanson Earlier this year, the famous blue-and-black (or white-and-gold) dress captivated the Internet, serving as a reminder that color is truly in the eye of the beholder. The dress was also a lesson in the power of social media, the science of shifting colors, and the fun of optical illusions. Here we present a visual story from February 27 that rounded up some of the best-known optical illusions on the Web. The Internet erupted in an energetic debate yesterday about whether an ugly dress was blue and black or white and gold, with celebrities from Anna Kendrick (white) to Taylor Swift (black) weighing in. (For the record, I’m with Taylor – never a bad camp to be in.) It sounds inane, but the dress question was actually tricky: Some declared themselves firmly in the blue and black camp, only to have the dress appear white and gold when they looked back a few hours later. Wired had the best explanation of the science behind the dress’s shifting colors. When your brain tries to figure out what color something is, it essentially subtracts the lighting and background colors around it, or as the neuroscientist interviewed by Wired says, tries to “discount the chromatic bias of the daylight axis.” This is why you can identify an apple as red whether you see it at noon or at dusk. The dress is on some kind of perceptual boundary, with a pretty even mix of blue, red and green. (Frankly, it’s just a terrible, washed out photo.) So for those who see it as white, your eyes may be subtracting the wrong background and lighting.

Keyword: Vision
Link ID: 21742 - Posted: 01.02.2016

By Mitch Leslie Male mice bequeath an unexpected legacy to their progeny. Two studies published online this week in Science reveal that sperm from the rodents carry pieces of RNAs that alter the metabolism of their offspring. The RNAs spotlighted by the studies normally help synthesize proteins, so the findings point to an unconventional form of inheritance. The results are “exciting and surprising, but not impossible,” says geneticist Joseph Nadeau of the Pacific Northwest Diabetes Research Institute in Seattle, Washington. “Impossible” is exactly how biologists once described so-called epigenetic inheritance, in which something other than a DNA sequence passes a trait between generations. In recent years, however, researchers have found many examples. A male mouse’s diet and stress level, for instance, can tweak offspring metabolism. Researchers are still trying to determine how offspring inherit a father’s metabolic attributes and physiological condition. Some evidence implicates chemical modification of DNA. Other work by neuroscientist Tracy Bale of the University of Pennsylvania Perelman School of Medicine in Philadelphia and colleagues has found that mammalian sperm pack gene-regulating molecules called microRNAs. The new work highlights a different class of RNAs, transfer RNAs (tRNAs). In one study, genomicist Oliver Rando of the University of Massachusetts Medical School in Worcester and colleagues delved into a case of epigenetic inheritance in which the progeny of mice fed a low-protein diet show elevated activity of genes involved in cholesterol and lipid metabolism. When Rando’s group analyzed sperm from the protein-deprived males, they uncovered an increased abundance of fragments from several kinds of tRNAs. The researchers concluded the sperm acquired most of these fragments while passing through the epididymis, a duct from the testicle where the cells mature. © 2016 American Association for the Advancement of Science

Keyword: Epigenetics
Link ID: 21741 - Posted: 01.02.2016

By KARL OVE KNAUSGAARD I arrived in Tirana, Albania, on a Sunday evening in late August, on a flight from Istanbul. The sun had set while the plane was midflight, and as we landed in the dark, images of fading light still filled my mind. The man next to me, a young, red-haired American wearing a straw hat, asked me if I knew how to get into town from the airport. I shook my head, put the book I had been reading into my backpack, got up, lifted my suitcase out of the overhead compartment and stood waiting in the aisle for the door up ahead to open. That book was the reason I had come. It was called “Do No Harm,” and it was written by the British neurosurgeon Henry Marsh. His job is to slice into the brain, the most complex structure we know of in the universe, where everything that makes us human is contained, and the contrast between the extremely sophisticated and the extremely primitive — all of that work with knives, drills and saws — fascinated me deeply. I had sent Marsh an email, asking if I might meet him in London to watch him operate. He wrote a cordial reply saying that he seldom worked there now, but he was sure something could be arranged. In passing, he mentioned that he would be operating in Albania in August and in Nepal in September, and I asked hesitantly whether I could join him in Albania. Now I was here. Tense and troubled, I stepped out of the door of the airplane, having no idea what lay ahead. I knew as little about Albania as I did about brain surgery. The air was warm and stagnant, the darkness dense. A bus was waiting with its engine running. Most of the passengers were silent, and the few who chatted with one another spoke a language I didn’t know. It struck me that 25 years ago, when this was among the last remaining Communist states in Europe, I would not have been allowed to enter; then, the country was closed to the outside world, almost like North Korea today. Now the immigration officer barely glanced at my passport before stamping it. She dully handed it back to me, and I entered Albania. © 2015 The New York Times Company

Keyword: Consciousness
Link ID: 21739 - Posted: 12.30.2015