Chapter 16. None

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|By Daniel Yudkin Imagine you are with some friends at a concert, and the bouncer approaches the group and says that, because you are all looking so ravishing tonight, he’s been instructed to offer one of you—just one!—a backstage pass to meet the artist. Do you raise your hand? For most people, this would be a no-brainer: who wouldn’t leap at the chance to meet a famous singer or secure a long-sought autograph? The results of a recent study, published in Psychological Science by Gus Cooney, Daniel Gilbert, and Timothy Wilson, however, suggest taking a second’s pause before snapping up that backstage pass. Cooney, Gilbert, and Wilson suspected that extraordinary experiences—like meeting a musical idol—carry hidden costs. They hypothesized that, while such occurrences undoubtedly make us happier in the moment, they also risk separating us from our peers, leading to a sense of isolation so unpleasant as to outweigh whatever enjoyment they initially confer. To test this idea, the researchers recruited subjects in groups of four and had them watch a video clip. Of the group, three were told that they would watch a clip that previous viewers had given a 2-star rating; the remaining subject, by contrast, was granted the opportunity to view a special 4-star clip. After watching the videos, all four subjects were given some time to talk amongst themselves, and then each reported on their general happiness. © 2015 Scientific American

Keyword: Emotions
Link ID: 20527 - Posted: 01.28.2015

Ian Sample, science editor People who carry a mutated gene linked to longer lifespan have extra tissue in part of the brain that seems to protect them against mental decline in old age. The finding has shed light on a biological pathway that researchers now hope to turn into a therapy that slows the progression of Alzheimer’s disease and other forms of dementia. Brain scans of more than 400 healthy men and women aged 53 and over found that those who carried a single copy of a particular gene variant had a larger brain region that deals with planning and decision making. Further tests on the group found that those with an enlarged right dorsolateral prefrontal cortex (rDLPFC), as the brain region is known, fared better on a series of mental tasks. About one in five people inherits a single copy of the gene variant, or allele, known as KL-VS, which improves heart and kidney function, and on average adds about three years to human lifespan, according to Dena Dubal, a neurologist at University of California, San Francisco. Her latest work suggests that the same genetic mutation has broader effects on the brain. While having a larger rDLPFC accounted for only 12% of the improvement in people’s mental test scores, Dubal suspects the gene alters the brain in other ways, perhaps by improving the connections that form between neurons.

Keyword: Alzheimers; Genes & Behavior
Link ID: 20526 - Posted: 01.28.2015

By Eliot Marshall In perhaps the most famous study of childhood neglect, researchers have closely tracked the progress, or lack of it, in children who lived as infants in Romania’s bleak orphanages and are now teenagers. A new analysis now shows that these children, who display a variety of behavioral and cognitive problems, have less white matter in their brains than do a group of comparable children in local families. The affected brain regions include nerve bundles that support attention, general cognition, and emotion processing. The work suggests that sensory deprivation early in life can have dramatic anatomical impacts on the brain and may help explain the previously documented long-term negative affects on behavior. But there’s some potential good news: A small group of children who were taken out of orphanages and moved into foster homes at age 2 appeared to bounce back, at least in brain structure. “This is an exciting and important study,” says Harvard Medical School psychiatric researcher Martin Teicher, who directs the developmental biopsychiatry research program at McLean Hospital in Belmont, Massachusetts. The “crucial question” of whether children can recover from the setbacks of early adversity had not been answered before, he adds. The work is based on MRI scans and other measures taken in Romania by researchers at the Bucharest Early Intervention Project (BEIP). The group, headed by neurologist Charles Nelson of Harvard Medical School, was spurred to action by the collapse of Romania’s Nicolae Ceauceșcu regime in 1989, which had shunted tens of thousands of unwanted children into state-run orphanages. Nelson says that caretakers in the orphanages worked in factorylike shifts; children might see as many as 17 different caretakers in a week. Infants rarely enjoyed the one-on-one interactions that are considered essential to normal development. © 2015 American Association for the Advancement of Science

Keyword: Development of the Brain; Brain imaging
Link ID: 20524 - Posted: 01.27.2015

|By Christof Koch Faces are the glue that holds us together and that gives us our identity. All of us but the visually impaired and blind are experts at recognizing people's identity, gender, age and ethnicity from looking at their faces. First impressions of attractiveness or competence take but a brief glimpse of somebody's face. Newly born infants already tend to fixate on faces. This bias also turns up in art. Paintings and movies are filled with faces staring at the viewer. Who can forget the endless close-ups of the feuding husband and wife in Ingmar Bergman's Cimmerian masterpiece Scenes from a Marriage? Because recognizing a face is so vital to our social lives, it comes as no surprise that a lot of real estate in the cerebral cortex—the highly convoluted region that makes up the bulk of our brain—is devoted to a task crucial to processing faces and their identity. We note whether someone looks our way or not. We discern emotional expressions, whether they register joy, fear or anger. Indeed, functional brain imaging has identified a set of adjacent regions, referred to as the fusiform face area (FFA), that are situated on the left and the right sides of the brain, at the bottom of the temporal lobe of the cerebral cortex. The FFA turns up its activity when subjects look at portraits or close-ups of faces or even when they just think about these images. Two just published studies of the brain's visual networks, including the FFA, enlarge what we know about the physical basis of face perception. Both explore the unique access to the brain afforded by patients whose epileptic seizures have proved resistant to drugs. A surgical treatment finds the locations in the brain where the hypersynchronized activity that characterizes a seizure begins before spreading from its point of origin to engulf one or sometimes both hemispheres. If a single point—a focus where the seizure begins—can be found, it can be removed. After this procedure, a patient usually has significantly fewer seizures—and some remain seizure-free. To triangulate the location of the focus, neurosurgeons insert electrodes into the brain to monitor electrical activity that occurs during a seizure. © 2015 Scientific American

Keyword: Attention
Link ID: 20523 - Posted: 01.27.2015

David Cox Bernd Heinrich was on a hike through the woods of New England when he observed something which would go on to change our perception of animal psychology. A group of ravens had gathered to feed on a dead moose. But rather than choosing to keep the bounty for themselves, they were making a strange call, one which seemed to be deliberately attracting more ravens to the feast. A biologist at the University of Vermont, Heinrich was initially confused. By helping their competitors, the ravens appeared to be defying all natural biological instinct. But as it transpired, their motivation was actually deeply selfish. The birds were juveniles who had discovered the moose in an adult raven’s territory. By inviting other ravens to join them, their intrusion was more likely to go unchallenged. Last month, an astonishing video emerged of a rhesus macaque successfully resuscitating another of its species which had been electrocuted at a train station in India. It is tempting to describe the sustained display of persistence and apparent concern as almost human. But there is a danger in viewing animal behaviour through the misty lens of human emotion. What both Heinrich’s “sharing ravens’ and the macaques of Kampur do provide is a window into the gradual evolution of one of the most human of traits – altruism. Altruism in its purest form should be an entirely selfless action. “If there’s any kind of selfish interest at stake, like secretly hoping for a return favour or even doing it deliberately because you know it will make you feel good, then that doesn’t really count at all,” says psychologist Michael Platt of the Center for Cognitive Neuroscience at Duke University, North Carolina.

Keyword: Aggression; Intelligence
Link ID: 20522 - Posted: 01.27.2015

By Will Boggs MD (Reuters Health) – There are so many different genetic forms of autism that using the singular term, autism, is misleading, researchers say. “We believe a better term to use is ‘the autisms,’ or ‘the autism spectrum disorders’ (that is, plural),” Dr. Stephen W. Scherer told Reuters Health by email. “There are many different forms of autism. In other words, autism is more of a collection of different disorders that have a common clinical manifestation.” The DNA of affected individuals varies remarkably, his team found. Two-thirds of brothers and sisters with what’s still called autism spectrum disorder, or ASD, showed different genetic changes. Scherer, from The Hospital for Sick Children in Toronto, Ontario, Canada, is part of a team that aims to identify all the genetic changes in individuals with ASD. In the U.S., the Centers for Disease Control and Prevention (CDC) estimates that 1 in 68 children (1 in 42 boys and 1 in 189 girls) have an autism spectrum disorder. Recent estimates in Europe, the CDC says, are that one to two percent of children there are affected. When Scherer's team looked for genetic changes in the entire DNA from 85 pairs of brothers and sisters with ASD and their parents, they found an average of roughly 73 genetic changes per set of DNA -- but only 36 of the 85 families (42.4 percent) had mutations that researchers could relate to genes already linked in some way to ASD. © 2015 Scientific American

Keyword: Autism
Link ID: 20520 - Posted: 01.27.2015

|By Tori Rodriguez Scientists have studied brain structure for decades, so most disease-related structural anomalies have been long known. New findings of this nature are rare—yet last summer one neuroscientist studying depression published just that. Over nine years of sorting through countless brain images, Jerome J. Maller of Monash University and Alfred Hospital in Melbourne noticed a particular type of brain abnormality that seemed to show up more often in depressed patients. Their occipital lobes were often wrapped around each other. Maller and his colleagues investigated further and found that depressed patients are indeed three times as likely to have wraparound lobes. Occipital bending occurred in 35.3 percent of the depressed patients and 12.5 percent of the control subjects, according to their paper, published in Brain. The effect was even more pronounced in women: 45.8 percent of female patients with major depressive disorder exhibited occipital bending versus only 5.9 percent of women without depression, possibly because women's brains fit more snugly in their skulls than men's do. Previous studies have also found that occipital bending is more common in patients with schizophrenia. Maller suggests the lobes may wrap around each other when space for brain growth becomes constricted, perhaps because the brain is not doing enough neural pruning—the process by which the brain gets rid of neurons that are no longer needed. Indeed, many other studies have found that depressed brains are hyperconnected. Maller does not know if the finding will have clinical implications beyond helping to diagnose depression, but experts hope that this avenue of research will eventually lead to a deeper understanding of the disorder. “It really suggests some significant biological basis for at least some forms of depression,” says William Hopkins, a professor of neuroscience at Georgia State University, who was not involved in the study. © 2015 Scientific American

Keyword: Depression; Brain imaging
Link ID: 20518 - Posted: 01.26.2015

By Ling Xin For many, the hardest part of learning to speak Chinese is mastering its complex tonal variations. Now, new research suggests a surprising explanation for how those tones arose: a humid climate. By examining the correlation between humidity and the role of tone in more than 3700 languages, scientists found that tonal languages are remarkably rare in arid regions like Central Europe, whereas languages with complex tone pitches are prevalent in relatively humid regions such as the tropics, subtropical Asia, and Central Africa. Humidity keeps the voice box moist and elastic, allowing it to produce correct and complex tones, the scientists explain online this month in the Proceedings of the National Academy of Sciences. “If the United Kingdom had been a humid jungle, English may also have developed into a tonal language,” they claim. So, next time you go to your Chinese class, don’t forget to wet your whistle! © 2015 American Association for the Advancement of Science.

Keyword: Language
Link ID: 20517 - Posted: 01.26.2015

By Tina Hesman Saey Gustometer guhs-TOH-meh-ter n. A device used to squirt measured amounts of liquids into the mouth of a person in a taste study. Researchers often pair the instrument with brain scanning technology. Recently, a study of wine tasting pitted 10 of the top sommeliers from France and Switzerland against 10 novices. Researchers led by Lionel Pazart of Besançon University Hospital in France custom-built a gustometer to conduct the blind taste test. The scientists compared how brain activity changed when people tasted chardonnay, pinot noir or water. When sipping wine, the experts had greater activity in several parts of their brains, including regions involved in memory, than novices did, the researchers report in October in Frontiers in Behavioral Neuroscience. Sommeliers’ expertise may allow them to process sensory input about a wine — its taste and bouquet — while simultaneously recalling other information, such as the reputation of the winery that produced the beverage. Citations L. Pazart et al. An fMRI study on the influence of sommeliers’ expertise on the integration of flavor. Frontiers in Behavioral Neuroscience Vol. 8, October 16, 2014. doi: 10.3389/fnbeh.2014.00358. © Society for Science & the Public 2000 - 2015.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 20516 - Posted: 01.26.2015

Simon Parkin A few months before she died, my grandmother made a decision. Bobby, as her friends called her (theirs is a generation of nicknames), was a farmer’s wife who not only survived World War II but also found in it justification for her natural hoarding talent. ‘Waste not, want not’ was a principle she lived by long after England recovered from a war that left it buckled and wasted. So she kept old envelopes and bits of cardboard cereal boxes for note taking and lists. She kept frayed blankets and musty blouses from the 1950s in case she needed material to mend. By extension, she was also a meticulous chronicler. She kept albums of photographs of her family members. She kept the airmail love letters my late grandfather sent her while he travelled the world with the merchant navy in a box. Her home was filled with the debris of her memories. Yet in the months leading up to her death, the emphasis shifted from hoarding to sharing. Every time I visited my car would fill with stuff: unopened cartons of orange juice, balls of fraying wool, damp, antique books, empty glass jars. All things she needed to rehome now she faced her mortality. The memories too began to move out. She sent faded photographs to her children, grandchildren and friends, as well as letters containing vivid paragraphs detailing some experience or other. On 9 April, the afternoon before the night she died, she posted a letter to one of her late husband’s old childhood friends. In the envelope she enclosed some photographs of my grandfather and his friend playing as young children. “You must have them,” she wrote to him. It was a demand but also a plea, perhaps, that these things not be lost or forgotten when, a few hours later, she slipped away in her favourite armchair. © 2015 BBC

Keyword: Consciousness; Robotics
Link ID: 20515 - Posted: 01.26.2015

by Catherine Brahic Move over Homo habilis, you're being dethroned. A growing body of evidence – the latest published this week – suggests that our "handy" ancestor was not the first to use stone tools. In fact, the ape-like Australopithecus may have figured out how to be clever with stones before modern humans even evolved. Humans have a way with flint. Sure, other animals use tools. Chimps smash nuts and dip sticks into ant nests to pull out prey. But humans are unique in their ability to apply both precision and strength to their tools. It all began hundreds of thousands of years ago when a distant ancestor began using sharp stone flakes to scrape meat off skin and bones. So who were those first toolmakers? In 2010, German researchers working in Ethiopia discovered markings on two animal bones that were about 3.4 million years old. The cut marks had clearly been made using a sharp stone, and they were at a site that was used by Lucy's species, Australopithecus afarensis. The study, led by Shannon McPherron of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, was controversial. The bones were 800,000 years older than the oldest uncontested stone tools, and at the time few seriously thought that australopithecines had been tool users. Plus, McPherron hadn't found the tool itself. The problem, says McPherron, is that if we just go on tools that have been found, we must conclude that one day somebody made a beautifully flaked Oldowan hand axe, completely out of the blue. That seems unlikely. © Copyright Reed Business Information Ltd.

Keyword: Evolution
Link ID: 20512 - Posted: 01.23.2015

by Linda Geddes OUR personality literally shapes our world. It helps determine how many friends we have, which jobs we excel in and how we cope with adversity. Now it seems it may even play a role in our health – and not just in terms of any hypochondriac tendencies we harbour, but also how prone our bodies are to getting sick in the first place. It is a provocative idea but one that has been steadily gaining traction. We think of conscientiousness, for example, as a positive trait because it suggests caution, careful planning and an aversion to potential danger. But could it also be a symptom of underlying weakness in the immune system? That's one interpretation of a study published last month that sought to pick apart the links between personality traits and the immune system. It found that highly conscientious people had lower levels of inflammation; an immune response that helps the body fight infection and recover from injury. Highly extrovert people had higher levels. This may mean that extroverts are more physically robust – at least while they're young. While this sounds like good news, there's also a downside since sustained inflammation over a lifetime may leave you vulnerable to diabetes, atherosclerosis and cancer. "The biggest take-home message is that what happens in our health is connected to what happens in our heads and what happens in our lives," says Steven Cole at the University of California in Los Angeles (UCLA), who supervised the research. © Copyright Reed Business Information Ltd.

Keyword: Neuroimmunology
Link ID: 20510 - Posted: 01.22.2015

By Rachel Feltman Fear is one of our most basic evolutionary instincts, a sudden physical jolt to help us react to danger more quickly. In the modern world, fear often seems excessive -- in the absence of wild animals to flee, we're left screaming over roller coasters and scary movies. But for at least one woman, fear is unobtainable. And while she lives a normal life, her fearlessness is actually a handicap. The researchers who study her keep her closely guarded, using the code-name "SM" when publishing papers about her brave brainpower. And until this year, she'd never been interviewed. "Tell me what fear is," Tranel began. "Well, that's what I'm trying to -- to be honest, I truly have no clue," SM said, her voice raspy. That's actually a symptom of the condition that stole fear from her. Urbach-Wieth disease, which is characterized by a hoarse voice, small bumps around the eyes, and calcium deposits in the brain is rare in its own right -- only 400 people on the planet are known to have it -- but in SM's case, some of those brain-deposits happened to take over her amygdalae. These almond-shaped structures deep inside the brain are crucial to human fear response. And in SM's case, they've been totally calcified since she was a young woman. Now in her 40s, her fear-center is as good as gone. "It's a little bit as if you would go to this region and literally scoop it out," Antonio Damasio, another neuroscientist who studies SM, told "Invisibilia" hosts Lulu Miller and Alix Spiegel.

Keyword: Emotions
Link ID: 20504 - Posted: 01.21.2015

Oliver Burkeman One spring morning in Tucson, Arizona, in 1994, an unknown philosopher named David Chalmers got up to give a talk on consciousness, by which he meant the feeling of being inside your head, looking out – or, to use the kind of language that might give a neuroscientist an aneurysm, of having a soul. Though he didn’t realise it at the time, the young Australian academic was about to ignite a war between philosophers and scientists, by drawing attention to a central mystery of human life – perhaps the central mystery of human life – and revealing how embarrassingly far they were from solving it. The scholars gathered at the University of Arizona – for what would later go down as a landmark conference on the subject – knew they were doing something edgy: in many quarters, consciousness was still taboo, too weird and new agey to take seriously, and some of the scientists in the audience were risking their reputations by attending. Yet the first two talks that day, before Chalmers’s, hadn’t proved thrilling. “Quite honestly, they were totally unintelligible and boring – I had no idea what anyone was talking about,” recalled Stuart Hameroff, the Arizona professor responsible for the event. “As the organiser, I’m looking around, and people are falling asleep, or getting restless.” He grew worried. “But then the third talk, right before the coffee break – that was Dave.” With his long, straggly hair and fondness for all-body denim, the 27-year-old Chalmers looked like he’d got lost en route to a Metallica concert. “He comes on stage, hair down to his butt, he’s prancing around like Mick Jagger,” Hameroff said. “But then he speaks. And that’s when everyone wakes up.”

Keyword: Consciousness
Link ID: 20503 - Posted: 01.21.2015

The presence of a romantic partner during painful medical procedures could make women feel worse rather than better, researchers say. A small study found this increase in pain was most pronounced in women who tended to avoid closeness in their relationships. The authors say bringing a loved one along for support may not be the best strategy for every patient. The work appears in the journal Social Cognitive and Affective Neuroscience. Researchers from University College London, King's College London and the University of Hertfordshire say there has been very little scientific research into the effects of a partner's presence on someone's perception of pain, despite this being common medical advice. They recruited 39 heterosexual couples and asked them a series of questions to measure how much they sought or avoided closeness and emotional intimacy in relationships. Each female volunteer was then subjected to a series of painful laser pulses while her partner was in and then out of the room. The women were asked to score their level of pain. They also had their brain activity measured using a medical test called an EEG. The researchers found that certain women were more likely to score high levels of pain while their partner was in the room. These were women who said they preferred to avoid closeness, trusted themselves more than their partners and felt uncomfortable in their relationships. © 2015 BBC

Keyword: Pain & Touch
Link ID: 20502 - Posted: 01.21.2015

By JOHN MARKOFF A new laboratory technique enables researchers to see minuscule biological features, such as individual neurons and synapses, at a nearly molecular scale through conventional optical microscopes. In a paper published last week in the journal Science, researchers at M.I.T. said they were able to increase the physical size of cultured cells and tissue by as much as five times while still preserving their structure. The scientists call the new technique expansion microscopy. The idea of making objects larger to make them more visible is a radical solution to a vexing challenge. By extending the resolving power of conventional microscopes, scientists are able to glimpse such biological mysteries as the protein structures that form ion channels and the outline of the membrane that holds the genome within a cell. The researchers have examined minute neural circuits, gaining new insights into local connections in the brain and a better understanding of larger networks. The maximum resolving power of conventional optical microscopes is about 200 nanometers, about half the wavelength of visible light. (By contrast, a human hair is about 500 times wider.) In recent decades, scientists have struggled to push past these limits. Last year, three scientists received a Nobel Prize for a technique in which fluorescent molecules are used to extend the resolving power of optical microscopes. But the technique requires specialized equipment and is costly. With expansion microscopy, Edward S. Boyden, a co-director of the M.I.T. Center for Neurobiological Engineering, and his colleagues were able to observe objects originally measuring just 70 nanometers in cultured cells and brain tissue through an optical microscope. © 2015 The New York Times Company

Keyword: Brain imaging
Link ID: 20499 - Posted: 01.20.2015

By Christie Aschwanden Maybe it’s their famously protruding brow ridge or perhaps it’s the now-discredited notion that they were primitive scavengers too dumb to use language or symbolism, but somehow Neanderthals picked up a reputation as brutish, dim and mannerless cretins. Yet the latest research on the history and habits of Neanderthals suggests that such portrayals of them are entirely undeserved. It turns out that Neanderthals were capable hunters who used tools and probably had some semblance of culture, and the DNA record shows that if you trace your ancestry to Europe or Asia, chances are very good that you have some Neanderthal DNA in your own genome. The bad rap began when the first Neanderthal skull was discovered around 1850 in Germany, says Paola Villa, an archaeologist at the University of Colorado. “The morphological features of these skulls — big eyebrows, no chin — led to the idea that they were very different from us, and therefore inferior,” she says. While the majority of archaeologists no longer believe this, she says, the idea that Neanderthals were inferior, brutish or stupid remains in popular culture. Neanderthals first appeared in Europe and western Asia between 300,000 and 400,000 years ago. They are our closest (extinct) relative, and their species survived until 30,000 to 40,000 years ago, when they vanish from the fossil record, says Svante Paabo, director of the Max Planck Institute of Evolutionary Anthropology in Leipzig, Germany, and author of “Neanderthal Man: In Search of Lost Genomes.” Why these relatives of ours thrived for so long and then ended their long, successful run about the same time that modern humans began to spread remains a point of debate and speculation.

Keyword: Evolution
Link ID: 20498 - Posted: 01.20.2015

// by Jennifer Viegas Researchers eavesdropping on wild chimpanzees determined that the primates communicate about at least two things: their favorite yummy fruits, and the trees where these fruits can be found. Of particular interest to the chimps is the size of trees bearing the fruits that they relish most, such that the chimps yell out that information, according to a new study published in the journal Animal Behaviour. The study is the first to find that information about tree size and available fruit amounts are included in chimp calls, in addition to assessments about food quality. "Chimpanzees definitely have a very complex communication system that includes a variety of vocalizations, but also facial expressions and gestures," project leader Ammie Kalan of the Max Planck Institute for Evolutionary Anthropology told Discovery News. "How much it resembles human language is still a matter of debate," she added, "but at the very least, research shows that chimpanzees use vocalizations in a sophisticated manner, taking into account their social and environmental surroundings." Kalan and colleagues Roger Mundry and Christophe Boesch spent over 750 hours observing chimps and analyzing their food calls in the Ivory Coast's Taï Forest. The Wild Chimpanzee Foundation in West Africa is working hard to try and protect this population of chimps, which is one of the last wild populations of our primate cousins. © 2015 Discovery Communications, LLC

Keyword: Language; Evolution
Link ID: 20497 - Posted: 01.20.2015

Helen Fisher, a biological anthropologist at Rutgers University responds: Several years ago I embarked on a project to see if the seven-year itch really exists. I began by studying worldwide data on marriage and divorce and noticed that although the median duration of marriage was seven years, of the couples who divorced, most did so around their fourth year together (the “mode”). I also found that divorce occurred most frequently among couples at the height of their reproductive and parenting years—for men, ages 25 to 29, and for women, ages 20 to 24 and 25 to 29—and among those with one dependent child. To try to explain these findings, I began looking at patterns of pair bonding in birds and mammals. Although only about 3 percent of mammals form a monogamous bond to rear their young, about 90 percent of avian species team up. The reason: the individual that sits on the eggs until they hatch will starve unless fed by a mate. A few mammals are in the same predicament. Take the female fox: the vixen produces very thin milk and must feed her young almost constantly, so she relies on her partner to bring her food while she stays in the den to nurse. But here's the key: although some species of birds and mammals bond for life, more often they stay together only long enough to rear their young through infancy and early toddlerhood. When juvenile robins fly away from the nest or maturing foxes leave the den for the last time, their parents part ways as well. Humans retain traces of this natural reproductive pattern. In more contemporary hunter-gatherer societies, women tend to bear their children about four years apart. Moreover, in these societies after a child is weaned at around age four, the child often joins a playgroup and is cared for by older siblings and relatives. This care structure allows unhappy couples to break up and find a more suitable partner with whom to have more young. © 2015 Scientific American

Keyword: Sexual Behavior; Evolution
Link ID: 20496 - Posted: 01.20.2015

By PAULA SPAN DEDHAM, Mass. — Jerome Medalie keeps his advance directive hanging in a plastic sleeve in his front hall closet, as his retirement community recommends. That’s where the paramedics will look if someone calls 911. Like many such documents, it declares that if he is terminally ill, he declines cardiopulmonary resuscitation, a ventilator and a feeding tube. But Mr. Medalie’s directive also specifies something more unusual: If he develops Alzheimer’s disease or another form of dementia, he refuses “ordinary means of nutrition and hydration.” A retired lawyer with a proclivity for precision, he has listed 10 triggering conditions, including “I cannot recognize my loved ones” and “I cannot articulate coherent thoughts and sentences.” If any three such disabilities persist for several weeks, he wants his health care proxy — his wife, Beth Lowd — to ensure that nobody tries to keep him alive by spoon-feeding or offering him liquids. VSED, short for “voluntarily stopping eating and drinking,” is not unheard-of as an end-of-life strategy, typically used by older adults who hope to hasten their decline from terminal conditions. But now ethicists, lawyers and older adults themselves have begun a quiet debate about whether people who develop dementia can use VSED to end their lives by including such instructions in an advance directive. Experts know of just a handful of people with directives like Mr. Medalie’s. But dementia rates and numbers have begun a steep ascent, already afflicting an estimated 30 percent of those older than 85. Baby boomers are receiving a firsthand view of the disease’s devastation and burdens as they care for aging parents. They may well prove receptive to the idea that they shouldn’t be kept alive if they develop dementia themselves, predicted Alan Meisel, the director of the University of Pittsburgh’s Center for Bioethics and Health Law. © 2015 The New York Times Company

Keyword: Alzheimers
Link ID: 20495 - Posted: 01.20.2015