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By Gunjan Sinha Light therapy can help lift moods, heal wounds, and boost the immune system. Can it improve symptoms of Parkinson’s disease, too? A first-of-its-kind trial scheduled to launch this fall in France aims to find out. In seven patients, a fiber optic cable implanted in their brain will deliver pulses of near-infrared (NIR) light directly to the substantia nigra, a region deep in the brain that degenerates in Parkinson’s disease. The team, led by neurosurgeon Alim- Louis Benabid of the Clinatec Institute—a partnership between several government-funded research institutes and industry—hopes the light will protect cells there from dying. The study is one of several set to explore how Parkinson’s patients might benefit from light. “I am so excited,” says neuropsychologist Dawn Bowers of the University of Florida College of Medicine, who is recruiting patients for a trial in which NIR will be beamed into the skull instead of delivered with an implant. Small tests in people with Parkinson’s and animal models of the disease have already suggested benefits, but some mainstream Parkinson’s researchers are skeptical. No one has shown exactly how light might protect the key neurons—or why it should have any effect at all on cells buried deep in the brain that never see the light of day. Much or all of the encouraging hints seen so far in people may be the result of the placebo effect, skeptics say. Because there are no biomarkers that correlate well with changes in Parkinson’s symptoms, “we are reliant on observing behavior,” says neurobiologist David Sulzer of Columbia University Irving Medical Center, an editor of the journal npj Parkinson’s Disease. “It’s not easy to guard against placebo effects.” © 2020 American Association for the Advancement of Science

Keyword: Parkinsons
Link ID: 27482 - Posted: 09.19.2020

Ken Solt & Oluwaseun Akeju The state of dissociation is commonly described as feeling detached from reality or having an ‘out of body’ experience. This altered state of consciousness is often reported by people who have psychiatric disorders arising from devastating trauma or abuse. It is also evoked by a class of anaesthetic drug, and can occur in epilepsy. The neurological basis of dissociation has been a mystery, but writing in Nature, Vesuna et al.1 describe a localized brain rhythm that underlies this state. Their findings will have far-reaching implications for neuroscience. The authors first recorded brain-wide neuronal activity in mice using a technique called widefield calcium imaging. They studied changes in these brain rhythms in response to a range of drugs that have sedative, anaesthetic or hallucinogenic properties, including three that induce dissociation — ketamine, phencyclidine (PCP) and dizocilpine (MK801). Only the dissociative drugs produced robust oscillations in neuronal activity in a brain region called the retrosplenial cortex. This region is essential for various cognitive functions, including episodic memory and navigation2. The oscillations occurred at a low frequency, of about 1–3 hertz. By contrast, non-dissociative drugs such as the anaesthetic propofol and the hallucinogen lysergic acid diethylamide (LSD) did not trigger this rhythmic retrosplenial activity. Vesuna et al. examined the active cells in more detail using a high-resolution approach called two-photon imaging. This analysis revealed that the oscillations were restricted to cells in layer 5 of the retrosplenial cortex. The authors then recorded neuronal activity across multiple brain regions. Normally, other parts of the cortex and subcortex are functionally connected to neuronal activity in the retrosplenial cortex; however, ketamine caused a disconnect, such that many of these brain regions no longer communicated with the retrosplenial cortex. © 2020 Springer Nature Limited

Keyword: Drug Abuse; Consciousness
Link ID: 27481 - Posted: 09.19.2020

Jon Hamilton Scientists used light to control the firing of specific cells to artificially create a rhythm in the brain that acted like the drug ketamine enjoynz/Getty Images Out-of-body experiences are all about rhythm, a team reported Wednesday in the journal Nature. In mice and one person, scientists were able to reproduce the altered state often associated with ketamine by inducing certain brain cells to fire together in a slow, rhythmic fashion. "There was a rhythm that appeared, and it was an oscillation that appeared only when the patient was dissociating," says Dr. Karl Deisseroth, a psychiatrist and neuroscientist at Stanford University. Dissociation is a brain state in which a person feels separated from their own thoughts, feelings and body. It is common in people who have some mental illnesses or who have experienced a traumatic event. It can also be induced by certain drugs, including ketamine and PCP (angel dust). The study linking dissociation to brain rhythms represents "a big leap forward in understanding how these drugs produce this unique state," says Dr. Ken Solt, an anesthesiologist at Harvard Medical School and Massachusetts General Hospital. Solt is the co-author of an article that accompanied the study but was not involved in the research. The finding also could be a step toward finding non-drug methods to control states of consciousness, Solt says. Deisseroth's lab made the discovery while studying the brains of mice that had been given ketamine or other drugs that cause dissociation. The team was using technology that allowed them to monitor the activity of cells throughout the brain. © 2020 npr

Keyword: Drug Abuse; Consciousness
Link ID: 27480 - Posted: 09.19.2020

By Rebekah Tuchscherer Call it neuroscience on the go. Scientists have developed a backpack that tracks and stimulates brain activity as people go about their daily lives. The advance could allow researchers to get a sense of how the brain works outside of a laboratory—and how to monitor diseases such as Parkinson’s and post-traumatic stress disorder in real-world settings. The technology is “an inspiring demonstration of what’s possible” with portable neuroscience equipment, says Timothy Spellman, a neurobiologist at Weill Cornell Medicine who was not involved with the work. The backpack and its vast suite of tools, he says, could broaden the landscape for neuroscience research to study the brain while the body is in motion. Typically, when scientists want to scan the brain, they need a lot of room—and a lot of money. Functional magnetic resonance imaging (fMRI) scanners, which detect activity in various regions of the brain, are about the size of a pickup truck and can cost more than $1 million. And patients must stay still in the machine for about 1 hour to ensure a clear, readable scan. © 2020 American Association for the Advancement of Science.

Keyword: Brain imaging
Link ID: 27479 - Posted: 09.19.2020

By William Wan If only Dan Goerke could hold his wife’s hand. Maybe she would talk again. Maybe she would look at him and smile as she used to. Maybe she would eat and stop wasting away. Since the pandemic began, Goerke’s wife, Denise — 63 years old and afflicted with Alzheimer’s disease — had declined dramatically. Left alone in her nursing home, she had lost 16 pounds, could not form the simplest words, no longer responded to the voices of her children. In recent weeks, she had stopped recognizing even the man she loved. Goerke, 61, could tell the isolation was killing his wife, and there was nothing he could do but watch. “Every day it gets a little worse,” he said. “We’ve lost months, maybe years of her already.” Beyond the staggering U.S. deaths caused directly by the novel coronavirus, more than 134,200 people have died from Alzheimer’s and other forms of dementia since March. That is 13,200 more U.S. deaths caused by dementia than expected, compared with previous years, according to an analysis of federal data by The Washington Post. Overlooked amid America’s war against the coronavirus is this reality: People with dementia are dying not just from the virus but from the very strategy of isolation that’s supposed to protect them. In recent months, doctors have reported increased falls, pulmonary infections, depression and sudden frailty in patients who had been stable for years. Social and mental stimulation are among the few tools that can slow the march of dementia. Yet even as U.S. leaders have rushed to reopen universities, bowling alleys and malls, nursing homes say they continue begging in vain for sufficient testing, protective equipment and help.

Keyword: Alzheimers
Link ID: 27478 - Posted: 09.19.2020

By Laura J. Snyder I’m an inveterate storyteller,” confesses the celebrated neurologist and writer Oliver Sacks at the start of Oliver Sacks: His Own Life. “I tell many stories, some comic, some tragic.” Tales of both types abound in this elegiac yet lighthearted film based on director Ric Burns’s interviews with Sacks and his friends, colleagues, family members, and patients in the months before and after the physician’s death in 2015 at the age of 82. The result is a vivid portrait of an ebullient, provocative, brilliant man who transformed the practice of medicine and spearheaded the neurodiversity movement. Born into an upper-middle-class Jewish family in northwest London in 1933, Sacks was the youngest of four sons. He was an outsider: one of only three Jews at his elite prep school; a gay adolescent at a time when gay sex was illegal; an introverted, dreamy, chemistry-obsessed boy in a family of accomplished physicians. His father was a general practitioner who made house calls, and his mother was one of the first female surgeons in England. His two eldest brothers were already studying medicine when he was in high school. Sacks dutifully followed his expected career path and was drawn to neurology when his third brother, Michael, developed schizophrenia. But after completing medical training, Sacks fled the homophobic confines of his nation and family—his mother had called him “an abomination.” Paul Theroux tells Burns that Sacks’s “great luck” was ending up in Los Angeles in 1960, where he found ample “guys, weights, drugs, and hospitals.” © 2020 American Association for the Advancement of Science

Keyword: Parkinsons
Link ID: 27477 - Posted: 09.19.2020

By Elizabeth Preston This is Panurgus banksianus, the large shaggy bee. It lives alone, burrowed into sandy grasslands across Europe. It prefers to feed on yellow-flowered members of the aster family. The large shaggy bee also has a very large brain. Just like mammals or birds, insect species of the same size may have different endowments inside their heads. Researchers have discovered some factors linked to brain size in back-boned animals. But in insects, the drivers of brain size have been more of a mystery. In a study published Wednesday in Proceedings of the Royal Society B, scientists scrutinized hundreds of bee brains for patterns. Bees with specialized diets seem to have larger brains, while social behavior appears unrelated to brain size. That means when it comes to insects, the rules that have guided brain evolution in other animals may not apply. “Most bee brains are smaller than a grain of rice,” said Elizabeth Tibbetts, an evolutionary biologist at the University of Michigan who was not involved in the research. But, she said, “Bees manage surprisingly complex behavior with tiny brains,” making the evolution of bee brains an especially interesting subject. Ferran Sayol, an evolutionary biologist at University College London, and his co-authors studied those tiny brains from 395 female bees belonging to 93 species from across the United States, Spain and the Netherlands. Researchers beheaded each insect and used forceps to remove its brain, a curled structure that’s widest in the center. “It reminds me a little bit of a croissant,” Dr. Sayol said. One pattern that emerged was a connection between brain size and how long each bee generation lasted. Bees that only go through one generation each year have larger brains, relative to their body size, than bees with multiple generations a year. © 2020 The New York Times Company

Keyword: Evolution; Learning & Memory
Link ID: 27476 - Posted: 09.16.2020

By John Horgan I interviewed psychologist Susan Blackmore 20 years ago while doing research for my book Rational Mysticism. Here, lightly edited, is my description of her: “Her hair was dyed orange, red, and yellow, dark-rooted, cut short as a boy’s, with sideburns plunging like daggers past each multi-ringed ear. Words spewed from her pell-mell, accompanied by equally vigorous hand signals and facial expressions. She was keen on onomatopoeic sound effects: Ahhhhh (to express her pleasure at finding other smart people when she entered Oxford); DUN da la DUN da la DUN (the galloping noise she heard as she sped down a tree-lined tunnel in her first out-of-body experience); Zzzzzzt (the sound of reality dissolving after her second toke of the psychedelic dimethyltryptamine). We were talking in the dining room of the inn where she was staying, and twice we had to move to a quieter spot when employees or patrons of the inn started talking near us. One side effect of her spiritual practice, she explained, is that she has a hard time ignoring stimuli. ‘I think it is one of the bad effects of practicing mindfulness. I'm so aware of everything all the time.’” Blackmore began her career as a parapsychologist, intent on finding evidence for astral projection and extrasensory perception. Her investigations transformed her into a materialist and Darwinian (one of her best-known books describes humans as “meme machines”) who doesn’t believe in ESP, God or free will. And yet she is a mystic, too, who explores consciousness via meditation and psychedelics. In other words, Blackmore pulls off the trick of being both a hard-nosed skeptic and an open-minded adventurer. What more can one ask of a mind scientist? Curious about how her thinking has evolved in our mind-boggling era, I e-mailed her a few questions. An edited transcript of the interview follows. © 2020 Scientific American

Keyword: Consciousness; Drug Abuse
Link ID: 27475 - Posted: 09.16.2020

By Lisa Sanders, M.D. The pain woke the 52-year-old physician from a dead sleep. It was as if all the muscles in his right leg, from those in the buttock down his thigh to the very bottom of his calf, were on fire. He shifted slightly to see if he could find a more comfortable position. There was a jag of pain, and he almost cried out. He glanced at the clock: 4 a.m. In just three hours he would have to get up. He had a full day of patients to see. Massage didn’t help. He couldn’t get comfortable lying flat, so finally he moved to the living room, to a recliner. Only then, and only by lying completely still, did he manage to get the pain to abate. He drifted off, but never for long. The searing pain in his leg and buttock slowly eased, and by the time his alarm went off, he could stand and walk — though his muscles still ached and he had to baby his right leg, causing a limp. Between patients, he arranged to see his own doctor. He’d had pain off and on in his buttocks, one side or the other, for more than a year. The pain was in the middle of each cheek and was worse when he was sitting and at the end of the day. Walking to and from his car on the way home was brutal. And then, as mysteriously as it came, it would disappear — only to come back a week or two later. When he first told his doctor about his pain, the exam didn’t show much. He was a little tender at the bottom of the bones you sit on, called the ischia. His doctor thought it was ischial bursitis. Between the tips of the ischia and the largest muscles of the buttocks, there are little pads called bursae. Sometimes these pads become inflamed. The man’s doctor recommended stretching exercises for the muscles around the bursae. He did them regularly, though he wasn’t sure they helped. The pain he had that night, though, was different, and a whole lot worse. Again, his doctor couldn’t find much. Maybe it was a kind of nerve pain, like sciatica, the patient suggested. The doctor agreed and ordered an M.R.I. to look for a pinched nerve. The result was normal. © 2020 The New York Times Company

Keyword: Pain & Touch; Neuroimmunology
Link ID: 27474 - Posted: 09.16.2020

David Cox Gérard Karsenty was a young scientist trying to make a name for himself in the early 1990s when he first stumbled upon a finding that would go on to transform our understanding of bone, and the role it plays in our body. Karsenty had become interested in osteocalcin, one of the most abundant proteins in bone. He suspected that it played a crucial role in bone remodelling – the process by which our bones continuously remove and create new tissue – which enables us to grow during childhood and adolescence, and also recover from injuries. Intending to study this, he conducted a genetic knockout experiment, removing the gene responsible for osteocalcin from mice. However to his dismay, his mutant mice did not appear to have any obvious bone defects at all. “For him, it was initially a total failure,” says Mathieu Ferron, a former colleague of Karsenty who now heads a research lab studying bone biology at IRCM in Montreal. “In those days it was super-expensive to do modification in the mouse genome.” But then Karsenty noticed something unexpected. While their bones had developed normally, the mice appeared to be both noticeably fat and cognitively impaired. “Mice that don’t have osteocalcin have increased circulating glucose, and they tend to look a bit stupid,” says Ferron. “It may sound silly to say this, but they don’t learn very well, they appear kind of depressed. But it took Karsenty and his team some time to understand how a protein in bone could be affecting these functions. They were initially a bit surprised and terrified as it didn’t really make any sense to them.” © 2020 Read It Later, Inc.

Keyword: Hormones & Behavior; Obesity
Link ID: 27473 - Posted: 09.16.2020

By Priyanka Runwal Acorn woodpeckers are renowned food hoarders. Every fall they stash as many as thousands of acorns in holes drilled into dead tree stumps in preparation for winter. Guarding these “granary trees” against acorn theft is a fierce, familial affair. But all hell breaks loose when there are deaths in a family and newly vacant spots in prime habitat are up for grabs. The news travels fast. Nearby woodpecker groups rush to the site and fight long, gory battles until one collective wins, according to a study published Monday in Current Biology. These wars also draw woodpecker audiences, the researchers reported, who leave their own territories unattended, demonstrating the immense investment and risks the birds are willing to take in pursuit of better breeding opportunities and intelligence gathering. “I think these power struggles are major events in the birds’ social calendars,” said Sahas Barve, an avian biologist at the Smithsonian National Museum of Natural History and lead author of the study. “They’re definitely trying to get social information out of it.” Acorn woodpecker societies are complex. Each family consists of up to seven adult males, often brothers, which breed with one to three females, often sisters but unrelated to the males. They live with nest helpers who are typically their offspring from previous years. Together they defend 15-acre territories, on average, encompassing one or more granaries in the oak forests along coastal Oregon down into Mexico. The helpers don’t breed, but stick around for five to six years to help raise their half-siblings until these babysitters can find a new territory to start their own families. “It’s all about biding your time and gaining indirect fitness,” Dr. Barve said. “But it’s never as good as reproducing directly.” © 2020 The New York Times Company

Keyword: Aggression; Evolution
Link ID: 27472 - Posted: 09.14.2020

By Elizabeth Landau At dinnertime, 10-year-old Clive Rodgers used to wrap his arms around his plate because he was afraid of germs at the table. “I was really scared, and if somebody tried to move my arm, I would, like, get really angry and stuff,” says Clive, who lives in San Diego with his parents and two younger siblings. Clive is just one of many young people who have struggled with obsessive-compulsive disorder. OCD affects about 1 in every 200 children and teenagers, which is similar to the prevalence of diabetes in this age group. The hallmarks of OCD are intrusive, unwanted thoughts and repetitive behaviors in response to those thoughts, a cycle that may cause significant anxiety and hamper daily activities. As the coronavirus pandemic rages on, it’s a tough time for any kid who has to stay home all day, studying remotely instead of going to school, unable to enjoy normal social activity with friends. Such stressors are making OCD symptoms worse in some children, even those who didn’t specifically fear germs before, doctors say. Andy Rodgers and his son, Clive, of in San Diego. Clive is just one of many youths who has struggled with obsessive-compulsive disorder. OCD affects about 1 in every 200 children and teenagers, which is similar to the prevalence of diabetes in this age group. “Their rituals and obsessions are just worse because their general mental health is worse,” said Suzan Song, director of the Division of Child/Adolescent & Family Psychiatry at George Washington University. Fears of contamination and illness are generally common among people with OCD, but usually their concerns are not in line with likely threats, said Joseph McGuire, assistant professor of psychiatry and behavioral sciences at Johns Hopkins Medicine. With the coronavirus, which causes the disease covid-19, there is actual danger present. He is seeing a “rekindling” of symptoms in many patients who received treatment in the past, and need a refresher.

Keyword: OCD - Obsessive Compulsive Disorder; Stress
Link ID: 27471 - Posted: 09.14.2020

By Linda Searing If you’re obese, losing just 5 percent of your weight starts you on the path to better health, but new research finds that losing 13 percent of your weight may make a good-size dent in your chances of developing several unhealthy conditions. For instance, the odds of developing Type 2 diabetes were at least 42 percent lower among obese people who lost that much weight than for those who did not lose weight, according to a report from the European and International Congress on Obesity. The research was based on eight years of data on 552,953 middle-aged adults who were obese and intentionally lost weight (meaning their weight loss did not occur because of an illness). Besides the diabetes effect, losing 13 percent of their weight also made people 25 percent less likely to develop high blood pressure or sleep apnea, and it correlated to a 22 percent risk reduction for high cholesterol and a 20 percent lower risk for osteoarthritis. Obesity, defined as excessive fat accumulation that presents a risk to health, is often determined by a person’s body mass index (BMI), a calculation of body fatness based on weight and height. The simplest way to figure your BMI is to plug your height and weight into an online calculator. A BMI of 30 or above is considered obese. Treatment for obesity usually starts with a modest weight-loss goal of 5 to 10 percent (10 to 20 pounds for someone weighing 200) and includes a change in eating habits and an increase in physical activity.

Keyword: Obesity
Link ID: 27470 - Posted: 09.14.2020

By Apoorva Mandavilli The coronavirus targets the lungs foremost, but also the kidneys, liver and blood vessels. Still, about half of patients report neurological symptoms, including headaches, confusion and delirium, suggesting the virus may also attack the brain. A new study offers the first clear evidence that, in some people, the coronavirus invades brain cells, hijacking them to make copies of itself. The virus also seems to suck up all of the oxygen nearby, starving neighboring cells to death. It’s unclear how the virus gets to the brain or how often it sets off this trail of destruction. Infection of the brain is likely to be rare, but some people may be susceptible because of their genetic backgrounds, a high viral load or other reasons. “If the brain does become infected, it could have a lethal consequence,” said Akiko Iwasaki, an immunologist at Yale University who led the work. The study was posted online on Wednesday and has not yet been vetted by experts for publication. But several researchers said it was careful and elegant, showing in multiple ways that the virus can infect brain cells. Scientists have had to rely on brain imaging and patient symptoms to infer effects on the brain, but “we hadn’t really seen much evidence that the virus can infect the brain, even though we knew it was a potential possibility,” said Dr. Michael Zandi, consultant neurologist at the National Hospital for Neurology and Neurosurgery in Britain. “This data just provides a little bit more evidence that it certainly can.” Dr. Zandi and his colleagues published research in July showing that some patients with Covid-19, the illness caused by the coronavirus, develop serious neurological complications, including nerve damage. © 2020 The New York Times Company

Keyword: Neuroimmunology; Stroke
Link ID: 27469 - Posted: 09.12.2020

By John Horgan It is a central dilemma of human life—more urgent, arguably, than the inevitability of suffering and death. I have been brooding and ranting to my students about it for years. It surely troubles us more than ever during this plague-ridden era. Philosophers call it the problem of other minds. I prefer to call it the solipsism problem. Solipsism, technically, is an extreme form of skepticism, at once utterly nuts and irrefutable. It holds that you are the only conscious being in existence. The cosmos sprang into existence when you became sentient, and it will vanish when you die. As crazy as this proposition seems, it rests on a brute fact: each of us is sealed in an impermeable prison cell of subjective awareness. Even our most intimate exchanges might as well be carried out via Zoom. You experience your own mind every waking second, but you can only infer the existence of other minds through indirect means. Other people seem to possess conscious perceptions, emotions, memories, intentions, just as you do, but you can’t be sure they do. You can guess how the world looks to me, based on my behavior and utterances, including these words you are reading, but you have no first-hand access to my inner life. For all you know, I might be a mindless bot. Natural selection instilled in us the capacity for a so-called theory of mind—a talent for intuiting others’ emotions and intentions. But we have a countertendency to deceive each other, and to fear we are being deceived. The ultimate deception would be pretending you’re conscious when you’re not. The solipsism problem thwarts efforts to explain consciousness. Scientists and philosophers have proposed countless contradictory hypotheses about what consciousness is and how it arises. Panpsychists contend that all creatures and even inanimate matter—even a single proton!—possess consciousness. Hard-core materialists insist, conversely (and perversely), that not even humans are all that conscious. © 2020 Scientific American

Keyword: Consciousness
Link ID: 27468 - Posted: 09.12.2020

Zeeya Merali Discovering the “on-and-off switch” for good parenting in male and female mouse brains has earned Catherine Dulac, a molecular biologist at Harvard University in Cambridge, Massachusetts, one of this year’s US$3-million Breakthrough prizes — the most lucrative awards in science and mathematics. Three other major prizes in biology, plus two in physics and one in mathematics, were also announced on 10 September, together with a number of smaller prizes. “Catherine Dulac has done amazing work that has really transformed the field,” says biologist Lauren O’Connell at Stanford University, California. Dulac’s team provided the first evidence that male and female mouse brains have the same neural circuitry associated with parenting, which is just triggered differently in each sex1. “It went against the dogma that for decades said that male and female brains are organized differently,” says O’Connell. Dulac says she was stunned to learn that she had won the award. “My brain froze, then I began to tear up,” she says, adding that it had been a long road to acceptance, because others had initially been sceptical of her work. In the 1990s, Dulac isolated the pheromone receptors in mice that govern sex-specific social behaviours. Virgin male mice usually attack other males and kill pups. But Dulac found that if their pheromone receptors were blocked, they would attempt to mate with both males and females, and virgin males would even care for pups. Pheromone-blind females, by contrast, would attempt to mount males. © 2020 Springer Nature Limited

Keyword: Sexual Behavior
Link ID: 27467 - Posted: 09.12.2020

by Angie Voyles Askham . Many problems associated with fragile X syndrome stem from a leak in mitochondria, organelles that act as the power stations of the cell, a new study suggests1. Stopping this leak eases some of the autism-like traits of mice that model the syndrome. “The paper is very solid,” says John Jay Gargus, director of the Center for Autism Research and Translation at the University of California, Irvine, who was not involved in the study. And because mitochondrial energy deficiency is seen in other forms of autism, the findings may be relevant beyond fragile X syndrome, Gargus says. Fragile X syndrome results from mutations in the FMR1 gene, which lead to a loss of the protein FMRP. Without FMRP, cells have immature dendritic spines — the bumps along a neuron’s arms that receive input from other neurons — and produce other proteins in excess. These differences are thought to contribute to the syndrome’s characteristic traits, such as developmental delay, intellectual disability and, often, autism. The new study shows that a leak in the mitochondrial membrane, possibly caused by the lack of FMRP, may drive the affected cells’ immaturity and excess protein production. The leak affects a cell’s metabolism, causing it to produce energy quickly but not efficiently, says lead researcher Elizabeth Jonas, professor of internal medicine and neuroscience at Yale University. All cells start out with mitochondrial leaks; the rapid energy production these leaks allow may be useful in early development. As typical cells mature and efficiency becomes more important than speed, however, they seem to close the leaks, Jonas says. Because cells with a fragile X mutation cannot close their leaks, they remain in an immature state. © 2020 Simons Foundation

Keyword: Development of the Brain
Link ID: 27466 - Posted: 09.12.2020

Primatologists observed that different groups of bonobos have different dietary preferences — indicating a form of "culture" among the animals. AILSA CHANG, HOST: Bonobos, like chimpanzees, are one of our closest living relatives. We share about 99% of our DNA. These endangered apes are covered in incredibly black hair. LIRAN SAMUNI: And what's very nice is that they have extremely pink lips, almost as if they put the lipstick on. SACHA PFEIFFER, HOST: That's Liran Samuni, a primatologist at Harvard University. Now her team has discovered that wild bonobos share more than just DNA with humans and chimps. They also appear to share our penchant for culture. SAMUNI: We already had some information about chimpanzees that they have the ability for culture. But it was always this kind of a puzzle about bonobos. CHANG: So for more than four years, the researchers tracked two bonobo groups in the Democratic Republic of Congo, documenting the apes' social interactions and what they hunted. And they found a striking dietary difference. SAMUNI: So we had one group which specialized on the hunting of a small antelope called duiker, while the other bonobo group specialized on the hunting of anomalure, which is a gliding rodent. PFEIFFER: Samuni says think about it in the context of humans. You might have two cultures living near or among each other, but one prefers chicken; the other prefers beef. CHANG: Samuni's colleague at Harvard Martin Surbeck says that's important because it shows that the two groups of bonobos have different preferences despite their overlapping range. © 2020 npr

Keyword: Evolution
Link ID: 27465 - Posted: 09.12.2020

By Katharine Q. Seelye Shere Hite, who startled the world in the 1970s with her groundbreaking reports on female sexuality and her conclusion that women did not need conventional sexual intercourse — or men, for that matter — to achieve sexual satisfaction, died on Wednesday at her home in London. She was 77. Her husband, Paul Sullivan, confirmed the death to The Guardian. The newspaper quoted a friend of Ms. Hite’s as saying that she had been treated for Alzheimer’s and Parkinson’s diseases. Her most famous work, “The Hite Report: A Nationwide Study of Female Sexuality” (1976), challenged societal and Freudian assumptions about how women achieved orgasm: It was not necessarily through intercourse, Ms. Hite wrote; women, she found, were quite capable of finding sexual pleasure on their own. However obvious her conclusions might seem today, they were seismic at the time and “sparked a revolution in the bedroom,” as Ms. magazine reported. For all the women who had faked orgasm during intercourse, the Hite Report helped awaken their sexual power and was seen as advancing the liberation of women that was rapidly underway. The book became an instant best seller and has been translated into a dozen languages. More than 48 million copies have been sold worldwide. What set the Hite Report apart from other studies were the questionnaires at the heart of it. More than 3,000 women were given anonymity in answering the queries, allowing them to write candidly and open-endedly — not in response to multiple-choice questions — about their experiences. “Researchers should stop telling women what they should feel sexually and start asking them what they do feel sexually,” Ms. Hite wrote. She described her questionnaires as a “giant rap session on paper.” In revelatory first-person testimonials, more than 70 percent of the respondents shattered the notion that women received sufficient stimulation during basic intercourse to reach climax. Rather, they said, they needed stimulation of the clitoris but often felt guilty and inadequate about it and were too embarrassed to tell their sexual partners. © 2020 The New York Times Company

Keyword: Sexual Behavior
Link ID: 27464 - Posted: 09.12.2020

By Veronique Greenwood Hummingbirds live a life of extremes. The flitting creatures famously have the fastest metabolisms among vertebrates, and to fuel their zippy lifestyle, they sometimes drink their own body weight in nectar each day. But the hummingbirds of the Andes in South America take that extreme lifestyle a step further. Not only must they work even harder to hover at altitude, but during chilly nights, they save energy by going into exceptionally deep torpor, a physiological state similar to hibernation in which their body temperature falls by as much as 50 degrees Fahrenheit. Then, as dawn approaches, they start to shiver, sending their temperatures rocketing back up to 96 degrees. It’s an intense process, says Andrew McKechnie, a professor of zoology at the University of Pretoria in South Africa. “You’ve got a bird perching on a branch, whose body temp might be 20 degrees Celsius,” or 68 Fahrenheit, he said. “And it’s cranking out the same amount of heat as when it is hovering in front of a flower.” Now, Dr. McKechnie and colleagues reported on Wednesday in Biology Letters that the body temperatures of Andean hummingbirds in torpor and the amount of time they spend in this suspended animation vary among species, with one particular set of species, particularly numerous in the Andes, tending to get colder and go longer than others. They also report one of the lowest body temperatures ever seen in hummingbirds: just under 38 degrees Fahrenheit. On a trip to the Andes about five years ago, Blair Wolf, a professor of biology at the University of New Mexico and an author of the new paper, and his colleagues captured 26 of the little birds for overnight observation. They measured the hummingbirds’ body temperatures as they roosted for the night and found that almost all of them entered torpor, showing a steep decline in temperature partway through the night. © 2020 The New York Times Company

Keyword: Sleep; Miscellaneous
Link ID: 27463 - Posted: 09.09.2020