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By Laura Sanders A century ago, science’s understanding of the brain was primitive, like astronomy before telescopes. Certain brain injuries were known to cause specific problems, like loss of speech or vision, but those findings offered a fuzzy view. Anatomists had identified nerve cells, or neurons, as key components of the brain and nervous system. But nobody knew how these cells collectively manage the brain’s sophisticated control of behavior, memory or emotions. And nobody knew how neurons communicate, or the intricacies of their connections. For that matter, the research field known as neuroscience — the science of the nervous system — did not exist, becoming known as such only in the 1960s. Over the last 100 years, brain scientists have built their telescopes. Powerful tools for peering inward have revealed cellular constellations. It’s likely that over 100 different kinds of brain cells communicate with dozens of distinct chemicals. A single neuron, scientists have discovered, can connect to tens of thousands of other cells. Yet neuroscience, though no longer in its infancy, is far from mature. Today, making sense of the brain’s vexing complexity is harder than ever. Advanced technologies and expanded computing capacity churn out torrents of information. “We have vastly more data … than we ever had before, period,” says Christof Koch, a neuroscientist at the Allen Institute in Seattle. Yet we still don’t have a satisfying explanation of how the brain operates. We may never understand brains in the way we understand rainbows, or black holes, or DNA. © Society for Science & the Public 2000–2021.

Keyword: Brain imaging; Learning & Memory
Link ID: 27722 - Posted: 03.06.2021

By Cathleen O’Grady People who take tiny amounts of LSD, “magic mushrooms,” and related drugs report a range of benefits, from more creativity to improved psychological well-being. But do these microdoses—typically less than 10% of the amount that causes a true psychedelic experience—actually benefit the mind? That’s been a hard question to answer. Placebo-controlled trials are tricky to pull off, because psychedelics are so tightly regulated. Now, researchers have come up with a creative workaround: They’ve enlisted microdosing enthusiasts to hide their drugs in gel capsules and mix them up with empty capsules. The upshot of this “self-blinding” study: Microdosing did lead to improvements in psychological well-being—but so did the placebo capsules. “The benefits are real,” says lead author Balázs Szigeti, a neuroscientist at Imperial College London. “But they are not caused by the pharmacological effects of microdosing.” The findings, however, are “the least interesting thing about this study,” says Noah Haber, a study design specialist at Stanford University. The “very, very clever” method of self-blinding pushes the boundaries of what can be investigated using randomized placebo controls, he says. Getting the new study off the ground wasn’t easy. Obtaining ethical approval to enroll psychedelic-taking volunteers was a “long and difficult process,” Szigeti says. And then he had to go out and find those volunteers, which he did by reaching out to microdosing communities, giving talks at psychedelic societies, and holding an “ask me anything” discussion on Reddit. Szigeti eventually garnered more than 1600 sign-ups, but once potential participants realized they’d have to procure their own psychedelics, interest ebbed, and only 246 ended up in the experiment. © 2021 American Association for the Advancement of Science.

Keyword: Depression; Drug Abuse
Link ID: 27721 - Posted: 03.06.2021

By Lisa Sanders, M.D. The voice on the phone was kind but firm: “You need to go to the emergency room. Now.” Her morning was going to be busy, replied the 68-year-old woman, and she didn’t feel well. Could she go later today or maybe tomorrow? No, said Dr. Benison Keung, her neurologist. She needed to go now; it was important. As she hung up the phone, tears blurred the woman’s already bad vision. She’d been worried for a while; now she was terrified. She was always healthy, until about four months earlier. It was a Saturday morning when she noticed that something seemed wrong with her right eye. She hurried to the bathroom mirror, where she saw that her right eyelid was drooping, covering the top half of the brown of her iris. On Monday morning, when she met her eye doctor, she was seeing double. Since then she’d had tests — so many tests — but received no answers. The woman walked to the bedroom where her 17-year-old granddaughter was still asleep. She woke her and asked for help getting dressed. Her hands were too weak for her to button her own clothes or tie her shoes. When she was completely dressed, she sent the girl to get her mother. She would need a ride to the hospital. She hadn’t been able to drive since she started seeing double. The events of the past few months had left the woman exhausted. First, she had seen her eye doctor. He took one look at her and told her that she had what’s called a third-nerve palsy. The muscles of the face and neck, he explained, are controlled by nerves that line up at the top of the spine. The nerve that controlled the eyelid, called the oculomotor nerve, was the third in this column. But he didn’t know what was affecting it or how to fix the problem. She needed to see a neuro-ophthalmologist, a doctor who specialized in the nerves that control the eyes. © 2021 The New York Times Company

Keyword: Movement Disorders; Neuroimmunology
Link ID: 27720 - Posted: 03.06.2021

By Erin Garcia de Jesus A whiff of catnip can make mosquitoes buzz off, and now researchers know why. The active component of catnip (Nepeta cataria) repels insects by triggering a chemical receptor that spurs sensations such as pain or itch, researchers report March 4 in Current Biology. The sensor, dubbed TRPA1, is common in animals — from flatworms to people — and responds to environmental irritants such as cold, heat, wasabi and tear gas. When irritants come into contact with TRPA1, the reaction can make people cough or an insect flee. Catnip’s repellent effect on insects — and its euphoric effect on felines — has been documented for millennia. Studies have shown that catnip may be as effective as the widely used synthetic repellent diethyl-m-toluamide, or DEET (SN: 9/5/01). But it was unknown how the plant repelled insects. So researchers exposed mosquitoes and fruit flies to catnip and monitored the insects’ behavior. Fruit flies were less likely to lay eggs on the side of a petri dish that was treated with catnip or its active component, nepetalactone. Mosquitoes were also less likely to take blood from a human hand coated with catnip. Insects that had been genetically modified to lack TRPA1, however, had no aversion to the plant. That behavior — coupled with experiments in lab-grown cells that show catnip activates TRPA1 — suggests that insect TRPA1 senses catnip as an irritant. Puzzling out how the plant deters insects could help researchers design potent repellents that may be easier to obtain in developing countries hit hard by mosquito-borne diseases. “Oil extracted from the plant or the plant itself could be a great starting point,” says study coauthor Marco Gallio, a neuroscientist at Northwestern University in Evanston, Ill. © Society for Science & the Public 2000–2021

Keyword: Pain & Touch; Evolution
Link ID: 27719 - Posted: 03.06.2021

By Veronique Greenwood Sign up for Science Times: Get stories that capture the wonders of nature, the cosmos and the human body. In the warm, fetid environs of a compost heap, tiny roundworms feast on bacteria. But some of these microbes produce toxins, and the worms avoid them. In the lab, scientists curious about how the roundworms can tell what’s dinner and what’s dangerous often put them on top of mats of various bacteria to see if they wriggle away. One microbe species, Pseudomonas aeruginosa, reliably sends them scurrying. But how do the worms, common lab animals of the species Caenorhabditis elegans, know to do this? Dipon Ghosh, then a graduate student in cellular and molecular physiology at Yale University, wondered if it was because they could sense the toxins produced by the bacteria. Or might it have something to do with the fact that mats of P. aeruginosa are a brilliant shade of blue? Given that roundworms do not have eyes, cells that obviously detect light or even any of the known genes for light-sensitive proteins, this seemed a bit far-fetched. It wasn’t difficult to set up an experiment to test the hypothesis, though: Dr. Ghosh, who is now a postdoctoral researcher at the Massachusetts Institute of Technology, put some worms on patches of P. aeruginosa. Then he turned the lights off. To the surprise of his adviser, Michael Nitabach, the worms’ flight from the bacteria was significantly slower in the dark, as though not being able to see kept the roundworms from realizing they were in danger. “When he showed me the results of the first experiments, I was shocked,” said Dr. Nitabach, who studies the molecular basis of neural circuits that guide behavior at Yale School of Medicine. In a series of follow-up experiments detailed in a paper published Thursday in Science, Dr. Ghosh, Dr. Nitabach and their colleagues establish that some roundworms respond clearly to that distinctive pigment, perceiving it — and fleeing from it — without the benefit of any known visual system. © 2021 The New York Times Company

Keyword: Vision; Evolution
Link ID: 27718 - Posted: 03.06.2021

Linda Geddes Four scientists who discovered a key mechanism that causes migraines, paving the way for new preventive treatments, have won the largest prize for neuroscience in the world, sharing £1.1m. The Lundbeck Foundation in Denmark announced on Thursday that the British researcher Peter Goadsby, Michael Moskowitz of the US, Lars Edvinsson of Sweden and Jes Olesen of Denmark had won the Brain prize. Speaking at a press briefing ahead of the announcement, Goadsby, a professor of neurology at King’s College London, said: “I’m excited that migraine research is getting this award and that migraine – this disabling problem that is a brain disorder – is being recognised in an appropriate way.” Formally known as the Grete Lundbeck European brain research prize, the annual award recognises highly original and influential advances in any area of brain research. The award ceremony will take place in Copenhagen on 25 October, where the prize will be presented by Crown Prince Frederik of Denmark. The prize-winning research revolves around unpicking the neural basis of migraine, a crippling neurological condition characterised by episodes of throbbing head pain, as well as nausea, vomiting, dizziness, extreme sensitivity to sound, light, touch and smell. It affects about one in seven people globally and is about three times more common in women than men. In the UK, it is estimated that migraines result in the loss of 25m work or school days each year at an economic cost of £2.3bn. © 2021 Guardian News & Media Limited

Keyword: Pain & Touch
Link ID: 27717 - Posted: 03.06.2021

By Elizabeth Pennisi For a glimpse of the power of sexual selection, the dance of the golden-collared manakin is hard to beat. Each June in the rainforests of Panama, the sparrow-size male birds gather to fluff their brilliant yellow throats, lift their wings, and clap them together in rapid fire, up to 60 times a second. When a female favors a male with her attention, he follows up with acrobatic leaps, more wing snaps, and perhaps a split-second, twisting backflip. “If manakins were human, they would be among the greatest artists, athletes, and socialites in our society,” says Ignacio Moore, an integrative organismal biologist at Virginia Polytechnic Institute and State University. As biologists have understood since Charles Darwin, such exhibitionism evolves when females choose to mate with males that have the most extravagant appearances and displays—a proxy for fitness. And now, by studying the genomes of the golden-collared manakin (Manacus vitellinus) and its relatives, researchers are exploring the genes that drive these elaborate behaviors and traits. Last month at the virtual meeting of the Society for Integrative and Comparative Biology, Moore and other researchers introduced four manakin genomes, adding to two already published, and singled out genes at work in the birds’ muscles and brains that may make the displays possible. © 2021 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Evolution
Link ID: 27716 - Posted: 03.06.2021

By Jake Buehler You might be able to do a mean celebrity impression or two, but can you imitate an entire film’s cast at the same time? A male superb lyrebird (Menura novaehollandiae) can, well almost. During courtship and even while mating, the birds pull off a similar feat, mimicking the calls and wingbeat noises of many bird species at once, a new study shows. The lyrebirds appear to be attempting to recreate the specific ecological soundscape associated with the arrival of a predator, researchers report February 25 in Current Biology. Why lyrebirds do this isn’t yet clear, but the finding is the first time that an individual bird has been observed mimicking the sounds of multiple bird species simultaneously. The uncanny acoustic imitation of multispecies flocks adds a layer of complexity to the male lyrebird’s courtship song yet unseen in birds and raises questions about why its remarkable vocal mimicry skills, which include sounds like chainsaws and camera shutters, evolved in the first place. Superb lyrebirds — native to forested parts of southeastern Australia — have a flair for theatrics. The males have exceptionally long, showy tail feathers that are shaken extensively in elaborate mating dances (SN: 6/6/13). The musical accompaniment to the dance is predominantly a medley of greatest hits of the songs of other bird species, the function of which behavioral ecologist Anastasia Dalziell was studying via audio and video recordings of the rituals.

Keyword: Sexual Behavior; Animal Communication
Link ID: 27715 - Posted: 02.28.2021

By Matt Richtel Texas has one of the most restrictive medical marijuana laws in the country, with sales allowed only by prescription for a handful of conditions. That hasn’t stopped Lukas Gilkey, chief executive of Hometown Hero CBD, based in Austin, Texas. His company sells joints, blunts, gummy bears, vaping devices and tinctures that offer a recreational high. In fact, business is booming online as well, where he sells to many people in other states with strict marijuana laws. But Mr. Gilkey says that he is no outlaw, and that he’s not selling marijuana, just a close relation. He’s offering products with a chemical compound — Delta-8-THC — extracted from hemp. It is only slightly chemically different from Delta 9, which is the main psychoactive ingredient in marijuana. And that small distinction, it turns out, may make a big difference in the eyes of the law. Under federal law, psychoactive Delta 9 is explicitly outlawed. But Delta-8-THC from hemp is not, a loophole that some entrepreneurs say allows them to sell it in many states where hemp possession is legal. The number of customers “coming into Delta 8 is staggering,” Mr. Gilkey said. “You have a drug that essentially gets you high, but is fully legal,” he added. “The whole thing is comical.” The rise of Delta 8 is a case study in how industrious cannabis entrepreneurs are pulling apart hemp and marijuana to create myriad new product lines with different marketing angles. They are building brands from a variety of potencies, flavors and strains of THC, the intoxicating substance in cannabis, and of CBD, the nonintoxicating compound that is often sold as a health product. With Delta 8, entrepreneurs also believe they have found a way to take advantage of the country’s fractured and convoluted laws on recreational marijuana use. It’s not quite that simple, though. Federal agencies, including the Drug Enforcement Administration, are still considering their options for enforcement and regulation. © 2021 The New York Times Company

Keyword: Drug Abuse
Link ID: 27714 - Posted: 02.28.2021

By Elizabeth Anne Brown Forget the soul — it turns out the eyes may be the best window to the brain. Changes to the retina may foreshadow Alzheimer’s and Parkinson’s diseases, and researchers say a picture of your eye could assess your future risk of neurodegenerative disease. Pinched off from the brain during embryonic development, the retina contains layers of neurons that seem to experience neurodegenerative disease along with their cousins inside the skull. The key difference is that these retinal neurons, right against the jellylike vitreous of the eyeball, live and die where scientists can see them. Early detection “is sort of the holy grail,” said Ron Petersen, director of Mayo Clinic’s Alzheimer’s Disease Research Center and the Mayo Clinic Study of Aging. By the time a patient complains of memory problems or tremors, the machinery of neurodegenerative disease has been at work probably for years or decades. Experts liken it to a cancer that only manifests symptoms at Stage 3 or 4. When patients begin to feel neurodegenerative disease’s impact on their daily life, it’s almost too late for treatment. Catching the warning signs of neurodegenerative disease earlier could give patients more time to plan for the future — whether that’s making caregiving arrangements, spending more time with family or writing the Great American novel. In the longer term, researchers hope the ability to notice brain changes before symptoms begin could eventually lead to early treatments more successful at slowing or stopping the progress of Parkinson’s and Alzheimer’s, since no such treatment is currently available. The hope is that “the sooner we intervene, the better we will be” at preventing cognitive impairment, Petersen said © 1996-2021 The Washington Post

Keyword: Alzheimers; Parkinsons
Link ID: 27713 - Posted: 02.28.2021

By Kim Tingley The brain is an electrical organ. Everything that goes on in there is a result of millivolts zipping from one neuron to another in particular patterns. This raises the tantalizing possibility that, should we ever decode those patterns, we could electrically adjust them to treat neurological dysfunction — from Alzheimer’s to schizophrenia — or even optimize desirable qualities like intelligence and resilience. Of course, the brain is so complex, and so difficult to access, that this is much easier to imagine than to do. A pair of studies published in January in the journal Nature Medicine, however, demonstrate that electrical stimulation can address obsessive-compulsive urges and symptoms of depression with surprising speed and precision. Mapping participants’ brain activity when they experienced certain sensations allowed researchers to personalize the stimulation and modify moods and habits far more directly than is possible through therapy or medication. The results also showed the degree to which symptoms that we tend to categorize as a single disorder — depression, for example — may involve electrical processes that are unique to each person. In the first study, a team from the University of California, San Francisco, surgically implanted electrodes in the brain of a woman whose severe depression had proved resistant to other treatments. For 10 days, they delivered pulses through the electrodes to different areas of the brain at various frequencies and had the patient record her level of depression, anxiety and energy on an iPad. The impact of certain pulses was significant and nuanced. “Within a minute, she would say, ‘I feel like I’m reading a good book,’” says Katherine W. Scangos, a psychiatrist and the study’s lead author. The patient described the effect of another pulse as “less cobwebs and cotton.” © 2021 The New York Times Company

Keyword: Depression
Link ID: 27712 - Posted: 02.28.2021

by Charles Q. Choi Blood levels of proteins associated with the autism-linked gene PTEN could influence the course of the condition, according to a new study. Tests measuring these molecules could also help clinicians diagnose autism and other neurological conditions, and chart their trajectories, the researchers say. “We might be able to make useful clinical predictions about outcomes that can help to tailor interventions earlier and to help patients and families plan for what is needed,” says lead investigator Thomas Frazier, professor of psychology at John Carroll University in University Heights, Ohio. The PTEN gene encodes a protein that suppresses tumors and also influences the connections between neurons. Mutations in PTEN are linked not only to benign tumors and several types of cancer, but also to autism and macrocephaly, or an unusually large head. Much remains unknown, however, about why PTEN mutations can affect people with and without autism differently. For example, PTEN mutations are often associated with impaired mental function in autistic people but not as often in non-autistic people, whose traits can vary widely. In the new study, Frazier and his colleagues examined how the mutations affect blood levels of not just PTEN protein, but also the proteins it interacts with. Molecular links: The team assessed the blood levels of various proteins — as well as intelligence quotient (IQ) and other factors related to mental function — in 25 autistic and 16 non-autistic participants with PTEN mutations and macrocephaly, all about 9 years old on average. The researchers also examined 20 participants, about 14 years old on average, with autism, macrocephaly and no PTEN mutations. © 2021 Simons Foundation

Keyword: Autism; Genes & Behavior
Link ID: 27711 - Posted: 02.28.2021

By Andreas von Bubnoff The world is getting fatter. More than 40 percent of U.S. adults are obese — almost three times more than in 1980. One reason for this weight gain is Americans are consuming more: National figures suggest an increase of about 200 daily calories between the early 1970s and 2010. Another is more snacking. In 2010, U.S. adults ate about 20 percent more of their daily calories as snacks than they did 50 years ago. But there is more to rising obesity rates than endless grazing. What also matters is timing, some experts believe. We eat when we shouldn’t, and don’t give our bodies a long enough break in between. We didn’t evolve to eat day and night, says neuroscientist Dominic D’Agostino of the University of South Florida. Until the dawn of agriculture about 12,000 years ago, we subsisted on hunting and gathering and often had to perform those activities with empty bellies. “We are hard-wired,” D’Agostino says, “to undergo periodic intermittent fasting.” What’s more, people are now eating at times of the day when historically they would have been asleep, says Satchin Panda, a circadian biologist at the Salk Institute for Biological Studies in La Jolla, Calif., who co-wrote an overview on the timing of eating in the 2019 Annual Review of Nutrition. For thousands of years, he says, our nightly fast probably started much earlier than in these times of late-night television. Although the research is still mixed, the timing of eating seems to matter for body weight and health. Studies suggest significant potential benefits from fasting every other day or so — or, on a daily basis, eating only when we would normally be awake, within a window of 12 hours or fewer — a practice known as time-restricted eating. © 1996-2021 The Washington Post

Keyword: Obesity
Link ID: 27710 - Posted: 02.28.2021

By Tom Bartlett The stimulant hexedrone — known more commonly as “bath salts” — is the kind of drug Carl Hart believes would be ideal to take right before a hellish academic reception or departmental holiday party. He’ll do cocaine and ecstasy from time to time and is a fan of the opioids oxycodone and morphine for the “pleasurable calmness” they induce. But after a long day, there are few things that Hart, a neuroscientist and psychology professor at Columbia University, enjoys more than a few lines of heroin by the fireplace. Hart has long pushed back against what he sees as the demonization of certain drugs and those who take them, particularly Black users, who are incarcerated at higher rates than white users. He has questioned the prevailing opinion that methamphetamine interferes with cognition and presented findings that suggest marijuana has minimal impact on the working memory of regular smokers. In his 2013 memoir, High Price: A Neuroscientist’s Journey of Self-Discovery That Challenges Everything You Know About Drugs and Society, Hart makes the case for decriminalizing narcotics and argues that “we’re too afraid of these drugs and of what we think they do.” In a 2014 talk at the TEDMed conference, he argued that “science should be driving our drug policy and our drug education, even if that makes you and me uncomfortable.” In his new book, Drug Use for Grown-Ups: Chasing Liberty in the Land of Fear, the former chairman of Columbia’s psychology department goes a step further, revealing that he has used — and continues to use — a number of illegal drugs. In fact, Hart recently said on a podcast that he was on methamphetamine when he delivered that TEDMed talk and that he’s given some of his best interviews the day after using heroin. Hart, who is 54, tried heroin for the first time in his 40s and has used it regularly — and responsibly, he contends — for years. “I am an unapologetic drug user,” he writes. “I take drugs as part of my pursuit of happiness, and they work. I am a happier and better person because of them.” He is not, he writes, an addict, and his book is not about addiction. Hart says that his stressful recent stint as department chairman was more damaging to his health than any substance he has ingested. © 2021 The Chronicle of Higher Education

Keyword: Drug Abuse
Link ID: 27709 - Posted: 02.28.2021

By Susan Milius Grown-up giraffes just aren’t huggy, cuddling, demonstrative animals. So it took identity-recognition software grinding through five years of data to reveal that female social life matters to survival. The more gregarious adult female giraffes in northern Tanzania’s Tarangire ecosystem tend to live longer, concludes wildlife biologist Monica Bond of the University of Zurich. Females that typically hung around at least three others of their kind, were more likely to outlive those with fewer routine companions, Bond and colleagues report February 10 in Proceedings of the Royal Society B. In published science, the idea that giraffes even have social lives isn’t much more than a decade old, Bond says. (For the time being, Bond still treats giraffes as one species, Giraffa camelopardalis, until there’s more agreement on how many species there are.) Adult males spend most of their time in solitary searches for females willing to mate, but females often hang around in groups. Compared with bats clustering under a bridge or baboons grooming pals’ fur, even the most sociable female giraffes often look as if they just happen to be milling around feeding in the same shrubbery. These “loose” groups, as Bond describes them, don’t snuggle or groom each other. A group mostly just browses in the same vicinity, then may fray apart and reconfigure with different members in the fission-fusion pattern seen in many animals, such as dolphins. Yet closer looks have found that females, in their low-drama way, prefer certain neighbors and seem to avoid certain others. © Society for Science & the Public 2000–2021.

Keyword: Stress
Link ID: 27708 - Posted: 02.28.2021

By Linda Searing People who smoke even occasionally are more likely than nonsmokers to have a serious type of stroke caused by a ruptured blood vessel — 27 percent more likely if they smoke up to 20 packs a year, according to research published in the journal Stroke. The average American smoker, according to the Centers for Disease Control and Prevention, smokes 14 cigarettes daily, which means about 255 packs a year. The type of stroke examined by the researchers, known as a subarachnoid hemorrhage, occurs when a weakened blood vessel ruptures and bleeds into the space between a person’s brain and skull. Most often, this results from an aneurysm, an abnormal bulge in a blood vessel. A subarachnoid hemorrhage is not as common as an ischemic stroke, which is caused by a blood clot, but it also can lead to neurological problems or be life-threatening without immediate treatment to stop the bleeding. To focus on the effect that smoking may have on people’s risk for this type of stroke, the researchers analyzed data on 408,609 adults, about a third of whom smoked regularly. During the study period, 904 participants had a subarachnoid hemorrhage. The more people smoked, the greater their risk for this type of stroke, prompting the American Stroke Association to note that the findings “provide evidence for a causal link” between smoking and subarachnoid hemorrhage. washingtonpost.com © 1996-2021

Keyword: Drug Abuse; Stroke
Link ID: 27707 - Posted: 02.28.2021

By Anahad O’Connor Five years ago, a group of nutrition scientists studied what Americans eat and reached a striking conclusion: More than half of all the calories that the average American consumes comes from ultra-processed foods, which they defined as “industrial formulations” that combine large amounts of sugar, salt, oils, fats and other additives. Highly processed foods continue to dominate the American diet, despite being linked to obesity, heart disease, Type 2 diabetes and other health problems. They are cheap and convenient, and engineered to taste good. They are aggressively marketed by the food industry. But a growing number of scientists say another reason these foods are so heavily consumed is that for many people they are not just tempting but addictive, a notion that has sparked controversy among researchers. Recently, the American Journal of Clinical Nutrition explored the science behind food addiction and whether ultra-processed foods might be contributing to overeating and obesity. It featured a debate between two of the leading experts on the subject, Ashley Gearhardt, associate professor in the psychology department at the University of Michigan, and Dr. Johannes Hebebrand, head of the department of child and adolescent psychiatry, psychosomatics and psychotherapy at the University of Duisburg-Essen in Germany. Dr. Gearhardt, a clinical psychologist, helped develop the Yale Food Addiction Scale, a survey that is used to determine whether a person shows signs of addictive behavior toward food. In one study involving more than 500 people, she and her colleagues found that certain foods were especially likely to elicit “addictive-like” eating behaviors, such as intense cravings, a loss of control, and an inability to cut back despite experiencing harmful consequences and a strong desire to stop eating them. At the top of the list were pizza, chocolate, potato chips, cookies, ice cream, French fries and cheeseburgers. © 2021 The New York Times Company

Keyword: Obesity; Drug Abuse
Link ID: 27706 - Posted: 02.23.2021

By Kelly Servick Put human stem cells in a lab dish with the right nutrients, and they’ll do their best to form a little brain. They’ll fail, but you’ll get an organoid: a semiorganized clump of cells. Organoids have become a powerful tool for studying brain development and disease, but researchers assumed these microscopic blobs only mirror a brain’s prenatal development—its earliest and simplest stages. A study today reveals that with enough time, organoid cells can take on some of the genetic signatures that brain cells display after birth, potentially expanding the range of disorders and developmental stages they can recreate. “Things that, before I saw this paper, I would have said you can’t do with organoids … actually, maybe you can,” says Madeline Lancaster, a developmental geneticist at the Medical Research Council’s Laboratory of Molecular Biology. For example, Lancaster wasn’t optimistic about using organoids to study schizophrenia, which is suspected to emerge in the brain after birth, once neural communication becomes more complex. But she now wonders whether cells from a person with this disorder—once “reprogrammed” to a primitive, stem cell state and coaxed to mature within a brain organoid—could reveal important cellular differences underlying the condition. Stanford University neurobiologist Sergiu Pașca has been making brain organoids for about 10 years, and his team has learned that some of these tissue blobs can thrive in a dish for years. In the new study, they teamed up with neurogeneticist Daniel Geschwind and colleagues at the University of California, Los Angeles (UCLA), to analyze how the blobs changed over their life spans. © 2021 American Association for the Advancement of Science.

Keyword: Development of the Brain
Link ID: 27705 - Posted: 02.23.2021

By Richard Sima Sign up for Science Times: Get stories that capture the wonders of nature, the cosmos and the human body. Though it is well-known for its many arms, the octopus does not seem to know where those eight appendages are most of the time. “In the octopus, you have no bones and no joints, and every point in its arm can go to every direction that you can think about,” said Nir Nesher, a senior lecturer in marine sciences at the Ruppin Academic Center in Israel. “So even one arm, it’s something like endless degrees of freedom.” So how does the octopus keep all those wiggly, sucker-covered limbs out of trouble? According to a study published this month in The Journal of Experimental Biology by Dr. Nesher and his colleagues, the octopus’s arms can sense and respond to light — even when the octopus cannot see it with the eyes on its head. This light-sensing ability may help the cephalopods keep their arms concealed from other animals that could mistake the tip of an arm for a marine worm or some other kind of meal. Itamar Katz, one of the study’s authors, first noticed the light-detecting powers while studying a different phenomenon: how light causes the octopus’s skin to change color. With Dr. Nesher and Tal Shomrat, another author, Mr. Katz saw that shining light on an arm caused the octopus to withdraw it, even when the creature was sleeping. Further experiments showed that the arms would avoid the light in situations when the octopus could not see it with its eyes. Even when the octopuses reached an arm out of a small opening on an opaque, covered aquarium for food, the arm would quickly retract when light was shined on it 84 percent of the time. This was a surprise, as though the octopus “can see the light through the arm, it can feel the light through the arm,” Dr. Nesher said. “They don’t need the eye for that.” ImageScientists suspect octopuses keep their arms concealed from other animals that could mistake the tip of an arm for a meal. Scientists suspect octopuses keep their arms concealed from other animals that could © 2021 The New York Times Company

Keyword: Vision; Evolution
Link ID: 27704 - Posted: 02.23.2021

By Sui-Lee Wee Mark Lewis was desperate to find monkeys. Millions of human lives, all over the world, were at stake. Mr. Lewis, the chief executive of Bioqual, was responsible for providing lab monkeys to pharmaceutical companies like Moderna and Johnson & Johnson, which needed the animals to develop their Covid-19 vaccines. But as the coronavirus swept across the United States last year, there were few of the specially bred monkeys to be found anywhere in the world. Unable to furnish scientists with monkeys, which can cost more than $10,000 each, about a dozen companies were left scrambling for research animals at the height of the pandemic. “We lost work because we couldn’t supply the animals in the time frame,” Mr. Lewis said. The world needs monkeys, whose DNA closely resembles that of humans, to develop Covid-19 vaccines. But a global shortage, resulting from the unexpected demand caused by the pandemic, has been exacerbated by a recent ban on the sale of wildlife from China, the leading supplier of the lab animals. The latest shortage has revived talk about creating a strategic monkey reserve in the United States, an emergency stockpile similar to those maintained by the government for oil and grain. As new variants of the coronavirus threaten to make the current batch of vaccines obsolete, scientists are racing to find new sources of monkeys, and the United States is reassessing its reliance on China, a rival with its own biotech ambitions. The pandemic has underscored how much China controls the supply of lifesaving goods, including masks and drugs, that the United States needs in a crisis. American scientists have searched private and government-funded facilities in Southeast Asia as well as Mauritius, a tiny island nation off southeast Africa, for stocks of their preferred test subjects, rhesus macaques and cynomolgus macaques, also known as long-tailed macaques. But no country can make up for what China previously supplied. Before the pandemic, China provided over 60 percent of the 33,818 primates, mostly cynomolgus macaques, imported into the United States in 2019, according to analyst estimates based on data from the Centers for Disease Control and Prevention. © 2021 The New York Times Company

Keyword: Animal Rights
Link ID: 27703 - Posted: 02.23.2021