By Aayushi Pratap In Rector, Pa., researchers have spotted one strange bird. This rose-breasted grosbeak has a pink breast spot and a pink “wing pit” and black feathers on its right wing — telltale shades of males. But on its left side, the songbird displays yellow and brown plumage, hues typical of females. Annie Lindsay had been out capturing and banding birds with identification tags with her colleagues at Powdermill Nature Reserve in Rector on September 24 when a teammate hailed her on her walkie-talkie to alert her of the bird’s discovery. Lindsay, who is banding program manager at Powdermill, immediately knew what she was looking at: a half-male, half-female creature known as a gynandromorph. “It was spectacular. This bird is in its nonbreeding [plumage], so in the spring when it’s in its breeding plumage, it’s going to be even more starkly male, female,” Lindsay says. The bird’s colors will become even more vibrant, and “the line between the male and female side will be even more obvious.” Gynandromorphs are found in many species of birds, insects and crustaceans such as crabs and lobsters. This bird is likely the result of an unusual event when two sperm fertilize an egg that has two nuclei instead of one. The egg can then develop male sex chromosomes on one side and female sex chromosomes on the other, ultimately leading to a bird with a testis and other male characteristics on one half of its body and an ovary and other female qualities on the other half. © Society for Science & the Public 2000–2020

Keyword: Sexual Behavior
Link ID: 27506 - Posted: 10.07.2020

By Macarena Carrizosa, Sophie Bushwick A new system called PiVR creates working artificial environments for small animals such as zebra fish larvae and fruit flies. Developers say the system’s affordability could help expand research into animal behavior. © 2020 Scientific American

Keyword: Development of the Brain; Vision
Link ID: 27505 - Posted: 10.07.2020

By Jake Buehler During the summer feeding season in high latitudes, male blue whales tend to sing at night. But shortly before migrating south to their breeding grounds, the whales switch up the timing and sing during the day, new research suggests. This is not the first time that scientists have observed whales singing at a particular time of day. But the finding appears to be the first instance of changes in these daily singing patterns throughout the yearly feeding and mating cycle, says William Oestreich, a biological oceanographer at Stanford University. In the North Pacific, blue whales (Balaenoptera musculus) spend summers off North America’s coast gorging on krill before traveling to the tropics to breed in winter. Data collected by an underwater microphone dropped into Monterey Bay in California to record the region’s soundscape for five years allowed Oestreich and his colleagues to eavesdrop on whales that visited the bay. When the team separated daytime and nighttime whale songs, it stumbled upon a surprising pattern: In the summer and early fall, most songs occurred at night, but as winter breeding season approached, singing switched mostly to the daytime. “This was a very striking signal to observe in such an enormous dataset,” says Oestreich. The instrument has been collecting audio since July 2015, relaying nearly 2 terabytes of data back to shore every month. The researchers also tagged 15 blue whales with instruments and from 2017 to 2019, recorded the whales’ movements, diving and feeding behavior, as well as their singing — nearly 4,000 songs’ worth. Whales that were feeding and hadn’t yet started migrating to the breeding grounds sang primarily at night — crooning about 10 songs per hour on average at night compared with three songs per hour in the day, or roughly three times as often. But those that had begun their southward trip sang mostly in the day, with the day-night proportions roughly reversed, the team reports October 1 in Current Biology. © Society for Science & the Public 2000–2020.

Keyword: Animal Communication; Animal Migration
Link ID: 27504 - Posted: 10.03.2020

by Angie Voyles Askham Autistic people share some brain structure differences with people who have other neuropsychiatric conditions, including schizophrenia and attention deficit hyperactivity disorder (ADHD), according to a massive new brain-imaging study1. These shared differences stem from the atypical development of one particular type of neuron, the findings suggest. The results provide “further evidence that our understanding of autism can really be advanced by explicitly studying autism in the context of other disorders,” says Armin Raznahan, chief of the Section on Developmental Neurogenomics at the U.S. National Institute of Mental Health in Bethesda, Maryland, who was not involved in the study. The researchers looked at brain scans from 28,321 people to identify structural changes associated with any of six conditions: autism, ADHD, bipolar disorder, major depressive disorder, obsessive-compulsive disorder and schizophrenia. The team found that the brains of people with these conditions differ from controls in a specific way: They have similar patterns of thickness across the cortex, the brain’s outer layer. The cortical regions with the biggest differences in thickness are typically rich in a particular type of excitatory neuron. “We were able to put our fingers on what might be behind that commonality,” says lead researcher Tomas Paus, professor of psychology and psychiatry at the University of Toronto in Canada. “That was very exciting.” The work combined data from 145 cohorts within the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) consortium, an international group of researchers who collect and analyze brain-scan data in a standardized way so that they can pool their results. © 2020 Simons Foundation

Keyword: Autism; Brain imaging
Link ID: 27503 - Posted: 10.03.2020

By Christa Lesté-Lasserre The bacteria that live in our bodies, particularly our guts, play key roles in immunity and development. But babies born by cesarean section don’t get the rich blend of microbes that come from a vaginal birth—microbes that may help prevent disorders such as asthma and allergies. Now, a study suggests feeding these infants a small amount of their mothers’ feces could “normalize” their gut microbiome—the ecosystem of bacteria, viruses, and fungi in the digestive system—and possibly give their immune systems a healthier start. Newborns’ guts are blank slates: Babies born vaginally get microbes from their mother’s perineum (the area around the vulva and anus), and those born by C-section get them from mom’s skin. Within just a few hours, the differences are stark. For example, Bacteroides and Bifidobacteria bacteria are abundant in the guts of babies born vaginally, but “almost absent in C-section babies,” says Willem de Vos, a microbiome scientist at the University of Helsinki. Because babies born by C-section have higher rates of immune-related disorders later in life, researchers think this early-life bacteria could “prime” the immune system during a critical development period. To lessen the damage, previous studies have “seeded” C-section babies with their mothers’ vaginal microbiota. But when those efforts didn’t seem to do the trick, de Vos and colleagues theorized that vaginally born babies might get their microbes from accidentally ingesting a smidgen of their mother’s stool during the birthing process. So they recruited 17 mothers preparing to give birth via C-section. Three weeks before the women were to give birth, their fecal samples were scanned for pathogens including group B Streptococcus and herpesvirus. © 2020 American Association for the Advancement of Science.

Keyword: Neuroimmunology
Link ID: 27502 - Posted: 10.03.2020

By Nicholas Bakalar Being overweight is linked to an increased risk for premature death, but which part of the body carries the added fat could make a big difference. Extra weight in some places may actually lower the risk. Researchers, writing in BMJ, reviewed 72 prospective studies that included more than two and a half million participants with data on body fat and mortality. They found that central adiposity — a large waist — was consistently associated with a higher risk of all-cause mortality. In pooled data from 50 studies, each four-inch increase in waist size was associated with an 11 percent increased relative risk for premature death. The association was significant after adjusting for smoking, physical activity and alcohol consumption. Waist size is an indicator of the amount of visceral fat, or fat stored in the abdomen around the internal organs. This kind of fat is associated with an increased risk for heart disease, Type 2 diabetes, cancer and Alzheimer’s disease. But increased fat in two places appears to be associated with a lower risk of death. Three studies showed that each two-inch increase in thigh circumference was associated with an 18 percent lower risk of all-cause mortality. In nine studies involving almost 300,000 participants, a four-inch increase in a woman’s hip circumference was associated with a 10 percent lower risk of death. “Thigh size is an indicator of the amount of muscle, which is protective,” said a co-author of the review, Tauseef Ahmad Khan, a postdoctoral fellow at the University of Toronto. “And hip fat is not visceral fat, but subcutaneous fat, which is considered beneficial.” © 2020 The New York Times Company

Keyword: Obesity
Link ID: 27501 - Posted: 10.03.2020

By Cara Giaimo Last year, Katie Goldin was walking in her Los Angeles neighborhood when she saw, in the middle of the sidewalk, two lizards interlocked. The male, flecked like a pebble and about a foot long, had his jaws fully around the slightly smaller female’s head. “He was tenderly clasping her neck in his mouth,” said Ms. Goldin, host of a podcast called “Creature Feature.” “She seemed like she was in a trance.” Even in a world absolutely full of bizarre reproductive strategies, southern alligator lizards are up there. The pair Ms. Goldin spotted were engaged in what’s known as “mate-holding,” a part of the copulatory process in which a male grips a female’s head in his mouth for hours or even days at a time. It’s not clear why the lizards do this. But recently, two research projects have looked into the animals’ ecology and anatomy to better understand where, when and how this strange behavior happens. By approaching the same subject from these very different vantage points, scientists can inform each other’s research, and get a clearer picture of what’s really going on. Spying on lizard sex, for science After Ms. Goldin saw the happy couple, she sent pictures to the Natural History Museum of Los Angeles County. Since 2015, the museum has put out a yearly call for photos and videos of alligator lizards getting it on, which it collects through emails, social media and the platform iNaturalist. The species is the most widespread reptile in Los Angeles. But because the city is a “jigsaw puzzle of private property,” it’s difficult to do traditional wildlife surveys, said Greg Pauly, the museum’s herpetology curator. There are only a handful of published accounts of the lizard’s mating behavior in the scientific literature. © 2020 The New York Times Company

Keyword: Sexual Behavior; Aggression
Link ID: 27500 - Posted: 09.30.2020

Paulina Villegas Texas Gov. Greg Abbott issued a disaster declaration in Brazoria County on Sunday after the discovery in the local water supply system of an amoeba that can cause a rare and deadly infection of the brain. “The state of Texas is taking swift action to respond to the situation and support the communities whose water systems have been impacted by this ameba,” Abbott (R) in a news release Sunday. “I urge Texans in Lake Jackson to follow the guidance of local officials and take the appropriate precautions to protect their health and safety as we work to restore safe tap water in the community.” The governor’s declaration follows an investigation of the death of 6-year-old Josiah McIntyre in Lake Jackson this month after he contracted the brain-eating microbe, which prompted local authorities and experts from the Centers for Disease Control and Prevention to test the water. The preliminary results came back Friday, showing that three out of 11 samples collected tested positive. One of the samples came from a hose bib at the boy’s home, Lake Jackson City Manager Modesto Mundo said, according to CBS News. The others came from a “splash pad” play fountain and a hydrant. “The notification to us at that time was that he had played at one of [the] play fountains and he may have also played with a water hose at the home,” Mundo said. On Friday night, the Brazosport Water Authority issued a do-not-use advisory for eight communities after confirmation of the presence of Naegleria fowleri, which destroys brain tissue, then causes swelling of the brain, known as amebic meningoencephalitis. It urged residents to not use the tap water for drinking and cooking. © 1996-2020 The Washington Post

Keyword: Miscellaneous
Link ID: 27499 - Posted: 09.30.2020

By Lisa Sanders, M.D. The waiter had barely put the plate in front of her when the 46-year-old woman felt the color drain from her face. She was in Fresno, Calif., on a work trip and had come to a restaurant to meet an old friend for dinner. But all of a sudden her stomach dropped — the way it might on a roller-coaster ride. A sudden coolness on her face told her she’d broken out in a sweat. She felt dizzy and a little confused. She saw the alarmed face of her friend and knew she looked as bad as she felt. She excused herself and carefully made her way to the bathroom. She sat in front of the vanity and supported her head on her arms. There was the now-familiar stabbing pain in her stomach. She wasn’t sure how long she stayed like that. Was it 10 minutes? 15? At last she felt as if she could get up. As she hurried to meet her friend at the entrance, she felt the contents of her stomach surging upward. She covered her mouth as vomit shot between her fingers. She lowered her head and bolted through the doorway, trying not to see the horrified faces of the diners. In the parking lot, the rush of stomach contents continued until she was completely empty. Exhausted, she sank into the seat of her friend’s car. She was too sick to go back to her hotel, her friend said. Instead the friend would take her to her house, until she felt better. The next thing the woman remembered was that she was sitting on the floor of her friend’s shower, hot water pounding her back. When she could, she crawled into bed. She slept until late the next morning. She thanked her friend, canceled her morning meetings and later that day headed home to Stockton, Calif. © 2020 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 27498 - Posted: 09.30.2020

By Lisa Grossman Clues from a chemical — Science News, October 3, 1970 An experimental drug’s effects on the sexual behavior of certain animals is arousing interest among investigators.… The drug, para-chlorophenylalanine … reduces the level of a naturally occurring neurochemical, serotonin, in the brain of rats, mice and dogs.… Little is known about how serotonin acts in the brain, and investigators quickly recognized that PCPA could be used to study this brain chemical. Update PCPA helped e­stablish serotonin’s role in regulating sexual desire, as well as sleep, appetite and mood. The chemical messenger has become key to one common class of antidepressant drugs called selective serotonin r­euptake inhibitors. Identified in 1974, SSRIs work by increasing the brain’s serotonin levels. But such drugs can hinder sexual desire. One SSRI that failed to relieve depression in humans found a second life as a treatment for sexual dysfunction. Approved by the U.S. Food and Drug Administration in 2015, this “little pink pill,” sold as Addyi, may boost sex drive in women by lowering serotonin in the brain’s reward centers. H.A. Croft. Understanding the role of serotonin in female hypoactive sexual desire disorder and treatment options. Journal of Sexual Medicine. Vol. 14, December 2017, p. 1575. Doi: 10.1016/j.jsxm.2017.10.068. © Society for Science & the Public 2000–2020.

Keyword: Depression; Sexual Behavior
Link ID: 27497 - Posted: 09.30.2020

Ian Sample Science editor Doctors believe they are closer to a treatment for multiple sclerosis after discovering a drug that repairs the coatings around nerves that are damaged by the disease. A clinical trial of the cancer drug bexarotene showed that it repaired the protective myelin sheaths that MS destroys. The loss of myelin causes a range of neurological problems including balance, vision and muscle disorders, and ultimately, disability. While bexarotene cannot be used as a treatment, because the side-effects are too serious, doctors behind the trial said the results showed “remyelination” was possible in humans, suggesting other drugs or drug combinations will halt MS. Advertisement “It’s disappointing that this is not the drug we’ll use, but it’s exciting that repair is achievable and it gives us great hope for another trial we hope to start this year,” said Prof Alasdair Coles, who led the research at the University of Cambridge. MS arises when the immune system mistakenly attacks the fatty myelin coating that wraps around nerves in the brain and spinal cord. Without the lipid-rich substance, signals travel more slowly along nerves, are disrupted, or fail to get through at all. About 100,000 people in the UK live with the condition. Funded by the MS Society, bexarotene was assessed in a phase 2a trial that used brain scans to monitor changes to damaged neurons in patients with relapsing MS. This is an early stage of the condition that precedes secondary progressive disease, where neurons die off and cause permanent disability. © 2020 Guardian News & Media Limited

Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 27496 - Posted: 09.28.2020

By Jane E. Brody Growing rates of obesity among Americans are clear evidence that even the best intentions and strongest motivations are often not enough to help seriously overweight people lose a significant amount of weight and, more important, keep it off. But for those who can overcome fears of surgery and perhaps do battle with recalcitrant insurers, there remains another very successful option that experts say is currently vastly underused. That option is bariatric surgery, an approach that is now simpler, safer and more effective than in its early days in the 1990s. “Only one-half of 1 percent of people eligible for bariatric surgery currently undergo it,” Dr. Anne P. Ehlers, a bariatric surgeon at the University of Michigan, told me. Bariatric surgery is generally considered a treatment option for people with a body mass index (B.M.I.) of 40 or more who failed to lose weight with diet and exercise alone. It is also recommended for those with lesser degrees of obesity — a B.M.I. of 30 to 35 — who have obesity-related medical conditions. The underuse of weight-loss surgery has been largely attributed to “the reluctance of the medical community and patients to accept surgery as a safe, effective and durable treatment of obesity,” other experts at the University of Michigan wrote in JAMA in 2018. They added that patients “may be reluctant to pursue surgical treatment because they may be judged by others for taking the easy way out and not having the willpower to diet and exercise.” © 2020 The New York Times Company

Keyword: Obesity
Link ID: 27495 - Posted: 09.28.2020

In an article published in Nature Genetics, researchers confirm that about 14% of all cases of cerebral palsy, a disabling brain disorder for which there are no cures, may be linked to a patient’s genes and suggest that many of those genes control how brain circuits become wired during early development. This conclusion is based on the largest genetic study of cerebral palsy ever conducted. The results led to recommended changes in the treatment of at least three patients, highlighting the importance of understanding the role genes play in the disorder. The work was largely funded by the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health. “Our results provide the strongest evidence to date that a significant portion of cerebral palsy cases can be linked to rare genetic mutations, and in doing so identified several key genetic pathways involved,” said Michael Kruer, M.D., a neurogeneticist at Phoenix Children’s Hospital and the University of Arizona College of Medicine - Phoenix and a senior author of the article. “We hope this will give patients living with cerebral palsy and their loved ones a better understanding of the disorder and doctors a clearer roadmap for diagnosing and treating them.” Cerebral palsy affects approximately one in 323 children(link is external) in the United States. Signs of the disorder appear early in childhood resulting in a wide range of permanently disabling problems with movement and posture, including spasticity, muscle weakness, and abnormal gait. Nearly 40% of patients need some assistance with walking. In addition, many patients may also suffer epileptic seizures, blindness, hearing and speech problems, scoliosis, and intellectual disabilities.

Keyword: Development of the Brain; Genes & Behavior
Link ID: 27494 - Posted: 09.28.2020

by Peter Hess / Some preterm babies who are later diagnosed with autism show increasing developmental delays during infancy, according to a new study1. This distinct pattern could help doctors identify autism in preterm babies and start them on therapies in infancy, says Li-Wen Chen, pediatric neurologist at National Cheng Kung University College of Medicine in Taiwan, who designed and conducted the study. About 7 percent of children born preterm are autistic, compared with 1 to 2 percent of children in the general population. Researchers cannot accurately predict which preterm babies are most likely to be later diagnosed with the condition, however. The new study tracked ‘very preterm’ babies — meaning those born more than 8 weeks prematurely and weighing 3.3 pounds or less — from birth to 5 years old. It shows that preterm autistic babies’ development deviates significantly from that of their non-autistic peers starting at 6 months of age. This split could flag preterm babies in need of behavioral interventions well before the typical age of an autism diagnosis, which is about 4 years in the United States. “This early trajectory work is really very valuable, because it means you shouldn’t be making predictions based on single observations,” says Neil Marlow, professor of neonatal medicine at University College London in the United Kingdom, who was not involved in the work. Autistic children who are born preterm score lower on measures of nonverbal behaviors important for social interactions than do autistic children who are born full-term, according to previous work by Chen’s team2. Those results also showed that autism traits are more similar among preterm children than among full-term children. © 2020 Simons Foundation

Keyword: Autism
Link ID: 27493 - Posted: 09.28.2020

The benefits of companionship for humans are well known, and they're not just confined to our mental health. Humans with strong social bonds with others live longer, healthier lives. Now a study looking at wild baboons in Africa has shown this is true for them as well. In particular, male baboons with non-sexual friendships with females live far longer than animals who lack these social bonds. Researchers have known for years that companionship is beneficial for the health and longevity of female baboons. But because of their social structure, male baboons are much harder to study over a long term than females. Female baboons stay with their birth troop for their entire lives, and so are easy to track and observe. Males, on the other hand, switch troops after they mature, and sometimes in adulthood as well, and so tracking them for their lifetime — which averages something like a decade and a half — can be a challenge. But a team led by Susan Alberts, a professor of biology and chair of the evolutionary anthropology department at Duke University, was able to master this problem. Friends with benefits Platonic friendship among baboons of the opposite sex is, it turns out, common. According to Alberts, male baboons will frequently form non-sexual friendship bonds with females and will protect them and their offspring from aggression within the troop and from predators. The benefits of this for the females are clear. What was less clear was the benefits of this kind of companionship for the males. The new study from Alberts and her team drew on data collected over many years from over 500 baboons at Amboseli National Park in Kenya to answer that question.. ©2020 CBC/Radio-Canada.

Keyword: Stress; Sexual Behavior
Link ID: 27492 - Posted: 09.28.2020

Jon Hamilton Mental illness can run in families. And Dr. Kafui Dzirasa grew up in one of these families. His close relatives include people with schizophrenia, bipolar disorder and depression. As a medical student, he learned about the ones who'd been committed to psychiatric hospitals or who "went missing" and were discovered in alleyways. Dzirasa decided to dedicate his career to "figuring out how to make science relevant to ultimately help my own family." He became a psychiatrist and researcher at Duke University and began to study the links between genes and brain disorders. Then Dzirasa realized something: "I was studying genes that were specifically related to illness in folks of European ancestry." His family had migrated from West Africa, which meant anything he discovered might not apply to them. Dzirasa also realized that people with his ancestry were missing not only from genetics research but from the entire field of brain science. "It was a really crushing moment for me," he says. So when a group in Baltimore asked Dzirasa to help do something about the problem, he said yes. The group is the African Ancestry Neuroscience Research Initiative. It's a partnership between community leaders and the Lieber Institute for Brain Development, an independent, nonprofit research organization on the medical campus of Johns Hopkins University. © 2020 npr

Keyword: Attention
Link ID: 27491 - Posted: 09.28.2020

Jon Henley Europe correspondent Four Covid-19 sniffer dogs have begun work at Helsinki airport in a state-funded pilot scheme that Finnish researchers hope will provide a cheap, fast and effective alternative method of testing people for the virus. A dog is capable of detecting the presence of the coronavirus within 10 seconds and the entire process takes less than a minute to complete, according to Anna Hielm-Björkman of the University of Helsinki, who is overseeing the trial. “It’s very promising,” said Hielm-Björkman. “If it works, it could prove a good screening method in other places” such as hospitals, care homes and at sporting and cultural events. After collecting their luggage, arriving international passengers are asked to dab their skin with a wipe. In a separate booth, the beaker containing the wipe is then placed next to others containing different control scents – and the dog starts sniffing. If it indicates it has detected the virus – usually by yelping, pawing or lying down – the passenger is advised to take a free standard polymerase chain reaction (PCR) test, using a nasal swab, to verify the dog’s verdict. In the university’s preliminary tests, dogs – which have been successfully used to detect diseases such as cancer and diabetes – were able to identify the virus with nearly 100% accuracy, even days before before a patient developed symptoms. Scientists are not yet sure what exactly it is that the dogs sniff when they detect the virus. A French study published in June concluded that there was “very high evidence” that the sweat odour of Covid-positive people was different to that of those who did not have the virus, and that dogs could detect that difference. Dogs are also able to identify Covid-19 from a much smaller molecular sample than PCR tests, Helsinki airport said, needing only 10-100 molecules to detect the presence of the virus compared with the 18m needed by laboratory equipment. © 2020 Guardian News & Media Limited

Keyword: Chemical Senses (Smell & Taste)
Link ID: 27490 - Posted: 09.25.2020

By Pam Belluck Annrene Rowe was getting ready to celebrate her 10th wedding anniversary this summer when she noticed a bald spot on her scalp. In the following days, her thick shoulder-length hair started falling out in clumps, bunching up in the shower drain. “I was crying hysterically,” said Mrs. Rowe, 67, of Anna Maria, Fla. Mrs. Rowe, who was hospitalized for 12 days in April with symptoms of the coronavirus, soon found strikingly similar stories in online groups of Covid-19 survivors. Many said that several months after contracting the virus, they began shedding startling amounts of hair. Doctors say they too are seeing many more patients with hair loss, a phenomenon they believe is indeed related to the coronavirus pandemic, affecting both people who had the virus and those who never became sick. In normal times, some people shed noticeable amounts of hair after a profoundly stressful experience such as an illness, major surgery or emotional trauma. Now, doctors say, many patients recovering from Covid-19 are experiencing hair loss — not from the virus itself, but from the physiological stress of fighting it off. Many people who never contracted the virus are also losing hair, because of emotional stress from job loss, financial strain, deaths of family members or other devastating developments stemming from the pandemic. “There’s many, many stresses in many ways surrounding this pandemic, and we’re still seeing hair loss because a lot of the stress hasn’t gone away,” said Dr. Shilpi Khetarpal, an associate professor of dermatology at the Cleveland Clinic. Before the pandemic, there were weeks when Dr. Khetarpal didn’t see a single patient with hair loss of this type. Now, she said, about 20 such patients a week come in. One was a woman having difficulty home-schooling two young children while also working from home. Another was a second-grade teacher anxiously trying to ensure that all her students had computers and internet access for online instruction. © 2020 The New York Times Company

Keyword: Stress
Link ID: 27489 - Posted: 09.25.2020

Jordana Cepelewicz Our sense of time may be the scaffolding for all of our experience and behavior, but it is an unsteady and subjective one, expanding and contracting like an accordion. Emotions, music, events in our surroundings and shifts in our attention all have the power to speed time up for us or slow it down. When presented with images on a screen, we perceive angry faces as lasting longer than neutral ones, spiders as lasting longer than butterflies, and the color red as lasting longer than blue. The watched pot never boils, and time flies when we’re having fun. Last month in Nature Neuroscience, a trio of researchers at the Weizmann Institute of Science in Israel presented some important new insights into what stretches and compresses our experience of time. They found evidence for a long-suspected connection between time perception and the mechanism that helps us learn through rewards and punishments. They also demonstrated that the perception of time is wedded to our brain’s constantly updated expectations about what will happen next. “Everyone knows the saying that ‘time flies when you’re having fun,’” said Sam Gershman, a cognitive neuroscientist at Harvard University who was not involved in the study. “But the full story might be more nuanced: Time flies when you’re having more fun than you expected.” “Time” doesn’t mean just one thing to the brain. Different brain regions rely on varied neural mechanisms to track its passage, and the mechanisms that govern our experience seem to change from one situation to the next. All Rights Reserved © 2020

Keyword: Attention
Link ID: 27488 - Posted: 09.25.2020

By Bret Stetka With enough training, pigeons can distinguish between the works of Picasso and Monet. Ravens can identify themselves in a mirror. And on a university campus in Japan, crows are known to intentionally leave walnuts in a crosswalk and let passing traffic do their nut cracking. Many bird species are incredibly smart. Yet among intelligent animals, the “bird brain” often doesn’t get much respect. Two papers published today in Science find birds actually have a brain that is much more similar to our complex primate organ than previously thought. For years it was assumed that the avian brain was limited in function because it lacked a neocortex. In mammals, the neocortex is the hulking, evolutionarily modern outer layer of the brain that allows for complex cognition and creativity and that makes up most of what, in vertebrates as a whole, is called the pallium. The new findings show that birds’ do, in fact, have a brain structure that is comparable to the neocortex despite taking a different shape. It turns out that at a cellular level, the brain region is laid out much like the mammal cortex, explaining why many birds exhibit advanced behaviors and abilities that have long befuddled scientists. The new work even suggests that certain birds demonstrate some degree of consciousness. The mammalian cortex is organized into six layers containing vertical columns of neurons that communicate with one another both horizontally and vertically. The avian brain, on the other hand, was thought to be arranged into discrete collections of neurons called nuclei, including a region called the dorsal ventricular ridge, or DVR, and a single nucleus named the wulst. In one of the new papers, senior author Onur Güntürkün, a neuroscientist at Ruhr University Bochum in Germany, and his colleagues analyzed regions of the DVR and wulst involved in sound and vision processing. To do so, they used a technology called three-dimensional polarized light imaging, or 3D-PLI—a light-based microscopy technique that can be employed to visualize nerve fibers in brain samples. The researchers found that in both pigeons and barn owls, these brain regions are constructed much like our neocortex, with both layerlike and columnar organization—and with both horizontal and vertical circuitry. They confirmed the 3D-PLI findings using biocytin tracing, a technique for staining nerve cells. © 2020 Scientific American

Keyword: Evolution; Learning & Memory
Link ID: 27487 - Posted: 09.25.2020