Most Recent Links
Follow us on Facebook or subscribe to our mailing list, to receive news updates. Learn more.
By Virginia Morell Leaping over waves or body surfing side by side, dolphins are a fun-loving bunch. But their frolicking—and that of species from hyenas to humans—has long baffled evolutionary biologists. Why expend so much energy on play? A new study offers an intriguing explanation: Juvenile male dolphins use play to acquire the skills required for fathering calves, researchers report today in the Proceedings of the National Academy of Sciences. Most significantly, the scientists found the most playful males go on to have more calves as adults. The study is likely to spur further research into play behavior in additional species, other scientists say. “It’s exciting research, and it solves an evolutionary puzzle,” says Jennifer Smith, a behavioral ecologist at the University of Wisconsin–Eau Claire. “This is the first study to link play behavior in the wild to reproductive success.” Since 1982, scientists have observed some 200 male Indo-Pacific bottlenose dolphins (Tursiops aduncus) in the exceptionally clear waters of Shark Bay in Australia. About 20 years ago, the researchers noticed that young males, 4 to 12 years old, often played together as if they were herding a fertile female, flanking her on either side, while swimming in sync with each other and making popping vocalizations. This kind of “synchronicity is crucial for male reproduction,” says Kathryn Holmes, a behavioral biologist with the Shark Bay Dolphin Research project and lead author of the new study. The young dolphins’ behaviors were strikingly similar to those of the adults. “We wondered if this was ‘play practice’ for the adult behaviors,” Holmes says. So she and her colleagues closely tracked 28 juvenile males for 4 to 5 months over several years, recording their interactions and play behaviors. When socializing, the males “played almost continuously,” Holmes says. “They seemed to never tire of their games.” © 2024 American Association for the Advancement of Science.
Keyword: Sexual Behavior; Evolution
Link ID: 29353 - Posted: 06.11.2024
Elephants call out to each other using individual names that they invent for their fellow pachyderms, according to a new study. While dolphins and parrots have been observed addressing each other by mimicking the sound of others from their species, elephants are the first non-human animals known to use names that do not involve imitation, the researchers suggested. For the new study published on Monday, a team of international researchers used an artificial intelligence algorithm to analyse the calls of two wild herds of African savanna elephants in Kenya. The research “not only shows that elephants use specific vocalisations for each individual, but that they recognise and react to a call addressed to them while ignoring those addressed to others”, the lead study author, Michael Pardo, said. The video player is currently playing an ad. “This indicates that elephants can determine whether a call was intended for them just by hearing the call, even when out of its original context,” the behavioural ecologist at Colorado State University said in a statement. The researchers sifted through elephant “rumbles” recorded at Kenya’s Samburu national reserve and Amboseli national park between 1986 and 2022. Using a machine-learning algorithm, they identified 469 distinct calls, which included 101 elephants issuing a call and 117 receiving one. Elephants make a wide range of sounds, from loud trumpeting to rumbles so low they cannot be heard by the human ear. Names were not always used in the elephant calls. But when names were called out, it was often over a long distance, and when adults were addressing young elephants. Adults were also more likely to use names than calves, suggesting it could take years to learn this particular talent. The most common call was “a harmonically rich, low-frequency sound”, according to the study in the journal Nature Ecology & Evolution. © 2024 Guardian News & Media Limited
Keyword: Animal Communication; Language
Link ID: 29352 - Posted: 06.11.2024
By Janna Levin During traumatic periods and their aftermath, our brains can fall into habitual ways of thinking that may be helpful in the short run but become maladaptive years later. For the brain to readjust to new situations later in life, it needs to be restored to the malleable state it was in when the habits first formed. That is exactly what Gül Dölen, a neuroscientist and psychiatric researcher at the University of California, Berkeley, is working toward in her lab. What is her surprising tool? Psychedelics. JANNA LEVIN: Welcome to “The Joy of Why.” This is Janna Levin. On June 4th, an advisory panel for the Federal Drug Administration recommended against approving the use of the psychedelic drug MDMA as a treatment for post-traumatic stress disorder. Various concerns, some about safety, overshadowed the demonstrable value of the drug in the opinion of the panel. The path to approval for drug therapies is notoriously fraught with profound complexities, a high bar on proof in clinical trials, the medical injunction to “do no harm,” as well as social and political nuances. But, what’s the fundamental neuroscience behind the news story? Why are so many psychiatric researchers enthusiastic about the promise of psychedelics? We happened to take on this subject a few weeks ago with neuroscientist Gül Dölen. Here is that episode. New drug leads can come from practically anywhere. Penicillin’s discovery was spurred from mold spores that accidentally landed in a petri dish. Cancer treatments can be dredged from the bottom of the sea. And synthetic antibodies can now be engineered from scratch. But there’s a class of drugs that mainstream medicine has generally overlooked that could prove life-changing for many people facing addiction, depression, post-traumatic stress — if scientists embrace the potential power of psychedelics. © 2024 the Simons Foundation.
Keyword: Stress; Depression
Link ID: 29351 - Posted: 06.08.2024
By Ellen Barry Post-traumatic stress disorder diagnoses among college students more than doubled between 2017 and 2022, climbing most sharply as the coronavirus pandemic shut down campuses and upended young adults’ lives, according to new research published on Thursday. The prevalence of PTSD rose to 7.5 percent from 3.4 percent during that period, according to the findings. Researchers analyzed responses from more than 390,000 participants in the Healthy Minds Study, an annual web-based survey. “The magnitude of this rise is indeed shocking,” said Yusen Zhai, the paper’s lead author, who heads the community counseling clinic at the University of Alabama at Birmingham. His clinic had seen more young people struggling in the aftermath of traumatic events. So he expected an increase, but not such a large one. Dr. Zhai, an assistant professor in the Department of Human Studies, attributed the rise to “broader societal stressors” on college students, such as campus shootings, social unrest and the sudden loss of loved ones from the coronavirus. PTSD is a mental health disorder characterized by intrusive thoughts, flashbacks and heightened sensitivity to reminders of an event, continuing more than a month after it occurs. It is a relatively common disorder, with an estimated 5 percent of adults in the United States experiencing it in any given year, according to the most recent epidemiological survey conducted by the Department of Health and Human Services. Lifetime prevalence is 8 percent in women and 4 percent in men, the survey found. The new research also found a sharp rise in the prevalence of a similar condition, acute stress disorder, which is diagnosed less than a month after a trauma. Diagnoses rose to 0.7 percent among college students in 2022, up from 0.2 percent five years earlier. Use of mental health care increased nationally during the pandemic, as teletherapy made it far easier to see clinicians. Treatment for anxiety disorders increased most steeply, followed by PTSD, bipolar disorder and depression, according to economists who analyzed more than 1.5 million insurance claims for clinician visits between 2020 and 2022. © 2024 The New York Times Company
Keyword: Stress
Link ID: 29350 - Posted: 06.08.2024
Hannah Devlin Science correspondent A 10-minute brain scan could detect dementia several years before people develop noticeable symptoms, a study suggests. Scientists used a scan of “resting” brain activity to identify whether people would go on to develop dementia, with an estimated 80% accuracy up to nine years before people received a diagnosis. If the findings were confirmed in a larger cohort, the scan could become a routine procedure in memory clinics, scientists said. “We’ve known for a long time that the function of the brain starts to change many years before you get dementia symptoms,” said Prof Charles Marshall, who led the work at Queen Mary University of London. “This could help us to be more precise at identifying those changes using an MRI scan that you could do on any NHS scanner.” The research comes as a new generation of Alzheimer’s drugs are on the horizon. The UK’s Medicines and Healthcare products Regulatory Agency (MHRA) is assessing lecanemab, made by Eisai and Biogen, and donanemab, made by Eli Lilly, and both drugs are widely expected to be licensed this year. “Predicting who is going to get dementia in the future will be vital for developing treatments that can prevent the irreversible loss of brain cells that causes the symptoms of dementia,” Marshall said. The researchers used functional MRI (fMRI) scans from 1,100 UK Biobank volunteers to detect changes in the brain’s “default mode network” (DMN). The scan measures correlations in brain activity between different regions while the volunteer lies still, not doing any particular task. The network, which reflects how effectively different regions are communicating with each other, is known to be particularly vulnerable to Alzheimer’s disease. © 2024 Guardian News & Media Limited
Keyword: Alzheimers; Brain imaging
Link ID: 29349 - Posted: 06.08.2024
By Francine Russo Desperate for sleep, you go to a sleep clinic, where your head is fitted with electrodes to record your brain waves through various sleep stages. In the morning, you report that you barely slept at all. Yet according to the test—polysomnography, the gold standard for sleep measurement—you slept all night. You’re not the classic example of a person with insomnia who waits for sleep to come, maybe checks the clock, paces, reads and waits for morning. What you have has been called subjective insomnia, paradoxical insomnia or sleep misperception. Scientists have doggedly attacked this stubborn puzzle for decades without result—until now. Now they say that you have not been misrepresenting your sleep; they have been mismeasuring it. The most recent studies, using far more enhanced measurement, have found that many people with subjective insomnia show different brain activity from good sleepers—throughout the night. Neuroscientist Aurélie Stephan and colleagues at the Netherlands Institute for Neuroscience (NIN) realized that something unusual was going on after they asked people in their study to put onto their head a net of 256 electrodes rather than the typical six to 20 used in sleep clinics. In one series of experiments, the researchers woke sleepers about 26 times on average during the night. The participants were asked whether they’d been asleep or awake and what they’d been thinking about. The most remarkable finding, Stephan says, is that these people showed pockets of arousal in the form of fast brain waves during rapid eye movement (REM) sleep. REM is the stage in normal sleep when your brain should completely disconnect from the systems that keep you aware and vigilant, Stephan says. © 2024 SCIENTIFIC AMERICAN
Keyword: Sleep
Link ID: 29348 - Posted: 06.08.2024
Ian Sample Science editor Five children who were born deaf now have hearing in both ears after taking part in an “astounding” gene therapy trial that raises hopes for further treatments. The children were unable to hear because of inherited genetic mutations that disrupt the body’s ability to make a protein needed to ensure auditory signals pass seamlessly from the ear to the brain. Doctors at Fudan University in Shanghai treated the children, aged between one and 11, in both ears in the hope they would gain sufficient 3D hearing to take part in conversations and work out which direction sounds were coming from. Within weeks of receiving the therapy, the children had gained hearing, could locate the sources of sounds, and recognised speech in noisy environments. Two of the children were recorded dancing to music, the researchers reported in Nature Medicine. A child facing away from the camera towards a panel of auditory testing equipment with script in the top left corner Dr Zheng-Yi Chen, a scientist at Massachusetts Eye and Ear, a Harvard teaching hospital in Boston that co-led the trial, said the results were “astounding”, adding that researchers continued to see the children’s hearing ability “dramatically progress”. The therapy uses an inactive virus to smuggle working copies of the affected gene, Otof, into the inner ear. Once inside, cells in the ear use the new genetic material as a template to churn out working copies of the crucial protein, otoferlin. Video footage of the patients shows a two-year-old boy responding to his name three weeks after the treatment and dancing to music after 13 weeks, having shown no response to either before receiving the injections. © 2024 Guardian News & Media Limited
Keyword: Hearing; Genes & Behavior
Link ID: 29347 - Posted: 06.06.2024
By Gemma Conroy Researchers have developed biodegradable, wireless sensors that can monitor changes in the brain following a head injury or cancer treatment, without invasive surgery. In rats and pigs, the soft sensors performed just as well as conventional wired sensors for up to a month after being injected under the skull. The gel-based sensors measure key health markers, including temperature, pH and pressure. “It is quite likely this technology will be useful for people in medical settings,” says study co-author Yueying Yang, a biomedical engineer at Huazhong University of Science and Technology (HUST) in Wuhan, China. The findings were published today in Nature1. “It’s a very comprehensive study,” says Christopher Reiche, who develops implantable microdevices at the University of Utah in Salt Lake City. For years, scientists have been developing brain sensors that can be implanted inside the skull. But many of these devices rely on wires to transmit data to clinicians. The wires are difficult to insert and remove, and create openings in the skin for viruses and bacteria to enter the body. Wireless sensors offer a solution to this problem, but are thwarted by their limited communication range and relatively large size. Developing sensors that can access and monitor the brain is “extremely difficult”, says Omid Kavehei, a biomedical engineer who specializes in neurotechnology at the University of Sydney in Australia. To overcome these challenges, Yang and her colleagues created a set of 2-millimetre cube-shaped sensors out of hydrogel, a soft, flexible material that’s often used in tissue regeneration and drug delivery. The gel sensors change shape under different temperatures, pressures and pH conditions, and respond to vibrations caused by variations in blood flow in the brain. When the sensors are implanted under the skull and scanned with an ultrasound probe — a tool that is already used to image the human brain in clinics — these changes are detectable in the form of ultrasonic waves that pass through the skull. The tiny gel-cubes completely dissolve in saline solution after around four months, and begin to break down in the brain after five weeks. © 2024 Springer Nature Limited
Keyword: Brain Injury/Concussion; Brain imaging
Link ID: 29346 - Posted: 06.06.2024
By Betsy Mason To help pay for his undergraduate education, Elias Garcia-Pelegrin had an unusual summer job: cruise ship magician. “I was that guy who comes out at dinnertime and does random magic for you,” he says. But his latest magic gig is even more unusual: performing for Eurasian jays at Cambridge University’s Comparative Cognition Lab. Birds can be harder to fool than tourists. And to do magic for the jays, he had to learn to do sleight-of-hand tricks with a live, wriggling waxworm instead of the customary coin or ball. But performing in an aviary does have at least one advantage over performing on a cruise ship: The birds aren’t expecting to be entertained. “You don’t have to worry about impressing anybody, or tell a joke,” Garcia-Pelegrin says. “So you just do the magic.” In just the last few years, researchers have become interested in what they can learn about animal minds by studying what does and doesn’t fool them. “Magic effects can reveal blind spots in seeing and roadblocks in thinking,” says Nicky Clayton, who heads the Cambridge lab and, with Garcia-Pelegrin and others, cowrote an overview of the science of magic in the Annual Review of Psychology. What we visually perceive about the world is a product of how our brains interpret what our eyes see. Humans and other animals have evolved to handle the immense amount of visual information we’re exposed to by prioritizing some types of information, filtering out things that are usually less relevant and filling in gaps with assumptions. Many magic effects exploit these cognitive shortcuts in humans, and comparing how well these same tricks work on other species may reveal something about how their minds operate. Clayton and her colleagues have used magic tricks with both jays and monkeys to reveal differences in how these animals experience the world. Now they are hoping to expand to more species and inspire other researchers to try magic to explore big questions about complex mental abilities and how they evolved.
Keyword: Attention; Evolution
Link ID: 29345 - Posted: 06.06.2024
By George Musser Had you stumbled into a certain New York University auditorium in March 2023, you might have thought you were at pure neuroscience conference. In fact, it was a workshop on artificial intelligence—but your confusion could have been readily forgiven. Speakers talked about “ablation,” a procedure of creating brain lesions, as commonly done in animal model experiments. They mentioned “probing,” like using electrodes to tap into the brain’s signals. They presented linguistic analyses and cited long-standing debates in psychology over nature versus nurture. Plenty of the hundred or so researchers in attendance probably hadn’t worked with natural brains since dissecting frogs in seventh grade. But their language choices reflected a new milestone for their field: The most advanced AI systems, such as ChatGPT, have come to rival natural brains in size and complexity, and AI researchers are studying them almost as if they were studying a brain in a skull. As part of that, they are drawing on disciplines that traditionally take humans as their sole object of study: psychology, linguistics, philosophy of mind. And in return, their own discoveries have started to carry over to those other fields. These various disciplines now have such closely aligned goals and methods that they could unite into one field, Grace Lindsay, assistant professor of psychology and data science at New York University, argued at the workshop. She proposed calling this merged science “neural systems understanding.” “Honestly, it’s neuroscience that would benefit the most, I think,” Lindsay told her colleagues, noting that neuroscience still lacks a general theory of the brain. “The field that I come from, in my opinion, is not delivering. Neuroscience has been around for over 100 years. I really thought that, when people developed artificial neural systems, they could come to us.” © 2024 Simons Foundation
Keyword: Consciousness; Language
Link ID: 29344 - Posted: 06.06.2024
By Andrew Jacobs An independent advisory panel of the Food and Drug Administration rejected the use of MDMA-assisted therapy for post-traumatic stress disorder on Tuesday, highlighting the unparalleled regulatory challenges of a novel therapy using the drug commonly known as Ecstasy. Before the vote, members of the panel raised concerns about the designs of the two studies submitted by the drug’s sponsor, Lykos Therapeutics. Many questions focused on the fact that study participants were by and large able to correctly guess whether they had been given MDMA, also known by the names of Ecstasy or molly. The panel voted 9-2 on whether the MDMA-assisted therapy was effective, and voted 10-1 on whether the proposed treatment’s benefits outweighed its risks. Other panelists expressed concerns over the drug’s potential cardiovascular effects, and possible bias among the therapists and facilitators who guided the sessions and may have positively influenced patient outcomes. A case of misconduct involving a patient and therapist in the study also weighed on some panelists’ minds. Many of the committee members said they were especially worried about the failure of Lykos to collect detailed data from participants on the potential for abuse of a drug that generates feelings of bliss and well-being. “I absolutely agree that we need new and better treatments for PTSD,” said Paul Holtzheimer, deputy director for research at the National Center for PTSD, a panelist who voted no on the question of whether the benefits of MDMA-therapy outweighed the risks. “However, I also note that premature introduction of a treatment can actually stifle development, stifle implementation and lead to premature adoption of treatments that are either not completely known to be safe, not fully effective or not being used at their optimal efficacy,” he added. © 2024 The New York Times Company
Keyword: Stress; Drug Abuse
Link ID: 29343 - Posted: 06.06.2024
Leyland Cecco in Toronto A leading federal scientist in Canada has alleged he was barred from investigating a mystery brain illness in the province of New Brunswick and said he fears more than 200 people affected by the condition are experiencing unexplained neurological decline. The allegations, made in leaked emails to a colleague seen by the Guardian, have emerged two years after the eastern province closed its investigation into a possible “cluster” of cases. “All I will say is that my scientific opinion is that there is something real going on in [New Brunswick] that absolutely cannot be explained by the bias or personal agenda of an individual neurologist,” wrote Michael Coulthart, a prominent microbiologist. “A few cases might be best explained by the latter, but there are just too many (now over 200).” New Brunswick health officials warned in 2021 that more than 40 residents were suffering from a possible unknown neurological syndrome, with symptoms similar to those of the degenerative brain disorder Creutzfeldt-Jakob disease. Those symptoms were varied and dramatic: some patients started drooling and others felt as though bugs were crawling on their skin. A year later, however, an independent oversight committee created by the province determined that the group of patients had most likely been misdiagnosed and were suffering from known illnesses such as cancer and dementia. The committee and the New Brunswick government also cast doubt on the work of neurologist Alier Marrero, who was initially referred dozens of cases by baffled doctors in the region, and subsequently identified more cases. The doctor has since become a fierce advocate for patients he feels have been neglected by the province. © 2024 Guardian News & Media Limited
Keyword: Alzheimers; Depression
Link ID: 29342 - Posted: 06.04.2024
By Amorina Kingdon Like most humans, I assumed that sound didn’t work well in water. After all, Jacques Cousteau himself called the ocean the “silent world.” I thought, beyond whales, aquatic animals must not use sound much. How wonderfully wrong I was. In water a sound wave travels four and a half times faster, and loses less energy, than in air. It moves farther and faster and carries information better. In the ocean, water exists in layers and swirling masses of slightly different densities, depending on depth, temperature, and saltiness. The physics-astute reader will know that the density of the medium in which sound travels influences its speed. So, as sound waves spread through the sea, their speed changes, causing complex reflection or refraction and bending of the sound waves into “ducts” and “channels.” Under the right circumstances, these ducts and channels can carry sound waves hundreds and even thousands of kilometers. What about other sensory phenomena? Touch and taste work about the same in water as in air. But the chemicals that tend to carry scent move slower in water than in air. And water absorbs light very easily, greatly diminishing visibility. Even away from murky coastal waters, in the clearest seas, light vanishes below several hundred meters and visibility below several dozen. So sound is often the best, if not only, way for ocean and freshwater creatures to signal friends, detect enemies, and monitor the world underwater. And there is much to monitor: Earthquakes, mudslides, and volcanic activity rumble through the oceans, beyond a human’s hearing range. Ice cracks, booms, and scrapes the seafloor. Waves hiss and roar. Raindrops plink. If you listen carefully, you can tell wind speed, rainfall, even drop size, by listening to the ocean as a storm passes. Even snowfall makes a sound. © 2024 NautilusNext Inc.,
Keyword: Animal Communication; Sexual Behavior
Link ID: 29341 - Posted: 06.04.2024
By Andrea Muraski I had a nightmare last night. It began like many of my dreams do – I was on vacation with my extended family. This time, we were in Australia, visiting family friends in a big house. Things took a turn when — in some way that I can’t quite explain — I got mixed up in this Australian family’s jewelry theft and smuggling operation. And I lied about it in front of my relatives, to protect myself and my co-conspirators. Before I woke up, I was terrified I’d be sent to prison. The dream seems bizarre, but when I pick the narrative apart, there are clear connections to my waking life. For instance, I recently listened to a podcast where a pair of fancy hairpins suspiciously go missing during a family gathering. Moreover, I’m moving tomorrow and still have packing to do. When the movers arrive in the morning, if I haven't finished packing, I'll face the consequences of my lack of preparedness – a crime, at least to my subconscious. Dr. Rahul Jandial, neurosurgeon, neuroscientist and author of This is Why You Dream: What Your Sleeping Brain Reveals About Your Waking Life, says the major themes and images of vivid dreams like these are worth paying attention to, and trying to derive meaning from. (For me, I decided that the next time I have to move, I’m taking the day before off!) I spoke with Dr. Jandial about what else we can learn from our dreams, including some of modern science’s most remarkable findings, and theories, about the dreaming brain. 1. Dreams are not random From dream diaries recorded in ancient Egypt and China to reports from anthropologists in the Amazon, to surveys of modern Americans, evidence shows our dreams have a lot in common. For example, being chased and falling are pretty consistent. “Reports of nightmares and erotic dreams are nearly universal,” Jandial says, while people rarely report dreaming about math. Jandial says the lack of math makes sense because the part of your brain primarily responsible for logic — the prefrontal cortex — is typically not involved in dreaming. © 2024 npr
Keyword: Sleep
Link ID: 29340 - Posted: 06.04.2024
By Sumeet Kulkarni As spring turns to summer in the United States, warming conditions have started to summon enormous numbers of red-eyed periodical cicadas out of their holes in the soil across the east of the country. This year sees an exceptionally rare joint emergence of two cicada broods: one that surfaces every 13 years and another with a 17-year cycle. They last emerged together in 1803, when Thomas Jefferson was US president. This year, billions or even trillions of cicadas from these two broods — each including multiple species of the genus Magicicada — are expected to swarm forests, fields and urban neighbourhoods. To answer readers’ cicada questions, Nature sought help from three researchers. Katie Dana is an entomologist affiliated with the Illinois Natural History Survey at the University of Illinois at Urbana-Champaign. John Lill is an insect ecologist at George Washington University in Washington DC. Fatima Husain is a cognitive neuroscientist at the University of Illinois at Urbana-Champaign. Their answers have been edited for length and clarity. Why do periodical cicadas have red eyes? JL: We’re not really sure. We do know that cicadas’ eyes turn red in the winter before the insects come out. The whole coloration pattern in periodical cicadas is very bright: red eyes, black and orange wings. They’re quite different from the annual cicadas, which are green and black, and more camouflaged. It’s a bit of an enigma why the periodical ones are so brightly coloured, given that it just makes them more obvious to predators. There are no associated defences with being brightly coloured — it kind of flies in the face of what we know about bright coloration in a lot of other animals, where usually it’s some kind of signal for toxicity. There also exist mutants with brown, orange, golden or even blue eyes. People hunt for blue-eyed ones; it’s like trying to find a four-leaf clover. © 2024 Springer Nature Limited
Keyword: Animal Communication; Sexual Behavior
Link ID: 29339 - Posted: 06.04.2024
By Rebecca Horne The drawings and photographs of Santiago Ramón y Cajal are familiar to any neuroscientist—and probably anyone even remotely interested in the field. Most people who take a cursory look at his iconic images might assume that he created them using only direct observation. But that’s not the case, according to a paper published in March 2024 by Dawn Hunter, visual artist and associate professor of art at the University of South Carolina, and her colleagues. For instance, the Golgi-stained tissue Ramón y Cajal drew contained neurons that were cut in half—so he painstakingly reconstructed the cells by drawing from elements in multiple slides. And he also fleshed out his illustrations using educated guesses and classical drawing principles, such as contrast and occlusion. In this way, Ramón y Cajal’s art training was essential to his research, Hunter says. She came across Ramón y Cajal’s drawings while creating illustrations for a neuroscience textbook. “The first time I saw his work, out of pure inspiration, I decided to draw it,” she says. “It was in those moments of drawing that I realized his process was more profound and conceptually layered than merely retracing pencil lines with ink. Examining Ramón y Cajal’s work through the act of drawing is a more active experience than viewing his work as a gallery visitor or in a textbook.” In 2015, Hunter installed her drawings and paintings alongside original Ramón y Cajal works in an ongoing exhibition at the U.S. National Institutes of Health (NIH). That effort led to a Fulbright fellowship to Spain in 2017, providing her access to the Legado Cajal archives at the Instituto Cajal National Archives, which contain thousands of Ramón y Cajal artifacts. Hunter spoke to The Transmitter about her research in Spain and her realizations about how Ramón y Cajal worked as an artist and as a scientist. The Transmitter: What do you think your work contributes that is new? Dawn Hunter: It spells out the connection to [Ramón y Cajal’s] art training. There are some things that to me as a painter are obvious to zero in on that nobody’s really talked about. For example, Ramón y Cajal’s copying of the Renaissance painter Rafael’s entire portfolio. That in itself is a profound thing. © 2024 Simons Foundation
Keyword: Brain imaging
Link ID: 29338 - Posted: 06.04.2024
By Emily Underwood You’re driving somewhere, eyes on the road, when you start to feel a tingling sensation in your lower abdomen. That extra-large Coke you drank an hour ago has made its way through your kidneys into your bladder. “Time to pull over,” you think, scanning for an exit ramp. To most people, pulling into a highway rest stop is a profoundly mundane experience. But not to neuroscientist Rita Valentino, who has studied how the brain senses, interprets and acts on the bladder’s signals. She’s fascinated by the brain’s ability to take in sensations from the bladder, combine them with signals from outside of the body, like the sights and sounds of the road, then use that information to act — in this scenario, to find a safe, socially appropriate place to pee. “To me, it’s really an example of one of the beautiful things that the brain does,” she says. Scientists used to think that our bladders were ruled by a relatively straightforward reflex — an “on-off” switch between storing urine and letting it go. “Now we realize it’s much more complex than that,” says Valentino, now director of the division of neuroscience and behavior at the National Institute of Drug Abuse. An intricate network of brain regions that contribute to functions like decision-making, social interactions and awareness of our body’s internal state, also called interoception, participates in making the call. In addition to being mind-bogglingly complex, the system is also delicate. Scientists estimate, for example, that more than 1 in 10 adults have overactive bladder syndrome — a common constellation of symptoms that includes urinary urgency (the sensation of needing to pee even when the bladder isn’t full), nocturia (the need for frequent nightly bathroom visits) and incontinence. Although existing treatments can improve symptoms for some, they don’t work for many people, says Martin Michel, a pharmacologist at Johannes Gutenberg University in Mainz, Germany, who researches therapies for bladder disorders. Developing better drugs has proven so challenging that all major pharmaceutical companies have abandoned the effort, he adds.
Keyword: Miscellaneous
Link ID: 29337 - Posted: 06.02.2024
By Joanne Silberner Think for a minute about the little bumps on your tongue. You probably saw a diagram of those taste bud arrangements once in a biology textbook — sweet sensors at the tip, salty on either side, sour behind them, bitter in the back. But the idea that specific tastes are confined to certain areas of the tongue is a myth that “persists in the collective consciousness despite decades of research debunking it,” according to a review published this month in The New England Journal of Medicine. Also wrong: the notion that taste is limited to the mouth. The old diagram, which has been used in many textbooks over the years, originated in a study published by David Hanig, a German scientist, in 1901. But the scientist was not suggesting that various tastes are segregated on the tongue. He was actually measuring the sensitivity of different areas, said Paul Breslin, a researcher at Monell Chemical Senses Center in Philadelphia. “What he found was that you could detect things at a lower concentration in one part relative to another,” Dr. Breslin said. The tip of the tongue, for example, is dense with sweet sensors but contains the others as well. The map’s mistakes are easy to confirm. If you place a lemon wedge at the tip of your tongue, it will taste sour, and if you put a bit of honey toward the side, it will be sweet. The perception of taste is a remarkably complex process, starting from that first encounter with the tongue. Taste cells have a variety of sensors that signal the brain when they encounter nutrients or toxins. For some tastes, tiny pores in cell membranes let taste chemicals in. Such taste receptors aren’t limited to the tongue; they are also found in the gastrointestinal tract, liver, pancreas, fat cells, brain, muscle cells, thyroid and lungs. We don’t generally think of these organs as tasting anything, but they use the receptors to pick up the presence of various molecules and metabolize them, said Diego Bohórquez, a self-described gut-brain neuroscientist at Duke University. For example, when the gut notices sugar in food, it tells the brain to alert other organs to get ready for digestion. © 2024 The New York Times Company
Keyword: Chemical Senses (Smell & Taste)
Link ID: 29336 - Posted: 06.02.2024
By Elissa Welle The traditional story of Alzheimer’s disease casts two key proteins in starring roles—each with clear stage directions: Plaques of sticky amyloid beta protein accumulate outside neurons as the condition unfolds, and tangles of tau protein gum up the insides of the cells. But it may be time for a rewrite. Amyloid beta, too, coalesces inside neurons and seems to mark them for early death, according to research posted on a preprint server last November. In brain slices from people with Alzheimer’s, but not in those from age-matched controls, cells containing intracellular amyloid beta decreased in number as the disease progressed. At first, the result appeared to be a mistake, says study investigator Alessia Caramello, a postdoctoral researcher in the UK Dementia Research Institute. Intracellular amyloid beta is “nowhere to be found” in most discussions of Alzheimer’s disease, she says. “It’s never mentioned. Never ever.” Instead, the field has long focused on the buildup of amyloid beta outside the cell. But even before those plaques form, there seems to be another pathological event, she says—namely intracellular amyloid—“Why not look at it?” The work from Caramello and her colleagues is not the first to suggest that amyloid beta, or Abeta for short, wreaks havoc inside neurons, not just in the extracellular space between them. This “inside-out” hypothesis, as it has been called, has implications for how scientists understand Alzheimer’s disease. In particular, it could help to account for some big mysteries around the condition—such as why the extent of amyloid beta plaques in the brain doesn’t always correlate with symptoms, why neurons die and why treatments to lessen plaques marginally slow down, but do not halt, the disease. “It just puts a totally different spin on how you need to address this,” says Gunnar Gouras, professor of experimental neurology at Lund University and a proponent of the inside-out hypothesis. “It’s really a cell biological, neurobiological issue that is a bit more complex. And we need to also study this instead of just saying, ‘Abeta is bad; we’ve got to get rid of it.’” © 2024 Simons Foundation
Keyword: Alzheimers
Link ID: 29335 - Posted: 06.02.2024
By Ben Casselman Long before people develop dementia, they often begin falling behind on mortgage payments, credit card bills and other financial obligations, new research shows. A team of economists and medical experts at the Federal Reserve Bank of New York and Georgetown University combined Medicare records with data from Equifax, the credit bureau, to study how people’s borrowing behavior changed in the years before and after a diagnosis of Alzheimer’s or a similar disorder. What they found was striking: Credit scores among people who later develop dementia begin falling sharply long before their disease is formally identified. A year before diagnosis, these people were 17.2 percent more likely to be delinquent on their mortgage payments than before the onset of the disease, and 34.3 percent more likely to be delinquent on their credit card bills. The issues start even earlier: The study finds evidence of people falling behind on their debts five years before diagnosis. “The results are striking in both their clarity and their consistency,” said Carole Roan Gresenz, a Georgetown University economist who was one of the study’s authors. Credit scores and delinquencies, she said, “consistently worsen over time as diagnosis approaches, and so it literally mirrors the changes in cognitive decline that we’re observing.” The research adds to a growing body of work documenting what many Alzheimer’s patients and their families already know: Decision-making, including on financial matters, can begin to deteriorate long before a diagnosis is made or even suspected. People who are starting to experience cognitive decline may miss payments, make impulsive purchases or put money into risky investments they would not have considered before the disease. “There’s not just getting forgetful, but our risk tolerance changes,” said Lauren Hersch Nicholas, a professor at the University of Colorado School of Medicine who has studied dementia’s impact on people’s finances. “It might seem suddenly like a good move to move a diversified financial portfolio into some stock that someone recommended.” © 2024 The New York Times Company
Keyword: Alzheimers
Link ID: 29334 - Posted: 06.02.2024