Chapter 17. Learning and Memory

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By Jacob Beck, Sam Clarke Imagine hosting a party. You arrange snacks, curate a playlist and place a variety of beers in the refrigerator. Your first guest shows up, adding a six-pack before taking one bottle for himself. You watch your next guest arrive and contribute a few more beers, minus one for herself. Ready for a drink, you open the fridge and are surprised to find only eight beers remaining. You haven't been consciously counting the beers, but you know there should be more, so you start poking around. Sure enough, in the crisper drawer, behind a rotting head of romaine, are several bottles. How did you know to look for the missing beer? It's not like you were standing guard at the refrigerator, tallying how many bottles went in and out. Rather you were using what cognitive scientists call your number sense, a part of the mind that unconsciously solves simple math problems. While you were immersed in conversation with guests, your number sense was keeping tabs on how many beers were in the fridge. For a long time scientists, mathematicians and philosophers have debated whether this number sense comes preinstalled or is learned over time. Plato was among the first in the Western tradition to propose that humans have innate mathematical abilities. In Plato's dialogue Meno, Socrates coaxes the Pythagorean theorem out of an uneducated boy by asking him a series of simple questions. Socrates's takeaway is that the boy had innate knowledge of the Pythagorean theorem all along; the questioning just helped him express it. In the 17th century John Locke rejected this idea, insisting that the human mind begins as a tabula rasa, or blank slate, with almost all knowledge acquired through experience. This view, known as empiricism, in contrast to Plato's nativism, was later further developed by John Stuart Mill, who argued that we learn two plus three is five by seeing many examples where it holds true: two apples and three apples make five apples, two beers and three beers make five beers, and so on.

Keyword: Development of the Brain; Learning & Memory
Link ID: 28693 - Posted: 03.08.2023

By Stephani Sutherland Tara Ghormley has always been an overachiever. She finished at the top of her class in high school, graduated summa cum laude from college and earned top honors in veterinary school. She went on to complete a rigorous training program and build a successful career as a veterinary internal medicine specialist. But in March 2020 she got infected with the SARS-CoV-2 virus—just the 24th case in the small, coastal central California town she lived in at the time, near the site of an early outbreak in the COVID pandemic. “I could have done without being first at this,” she says. Almost three years after apparently clearing the virus from her body, Ghormley is still suffering. She gets exhausted quickly, her heartbeat suddenly races, and she goes through periods where she can't concentrate or think clearly. Ghormley and her husband, who have relocated to a Los Angeles suburb, once spent their free time visiting their “happiest place on Earth”—Disneyland—but her health prevented that for more than a year. She still spends most of her days off resting in the dark or going to her many doctors' appointments. Her early infection and ongoing symptoms make her one of the first people in the country with “long COVID,” a condition where symptoms persist for at least three months after the infection and can last for years. The syndrome is known by medical professionals as postacute sequelae of COVID-19, or PASC. People with long COVID have symptoms such as pain, extreme fatigue and “brain fog,” or difficulty concentrating or remembering things. As of February 2022, the syndrome was estimated to affect about 16 million adults in the U.S. and had forced between two million and four million Americans out of the workforce, many of whom have yet to return. Long COVID often arises in otherwise healthy young people, and it can follow even a mild initial infection. The risk appears at least slightly higher in people who were hospitalized for COVID and in older adults (who end up in the hospital more often). Women and those at socioeconomic disadvantage also face higher risk, as do people who smoke, are obese, or have any of an array of health conditions, particularly autoimmune disease. Vaccination appears to reduce the danger but does not entirely prevent long COVID.

Keyword: Attention; Learning & Memory
Link ID: 28667 - Posted: 02.15.2023

By Erin Garcia de Jesús Forget screwdrivers or drills. A stick and a straw make for a great cockatoo tool kit. Some Goffin’s cockatoos (Cacatua goffiniana) know whether they need to have more than one tool in claw to topple an out-of-reach cashew, researchers report February 10 in Current Biology. By recognizing that two items are necessary to access the snack, the birds join chimpanzees as the only nonhuman animals known to use tools as a set. The study is a fascinating example of what cockatoos are capable of, says Anne Clark, a behavioral ecologist at Binghamton University in New York, who was not involved in the study. A mental awareness that people often attribute to our close primate relatives can also pop up elsewhere in the animal kingdom. A variety of animals including crows and otters use tools but don’t deploy multiple objects together as a kit (SN: 9/14/16; SN: 3/21/17). Chimpanzees from the Republic of Congo’s Noubalé-Ndoki National Park, on the other hand, recognize the need for both a sharp stick to break into termite mounds and a fishing stick to scoop up an insect feast (SN: 10/19/04). Researchers knew wild cockatoos could use three different sticks to break open fruit in their native range of Indonesia. But it was unclear whether the birds might recognize the sticks as a set or instead as a chain of single tools that became necessary as new problems arose, says evolutionary biologist Antonio Osuna Mascaró of the University of Veterinary Medicine Vienna. © Society for Science & the Public 2000–2023.

Keyword: Learning & Memory; Evolution
Link ID: 28663 - Posted: 02.11.2023

By John M. Beggs Over the last few decades, an idea called the critical brain hypothesis has been helping neuroscientists understand how the human brain operates as an information-processing powerhouse. It posits that the brain is always teetering between two phases, or modes, of activity: a random phase, where it is mostly inactive, and an ordered phase, where it is overactive and on the verge of a seizure. The hypothesis predicts that between these phases, at a sweet spot known as the critical point, the brain has a perfect balance of variety and structure and can produce the most complex and information-rich activity patterns. This state allows the brain to optimize multiple information processing tasks, from carrying out computations to transmitting and storing information, all at the same time. To illustrate how phases of activity in the brain — or, more precisely, activity in a neural network such as the brain — might affect information transmission through it, we can play a simple guessing game. Imagine that we have a network with 10 layers and 40 neurons in each layer. Neurons in the first layer will only activate neurons in the second layer, and those in the second layer will only activate those in the third layer, and so on. Now, I will activate some number of neurons in the first layer, but you will only be able to observe the number of neurons active in the last layer. Let’s see how well you can guess the number of neurons I activated under three different strengths of network connections. First, let’s consider weak connections. In this case, neurons typically activate independently of each other, and the pattern of network activity is random. No matter how many neurons I activate in the first layer, the number of neurons activated in the last layer will tend toward zero because the weak connections dampen the spread of activity. This makes our guessing game incredibly difficult. The amount of information about the first layer that you can learn from the last layer is practically nothing. All Rights Reserved © 2023

Keyword: Attention; Learning & Memory
Link ID: 28652 - Posted: 02.01.2023

By Ellen Barry The effect of social media use on children is a fraught area of research, as parents and policymakers try to ascertain the results of a vast experiment already in full swing. Successive studies have added pieces to the puzzle, fleshing out the implications of a nearly constant stream of virtual interactions beginning in childhood. A new study by neuroscientists at the University of North Carolina tries something new, conducting successive brain scans of middle schoolers between the ages of 12 and 15, a period of especially rapid brain development. The researchers found that children who habitually checked their social media feeds at around age 12 showed a distinct trajectory, with their sensitivity to social rewards from peers heightening over time. Teenagers with less engagement in social media followed the opposite path, with a declining interest in social rewards. The study, published on Tuesday in JAMA Pediatrics, is among the first attempts to capture changes to brain function correlated with social media use over a period of years. The study has important limitations, the authors acknowledge. Because adolescence is a period of expanding social relationships, the brain differences could reflect a natural pivot toward peers, which could be driving more frequent social media use. “We can’t make causal claims that social media is changing the brain,” said Eva H. Telzer, an associate professor of psychology and neuroscience at the University of North Carolina, Chapel Hill, and one of the authors of the study. But, she added, “teens who are habitually checking their social media are showing these pretty dramatic changes in the way their brains are responding, which could potentially have long-term consequences well into adulthood, sort of setting the stage for brain development over time.” © 2023 The New York Times Company

Keyword: Development of the Brain; Stress
Link ID: 28619 - Posted: 01.04.2023

By Shayla Love On Valentine’s Day in 2016, Anne Lantoine received not flowers, but divorce papers. In the months preceding, she had been preparing for her family’s move from France to Canada—or so she thought. She arrived in Quebec early with one of her three children, who was preparing to start college there, while the other two remained in Europe for school. Her husband stayed behind to manage the sale of their house in Marseille. Then the realtors began to complain, through a barrage of calls and emails, to Lantoine. Her husband was not acting like a man who wanted his house sold. He wasn’t answering phone calls and was never available for showings. In January 2016, Lantoine called him after yet another complaint from a realtor. The next morning, he sent her an email with a notice for a court hearing, and she discovered her husband had actually filed for divorce, without telling her, months earlier. That February, she finally got the paperwork, not from her husband, but from her real estate agent. “It was not my last shock,” Lantoine, now 59, recalls. “I also discovered that my husband’s mistress was living in my home.” These revelations were a huge blow practically: It disrupted the immigration paperwork, and Lantoine and her daughter lost their visa applications. But the searing pain was in the betrayal and deceit. “I became very anxious and had constant nightmares,” she says. “I was tired all the time and had panic attacks each time I opened my mail or my emails, or when I had an unidentified phone call.” Though the details of each case vary, romantic betrayal through infidelity, abandonment, or emotional manipulation can upend one’s life in an instant. For Lantoine, her future plans, and the person they were attached to, were suddenly gone, and her functioning along with them. © 2022 NautilusThink Inc, All rights reserved.

Keyword: Stress; Learning & Memory
Link ID: 28612 - Posted: 12.28.2022

By Deborah Blum Back in the year 2000, sitting in his small home office in California’s Mill Valley, surrounded by stacks of spreadsheets, Jay Rosner hit one of those dizzying moments of dismay. An attorney and the executive director of The Princeton Review Foundation, the philanthropic arm of the private test-preparation and tutoring company, The Princeton Review, Rosner was scheduled to give testimony in a highly charged affirmative action lawsuit against the University of Michigan. He knew the case, Grutter v. Bollinger, was eventually headed to the U.S. Supreme Court, but as he reviewed the paperwork, he discovered a daunting gap in his argument.  Rosner had been asked to explore potential racial and cultural biases baked into standardized testing. He believed such biases, which critics had been surfacing for years prior, were real, but in that moment, he felt himself coming up short. “I suddenly realized that I would be deposed on this issue,” he recalled, “and I had no data to support my hypothesis, only deductive reasoning.”   The punch of that realization still resonates. Rosner is the kind of guy who really likes data to stand behind his points, and he recalls an anxiety-infused hunt for some solid facts. Rosner was testifying about an entrance exam for law school, the LSAT, for which he could find no particulars. But he knew that a colleague had data on how students of different racial backgrounds answered specific questions on another powerful standardized test, the SAT, long used to help decide undergraduate admission to colleges — given in New York state. He decided he could use that information to make a case by analogy. The two scholars agreed to crunch some numbers.  Based on past history of test results, he knew that White students would overall have higher scores than Black students. Still, Rosner expected Black students to perform better on some questions. To his shock, he found no trace of such balance. The results were “incredibly uniform,” he said, skewing almost entirely in favor of White students. “Every single question except one in the New York state data on four SATs favored Whites over Blacks,” Rosner recalled.

Keyword: Intelligence; Genes & Behavior
Link ID: 28611 - Posted: 12.24.2022

Jon Hamilton Time is woven into our personal memories. Recall a childhood fall from a bike and the brain replays the entire episode in excruciating detail: the glimpse of wet leaves on the road ahead, the moment of weightless dread, and then the painful impact. This exact sequence has been embedded in the memory, thanks to some special neurons known as time cells. When the brain detects a notable event, time cells begin a highly orchestrated performance, says Marc Howard, who directs the Brain, Behavior, and Cognition program at Boston University. "What we find is that the cells fire in a sequence," he says. "So cell one might fire immediately, but cell two waits a little bit, followed by cell three, cell four, and so on." As each cell fires, it places a sort of time stamp on an unfolding experience. And the same cells fire in the same order when we retrieve a memory of the experience, even something mundane. "If I remember being in my kitchen and making a cup of coffee," Howard says, "the time cells that were active at that moment are re-activated." They recreate the grinder's growl, the scent of Arabica, the curl of steam rising from a fresh mug – and your neurons replay these moments in sequence every time you summon the memory. This system appears to explain how we are able to virtually travel back in time, and play mental movies of our life experiences. There are also hints that time cells play a critical role in imagining future events. Without time cells, our memories would lack order. In an experiment at the University of California, San Diego, scientists gave several groups of people a tour of the campus. The tour included 11 planned events, including finding change in a vending machine and drinking from a water fountain. © 2022 npr

Keyword: Attention; Learning & Memory
Link ID: 28608 - Posted: 12.21.2022

By Anthea Rowan To many, the word “hobby” signifies something lightweight or trivial. Yet taking on a new hobby as one ages might provide an important defense against dementia, some experts say. About 5.8 million adults over 65 in the United States live with Alzheimer’s disease or other dementia disorders, according to the Centers for Disease Control and Prevention. One in 9 Americans over 65 has Alzheimer’s, according to the Alzheimer’s Association. And although the rate of dementia may be falling thanks to lifestyle changes, more of us are living longer, which means the societal burden of dementia is rising. David Merrill, an adult and geriatric psychiatrist and director of the Pacific Brain Health Center in Santa Monica, Calif., suggests we use the word “pursuit” instead of “hobby,” as it elevates the concept of an activity to something demanding, something requiring concentration or collaboration. Something we ought to chase down. Activities that demand focus and industry are the whetstone to keeping cognition sharp, Merrill says. Our brains, he continues, are like any other part of our body. “‘Use it or lose it’ is not just a hypothesis, it’s a basic biologic fact that holds as true for our brains as our muscles or our bones.” While there is as yet no surefire way to prevent dementia or cure it, the Lancet in 2020 identified 12 potentially modifiable risk factors for the condition; they include physiological (blood pressure, diabetes, hearing loss), lifestyle choices (smoking, drinking, physical inactivity), environmental (air pollution) depression, social isolation and a lower level of education. The Alzheimer Society of Canada is also clear about what we can do to help minimize our dementia risk: keep cognitively engaged, learn new things, meet new people, keep a diary, remain curious and engage in conversations.

Keyword: Alzheimers; Learning & Memory
Link ID: 28605 - Posted: 12.21.2022

By Claudia López Lloreda Learning lots of new information as a baby requires a pool of ready-to-go, immature connections between nerve cells to form memories quickly. Called silent synapses, these connections are inactive until summoned to help create memories, and were thought to be present mainly in the developing brain and die off with time. But a new study reveals that there are many silent synapses in the adult mouse brain, researchers report November 30 in Nature. Neuroscientists have long puzzled over how the adult human brain can have stable, long-term memories, while at the same time maintaining a certain flexibility to be able to make new memories, a concept known as plasticity (SN: 7/27/12). These silent synapses may be part of the answer, says Jesper Sjöström, a neuroscientist at McGill University in Montreal who was not involved with the study. “The silent synapses are ready to hook up,” he says, possibly making it easier to store new memories as an adult by using these connections instead of having to override or destabilize mature synapses already connected to memories. “That means that there’s much more room for plasticity in the mature brain than we previously thought.” In a previous study, neuroscientist Mark Harnett of MIT and his colleagues had spotted many long, rod-shaped structures called filopodia in adult mouse brains. That surprised Harnett because these protrusions are mostly found on nerve cells in the developing brain. “Here they were in adult animals, and we could see them crystal clearly,” Harnett says. So he and his team decided to examine the filopodia to see what role they play, and if they were possibly silent synapses. The researchers used a technique to expand the brains of adult mice combined with high-resolution microscopy. Since nerve cell connections and the molecules called receptors that allow for communication between connected cells are so small, these methods revealed synapses that past research missed. © Society for Science & the Public 2000–2022.

Keyword: Learning & Memory
Link ID: 28602 - Posted: 12.17.2022

By Virginia Hughes CRANSTON, R.I. — Audrey Pirri, 16, had been terrified of vomiting since she was a toddler. She worried every time she shared a meal with family or friends, restricting herself to “safe” foods like pretzels and salad that wouldn’t upset her stomach, if she ate at all. She was afraid to ride in the car with her brother, who often got carsick. She fretted for hours about an upcoming visit to a carnival or stadium — anywhere with lots of people and their germs. But on a Tuesday evening in August, in her first intensive session of a treatment called exposure therapy, Audrey was determined to confront one of the most potent triggers of her fear: a set of rainbow polka dot sheets. For eight years she had avoided touching the sheets, ever since the morning when she woke up with a stomach bug and vomited on them. Now, surrounded by her parents, a psychologist and a coach in her pale pink bedroom, she pulled the stiff linens from her dresser, gingerly slid them over the mattress and sat down on top. “You ready to repeat after me?” said Abbe Garcia, the psychologist. “I guess,” Audrey replied softly. “‘I am going to sleep on these sheets tonight,’” Dr. Garcia began. Audrey repeated the phrase. “‘And I might throw up,’” Dr. Garcia said. Audrey paused for several long seconds, her feet twitching and eyes welling with tears, as she imagined herself vomiting. She inhaled deeply and hurried out the words: “And I might throw up.” One in 11 American children has an anxiety disorder, and that figure has been growing steadily for the past two decades. The social isolation, family stress and relentless news of tragedy during the pandemic have only exacerbated the problem. But Audrey is one of the relatively few children to have tried exposure therapy. The decades-old treatment, which is considered a gold-standard approach for tackling anxiety, phobias and obsessive-compulsive disorder, encourages patients to intentionally face the objects or situations that cause them the most distress. A type of cognitive behavioral therapy, exposure often works within months and has minimal side effects. But financial barriers and a lack of providers have kept the treatment out of reach for many. © 2022 The New York Times Company

Keyword: Stress; Learning & Memory
Link ID: 28564 - Posted: 11.23.2022

By Diana Kwon Crows are some of the smartest creatures in the animal kingdom. They are capable of making rule-guided decisions and of creating and using tools. They also appear to show an innate sense of what numbers are. Researchers now report that these clever birds are able to understand recursion—the process of embedding structures in other, similar structures—which was long thought to be a uniquely human ability. Recursion is a key feature of language. It enables us to build elaborate sentences from simple ones. Take the sentence “The mouse the cat chased ran.” Here the clause “the cat chased” is enclosed within the clause “the mouse ran.” For decades, psychologists thought that recursion was a trait of humans alone. Some considered it the key feature that set human language apart from other forms of communication between animals. But questions about that assumption persisted. “There’s always been interest in whether or not nonhuman animals can also grasp recursive sequences,” says Diana Liao, a postdoctoral researcher at the lab of Andreas Nieder, a professor of animal physiology at the University of Tübingen in Germany. In a study of monkeys and human adults and children published in 2020, a group of researchers reported that the ability to produce recursive sequences may not actually be unique to our species after all. Both humans and monkeys were shown a display with two pairs of bracket symbols that appeared in a random order. The subjects were trained to touch them in the order of a “center-embedded” recursive sequence such as { ( ) } or ( { } ). After giving the right answer, humans received verbal feedback, and monkeys were given a small amount of food or juice as a reward. Afterward the researchers presented their subjects with a completely new set of brackets and observed how often they arranged them in a recursive manner. Two of the three monkeys in the experiment generated recursive sequences more often than nonrecursive sequences such as { ( } ), although they needed an additional training session to do so. One of the animals generated recursive sequences in around half of the trials. Three- to four-year-old children, by comparison, formed recursive sequences in approximately 40 percent of the trials. © 2022 Scientific American,

Keyword: Evolution; Learning & Memory
Link ID: 28563 - Posted: 11.23.2022

By Joanna Thompson Two recent papers have shown that during a critical early period of brain development, the gut’s microbiome — the assortment of bacteria that grow within in it — helps to mold a brain system that’s important for social skills later in life. Scientists found this influence in fish, but molecular and neurological evidence plausibly suggests that some form of it could also occur in mammals, including humans. In a paper published in early November in PLOS Biology, researchers found that zebra fish who grew up lacking a gut microbiome were far less social than their peers with colonized colons, and the structure of their brains reflected the difference. In a related article in BMC Genomics in late September, they described molecular characteristics of the neurons affected by the gut bacteria. Equivalents of those neurons appear in rodents, and scientists can now look for them in other species, including humans. In recent decades, scientists have come to understand that the gut and the brain have powerful mutual influences. Certain types of intestinal ulcers, for example, have been linked to worsening symptoms in people with Parkinson’s disease. And clinicians have long known that gastrointestinal disorders are more common in people who also have neurodevelopmental disorders, such as ADHD and autism spectrum disorder. “Not only does the brain have an impact on the gut, but the gut can also profoundly affect the brain,” said Kara Margolis, a pediatric gastroenterologist at New York University’s Langone Health, who was not involved in the new research. How these anatomically separate organs exert their effects, however, is far less clear. Philip Washbourne, a molecular biologist at the University of Oregon and one of the principal co-authors of the new studies, has been studying genes implicated in autism and the development of social behaviors for over two decades. But he and his lab were looking for a new model organism, one that displayed social behavior but was quicker and easier to breed than their go-to, mice. “Can we do this in fish?” he recalls thinking, and then: “Let’s get really quantitative about it and see if we can measure how friendly the fish get.” All Rights Reserved © 2022

Keyword: Sexual Behavior; Obesity
Link ID: 28557 - Posted: 11.16.2022

Emma Marris For the first time, octopuses have been spotted throwing things — at each other1. Octopuses are known for their solitary nature, but in Jervis Bay, Australia, the gloomy octopus (Octopus tetricus) lives at very high densities. A team of cephalopod researchers decided to film the creatures with underwater cameras to see whether — and how — they interact. Once the researchers pulled the cameras out of the water, they sat down to watch more than 20 hours of footage. “I call it octopus TV,” laughs co-author David Scheel, a behavioural ecologist at Alaska Pacific University in Anchorage. One behaviour stood out: instances in which the eight-limbed creatures gathered shells, silt or algae with their arms — and then hurled them away, propelling them with water jetted from their siphon. And although some of the time it seemed that they were just throwing away debris or food leftovers, it did sometimes appear that they were throwing things at each other. The team found clues that the octopuses were deliberately targeting one another. Throws that made contact with another octopus were relatively strong and often occurred when the thrower was displaying a uniform dark or medium body colour. Another clue: sometimes the octopuses on the receiving end ducked. Throws that made octo-contact were also more likely to be accomplished with a specific set of arms, and the projectile was more likely to be silt. “We weren’t able to try and assess what the reasons might be,” Scheel cautions. But throwing, he says, “might help these animals deal with the fact that there are so many octopuses around”. In other words, it is probably social. © 2022 Springer Nature Limited

Keyword: Evolution; Learning & Memory
Link ID: 28549 - Posted: 11.13.2022

Laurel Wamsley Perhaps the real law of the jungle is that it's good to have friends — especially those who know where to find the the free food. Case in point: It turns out chimpanzees and gorillas can be pals, evidently with advantages for all. That finding is from a new paper in the journal iScience that analyzes social interactions between the primate species over two decades at the Nouabalé-Ndoki Park in the Republic of Congo. Over that 20-year period, researchers saw gorillas follow the sound of chimps to a canopy full of ripe figs, and then co-feed at the same tree. They witnessed young individuals of both species playing and wrestling with each other – interactions that can foster their development. And when bands of the two species encountered each other, researchers saw gorillas and chimps scan the others and then approach the ones they knew. They even saw chimpanzees beating their chests – a behavior associated with gorillas. Researchers had theorized that associations between the species could perhaps be to avoid predators such as leopards or snakes. But the apes' behavior didn't show that to be a major factor in their interactions. "Predation is certainly a threat in this region, as we have cases in which chimpanzees have been killed by leopards," Washington University primatologist Crickette Sanz, who led the research, said in a news release. "However, the number of chimpanzees in daily subgroups remains relatively small, and gorillas within groups venture far from the silverback who is thought to be a protector from predation." Instead, better foraging seemed to be a key upside for both species – sometimes eating at the same tree, sometimes dining nearby on different foods. Not every interaction was warm and friendly. "Interspecific aggression was bidirectional and most frequently consisted of threats," the study notes – but it never rose to the level of lethal aggression that has occurred between chimps and gorillas in Gabon. © 2022 npr

Keyword: Evolution; Learning & Memory
Link ID: 28548 - Posted: 11.13.2022

Nicola Davis Science correspondent Playing sounds while you slumber might help to strengthen some memories while weakening others, research suggests, with experts noting the approach might one day help people living with traumatic recollections. Previous work has shown that when a sound is played as a person learns an association between two words, the memory of that word association is boosted if the same sound is played while the individual sleeps. Now researchers have found fresh evidence the approach could also be used to weaken such memories. “We can an actually induce forgetting of specific material whilst people are asleep,” said Dr Aidan Horner, co-author of the study from the University of York. Advertisement Writing in the journal Learning & Memory, Horner and colleagues report how 29 participants were shown pairs of words on a computer screen, one of which was an object word, such as bicycle, while the other was either a place word, such as office, or a person, such as David Beckham. The process was repeated for 60 different object words, and in the course of the process both possible pairings were shown, resulting in 120 associations. As the pairs flashed up, participants heard the object word being spoken out loud. The team tested the participants on a subset of the associations, presenting them with one of the words and asking them to select a paired word from a list of six options. Participants then spent a night in the team’s sleep laboratory. Once they had entered a particular sleep state – as judged by electrodes placed on their heads – they were played audio of 30 of the object words. The team tested participants on the word associations the next day. The results reveal participants’ ability to recall the first word they had learned to pair with an object word was boosted if audio of the latter was played as they slept, compared with if it was not played. However, their ability to recall the second word they learned to associate with the same object decreased relative to the audio-free scenario. © 2022 Guardian News & Media Limited

Keyword: Sleep; Learning & Memory
Link ID: 28516 - Posted: 10.19.2022

Heidi Ledford Hundreds of thousands of human neurons growing in a dish coated with electrodes have been taught to play a version of the classic computer game Pong1. In doing so, the cells join a growing pantheon of Pong players, including pigs taught to manipulate joysticks with their snout2 and monkeys wired to control the game with their minds. (Google’s DeepMind artificial-intelligence (AI) algorithms mastered Pong many years ago3 and have moved on to more-sophisticated computer games such as StarCraft II4.) The gamer cells respond not to visual cues on a screen but to electrical signals from the electrodes in the dish. These electrodes both stimulate the cells and record changes in neuronal activity. Researchers then converted the stimulation signals and the cellular responses into a visual depiction of the game. The results are reported today in Neuron. The work is a proof of principle that neurons in a dish can learn and exhibit basic signs of intelligence, says lead author Brett Kagan, chief scientific officer at Cortical Labs in Melbourne, Australia. “In current textbooks, neurons are thought of predominantly in terms of their implication for human or animal biology,” he says. “They’re not thought about as an information processor, but a neuron is this amazing system that can process information in real time with very low power consumption.” Although the company calls its system DishBrain, the neurons are a far cry from an actual brain, Kagan says, and show no signs of consciousness. The definition of intelligence is also hotly debated; Kagan defines it as the ability to collate information and apply it in an adaptive behaviour in a given environment. Cortical Labs’ work follows on work by neuroengineer Steve Potter, now at the Georgia Institute of Technology in Atlanta, and his colleagues. In 2008, the team reported that neurons cultured from rats can exhibit learning and goal-directed behaviour5,6. Animated gif of 4 different microscopy images of different Dishbrain neural cells with different coloured fluorescent markers. © 2022 Springer Nature Limited

Keyword: Learning & Memory; Intelligence
Link ID: 28511 - Posted: 10.13.2022

By Ed Yong On March 25, 2020, Hannah Davis was texting with two friends when she realized that she couldn’t understand one of their messages. In hindsight, that was the first sign that she had COVID-19. It was also her first experience with the phenomenon known as “brain fog,” and the moment when her old life contracted into her current one. She once worked in artificial intelligence and analyzed complex systems without hesitation, but now “runs into a mental wall” when faced with tasks as simple as filling out forms. Her memory, once vivid, feels frayed and fleeting. Former mundanities—buying food, making meals, cleaning up—can be agonizingly difficult. Her inner world—what she calls “the extras of thinking, like daydreaming, making plans, imagining”—is gone. The fog “is so encompassing,” she told me, “it affects every area of my life.” For more than 900 days, while other long-COVID symptoms have waxed and waned, her brain fog has never really lifted. Of long COVID’s many possible symptoms, brain fog “is by far one of the most disabling and destructive,” Emma Ladds, a primary-care specialist from the University of Oxford, told me. It’s also among the most misunderstood. It wasn’t even included in the list of possible COVID symptoms when the coronavirus pandemic first began. But 20 to 30 percent of patients report brain fog three months after their initial infection, as do 65 to 85 percent of the long-haulers who stay sick for much longer. It can afflict people who were never ill enough to need a ventilator—or any hospital care. And it can affect young people in the prime of their mental lives. Long-haulers with brain fog say that it’s like none of the things that people—including many medical professionals—jeeringly compare it to. It is more profound than the clouded thinking that accompanies hangovers, stress, or fatigue. For Davis, it has been distinct from and worse than her experience with ADHD. It is not psychosomatic, and involves real changes to the structure and chemistry of the brain. It is not a mood disorder: “If anyone is saying that this is due to depression and anxiety, they have no basis for that, and data suggest it might be the other direction,” Joanna Hellmuth, a neurologist at UC San Francisco, told me. (c) 2022 by The Atlantic Monthly Group. All Rights Reserved.

Keyword: Attention; Learning & Memory
Link ID: 28487 - Posted: 09.21.2022

By Erin Garcia de Jesús Human trash can be a cockatoo’s treasure. In Sydney, the birds have learned how to open garbage bins and toss trash around in the streets as they hunt for food scraps. People are now fighting back. Bricks, pool noodles, spikes, shoes and sticks are just some of the tools Sydney residents use to keep sulphur-crested cockatoos (Cacatua galerita) from opening trash bins, researchers report September 12 in Current Biology. The goal is to stop the birds from lifting the lid while the container is upright but still allowing the lid to flop open when a trash bin is tilted to empty its contents. This interspecies battle could be a case of what’s called an innovation arms race, says Barbara Klump, a behavioral ecologist at the Max Planck Institute of Animal Behavior in Radolfzell, Germany. When cockatoos learn how to flip trash can lids, people change their behavior, using things like bricks to weigh down lids, to protect their trash from being flung about (SN Explores: 10/26/21). “That’s usually a low-level protection and then the cockatoos figure out how to defeat that,” Klump says. That’s when people beef up their efforts, and the cycle continues. Researchers are closely watching this escalation to see what the birds — and humans — do next. With the right method, the cockatoos might fly by and keep hunting for a different target. Or they might learn how to get around it. In the study, Klump and colleagues inspected more than 3,000 bins across four Sydney suburbs where cockatoos invade trash to note whether and how people were protecting their garbage. Observations coupled with an online survey showed that people living on the same street are more likely to use similar deterrents, and those efforts escalate over time. © Society for Science & the Public 2000–2022.

Keyword: Learning & Memory; Evolution
Link ID: 28476 - Posted: 09.14.2022

James Brunton Badenoch Monkeypox’s effect on the skin – the disfiguring rashes – and the flu-like symptoms have been well described, but few have investigated the neurological and psychiatric problems the virus might cause. There are historic reports of neurological complications in people infected with the related smallpox virus and in people vaccinated against smallpox, which contains the related vaccinia virus. So my colleagues and I wanted to know whether monkeypox causes similar problems. We looked at all the evidence from before the current monkeypox pandemic of neurological or psychiatric problems in people with a monkeypox infection. The results are published in the journal eClinicalMedicine. A small but noticeable proportion of people (2% to 3%) with monkeypox became very unwell and developed serious neurological problems, including seizure and encephalitis (inflammation of the brain that can cause long-term disability). We also found that confusion occurred in a similar number of people. It’s important to note, though, that these figures are based on a few studies with few participants. Besides the severe and rare brain problems, we found evidence of a broader group of people with monkeypox who had more common neurological symptoms including headache, muscle ache and fatigue. From looking at the studies, it was unclear how severe these symptoms were and how long they lasted. It was also unclear how many people with monkeypox had psychiatric problems - such as anxiety and depression - as few studies looked into it. Of those that did, low mood was frequently reported.. © 2010–2022, The Conversation US, Inc.

Keyword: Epilepsy; Learning & Memory
Link ID: 28475 - Posted: 09.14.2022