Chapter 17. Learning and Memory

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By Laura Sanders Like all writers, I spend large chunks of my time looking for words. When it comes to the ultracomplicated and mysterious brain, I need words that capture nuance and uncertainties. The right words confront and address hard questions about exactly what new scientific findings mean, and just as importantly, why they matter. The search for the right words is on my mind because of recent research on COVID-19 and the brain. As part of a large brain-scanning study, researchers found that infections of SARS-CoV-2, the virus that causes COVID-19, were linked with less gray matter, tissue that’s packed with the bodies of brain cells. The results, published March 7 in Nature, prompted headlines about COVID-19 causing brain damage and shrinkage. That coverage, in turn, prompted alarmed posts on social media, including mentions of early-onset dementia and brain rotting. As someone who has reported on brain research for more than a decade, I can say those alarming words are not the ones that I would choose here. The study is one of the first to look at structural changes in the brain before and after a SARS-CoV-2 infection. And the study is meticulous. It was done by an expert group of brain imaging researchers who have been doing this sort of research for a very long time. As part of the UK Biobank project, 785 participants underwent two MRI scans. Between those scans, 401 people had COVID-19 and 384 people did not. By comparing the before and after scans, researchers could spot changes in the people who had COVID-19 and compare those changes with people who didn’t get the infection. © Society for Science & the Public 2000–2022.

Keyword: Learning & Memory; Attention
Link ID: 28246 - Posted: 03.19.2022

Jon Hamilton About 1 in 7 people age 60 or older have a brain condition that may be an early sign of Alzheimer's disease. The condition, called mild cognitive impairment, occupies a gray zone between normal aging of the brain and dementia. And most people know almost nothing about it. A national survey found that 82% of Americans are unfamiliar with the condition or know very little about it. More than half thought the symptoms sounded like "normal aging," according to the survey, which was part of a special report released this week by the Alzheimer's Association. "Mild cognitive impairment is often confused with normal aging because it is very subtle," says Maria Carrillo, chief science officer of the Alzheimer's Association. Symptoms include "forgetting people's names, forgetting perhaps that you've said something already, forgetting a story, forgetting words," she says. The condition, which affects about 10 million people in the U.S., is defined as changes in memory and thinking that are noticeable to the affected person and those around them but not serious enough to interfere with the individual's everyday activities. That makes it tricky to diagnose, says Dr. Pierre Tariot, director of the Banner Alzheimer's Institute in Phoenix. So after talking to a patient, Tariot often asks if he can speak with the person's spouse or a close family member. A patient's wife, for example, might notice that her husband is still managing to keep his appointments, Tariot says, but then she adds: "But a year ago, he had it all locked and loaded in his brain. And now, unless he writes it down 12 times and then asks me to double-check, he's not going to get there." © 2022 npr

Keyword: Alzheimers; Learning & Memory
Link ID: 28243 - Posted: 03.19.2022

Yasemin Saplakoglu Imagine that while you are enjoying your morning bowl of Cheerios, a spider drops from the ceiling and plops into the milk. Years later, you still can’t get near a bowl of cereal without feeling overcome with disgust. Researchers have now directly observed what happens inside a brain learning that kind of emotionally charged response. In a new study published in January in the Proceedings of the National Academy of Sciences, a team at the University of Southern California was able to visualize memories forming in the brains of laboratory fish, imaging them under the microscope as they bloomed in beautiful fluorescent greens. From earlier work, they had expected the brain to encode the memory by slightly tweaking its neural architecture. Instead, the researchers were surprised to find a major overhaul in the connections. What they saw reinforces the view that memory is a complex phenomenon involving a hodgepodge of encoding pathways. But it further suggests that the type of memory may be critical to how the brain chooses to encode it — a conclusion that may hint at why some kinds of deeply conditioned traumatic responses are so persistent, and so hard to unlearn. “It may be that what we’re looking at is the equivalent of a solid-state drive” in the brain, said co-author Scott Fraser, a quantitative biologist at USC. While the brain records some types of memories in a volatile, easily erasable form, fear-ridden memories may be stored more robustly, which could help to explain why years later, some people can recall a memory as if reliving it, he said. Memory has frequently been studied in the cortex, which covers the top of the mammalian brain, and in the hippocampus at the base. But it’s been examined less often in deeper structures such as the amygdala, the brain’s fear regulation center. The amygdala is particularly responsible for associative memories, an important class of emotionally charged memories that link disparate things — like that spider in your cereal. While this type of memory is very common, how it forms is not well understood, partly because it occurs in a relatively inaccessible area of the brain. All Rights Reserved © 2022

Keyword: Learning & Memory; Brain imaging
Link ID: 28241 - Posted: 03.16.2022

By Pam Belluck Covid-19 may cause greater loss of gray matter and tissue damage in the brain than naturally occurs in people who have not been infected with the virus, a large new study found. The study, published Monday in the journal Nature, is believed to be the first involving people who underwent brain scans both before they contracted Covid and months after. Neurological experts who were not involved in the research said it was valuable and unique, but they cautioned that the implications of the changes were unclear and did not necessarily suggest that people might have lasting damage or that the changes might profoundly affect thinking, memory or other functions. The study, involving people aged 51 to 81, found shrinkage and tissue damage primarily in brain areas related to sense of smell; some of those areas are also involved in other brain functions, the researchers said. “To me, this is pretty convincing evidence that something changes in brains of this overall group of people with Covid,” said Dr. Serena Spudich, chief of neurological infections and global neurology at the Yale School of Medicine, who was not involved in the study. But, she cautioned: “To make a conclusion that this has some long-term clinical implications for the patients I think is a stretch. We don’t want to scare the public and have them think, ‘Oh, this is proof that everyone’s going to have brain damage and not be able to function.’” The study involved 785 participants in UK Biobank, a repository of medical and other data from about half a million people in Britain. The participants each underwent two brain scans roughly three years apart, plus some basic cognitive testing. In between their two scans, 401 participants tested positive for the coronavirus, all infected between March 2020 and April 2021. The other 384 participants formed a control group because they had not been infected with the coronavirus and had similar characteristics to the infected patients in areas like age, sex, medical history and socioeconomic status. With normal aging, people lose a tiny fraction of gray matter each year. For example, in regions related to memory, the typical annual loss is between 0.2 percent and 0.3 percent, the researchers said. © 2022 The New York Times Company

Keyword: Chemical Senses (Smell & Taste); Learning & Memory
Link ID: 28237 - Posted: 03.11.2022

Dominique Potvin When we attached tiny, backpack-like tracking devices to five Australian magpies for a pilot study, we didn’t expect to discover an entirely new social behaviour rarely seen in birds. Our goal was to learn more about the movement and social dynamics of these highly intelligent birds, and to test these new, durable and reusable devices. Instead, the birds outsmarted us. As our new research paper explains, the magpies began showing evidence of cooperative “rescue” behaviour to help each other remove the tracker. While we’re familiar with magpies being intelligent and social creatures, this was the first instance we knew of that showed this type of seemingly altruistic behaviour: helping another member of the group without getting an immediate, tangible reward. As academic scientists, we’re accustomed to experiments going awry in one way or another. Expired substances, failing equipment, contaminated samples, an unplanned power outage—these can all set back months (or even years) of carefully planned research. For those of us who study animals, and especially behaviour, unpredictability is part of the job description. This is the reason we often require pilot studies. Our pilot study was one of the first of its kind—most trackers are too big to fit on medium to small birds, and those that do tend to have very limited capacity for data storage or battery life. They also tend to be single-use only. A novel aspect of our research was the design of the harness that held the tracker. We devised a method that didn’t require birds to be caught again to download precious data or reuse the small devices. © 1986–2022 The Scientist.

Keyword: Evolution; Learning & Memory
Link ID: 28218 - Posted: 02.26.2022

By Linda Searing Health-care workers and others who are exposed on the job to formaldehyde, even in low amounts, face a 17 percent increased likelihood of developing memory and thinking problems later on, according to research published in the journal Neurology. The finding adds cognitive impairment to already established health risks associated with formaldehyde. As the level of exposure increases, those risks range from eye, nose and throat irritation to skin rashes and breathing problems. At high levels of exposure, the chemical is considered a carcinogen, linked to leukemia and some types of nose and throat cancer. A strong-smelling gas, formaldehyde is used in making building materials and plastics and often as a component of disinfectants and preservatives. Materials containing formaldehyde can release it into the air as a vapor that can be inhaled, which is the main way people are exposed to it. The study, which included data from more than 75,000 people, found that the majority of those exposed were workers in the health-care sector — nurses, caregivers, medical technicians and those working in labs and funeral homes. Other study participants who had been exposed to formaldehyde included workers in textile, chemistry and metal industries; carpenters; and cleaners. At highest risk were those whose work had exposed them to formaldehyde for 22 years or more, giving them a 21 percent higher risk for cognitive problems than those who had not been exposed. Using a battery of standardized tests, the researchers found that formaldehyde exposure created higher risk for every type of cognitive function that was tested, including memory, attention, reasoning, word recall and other thinking skills.

Keyword: Learning & Memory; Neurotoxins
Link ID: 28203 - Posted: 02.16.2022

Jordana Cepelewicz We often think of memory as a rerun of the past — a mental duplication of events and sensations that we’ve experienced. In the brain, that would be akin to the same patterns of neural activity getting expressed again: Remembering a person’s face, for instance, might activate the same neural patterns as the ones for seeing their face. And indeed, in some memory processes, something like this does occur. But in recent years, researchers have repeatedly found subtle yet significant differences between visual and memory representations, with the latter showing up consistently in slightly different locations in the brain. Scientists weren’t sure what to make of this transformation: What function did it serve, and what did it mean for the nature of memory itself? Now, they may have found an answer — in research focused on language rather than memory. A team of neuroscientists created a semantic map of the brain that showed in remarkable detail which areas of the cortex respond to linguistic information about a wide range of concepts, from faces and places to social relationships and weather phenomena. When they compared that map to one they made showing where the brain represents categories of visual information, they observed meaningful differences between the patterns. And those differences looked exactly like the ones reported in the studies on vision and memory. The finding, published last October in Nature Neuroscience, suggests that in many cases, a memory isn’t a facsimile of past perceptions that gets replayed. Instead, it is more like a reconstruction of the original experience, based on its semantic content. All Rights Reserved © 2022

Keyword: Learning & Memory; Language
Link ID: 28202 - Posted: 02.12.2022

By Laura Sanders A tussle with COVID-19 can leave people’s brains fuzzy. SARS-CoV-2, the virus behind COVID-19, doesn’t usually make it into the brain directly. But the immune system’s response to even mild cases can affect the brain, new preliminary studies suggest. These reverberating effects may lead to fatigue, trouble thinking, difficulty remembering and even pain, months after the infection is gone. It’s not a new idea. Immune systems gone awry have been implicated in cognitive problems that come with other viral infections such as HIV and influenza, with disorders such as myalgic encephalomyelitis/chronic fatigue syndrome, or ME/CFS, and even from the damaging effects of chemotherapy. What’s different with COVID-19 is the scope of the problem. Millions of people have been infected, says neurologist Avindra Nath of the National Institutes of Health in Bethesda, Md. “We are now faced with a public health crisis,” he says. Sign up for e-mail updates on the latest coronavirus news and research To figure out ways to treat people for the fuzzy thinking, headaches and fatigue that hang around after a bout with COVID-19, scientists are racing to figure out what’s causing these symptoms (SN: 4/27/21). Cognitive neurologist Joanna Hellmuth at the University of California, San Francisco had a head start. As someone who had studied the effects of HIV on the brain, she quickly noted similarities in the neurological symptoms of HIV and COVID-19. The infections paint “the same exact clinical picture,” she says. HIV-related cognitive symptoms have been linked to immune activation in the body, including the brain. “Maybe the same thing is happening in COVID,” Hellmuth says. © Society for Science & the Public 2000–2022.

Keyword: Neuroimmunology; Learning & Memory
Link ID: 28189 - Posted: 02.05.2022

Anastasia Brodovskaya Jaideep Kapur Epilepsy is a disease marked by recurrent seizures, or sudden periods of abnormal, excessive or synchronous neuronal activity in the brain. One in 26 people in the U.S. will develop epilepsy at some point in their life. While people with mild seizures might experience a brief loss of awareness and muscle twitches, more severe seizures could last for several minutes and lead to injury from falling down and losing control of their limbs. Many people with epilepsy also experience memory problems. Patients often experience retrograde amnesia, where they cannot remember what happened immediately before their seizure. Electroconvulsive therapy, a form of treatment for major depression that intentionally triggers small seizures, can also cause retrograde amnesia. So why do seizures often cause memory loss? We are neurology researchers who study the mechanisms behind how seizures affect the brain. Our brain-mapping study found that seizures affect the same circuits of the brain responsible for memory formation. Understand new developments in science, health and technology, each week One of the earliest descriptions of seizures was written on a Babylonian tablet over 3,000 years ago. Seizures can be caused by a number of factors, ranging from abnormalities in brain structure and genetic mutations to infections and autoimmune conditions. Often, the root cause of a seizure isn’t known. The most common type of epilepsy involves seizures that originate in the brain region located behind the ears, the temporal lobe. Some patients with temporal lobe epilepsy experience retrograde amnesia and are unable to recall events immediately before their seizure. © 2010–2022, The Conversation US, Inc.

Keyword: Epilepsy; Learning & Memory
Link ID: 28187 - Posted: 02.05.2022

ByRodrigo Pérez Ortega A good workout doesn’t just boost your mood—it also boosts the brain’s ability to create new neurons. But exactly how this happens has puzzled researchers for years. “It’s been a bit of a black box,” says Tara Walker, a neuroscientist at the University of Queensland’s Brain Institute. Now, Walker and her colleagues think they have found a key: the chemical element selenium. During exercise, mice produce a protein containing selenium that helps their brains grow new neurons, the team reports today. Scientists may also be able to harness the element to help reverse cognitive decline due to old age and brain injury, the authors say. It’s a “fantastic” study, says Bárbara Cardoso, a nutritional biochemist at Monash University’s Victorian Heart Institute. Her own research has shown selenium—which is found in Brazil nuts, grains, and some legumes—improves verbal fluency and the ability to copy drawings correctly in older adults. “We could start thinking about selenium as a strategy” to treat or prevent cognitive decline in those who cannot exercise or are more vulnerable to selenium deficiency, she says, such as older adults, and stroke and Alzheimer’s disease patients. In 1999, researchers reported that running stimulates the brain to make new neurons in the hippocampus, a region involved in learning and memory. But which molecules were released into the bloodstream to spark this “neurogenesis” remained unclear. So 7 years ago, Walker and her colleagues screened the blood plasma of mice that had exercised on a running wheel in their cages for 4 days, versus mice that had no wheel. The team identified 38 proteins whose levels increased after the workout. © 2022 American Association for the Advancement of Science.

Keyword: Learning & Memory; Obesity
Link ID: 28185 - Posted: 02.05.2022

Dan Robitzski As the coronavirus pandemic continues, scientists are racing to understand the underlying causes and implications of long COVID, the umbrella term for symptoms that persist for at least 12 weeks but often last even longer and affect roughly 30 percent of individuals who contract COVID-19. Evidence for specific risk factors such as diabetes and the presence of autoantibodies is starting to emerge, but throughout the pandemic, one assumption has been that an important indicator of whether a COVID-19 survivor is likely to develop long COVID is the severity of their acute illness. However, a preprint shared online on January 10 suggests that even mild SARS-CoV-2 infections may lead to long-term neurological symptoms associated with long COVID such as cognitive impairment and difficulties with attention and memory, a suite of symptoms often lumped together as “brain fog.” In the study, which has not yet been peer-reviewed, scientists led by Stanford University neurologist Michelle Monje identified a pathway in COVID-19–infected mice and humans that almost perfectly matches the inflammation thought to cause chemotherapy-related cognitive impairment (CRCI), also known as “chemo fog,” following cancer treatments. On top of that, the preprint shows that the neuroinflammation pathway can be triggered even without the coronavirus infecting a single brain cell. As far back as March 2020, Monje feared that cytokine storms caused by the immune response to SARS-CoV-2 would cause the same neuroinflammation and symptoms associated with CRCI, she tells The Scientist. But because her lab doesn’t study viral infections, she had no way to test her hypothesis until other researchers created the appropriate models. In the study, Monje and her colleagues used a mouse model for mild SARS-CoV-2 infections developed at the lab of Yale School of Medicine biologist and study coauthor Akiko Iwasaki as well as brain tissue samples taken from people who had COVID-19 when they died to demonstrate that mild infections can trigger inflammation in the brain. © 1986–2022 The Scientist.

Keyword: Learning & Memory
Link ID: 28182 - Posted: 02.02.2022

By Jason DeParle WASHINGTON — A study that provided poor mothers with cash stipends for the first year of their children’s lives appears to have changed the babies’ brain activity in ways associated with stronger cognitive development, a finding with potential implications for safety net policy. The differences were modest — researchers likened them in statistical magnitude to moving to the 75th position in a line of 100 from the 81st — and it remains to be seen if changes in brain patterns will translate to higher skills, as other research offers reason to expect. Still, evidence that a single year of subsidies could alter something as profound as brain functioning highlights the role that money may play in child development and comes as President Biden is pushing for a much larger program of subsidies for families with children. “This is a big scientific finding,” said Martha J. Farah, a neuroscientist at the University of Pennsylvania, who conducted a review of the study for the Proceedings of the National Academy of Sciences, where it was published on Monday. “It’s proof that just giving the families more money, even a modest amount of more money, leads to better brain development.” Another researcher, Charles A. Nelson III of Harvard, reacted more cautiously, noting the full effect of the payments — $333 a month — would not be clear until the children took cognitive tests. While the brain patterns documented in the study are often associated with higher cognitive skills, he said, that is not always the case. © 2022 The New York Times Company

Keyword: Development of the Brain; Learning & Memory
Link ID: 28172 - Posted: 01.26.2022

Veronique Greenwood In the moment between reading a phone number and punching it into your phone, you may find that the digits have mysteriously gone astray — even if you’ve seared the first ones into your memory, the last ones may still blur unaccountably. Was the 6 before the 8 or after it? Are you sure? Maintaining such scraps of information long enough to act on them draws on an ability called visual working memory. For years, scientists have debated whether working memory has space for only a few items at a time, or if it just has limited room for detail: Perhaps our mind’s capacity is spread across either a few crystal-clear recollections or a multitude of more dubious fragments. The uncertainty in working memory may be linked to a surprising way that the brain monitors and uses ambiguity, according to a recent paper in Neuron from neuroscience researchers at New York University. Using machine learning to analyze brain scans of people engaged in a memory task, they found that signals encoded an estimate of what people thought they saw — and the statistical distribution of the noise in the signals encoded the uncertainty of the memory. The uncertainty of your perceptions may be part of what your brain is representing in its recollections. And this sense of the uncertainties may help the brain make better decisions about how to use its memories. The findings suggests that “the brain is using that noise,” said Clayton Curtis, a professor of psychology and neuroscience at NYU and an author of the new paper. All Rights Reserved © 2022

Keyword: Learning & Memory
Link ID: 28163 - Posted: 01.19.2022

Nicola Davis It’s a cold winter’s day, and I’m standing in a room watching my dog stare fixedly at two flower pots. I’m about to get an answer to a burning question: is my puppy a clever girl? Dogs have been our companions for millennia, domesticated sometime between 15,000 and 30,000 years ago. And the bond endures: according to the latest figures from the Pet Food Manufacturers Association 33% of households in the UK have a dog. But as well as fulfilling roles from Covid detection to lovable family rogue, scientists investigating how dogs think, express themselves and communicate with humans say dogs can also teach us about ourselves. And so I am here at the dog cognition centre at the University of Portsmouth with Calisto, the flat-coated retriever, and a pocket full of frankfurter sausage to find out how. We begin with a task superficially reminiscent of the cup and ballgame favoured by small-time conmen. Amy West, a PhD student at the centre, places two flower pots a few metres in front of Calisto, and appears to pop something under each. However, only one actually contains a tasty morsel. West points at the pot under which the sausage lurks, and I drop Calisto’s lead. The puppy makes a beeline for the correct pot. But according to Dr Juliane Kaminski, reader in comparative psychology at the University of Portsmouth, this was not unexpected. “A chimpanzee is our closest living relative – they ignore gestures like these coming from humans entirely,” she says. “But dogs don’t.” © 2022 Guardian News & Media Limited

Keyword: Learning & Memory; Evolution
Link ID: 28162 - Posted: 01.19.2022

Sophie Fessl Mice raised in an enriched environment are better able to adapt and change than mice raised in standard cages, but why they show this higher brain plasticity has not been known. Now, a study published January 11 in Cell Reports finds that the environment could act indirectly: living in enriched environments changes the animals’ gut microbiota, which appears to modulate plasticity. The study “provides very interesting new insights into possible beneficial effects of environmental enrichment on the brain that might act via the gut,” writes Anthony Hannan, a neuroscientist at the Florey Institute of Neuroscience and Mental Health in Australia who was not involved in the study, in an email to The Scientist. “This new study has implications for how we might understand the beneficial effects of environmental enrichment, and its relevance to cognitive training and physical activity interventions in humans.” In previous studies, mice raised in what scientists call an enriched environment—one in which they have more opportunities to explore, interact with others, and receive sensory stimulation than they would in standard laboratory enclosures—have been better able to modify their neuronal circuits in response to external stimuli than mice raised in smaller, plainer cages. Paola Tognini, a neuroscientist at the University of Pisa and lead author of the new study, writes in an email to The Scientist that she “wondered if endogenous factors (signals coming from inside our body instead of the external world), such as the signals coming from the intestine, could also influence brain plasticity.” © 1986–2022 The Scientist.

Keyword: Learning & Memory; Obesity
Link ID: 28159 - Posted: 01.19.2022

Melinda Wenner Moyer Like many paediatricians, Dani Dumitriu braced herself for the impact of the SARS-CoV-2 coronavirus when it first surged in her wards. She was relieved when most newborn babies at her hospital who had been exposed to COVID-19 seemed to do just fine. Knowledge of the effects of Zika and other viruses that can cause birth defects meant that doctors were looking out for problems. But hints of a more subtle and insidious trend followed close behind. Dumitriu and her team at the NewYork–Presbyterian Morgan Stanley Children’s Hospital in New York City had more than two years of data on infant development — since late 2017, they had been analysing the communication and motor skills of babies up to six months old. Dumitriu thought it would be interesting to compare the results from babies born before and during the pandemic. She asked her colleague Morgan Firestein, a postdoctoral researcher at Columbia University in New York City, to assess whether there were neurodevelopmental differences between the two groups. A few days later, Firestein called Dumitriu in a panic. “She was like, ‘We’re in a crisis, I don’t know what to do, because we not only have an effect of a pandemic, but it’s a significant one,’” Dumitriu recalled. She was up most of that night, poring over the data. The infants born during the pandemic scored lower, on average, on tests of gross motor, fine motor and communication skills compared with those born before it (both groups were assessed by their parents using an established questionnaire)1. It didn’t matter whether their birth parent had been infected with the virus or not; there seemed to be something about the environment of the pandemic itself. Dumitriu was stunned. “We were like, oh, my God,” she recalled. “We’re talking about hundreds of millions of babies.” Although children have generally fared well when infected with SARS-CoV-2, preliminary research suggests that pandemic-related stress during pregnancy could be negatively affecting fetal brain development in some children. Moreover, frazzled parents and carers might be interacting differently or less with their young children in ways that could affect a child’s physical and mental abilities.

Keyword: Development of the Brain; Learning & Memory
Link ID: 28152 - Posted: 01.12.2022

By Lisa Sanders, M.D. The mother stood in the baggage-claim area of the Buffalo Niagara International Airport, waiting for her 37-year-old son, who had just flown in from North Carolina. The carousel was nearly empty by the time she caught sight of him. She was shocked by how sick he looked. His face was pale and thin, his hair and clothes rumpled as if he felt too awful to care. Most surprising of all: He was being rolled toward her in a wheelchair. “I had some trouble with the stairs,” he explained. He thanked the attendant and then struggled to get to his feet. He didn’t make it. Before he got more than a few inches off the seat, his arms and then his legs began to shake and wobble, and he fell heavily back into the chair. His mother collected his bag and pushed him out to where her husband was waiting in the car. On the drive home, the young man struggled to explain what was going on. He had always considered himself to be pretty strong and healthy, but these past few weeks had been rough. It started in his legs. He felt wobbly. When he walked, his hips, legs and especially his feet felt as if they might not be able to hold him up. He saw his physician assistant about it — he worried that it was caused by the cholesterol-lowering medication he had started taking — but the P.A. assured him it wasn’t. He was running a few times a week, but he had to stop because his legs were done well before the run was. And he didn’t feel as sharp as he used to be. His brain seemed foggy and slow. Then this morning he had trouble climbing the stairs to the plane. That was scary. The guy behind him helped by holding up his backpack, but his feet felt like dead weights. He had to use his arms to help get his body up high enough to take each step. Once on the plane, he supported himself on the headrests to get to his assigned seat. They offered the wheelchair when he arrived in Buffalo, and he gratefully accepted. His mother tentatively asked if he thought he should see a doctor. She knew he hated it when she tried to tell him what to do. He had flown up to see a football game with her ex-husband, his father, and a hockey game with his stepbrother. If he didn’t feel any better after that, he conceded, it would be time to see a doctor. © 2022 The New York Times Company

Keyword: Movement Disorders; Drug Abuse
Link ID: 28150 - Posted: 01.12.2022

Don Arnold All memory storage devices, from your brain to the RAM in your computer, store information by changing their physical qualities. Over 130 years ago, pioneering neuroscientist Santiago Ramón y Cajal first suggested that the brain stores information by rearranging the connections, or synapses, between neurons. Since then, neuroscientists have attempted to understand the physical changes associated with memory formation. But visualizing and mapping synapses is challenging to do. For one, synapses are very small and tightly packed together. They’re roughly 10 billion times smaller than the smallest object a standard clinical MRI can visualize. Furthermore, there are approximately 1 billion synapses in the mouse brains researchers often use to study brain function, and they’re all the same opaque to translucent color as the tissue surrounding them. A new imaging technique my colleagues and I developed, however, has allowed us to map synapses during memory formation. We found that the process of forming new memories changes how brain cells are connected to one another. While some areas of the brain create more connections, others lose them. Mapping new memories in fish Previously, researchers focused on recording the electrical signals produced by neurons. While these studies have confirmed that neurons change their response to particular stimuli after a memory is formed, they couldn’t pinpoint what drives those changes. © 2010–2022, The Conversation US, Inc.

Keyword: Learning & Memory
Link ID: 28149 - Posted: 01.12.2022

By Maria Temming It might seem like a fish needs a car like — well, like a fish needs a bicycle. But a new experiment suggests that fish actually make pretty good drivers. In the experiment, several goldfish learned to drive what is essentially the opposite of a submarine — a tank of water on wheels — to destinations in a room. That these fish could maneuver on land suggests that fishes’ understanding of space and navigation is not limited to their natural environment — and perhaps has something in common with landlubber animals’ internal sense of direction, researchers report in the Feb. 15 Behavioural Brain Research. Researchers at Ben-Gurion University of the Negev in Beer-Sheva, Israel taught six goldfish to steer a motorized water tank. The fishmobile was equipped with a camera that continually tracked a fish driver’s position and orientation inside the tank. Whenever the fish swam near one of the tank’s walls, facing outward, the vehicle trundled off in that direction. This goldfish knows how to use its wheels. Successfully navigating in a tank on land suggests that the animals understand space and direction in a way that lets them explore even in unfamiliar habitats. Fish were schooled on how to drive during about a dozen 30-minute sessions. The researchers trained each fish to drive from the center of a small room toward a pink board on one wall by giving the fish a treat whenever it reached the wall. During their first sessions, the fish averaged about 2.5 successful trips to the target. During their final sessions, fish averaged about 17.5 successful trips. By the end of driver’s ed, the animals also took faster, more direct routes to their goal. © Society for Science & the Public 2000–2022.

Keyword: Learning & Memory
Link ID: 28148 - Posted: 01.12.2022

Leonard Mlodinow Charles Darwin created the most successful theory in the history of biology: the theory of evolution. He was also responsible for another grand theory: the theory of emotion, which dominated his field for more than a century. That theory was dead wrong. The most important tenet of his theory was that the mind consists of two competing forces, the rational and the emotional. He believed emotions played a constructive role in the lives of non-human animals, but in humans emotions were a vestige whose usefulness had been largely superseded by the evolution of reason. We now know that, on the contrary, emotions enhance our process of reasoning and aid our decision-making. In fact, we can’t make decisions, or even think, without being influenced by our emotions. Consider a pioneering 2010 study in which researchers analysed the work of 118 professional traders in stocks, bonds and derivatives at four investment banks. Some were highly successful, but many were not. The researchers’ goal was to understand what differentiated the two groups. Their conclusion? They had different attitudes toward the role of emotion in their job. The relatively less successful traders for the most part denied that emotion played a significant role. They tried to suppress their emotions, while at the same time denying that emotions had an effect on their decision-making. The most successful traders, in contrast, had a different attitude. They showed a great willingness to reflect on their emotion-driven behaviour. They recognised that emotion and good decision-making were inextricably linked. Accepting that emotions were necessary for high performance, they “tended to reflect critically about the origin of their intuitions and the role of emotion”. © 2021 Guardian News & Media Limited

Keyword: Emotions; Learning & Memory
Link ID: 28136 - Posted: 01.05.2022