Chapter 17. Learning and Memory

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By Elizabeth Preston This is Panurgus banksianus, the large shaggy bee. It lives alone, burrowed into sandy grasslands across Europe. It prefers to feed on yellow-flowered members of the aster family. The large shaggy bee also has a very large brain. Just like mammals or birds, insect species of the same size may have different endowments inside their heads. Researchers have discovered some factors linked to brain size in back-boned animals. But in insects, the drivers of brain size have been more of a mystery. In a study published Wednesday in Proceedings of the Royal Society B, scientists scrutinized hundreds of bee brains for patterns. Bees with specialized diets seem to have larger brains, while social behavior appears unrelated to brain size. That means when it comes to insects, the rules that have guided brain evolution in other animals may not apply. “Most bee brains are smaller than a grain of rice,” said Elizabeth Tibbetts, an evolutionary biologist at the University of Michigan who was not involved in the research. But, she said, “Bees manage surprisingly complex behavior with tiny brains,” making the evolution of bee brains an especially interesting subject. Ferran Sayol, an evolutionary biologist at University College London, and his co-authors studied those tiny brains from 395 female bees belonging to 93 species from across the United States, Spain and the Netherlands. Researchers beheaded each insect and used forceps to remove its brain, a curled structure that’s widest in the center. “It reminds me a little bit of a croissant,” Dr. Sayol said. One pattern that emerged was a connection between brain size and how long each bee generation lasted. Bees that only go through one generation each year have larger brains, relative to their body size, than bees with multiple generations a year. © 2020 The New York Times Company

Keyword: Evolution; Learning & Memory
Link ID: 27476 - Posted: 09.16.2020

David Cox Gérard Karsenty was a young scientist trying to make a name for himself in the early 1990s when he first stumbled upon a finding that would go on to transform our understanding of bone, and the role it plays in our body. Karsenty had become interested in osteocalcin, one of the most abundant proteins in bone. He suspected that it played a crucial role in bone remodelling – the process by which our bones continuously remove and create new tissue – which enables us to grow during childhood and adolescence, and also recover from injuries. Intending to study this, he conducted a genetic knockout experiment, removing the gene responsible for osteocalcin from mice. However to his dismay, his mutant mice did not appear to have any obvious bone defects at all. “For him, it was initially a total failure,” says Mathieu Ferron, a former colleague of Karsenty who now heads a research lab studying bone biology at IRCM in Montreal. “In those days it was super-expensive to do modification in the mouse genome.” But then Karsenty noticed something unexpected. While their bones had developed normally, the mice appeared to be both noticeably fat and cognitively impaired. “Mice that don’t have osteocalcin have increased circulating glucose, and they tend to look a bit stupid,” says Ferron. “It may sound silly to say this, but they don’t learn very well, they appear kind of depressed. But it took Karsenty and his team some time to understand how a protein in bone could be affecting these functions. They were initially a bit surprised and terrified as it didn’t really make any sense to them.” © 2020 Read It Later, Inc.

Keyword: Hormones & Behavior; Obesity
Link ID: 27473 - Posted: 09.16.2020

Ian Sample Science editor Brain scans of cosmonauts have revealed the first clear evidence of how the organ adapts to the weird and often sickness-inducing challenge of moving around in space. Analysis of scans taken from 11 cosmonauts, who spent about six months each in orbit, found increases in white and grey matter in three brain regions that are intimately involved in physical movement. The changes reflect the “neuroplasticity” of the brain whereby neural tissue, in this case the cells that govern movement or motor activity, reconfigures itself to cope with the fresh demands of life in orbit. “With the techniques we used, we can clearly see there are microstructural changes in three major areas of the brain that are involved in motor processing,” said Steven Jillings, a neuroscientist at the University of Antwerp in Belgium. Visitors to the International Space Station face a dramatic shock to the system for a whole host of reasons, but one of the most striking is weightlessness. While the space station and its occupants are firmly in the grip of gravity – they are constantly falling around the planet – the body must recalibrate its senses to cope with the extreme environment. Images of the cosmonauts’ brains, taken before and after missions lasting on average 171 days, and again seven months later, confirmed that the cerebrospinal fluid that bathes the brain redistributes itself in orbit, pushing the brain up towards the top of the skull. This also expands fluid-filled cavities called ventricles, which may be linked to a loss of sharpness in the cosmonauts’ vision, a condition called spaceflight-associated neuro-ocular syndrome or Sans. © 2020 Guardian News & Media Limited

Keyword: Learning & Memory
Link ID: 27453 - Posted: 09.05.2020

— Joe Louis Martinez Jr., founder and former director of UTSA’s Neurosciences Institute, passed away on August 29 after a long battle with liver cancer. He was 76. Martinez was born in Albuquerque, New Mexico, on August 1, 1944. He received his B.A. from the University of California, San Diego; graduated with his M.S. in experimental psychology from New Mexico Highlands University in 1968; and earned his Ph.D. in physiological psychology in 1971 from the University of Delaware. He completed his postdoctoral training at the University of California, Irvine, and the Salk Institute in San Diego. Martinez served as a professor in the Department of Psychology at the University of California, Berkeley, from 1982 to 1995. During this time he led an internationally recognized research laboratory and departed as professor emeritus. In 1995 he joined UTSA as the Ewing Halsell Distinguished Chair in psychology. From 1995 to 2012 he was a beloved professor who founded and directed the Cajal Neuroscience Research Center, now known as the UTSA Neurosciences Institute. He oversaw the design and construction of the Biosciences Building, UTSA’s first research building. Each floor in the BSB contains tiles representing the neuroanatomical drawings of Santiago Ramon y Cajal. During his tenure at UTSA, Martinez brought over $15 million in grant funding to the university. In 2013 he moved to the University of Illinois at Chicago to become the chair of the department of psychology. He retired in 2016. © 2020 The University of Texas at San Antonio

Keyword: Learning & Memory
Link ID: 27450 - Posted: 09.05.2020

Alison Abbott Two years ago, Jennifer Li and Drew Robson were trawling through terabytes of data from a zebrafish-brain experiment when they came across a handful of cells that seemed to be psychic. The two neuroscientists had planned to map brain activity while zebrafish larvae were hunting for food, and to see how the neural chatter changed. It was their first major test of a technological platform they had built at Harvard University in Cambridge, Massachusetts. The platform allowed them to view every cell in the larvae’s brains while the creatures — barely the size of an eyelash — swam freely in a 35-millimetre-diameter dish of water, snacking on their microscopic prey. Out of the scientists’ mountain of data emerged a handful of neurons that predicted when a larva was next going to catch and swallow a morsel. Some of these neurons even became activated many seconds before the larva fixed its eyes on the prey1. Something else was strange. Looking in more detail at the data, the researchers realized that the ‘psychic’ cells were active for an unusually long time — not seconds, as is typical for most neurons, but many minutes. In fact, more or less the duration of the larvae’s hunting bouts. “It was spooky,” says Li. “None of it made sense.” Li and Robson turned to the literature and slowly realized that the cells must be setting an overall ‘brain state’ — a pattern of prolonged brain activity that primed the larvae to engage with the food in front of them. The pair learnt that, in the past few years, other scientists using various approaches and different species had also found internal brain states that alter how an animal behaves, even when nothing has changed in its external environment. © 2020 Springer Nature Limited

Keyword: Attention; Learning & Memory
Link ID: 27417 - Posted: 08.12.2020

By Chimamanda Ngozi Adichie My daughter and I were playing tag, or a kind of tag. Before that, we traced the letter P and we danced to James Brown’s “I feel good,” a song she selected from the iPod. We laughed as we danced, she with a natural rhythm striking for a 4-year-old, and I with my irretrievable gracelessness. Next on our plan was “Sesame Street.” It was about 2 p.m. on May 28. A day complacent with the promise of no surprises, like all the other days of the lockdown, shrunken days with shriveled routines. “When coronavirus is over,” my daughter often said, words filled with yearning for her preschool, her friends, her swimming lessons. And I, amid snatches of joy and discovery, often felt bored, and then guilty for feeling boredom, in this expanded boundless role of parent-playmate. My daughter picked up a green balloon pump, squirted the air at me, and ran off, around the kitchen counter. When I caught her, squealing, it was her turn to chase me. I was wearing white slippers, from some hotel somewhere, back when international travel was normal. They felt soft and thin-soled. I recall all these clearly, because of all the things I will be unable to recall later. I turned away from the kitchen to make the chase longer and something happened. I slipped or I tripped or my destiny thinned and I fell and hit my head on the hardwood floor. At the beginning of the stay-at-home order, plagued by amorphous anxieties, I taught my daughter how to call my doctor husband at work. Just in case. My daughter says that after I fell I told her, “Call Papa.” My husband says I spoke coherently. I told him that I fell and that the pain in my head was “excruciating,” and when I said “excruciating,” I seemed to wince. He says he asked my daughter to get me the ice pack in the freezer and that I said, “Thank you, baby,” when she gave it to me. I do not remember any of this.

Keyword: Learning & Memory; Brain Injury/Concussion
Link ID: 27412 - Posted: 08.11.2020

By Laura Sanders Exercise’s power to boost the brain might require a little help from the liver. A chemical signal from the liver, triggered by exercise, helps elderly mice keep their brains sharp, suggests a study published in the July 10 Science. Understanding this liver-to-brain signal may help scientists develop a drug that benefits the brain the way exercise does. Lots of studies have shown that exercise helps the brain, buffering the memory declines that come with old age, for instance. Scientists have long sought an “exercise pill” that could be useful for elderly people too frail to work out or for whom exercise is otherwise risky. “Can we somehow get people who can’t exercise to have the same benefits?” asks Saul Villeda, a neuroscientist at the University of California, San Francisco. Villeda and colleagues took an approach similar to experiments that revealed the rejuvenating effects of blood from young mice (SN: 5/5/14). But instead of youthfulness, the researchers focused on fitness. The researchers injected sedentary elderly mice with plasma from elderly mice that had voluntarily run on wheels over the course of six weeks. After eight injections over 24 days, the sedentary elderly mice performed better on memory tasks, such as remembering where a hidden platform was in a pool of water, than elderly mice that received injections from sedentary mice. Comparing the plasma of exercised mice with that of sedentary mice showed an abundance of proteins produced by the liver in mice that ran on wheels. The researchers closely studied one of these liver proteins produced in response to exercise, called GPLD1. GPLD1 is an enzyme, a type of molecular scissors. It snips other proteins off the outsides of cells, releasing those proteins to go do other jobs. Targeting these biological jobs with a molecule that behaves like GPLD1 might be a way to mimic the brain benefits of exercise, the researchers suspect. © Society for Science & the Public 2000–2020.

Keyword: Learning & Memory; Development of the Brain
Link ID: 27358 - Posted: 07.11.2020

By Gretchen Reynolds When we start to lift weights, our muscles do not strengthen and change at first, but our nervous systems do, according to a fascinating new study in animals of the cellular effects of resistance training. The study, which involved monkeys performing the equivalent of multiple one-armed pull-ups, suggests that strength training is more physiologically intricate than most of us might have imagined and that our conception of what constitutes strength might be too narrow. Those of us who join a gym — or, because of the current pandemic restrictions and concerns, take up body-weight training at home — may feel some initial disappointment when our muscles do not rapidly bulge with added bulk. In fact, certain people, including some women and most preadolescent children, add little obvious muscle mass, no matter how long they lift. But almost everyone who starts weight training soon becomes able to generate more muscular force, meaning they can push, pull and raise more weight than before, even though their muscles may not look any larger and stronger. Scientists have known for some time that these early increases in strength must involve changes in the connections between the brain and muscles. The process appears to involve particular bundles of neurons and nerve fibers that carry commands from the brain’s motor cortex, which controls muscular contractions, to the spinal cord and, from there, to the muscles. If those commands become swifter and more forceful, the muscles on the receiving end should respond with mightier contractions. Functionally, they would be stronger. © 2020 The New York Times Company

Keyword: Movement Disorders; Learning & Memory
Link ID: 27343 - Posted: 07.02.2020

Jason Bruck Human actions have taken a steep toll on whales and dolphins. Some studies estimate that small whale abundance, which includes dolphins, has fallen 87% since 1980 and thousands of whales die from rope entanglement annually. But humans also cause less obvious harm. Researchers have found changes in the stress levels, reproductive health and respiratory health of these animals, but this valuable data is extremely hard to collect. To better understand how people influence the overall health of dolphins, my colleagues and I at Oklahoma State University’s Unmanned Systems Research Institute are developing a drone to collect samples from the spray that comes from their blowholes. Using these samples, we will learn more about these animals’ health, which can aid in their conservation. Today, researchers wanting to measure wild dolphins’ health primarily use remote biopsy darting – where researchers use a small dart to collect a sample of tissue – or handle the animals in order to collect samples. These methods don’t physically harm the animals, but despite precautions, they can be disruptive and stressful for dolphins. Additionally, this process is challenging, time-consuming and expensive. My current research focus is on dolphin perception – how they see, hear and sense the world. Using my experience, I am part of a team building a drone specifically designed to be an improvement over current sampling methods, both for dolphins and the researchers. Our goal is to develop a quiet drone that can fly into a dolphin’s blind spot and collect samples from the mucus that is mixed with water and air sprayed out of a dolphin’s blowhole when they exhale a breath. This is called the blow. Dolphins would experience less stress and teams could collect more samples at less expense. © 2010–2020, The Conversation US, Inc.

Keyword: Learning & Memory; Evolution
Link ID: 27342 - Posted: 07.02.2020

By Melinda Wenner Moyer For three months, Chelsea Alionar has struggled with fevers, headaches, dizziness and a brain fog so intense it feels like early dementia. She came down with the worst headache of her life on March 9, then lost her sense of taste and smell. She eventually tested positive for the coronavirus. But her symptoms have been stranger, and lasted longer, than most. “I tell the same stories repeatedly; I forget words I know,” she told me. Her fingers and toes have been numb, her vision blurry and her fatigue severe. The 37-year-old is a one of the more than 4,000 members of a Facebook support group for Covid survivors who have been ill for more than 80 days. The more we learn about the coronavirus, the more we realize it’s not just a respiratory infection. The virus can ravage many of the body’s major organ systems, including the brain and central nervous system. Among patients hospitalized for Covid-19 in Wuhan, China, more than a third experienced nervous system symptoms, including seizures and impaired consciousness. Earlier this month, French researchers reported that 84 percent of Covid patients who had been admitted to the I.C.U. experienced neurological problems, and that 33 percent continued to act confused and disoriented when they were discharged. According to Dr. Mady Hornig, a psychiatrist and epidemiologist at the Columbia University Mailman School of Public Health, the possibility that neurological issues “will persist and create disability, or difficulties, for individuals downstream is really looking more and more likely.” Infections have long been implicated in neurological diseases. Syphilis and H.I.V. can induce dementia. Zika is known to invade developing brains and limit their growth, while untreated Lyme disease can cause nerve pain, facial palsy and spinal cord inflammation. One man with SARS developed delirium that progressed into coma, and was found to have the virus in his brain tissue after his death. © 2020 The New York Times Company

Keyword: Alzheimers; Learning & Memory
Link ID: 27335 - Posted: 06.29.2020

By Jack J. Lee For some bottlenose dolphins, finding a meal may be about who you know. Dolphins often learn how to hunt from their mothers. But when it comes to at least one foraging trick, Indo-Pacific bottlenose dolphins in Western Australia’s Shark Bay pick up the behavior from their peers, researchers argue in a report published online June 25 in Current Biology. While previous studies have suggested that dolphins learn from peers, this study is the first to quantify the importance of social networks over other factors, says Sonja Wild, a behavioral ecologist at the University of Konstanz in Germany. Cetaceans — dolphins, whales and porpoises — are known for using clever strategies to round up meals. Humpback whales (Megaptera novaeangliae) off Alaska sometimes use their fins and circular bubble nets to catch fish (SN: 10/15/19). At Shark Bay, Indo-Pacific bottlenose dolphins (Tursiops aduncus) use sea sponges to protect their beaks while rooting for food on the seafloor, a strategy the animals learn from their mothers (SN: 6/8/05). These Shark Bay dolphins also use a more unusual tool-based foraging method called shelling. A dolphin will trap underwater prey in a large sea snail shell, poke its beak into the shell’s opening, lift the shell above the water’s surface and shake the contents into its mouth. © Society for Science & the Public 2000–2020.

Keyword: Learning & Memory; Evolution
Link ID: 27328 - Posted: 06.26.2020

Tracking the brain’s reaction to virtual-reality-simulated threats such as falling rocks and an under-researched fear reduction strategy may provide better ways of treating anxiety disorders and preventing relapses. Hippocrates described them as ‘masses of terrors,’ while French physicians in the 18th century labelled them as ‘vapours’ and ‘melancholia.’ Nowadays we know that panic attacks, a common symptom of anxiety, can be linked to intense phobias or even a general anxiety disorder with no specific source. ‘But if you’re not sure what a panic attack is, it’s very frightening,’ said Dr Iris Lange, a psychologist based at KU Leuven, in Belgium. ‘You probably think you will get a heart attack. We see a lot of people having to go to the medical emergency services.’ According to an EU and OECD report from 2018, anxiety disorders are the most common mental disorder across European Union countries and affect an estimated 25 million people. Decades of research have shown how anxiety amplifies sensitivity to threats. People with high anxiety will perceive even non-harmful things, such as insects, as potential threats. However, researchers have until recently used mice and rat experiments to understand the neuroscientific concepts of how anxiety patients behave when defending themselves from such perceived threats. ‘We are translating concepts that are probably not translatable (to humans), or we're just translating very core concepts,’ said Professor Dominik R Bach, a neuroscientist at University College London, in the UK.

Keyword: Stress; Learning & Memory
Link ID: 27305 - Posted: 06.17.2020

Natalie Dombois for Quanta Magazine It’s not surprising that the fruit fly larva in the laboratory of Jimena Berni crawls across its large plate of agar in search of food. “A Drosophila larva is either eating or not eating, and if it’s not eating, it wants to eat,” she said. The surprise is that this larva can search for food at all. Owing to a suite of genetic tricks performed by Berni, it has no functional brain. In fact, the systems that normally relay sensations of touch and feedback from its muscles have also been shut down. Berni, an Argentinian neuroscientist whose investigations of fruit fly nervous systems recently earned her a group leader position at the University of Sussex, is learning what the tiny cluster of neurons that directly controls the larva’s muscles does when it’s allowed to run free, entirely without input from the brain or senses. How does the animal forage when it’s cut off from information about the outside world? The answer is that it moves according to a very particular pattern of random movements, a finding that thrilled Berni and her collaborator David Sims, a professor of marine ecology at the Marine Biological Association in Plymouth, U.K. For in its prowl for food, this insensate maggot behaves exactly like an animal Sims has studied for more than 25 years — a shark. In neuroscience, the usual schema for considering behavior has it that the brain receives inputs, combines them with stored information, then decides what to do next. This corresponds to our own intuitions and experiences, because we humans are almost always responding to what we sense and remember. But for many creatures, useful information isn’t always available, and for them something else may also be going on. When searching their environment, sharks and a diverse array of other species, now including fruit fly larvae, sometimes default to the same pattern of movement, a specific type of random motion called a Lévy walk. All Rights Reserved © 2020

Keyword: Learning & Memory; Aggression
Link ID: 27301 - Posted: 06.13.2020

Ruth Williams In the hippocampus of the adult mouse brain, newly formed cells that become activated by a learning experience are later reactivated in the REM phase of sleep, according to a study in Neuron today (June 4). The authors show this reactivation is necessary for fortifying the encoding of the memory. “It is a very cool paper,” writes neuroscientist Sheena Josselyn of the University of Toronto in an email to The Scientist. “This is the first study to causally link new neurons to sleep-dependent memory consolidation. I am sure it will have a broad impact on scientists studying memory, sleep as well as those interested in adult neurogenesis,” she says. Josselyn was not involved in the study. In the adult mammalian brain, most cells do not replicate. But, deep in the center of the organ, in a particular region of the hippocampus called the dentate gyrus, new neurons continue to be born at a slow rate throughout the lifetime of the animal. This neurogenesis is thought to be important for memory formation among other cognitive tasks. Indeed, if the activities of mouse adult-born neurons (ABNs) are perturbed during a learning experience, the animal will not memorize the event as effectively as it does when these cells are left alone. Learning is just one part of forming a memory, however. For memories to last, sleep, and in particular REM sleep, is essential. “Sleep deprivation generally decreases neurogenesis,” writes neuroscientist Masanori Sakaguchi of the International Institute for Integrative Sleep Medicine at the University of Tsukuba in an email to The Scientist. The question was, says Sakaguchi, “is there any function of adult-born neurons during sleep?” To find out, Sakaguchi’s team first examined the activity of mouse ABNs after a learning experience—a contextual fear conditioning in which the animals’ feet were shocked as they explored a particular cage—and during subsequent sleep. Using miniaturized microscopes attached to the skulls of freely moving mice and fluorescent markers to track ABN activities, the team showed that the ABNs that had been activated after the context-shock learning event were more likely to then be reactivated during the animals’ next REM phases of sleep. © 1986–2020 The Scientist

Keyword: Neurogenesis; Sleep
Link ID: 27298 - Posted: 06.10.2020

By Amanda Heidt Human beings typically don’t leave the nest until well into our teenage years—a relatively rare strategy among animals. But corvids—a group of birds that includes jays, ravens, and crows—also spend a lot of time under their parents’ wings. Now, in a parallel to humans, researchers have found that ongoing tutelage by patient parents may explain how corvids have managed to achieve their smarts. Corvids are large, big-brained birds that often live in intimate social groups of related and unrelated individuals. They are known to be intelligent—capable of using tools, recognizing human faces, and even understanding physics—and some researchers believe crows may rival apes for smarts. Meanwhile, humans continue to grow their big brains and build up their cognitive abilities during childhood, as their parents feed and protect them. “Humans are characterized by this extended childhood that affects our intelligence, but we can’t be the only ones,” says Natalie Uomini, a cognitive scientist at the Max Planck Institute for the Science of Human History. But few researchers have studied the impact of parenting throughout the juvenile years on intelligence in nonhumans. To study the link between parental care and intelligence in birds, Uomini and her team created a database detailing the life history of thousands of species, including more than 120 corvids. Compared with other birds, they found corvids spend more time in the nest before fledging, more days feeding their offspring as adults, and more of their life living among family. The results, reported last week in the Philosophical Transactions of the Royal Society B, also confirm corvids have unusually large brains compared with many other birds. Birds need to be light for flight, but a raven’s brain accounts for almost 2% of its body mass, a value similar to humans. © 2020 American Association for the Advancement of Science.

Keyword: Evolution; Intelligence
Link ID: 27295 - Posted: 06.09.2020

Ruth Williams With their tiny brains and renowned ability to memorize nectar locations, honeybees are a favorite model organism for studying learning and memory. Such research has indicated that to form long-term memories—ones that last a day or more—the insects need to repeat a training experience at least three times. By contrast, short- and mid-term memories that last seconds to minutes and minutes to hours, respectively, need only a single learning experience. Exceptions to this rule have been observed, however. For example, in some studies, bees formed long-lasting memories after a single learning event. Such results are often regarded as circumstantial anomalies, and the memories formed are not thought to require protein synthesis, a molecular feature of long-term memories encoded by repeated training, says Martin Giurfa of the University of Toulouse. But the anomalous findings, together with research showing that fruit flies and ants can form long-term memories after single experiences, piqued Giurfa’s curiosity. Was it possible that honeybees could reliably do the same, and if so, what molecular mechanisms were required? Giurfa reasoned that the ability to form robust memories might depend on the particular type of bee and the experience. Within a honeybee colony, there are nurses, who clean the hive and feed the young; guards, who patrol and protect the hive; and foragers, who search for nectar. Whereas previous studies have tested bees en masse, Giurfa and his colleagues focused on foragers, tasking them with remembering an experience relevant to their role: an odor associated with a sugary reward. © 1986–2020 The Scientist.

Keyword: Learning & Memory; Evolution
Link ID: 27272 - Posted: 06.01.2020

Diana Kwon What if you could boost your brain’s processing capabilities simply by sticking electrodes onto your head and flipping a switch? Berkeley, California–based neurotechnology company Humm has developed a device that it claims serves that purpose. Their “bioelectric memory patch” is designed to enhance working memory—the type of short-term memory required to temporarily hold and process information—by noninvasively stimulating the brain. In recent years, neurotechnology companies have unveiled direct-to-consumer (DTC) brain stimulation devices that promise a range of benefits, including enhancing athletic performance, increasing concentration, and reducing depression. Humm’s memory patch, which resembles a large, rectangular Band-Aid, is one such product. Users can stick the device to their forehead and toggle a switch to activate it. Electrodes within the patch generate transcranial alternating current stimulation (tACS), a method of noninvasively zapping the brain with oscillating waves of electricity. The company recommends 15 minutes of stimulation to give users up to “90 minutes of boosted learning” immediately after using the device. The product is set for public release in 2021. Over the last year or so, Humm has generated much excitement among investors, consumers, and some members of the scientific community. In addition to raising several million dollars in venture capital funding, the company has drawn interest both from academic research labs and from the United States military. According to Humm cofounder and CEO Iain McIntyre, the US Air Force has ordered approximately 1,000 patches to use in a study at their training academy that is set to start later this year. © 1986–2020 The Scientist

Keyword: Learning & Memory
Link ID: 27269 - Posted: 05.29.2020

Alejandra Manjarrez The brain is a master of forming patterns, even when it involves events occurring at different times. Take the phenomenon of trace fear conditioning—scientists can get an animal to notice the relationship between a neutral stimulus and an aversive stimulus separated by a temporal chasm (the trace) of a few or even tens of seconds. While it’s a well-established protocol in neuroscience and psychology labs, the mechanism for how the brain bridges the time gap between two related stimuli in order to associate them is “one of the most enigmatic and highly investigated” questions, says Columbia University neuroscientist Attila Losonczy. If the first stimulus is finished, the information about its presence and identity “should be somehow maintained through some neuronal mechanism,” he explains, so it can be associated with the second stimulus coming later. Losonczy and his colleagues have recently investigated how this might occur in a study published May 8 in Neuron. They measured the neural activity in the hippocampal CA1 region of the brain—known to be crucial for the formation of memories—of mice exposed to trace fear conditioning. The team found that associating the two events separated by time involved the activation of a subset of neurons that fired sparsely every time mice received the first stimulus and during the time gap that followed. The pattern emerged only after mice had learned to associate both stimuli. The study highlights “the important question of how we link memories across time,” says Denise Cai, a neuroscientist at the Icahn School of Medicine at Mount Sinai who was not involved in the work. Studying the basic mechanisms of temporal association is critical for understanding how it goes wrong in disorders such as post-traumatic stress disorder (PTSD) or Alzheimer’s disease, she says. © 1986–2020 The Scientist

Keyword: Learning & Memory; Stress
Link ID: 27254 - Posted: 05.18.2020

Sukanya Charuchandra Even for Darold Treffert, an expert in the study of savants who has met around 300 people with conditions such as autism who possess extraordinary mental abilities, Kim Peek stood out from the pack. Treffert first spoke with Peek on the phone in the 1980s. Peek asked Treffert for his date of birth and then proceeded to recount historical events that had taken place on that day and during that week, Treffert says. This display of recall left Treffert with no doubt that Peek was a savant. Peek’s abilities dazzled screenwriter Barry Morrow when the two men met in 1984 at a committee meeting of the Association for Retarded Citizens. Morrow went on to pen the script for the 1988 film Rain Man, basing Dustin Hoffman’s character on Peek. The concept of savant syndrome dates back to 1887, when physician J. Langdon Down coined the term “idiot savant” for persons who showed low IQ but superlative artistic, musical, mathematical, or other skills. (At the time, the word “idiot” denoted low IQ and was not considered insulting.) Nine months after Peek was born in 1951, a doctor told his family “that Kim was retarded, and they should put him in an institution and forget about him,” says Treffert. “Another doctor suggested a lobotomy, which fortunately they didn’t carry out.” Instead, his parents raised him at home in Utah where he raced through books, memorizing them. Despite his feats of memory and other abilities, such as performing impressive calculations in his head, Peek never learned to carry out many everyday tasks, such as dressing himself. MRIs would later reveal that Peek had abnormalities in the left hemisphere of his brain and was missing a corpus callosum, which controls communication between the two cerebral hemispheres. © 1986–2020 The Scientist

Keyword: Learning & Memory
Link ID: 27251 - Posted: 05.18.2020

By Rachel Love Nuwer The renowned biologist E.O. Wilson once quipped, “When you have seen one bird, you have not seen them all.” The diversity of the world’s 10,000-plus bird species is truly staggering, ranging from 2.5-inch-long hummingbirds that weigh as little as a dime, to 9-foot ostriches that can kick hard enough to kill a human. For decades, though, scientists generally thought of birds as conforming to a single set of rules: Females are drab and silent, while males are flashy and boisterous. Pairs are monogamous, and in the rare event of philandering, the male always initiates. Above all, this thinking posited that all birds are automatons, with pint-sized brains that constrain intelligence. Like many presumptions humans make about nature and other species, the truth turns out to be much more complex and fascinating than we ever imagined, according to science journalist Jennifer Ackerman in “The Bird Way: A New Look at How Birds Talk, Work, Play, Parent, and Think.” A new wave of research is not only dispelling old assumptions and showing that birds do not conform to sweeping generalizations, but also revealing that they are capable of nuanced, highly intelligent behaviors that we once believed to be uniquely human (or at least belonging solely to a few fellow mammals). Ackerman walks readers through the most extreme, surprising, and thought-provoking examples of recently uncovered bird behavior. She draws on hundreds of scientific studies and dozens of interviews and field visits with leading ornithologists to lay out the new revelations, from findings that choughs kidnap and enslave young from other groups (the only record of this disturbing act outside of humans and ants), to the discovery that palm cockatoos build their own musical instruments. The result is a book written for true nature and bird lovers — as well as those interested in the origins of intelligence, sociability, deception, altruism, innovation, language, and many of the other attributes at the heart of what we consider to be human.

Keyword: Intelligence; Evolution
Link ID: 27249 - Posted: 05.16.2020