People have more difficulty recalling the string of letters BIC, IAJ, FKI, RSU and SAF than FBI, CIA, JFK, IRS and USA. New research by Carnegie Mellon University (CMU) psychologists takes this learning principle one step further by uncovering how the strength -- or familiarity -- of those chunks plays a crucial role. CMU researchers show for the first time that it is easier to learn new facts that are composed of more familiar chunks. These findings have implications for how students are taught almost any subject, including second language learning. They also indicate that the long-held belief that children have less working memory than adults may not be true because working memory resources are more rapidly consumed when the chunks are less familiar. "We are suggesting that working memory capacity is not a fixed quantity but interacts with the familiarity of the elements that need to be processed. If everything is very familiar, it is easy to comprehend and build new knowledge. If all of the components are unfamiliar, the task becomes very difficult or impossible," said Lynne Reder, professor of psychology in the Dietrich College of Humanities and Social Sciences and a leading expert on memory, cognition and behavior. Reder also is a member of CMU's Center for the Neural Basis of Cognition (CNBC) and the Human-Computer Interaction Institute. "This work has implications for how to optimize instruction, specifically that concepts should be introduced to students in a way that they have a good grasp and familiarity with those concepts before trying to combine them into more complex informational structures. These findings may also help to explain certain paradoxes such as why children tend to learn computer applications more easily than adults and may help to explain why they learn second languages better than adults," Reder said. "Little kids may actually have more working memory than adults. They often appear to have less only because they have fewer knowledge chunks and those chunks are weaker than adults. Adults have wisdom 'knowledge and skills -- and scientists have been confusing that with greater working memory," she said. Lynne M. Reder, Xiaonan L. Liu, Alexander Keinath, Vencislav Popov. Building knowledge requires bricks, not sand: The critical role of familiar constituents in learning. Psychonomic Bulletin & Review, 2015
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The brain’s foundation, frame, and walls are built in the womb. As an embryo grows into a fetus, some of its dividing cells turn into neurons, arranging themselves into layers and forming the first synapses, the organ’s electrical wiring. Four or five months into gestation, the brain’s outermost layer, the cerebral cortex, begins to develop its characteristic wrinkles, which deepen further after birth. It isn’t until a child’s infant and toddler years that the structures underlying higher-level cognition—will power, emotional self-control, decision-making—begin to flourish; some of them continue to be fine-tuned throughout adolescence and into the first decade of adulthood. Dr. Pat Levitt, a developmental neuroscientist at Children’s Hospital Los Angeles, he has become interested in another sort of neurotoxin: poverty. As it turns out, the conditions associated with poverty — “overcrowding, noise, substandard housing, separation from parent(s), exposure to violence, family turmoil,” and other forms of extreme stress--can be toxic to the developing brain, just like drug or alcohol abuse. These conditions provoke the body to release hormones such as cortisol, which is produced in the adrenal cortex. Brief bursts of cortisol can help a person manage difficult situations, but high stress over the long term can be disastrous. In a pregnant woman, the hormone can “get through the placenta into the fetus,” Levitt told me, potentially influencing her baby’s brain and tampering with its circuitry. Later, as the same child grows up, cortisol from his own body may continue to sabotage the development of his brain. New research shows that the more people think they know about a topic, the more likely they are to state facts that are completely false — a process called "over-claiming," according to the study, published in Psychological Science. For the study, researchers designed a series of experiments to assess people's claims to knowledge, with the goal of seeing how people perceived their own knowledge. In one set of experiments, for example, researchers tested whether participants who believed they were experts in personal finance would be more likely to claim they knew about "fake" financial terms. One hundred participants were asked to rate their knowledge of personal finance in addition to noting how familiar they were with 15 financial terms. Most of these terms were real, such as inflation and home equity. But there were also made-up terms, such as "pre-rated stocks" and "annualized credit," which were intended to blend in with the rest. As the researchers predicted, those who believed they knew the most about finance were the most likely to claim they knew what the fake terms were. "The more people believed they knew about finances in general, the more likely they were to over-claim knowledge of the fictitious financial terms," said Stav Atir, study author and psychological scientist at Cornell University, in a statement. Some children recover more slowly from concussion and other types of traumatic brain injury because they have extensive damage to the protective coating around brain nerve fibers, a new study says. Researchers looked at 32 patients, aged 8 to 19, who had suffered a moderate to severe brain injury in the previous five months. The kids underwent tests to assess how fast they could process and recall information. The researchers also recorded electrical activity in the patients' brains to determine how quickly their brain nerve fibers could transmit information. And imaging scans assessed the structural condition of the youngsters' brain wiring. "Just as electricians insulate electrical wires to shield their connections, the brain's nerve fibers are encased in a fatty tissue called myelin that protects signals as they travel across the brain," Dr. Christopher Giza, a professor of pediatrics and neurosurgery at the University of California, Los Angeles, explained in a university news release. "We suspected that trauma was damaging the myelin and slowing the brain's ability to transmit information, interfering with patients' capacity to learn," he explained. Half of the patients had widespread damage to the myelin. They did 14 percent worse on the mental skills tests, and their brain wiring worked three times more slowly than healthy children. The other 16 brain injury patients had nearly intact myelin. Their brains processed information as quickly as healthy children, and they did 9 percent better on the mental skills tests than those with more myelin damage. The study, published in the July 15 issue of the Journal of Neuroscience, offers possible indicators that doctors could use to identify higher-risk brain injury patients who require closer monitoring, the researchers said. Traumatic brain injury is the single most common cause of death and disability in American children and teens, according to the U.S. Centers for Disease Control. Through this free app and a simple printed image, Anatomy 4D transports students, teachers, medical professionals, and anyone who wants to learn about the body into an interactive 4D experience of human anatomy. Visually stunning and completely interactive, Anatomy 4D uses augmented reality and other cutting edge technologies to create the perfect vehicle for 21st century education.
Researchers at MIT have proven that the brain’s cortex doesn’t process specific tasks in highly specialized modules — showing that the cortex is, in fact, quite dynamic when sharing information. Previous studies of the brain have depicted the cortex as a patchwork of function-specific regions. Parts of the visual cortex at the back of the brain, for instance, encode color and motion, while specific frontal and middle regions control more complex functions, such as decision-making. Neuroscientists have long criticized this view as too compartmentalized. In this new study, the researchers built an array of 108 electrodes that measured neural spikes in 2,694 sites across six cortical regions that are thought to control specific functions. Multiple cortical regions work together simultaneously to process sensorimotor information — sensory input coupled with related actions — despite their predetermined specialized roles. “Some areas may process motion more than color, some may process color more than motion, and sometimes you can see the information rising up in one area before the other,” Miller says. “But generally information is distributed all over the cortex.” Of particular note, Miller adds, was how widely the executive “choice” signals — deciding which direction to move their eyes — were distributed across the cortex. Previously, it was thought that decisions rise solely in specific cortical areas. “But you see the decision percolating up all over many parts of the cortex simultaneously, so even decision-making is more of an emerging property of many cortical areas,” he says. In providing a better understanding of the cortex’s sensorimotor processing, Miller says, the study may open doors for broader use of noninvasive treatments for stroke recovery, which deliver electrical pulses to increase brain waves in damaged cortical areas to restore sensory or motor functions. For the study, Dr. Munro Cullum, a neuropsychologist at the University of Texas Southwestern Medical Center in Dallas, and his colleagues collected data on 28 former NFL players, aged 63 and older. Eight suffered from memory and attention problems and had a history of concussion. Seventeen had a history of concussion with loss of consciousness. Researchers found that former players with a history of concussion but who showed no problems with memory and learning had normal but lower scores on a test of verbal memory compared with a control group of people who had no history of concussion or football. Former players with memory problems and a history of concussion did worse on the memory tests than people without a history of concussion or athletes without memory problems, the researchers found. However, retired football players who had at least one concussion with loss of consciousness had a smaller hippocampus compared with retired players who never had a concussion or people who never suffered a concussion or played football. Dr. Cullum noted that a concussion with loss of consciousness may increase the risk for memory problems beyond the normal risk associated with an aging brain. Dr. Robert Glatter, director of sports medicine and traumatic brain injury at Lenox Hill Hospital in New York City, said, "We are now beginning to understand that repetitive hits to the brain over time -- without concussion or loss of consciousness -- can be an important marker for mental impairment and memory loss and potentially other neurodegenerative disease such as dementia or Alzheimer's," he said. Dr. Robert Duarte, a neurologist and concussion expert at North Shore-LIJ's Cushing Neuroscience Institute in Manhasset, N.Y., agreed that losing consciousness isn't necessary to cause brain damage that can lead to memory problems. "We see that people who have several mild concussions over time also have a decrease in hippocampal volume," he said. SOURCES: C. Munro Cullum, Ph.D., neuropsychologist, University of Texas Southwestern Medical Center, Dallas; Robert Glatter, M.D., director, sports medicine and traumatic brain injury, Lenox Hill Hospital, New York City; Robert Duarte, M.D., neurologist and concussion expert, North Shore-LIJ's Cushing Neuroscience Institute, Manhasset, N.Y.; May 18, 2015, JAMA Neurology. This site contains short talks on the different scientific methods we can use to study the human mind and brain, and some of the cool things we have learned so far. You do not need any background in the field to understand the talks. For an overall introduction, watch my TED talk. To get started, watch the talks within each topic in order, browse at random, or just jump in here.
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