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How Our Brains Make Memories

How Our Brains Make Memories
Sitting at a sidewalk café in Montreal on a sunny morning, Karim Nader recalls the day eight years earlier when two planes slammed into the twin towers of the World Trade Center. He lights a cigarette and waves his hands in the air to sketch the scene. At the time of the attack, Nader was a postdoctoral researcher at New York University. He flipped the radio on while getting ready to go to work and heard the banter of the morning disc jockeys turn panicky as they related the events unfolding in Lower Manhattan. Nader ran to the roof of his apartment building, where he had a view of the towers less than two miles away. In the following days, Nader recalls, he passed through subway stations where walls were covered with notes and photographs left by people searching desperately for missing loved ones. Like millions of people, Nader has vivid and emotional memories of the September 11, 2001, attacks and their aftermath. Nader believes he may have an explanation for such quirks of memory.

Magnetic manipulation of the sense of morality : Neurophilosophy WHEN making moral judgements, we rely on our ability to make inferences about the beliefs and intentions of others. With this so-called “theory of mind”, we can meaningfully interpret their behaviour, and decide whether it is right or wrong. The legal system also places great emphasis on one’s intentions: a “guilty act” only produces criminal liability when it is proven to have been performed in combination with a “guilty mind”, and this, too, depends on the ability to make reasoned moral judgements. MIT researchers now show that this moral compass can be very easily skewed. Liane Lee Young of MIT’s Department of Brain and Cognitive Science and her colleagues asked participants to make moral judgements about different variations of a number of scenarios. These scenarios differ in the beliefs underlying Grace’s actions and in their outcome. Whether or not these findings extend to real world judgements remains to be seen. Young, L., et al. (2010). Saxe, R. & Kanwisher, N. (2003).

Your Memory Isn't What You Think It Is Who hasn’t experienced something like this with old friends? ‘That was a great day in the park.’ ‘No, it was the beach.’ ‘It rained.’ ‘We wore overcoats.’ It is our friend’s memory that is faulty, not ours we say. Now Daniela Schiller, of Mt. Not only are our memories faulty (anyone who has uncovered old diaries knows that), but more importantly Schiller says our memories change each time they are recalled. Schiller says that memories are malleable constructs that are reconstructed with each recall. What we remember changes each time we recall the event. One implication of Schiller’s work is that memory isn’t like a file in our brain but more like a story that is edited every time we tell it. Schiller says, “My conclusion is that memory is what you are now. In his MIT Technology Review article about this work, Stephen S.

Increased Interstitial White Matter Neuron Density in the Dorsolateral Prefrontal Cortex of People with Schizophrenia To view the full text, please login as a subscribed user or purchase a subscription. Click here to view the full text on ScienceDirect. Figure 1 Neuronal nuclear antigen (NeuN)–positive neurons (A) below grey matter (grey matter/white matter border represented by dotted line). Figure 2 Density of neuronal nuclear antigen + immunopositive interstitial white matter (neurons/mm2) in (A) superficial white matter and (B) deep white matter in control subjects (squares) and schizophrenic cases (triangles). Figure 3 Superficial neuronal nuclear antigen immunopositive interstitial white matter neuron (IWMN) density (neurons/mm2) negatively correlates with gray matter somatostatin (SST) expression in control subjects and schizophrenia cases (control, squares; schizophrenia, triangles). qPCR, quantitative polymerase chain reaction. Figure 4 Representative in situ hybridization images showing somatostatin (SST) mRNA signals in control (A, C) and schizophrenia (B, D) subjects. Figure 5 Figure 6 Background

Memories Can Be Distorted Over Time September 20, 2012 Connie K. Ho for redOrbit.com — Your Universe Online Researchers from the Feinberg School of Medicine at Northwestern University recently discovered that a memory of an event can change with each retelling. The team of scientists found that the modification of the memory of an event is due to an adjustment in brain networks that changes the placement of the memory. As a result, when an individual remembers a particular situation, it may not be exactly the same as remembered before. “A memory is not simply an image produced by time traveling back to the original event — it can be an image that is somewhat distorted because of the prior times you remembered it,” explained lead author Donna Bridge, a postdoctoral fellow at Northwestern University Feinberg School of Medicine, in a prepared statement. The results of the study may pinpoint some of the issues that witnesses may have when giving a testimony for a trial. Source: Connie K.

brainSCANr Scans reveal how we change memories › News in Science (ABC Science) News in Science Friday, 1 July 2011 Clare PainABC Changing memories Reminiscing about old times with your friends is fun, but it may rewrite history according to a new study. Research reported in this week's edition of the journal Science suggests that comparing memories with other people sometimes alters the stored memory in the brain. Micah Edelson, a PhD student, and Professor Yadin Dudai at the Weizmann Institute of Science in Israel carried out the work with scientists from University College London in the United Kingdom. It has been known for some time that, when people reminisce in a group, an error in memory held by one group member may be transferred to others in the group. Sometimes, people genuinely believe the new erroneous version of events, a process known as 'rewriting'. "Humans are very social animals," says Edelson. Edelson divided 30 volunteers into small groups to watch a TV documentary. Changes in the brain Not always a bad thing

Phantoms in the Brain The writings of Oliver Sacks and others have shown us that we can learn much about ourselves by looking closely at the deficits shown by people with neurological problems. V.S. Ramachandran has seen countless patients suffering from anosognosia, phantom limb pain, blindsight, and other disorders, and he brings a remarkable mixture of clinical intuition and research savvy to bear on their problems. He is one of the few scientists who are able and willing to explore the personal, subjective ramifications of his work; he rehumanizes an often too-sterile field and captures the spirit of wonder so essential for true discovery. Phantoms in the Brain is equal parts medical mystery, scientific adventure, and philosophical speculation. Watch the full documentary now (playlist - 1 hour, 39 minutes)

How Much of Your Memory Is True? Meanwhile, doubts about the standard theory of memory were piling up in the world outside the neuroscience lab. In the early 1990s many people began reporting what seemed to be long-buried memories of childhood sexual abuse. These traumatic recollections frequently surfaced with the help of recovered-memory therapy techniques like hypnosis and guided imagery, in which patients are encouraged to visualize terrible experiences. Cognitive scientists suspected that some of these memories were bogus, the unwitting product of suggestion by the therapist. Spurred on by the controversy over recovered memory, other cognitive scientists found that false memory is a normal phenomenon. Even harrowing memories—the so-called flashbulb memories that feel as if they have been permanently seared into the brain—are not as accurate as we think. Rewriting the PastIn the hierarchy of memory science, Karim Nader hardly ranked—a lowly postdoc, only 33 years old, and not even a memory researcher.

How Alcohol Affects the Brain General Effects of Alcohol on the Brain Alcohol can affect several parts of the brain, but in general, alcohol contracts brain tissue and depresses the central nervous system. Also, alcohol destroys brain cells and unlike many other types of cells in the body, brain cells do not regenerate. Excessive drinking over a prolonged period of time can cause serious problems with cognition and memory. When alcohol reaches the brain, it interferes with communication between nerve cells, by interacting with the receptors on some cells. Chemical Effects of Alcohol on the Brain To understand how alcohol interferes with brain function, it is necessary to know a little bit about normal brain function. The gap between cells where neurotransmitters are active is called the synapse. When alcohol is introduced to the synapse, the normal neurotransmission may be affected. Effects of Alcohol on Brain Parts Alcohol affects different parts of the brain in different ways. The cerebral cortex and alcohol

Topic of Daydreams Determine Memory Loss By Rick Nauert PhD Senior News Editor Reviewed by John M. Grohol, Psy.D. on July 27, 2010 Have you ever found yourself daydreaming and had difficulty remembering what you were doing before the temporary escape? If the answer is yes, then you are normal. Psychologists have known for a while that context is important to remembering. Previous studies had also found that thinking about something else — daydreaming or mind-wandering — blocks access to memories of the recent past. In the new study, psychological scientists wanted to know if the content of your daydreams affects your ability to access a recently acquired memory. For one experiment, each participant looked at a list of words as they appeared on a computer screen, one at a time. Next, the participant was shown a second list of words. Participants who had thought about the place they’d been only a few hours before remembered more of the words from the first list than did participants who had thought back several weeks.

Subliminal Stimuli Explained Subliminal Articles There is a lot of misunderstanding about the term subliminal and how subliminal messages, especially those found a subliminal CDs, work. Subliminal messages are not just verbal commands. They can take the form of a single hidden word, entire sentences or even images which elicit an emotional response at a subconscious level. The word "subliminal" is used to refer to anything that is registered by the brain but is only offered to the senses below the threshold of conscious perception. Subliminal stimuli refers to anything that stimulations the brain and senses at a subliminal level. For example an image may be shown so quickly to an individual that all he or she is consciously aware of is a flash of light or imperceptible image. Likewise a verbal message may also be hidden, or "masked", behind other sounds so that the words being spoken are imperceptible. So how does a subliminal stimulus affect the brain and behaviour of those that are exposed to them?

Do Brain Exercises Prevent Memory Loss? By Rick Nauert PhD Senior News Editor Reviewed by John M. Grohol, Psy.D. on February 18, 2009 The debated issue of whether brain activities can prevent memory loss continues be a hot topic. A just released study supports the value of participating in certain mental activities. The study suggests activities like reading magazines or crafting in middle age or later in life may delay or prevent memory loss. Investigators studied 197 people between the ages of 70 and 89 with mild cognitive impairment, or diagnosed memory loss, and 1,124 people that age with no memory problems. Both groups answered questions about their daily activities within the past year and in middle age, when they were between 50 to 65 years old. People who watched television for less than seven hours a day in later years were 50 percent less likely to develop memory loss than people who watched for more than seven hours a day. “This study is exciting because it demonstrates that aging does not need to be a passive process.

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