Chapter 14. Attention and Consciousness

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By Tam Hunt How do you know your dog is conscious? Well, she wags her tail when she’s happy, bounces around like a young human child when excited, and yawns when sleepy— among many other examples of behaviors that convince us (most of us, at least) that dogs are quite conscious in ways that are similar to, but not the same as, human consciousness. Most of us are okay attributing emotions, desires, pain and pleasure—which is what I mean by consciousness in this context—to dogs and many other pets. What about further down the chain. Is a mouse conscious? We can apply similar tests for “behavioral correlates of consciousness” like those I’ve just mentioned, but, for some of us, the mice behaviors observed will be considerably less convincing than for dogs in terms of there being an inner life for the average mouse. Advertisement What about an ant? What behaviors do ants engage in that might make us think an individual ant is at least a little bit conscious? Or is it not conscious at all? Let me now turn the questions around: how do I know you, my dear reader, are conscious? If we met, I’d probably introduce myself and hear you say your name and respond to my questions and various small talk. You might be happy to meet me and smile or shake my hand vigorously. Or you might get a little anxious at meeting someone new and behave awkwardly. All of these behaviors would convince me that you are in fact conscious much like I am, and not just faking it! Now here’s the broader question? How can we know anybody or any animal or any thing is actually conscious and not just faking it? The nature of consciousness makes it by necessity a wholly private affair. The only consciousness I can know with certainty is my own. Everything else is inference. © 2019 Scientific American

Keyword: Consciousness
Link ID: 26557 - Posted: 08.31.2019

By Anil K. Seth On the 10th of April this year Pope Francis, President Salva Kiir of South Sudan and former rebel leader Riek Machar sat down together for dinner at the Vatican. They ate in silence, the start of a two-day retreat aimed at reconciliation from a civil war that has killed some 400,000 people since 2013. At about the same time in my laboratory at the University of Sussex in England, Ph.D. student Alberto Mariola was putting the finishing touches to a new experiment in which volunteers experience being in a room that they believe is there but that is not. In psychiatry clinics across the globe, people arrive complaining that things no longer seem “real” to them, whether it is the world around them or their own selves. In the fractured societies in which we live, what is real—and what is not—seems to be increasingly up for grabs. Warring sides may experience and believe in different realities. Perhaps eating together in silence can help because it offers a small slice of reality that can be agreed on, a stable platform on which to build further understanding. Advertisement We need not look to war and psychosis to find radically different inner universes. In 2015 a badly exposed photograph of a dress tore across the Internet, dividing the world into those who saw it as blue and black (me included) and those who saw it as white and gold (half my lab). Those who saw it one way were so convinced they were right—that the dress truly was blue and black or white and gold—that they found it almost impossible to believe that others might perceive it differently. We all know that our perceptual systems are easy to fool. The popularity of visual illusions is testament to this phenomenon. Things seem to be one way, and they are revealed to be another: two lines appear to be different lengths, but when measured they are exactly the same; we see movement in an image we know to be still. The story usually told about illusions is that they exploit quirks in the circuitry of perception, so that what we perceive deviates from what is there. Implicit in this story, however, is the assumption that a properly functioning perceptual system will render to our consciousness things precisely as they are. © 2019 Scientific American

Keyword: Consciousness; Vision
Link ID: 26549 - Posted: 08.29.2019

By John Horgan At the beginning of my book Mind-Body Problems, I describe one of my earliest childhood memories: I am walking near a river on a hot summer day. My left hand grips a fishing rod, my right a can of worms. One friend walks in front of me, another behind. We’re headed to a spot on the river where we can catch perch, bullheads and large-mouth bass. Weeds bordering the path block my view of the river, but I can smell its dank breath and feel its chill on my skin. The seething of cicadas builds to a crescendo. I stop short. I’m me, I say. My friends don’t react, so I say, louder, I’m me. The friend before me glances over his shoulder and keeps walking, the friend behind pushes me. I resume walking, still thinking, I’m me, I’m me. I feel lonely, scared, exhilarated, bewildered. Advertisement That moment was when I first became self-conscious, aware of myself as something weird, distinct from the rest of the world, demanding explanation. Or so I came to believe when I recalled the incident in subsequent decades. I never really talked about it, because it was hard to describe. It meant a lot to me, but I doubted it would mean much to anyone else. Then I learned that others have had similar experiences. One is Rebecca Goldstein, the philosopher and novelist, whom I profiled in Mind-Body Problems. Before interviewing Goldstein, I read her novel 36 Arguments for the Existence of God, and I came upon a passage in which the hero, Cass, a psychologist, recalls a recurrent “metaphysical seizure” or “vertigo” that struck him in childhood. Lying in bed, he was overcome by the improbability that he was just himself and no one else. “The more he tried to get a fix on the fact of being Cass here,” Goldstein writes, “the more the whole idea of it just got away from him.” Even as an adult, Cass kept asking himself, “How can it be that, of all things, one is this thing, so that one can say, astonishingly, ‘Here I am’”? © 2019 Scientific American

Keyword: Consciousness; Development of the Brain
Link ID: 26510 - Posted: 08.17.2019

Patti Neighmond Most children enrolled in Medicaid who get a diagnosis of attention deficit hyperactivity disorder don't get timely or appropriate treatment afterward. That's the conclusion of a report published Thursday by a federal watchdog agency, the Department of Health and Human Services' Office of Inspector General. "Nationwide, there were 500,000 Medicaid-enrolled children newly prescribed an ADHD medication who did not receive any timely follow-up care," says Brian Whitley, a regional inspector general with OIG. The report analyzed Medicaid claims data from 2014 and 2015. Those kids didn't see a health care provider regarding their ADHD within a month of being prescribed the medication, though pediatric guidelines recommend that, he says. And one in five of those children didn't get the two additional check-ins with a doctor they should get within a year. "That's a long time to be on powerful medications without a practitioner checking for side effects or to see how well the medication is working," Whitley says. Additionally, according to the OIG report, "Nearly half of Medicaid-enrolled children who were newly prescribed an ADHD medication did not receive behavioral therapy," though that, too, is recommended by pediatricians. Elizabeth Cavey, who lives with her family in Arlington, Va., knows just how important it is to get a child with ADHD accurately diagnosed and treated. Kindergarten, Cavey says, was a disaster for her daughter. "She was constantly being reprimanded and forced to sit still," Cavey recalls. "And she's a bright child, but she kept falling further and further behind in learning letters and language, because she could not concentrate." © 2019 npr

Keyword: ADHD; Development of the Brain
Link ID: 26500 - Posted: 08.15.2019

Meredith Fore A long-standing controversy in neuroscience centers on a simple question: How do neurons in the brain share information? Sure, it’s well-known that neurons are wired together by synapses and that when one of them fires, it sends an electrical signal to other neurons connected to it. But that simple model leaves a lot of unanswered questions—for example, where exactly in neurons’ firing is information stored? Resolving these questions could help us understand the physical nature of a thought. Two theories attempt to explain how neurons encode information: the rate code model and the temporal code model. In the rate code model, the rate at which neurons fire is the key feature. Count the number of spikes in a certain time interval, and that number gives you the information. In the temporal code model, the relative timing between firings matters more—information is stored in the specific pattern of intervals between spikes, vaguely like Morse code. But the temporal code model faces a difficult question: If a gap is "longer" or "shorter," it has to be longer or shorter relative to something. For the temporal code model to work, the brain needs to have a kind of metronome, a steady beat to allow the gaps between firings to hold meaning. Every computer has an internal clock to synchronize its activities across different chips. If the temporal code model is right, the brain should have something similar. Some neuroscientists posit that the clock is in the gamma rhythm, a semiregular oscillation of brain waves. But it doesn’t stay consistent. It can speed up or slow down depending on what a person experiences, such as a bright light. Such a fickle clock didn't seem like the full story for how neurons synchronize their signals, leading to ardent disagreements in the field about whether the gamma rhythm meant anything at all. © 2018 Condé Nast.

Keyword: Consciousness; Biological Rhythms
Link ID: 26494 - Posted: 08.13.2019

Hope Reese Patricia S. Churchland is a key figure in the field of neurophilosophy, which employs a multidisciplinary lens to examine how neurobiology contributes to philosophical and ethical thinking. In her new book, “Conscience: The Origins of Moral Intuition,” Churchland makes the case that neuroscience, evolution, and biology are essential to understanding moral decision-making and how we behave in social environments. In the past, “philosophers thought it was impossible that neuroscience would ever be able to tell us anything about the nature of the self, or the nature of decision-making,” the author says. The way we reach moral conclusions, Churchland asserts, has a lot more to do with our neural circuitry than we realize. The way we reach moral conclusions, she asserts, has a lot more to do with our neural circuitry than we realize. We are fundamentally hard-wired to form attachments, for instance, which greatly influence our moral decision-making. Also, our brains are constantly using reinforcement learning — observing consequences after specific actions and adjusting our behavior accordingly. Churchland, who teaches philosophy at the University of California, San Diego, also presents research showing that our individual neuro-architecture is heavily influenced by genetics: political attitudes, for instance, are 40 to 50 percent heritable, recent scientific studies suggest. Copyright 2019 Undark

Keyword: Consciousness; Emotions
Link ID: 26480 - Posted: 08.02.2019

Bruce Bower Monkeys can keep strings of information in order by using a simple kind of logical thought. Rhesus macaque monkeys learned the order of items in a list with repeated exposure to pairs of items plucked from the list, say psychologist Greg Jensen of Columbia University and colleagues. The animals drew basic logical conclusions about pairs of listed items, akin to assuming that if A comes before B and B comes before C, then A comes before C, the scientists conclude July 30 in Science Advances. Importantly, rewards given to monkeys didn’t provide reliable guidance to the animals about whether they had correctly ordered pairs of items. Monkeys instead worked out the approximate order of images in the list, and used that knowledge to make choices in experiments about which of two images from the list followed the other, Jensen’s group says. Previous studies have suggested that a variety of animals, including monkeys, apes, pigeons, rats and crows, can discern the order of a list of items (SN: 7/5/08, p. 13). But debate persists about whether nonhuman creatures do so only with the prodding of rewards for correct responses or, at least sometimes, by consulting internal knowledge acquired about particular lists. Jensen’s group designed experimental sessions in which four monkeys completed as many as 600 trials to determine the order of seven images in a list. Images included a hot air balloon, an ear of corn and a zebra. Monkeys couldn’t rely on rewards to guide their choices. In some sessions, animals usually received a larger reward for correctly identifying which of two images came later in the list and a smaller reward for an incorrect response. In other sessions, incorrect responses usually yielded a larger reward than correct responses. Rewards consisted of larger or smaller gulps of water delivered through tubes to the moderately thirsty primates. |© Society for Science & the Public 2000 - 2019

Keyword: Attention; Evolution
Link ID: 26475 - Posted: 08.01.2019

By Christof Koch “Consciousness” refers to any subjective experience — the delectable taste of Nutella, the sharp sting of an infected tooth, the slow passage of time when bored, the sense of vitality and anxiety just before a competitive event. In the words of the philosopher Thomas Nagel, consciousness exists in a human or other subject whenever “there is something it is like to be that organism.” The concept has inspired countless philosophical theories since antiquity and much laboratory work over the past century, but it has also given rise to many misunderstandings. Myth No. 1 Humans have a unique brain. There’s a long history of scientists thinking they have identified a particular feature to explain our advanced consciousness (and planetary dominance). In a popular TED talk, the neuroscientist Suzana Herculano-Houzel argues that the human brain’s distinctiveness lies in the huge number of neurons that make up the outermost layer of the organ, the cerebral cortex (or neocortex): 16 billion, out of some 86 billion total neurons. “That’s the simplest explanation for our remarkable cognitive abilities,” she says. Other suppositions have included special brain regions or nerve cells found only (or primarily) in humans — spindle or von Economo neurons, for example. Or perhaps the human brain consumes more calories than the brains of other species? After close to two centuries of brain research, however, no single feature of the human brain truly stands out. We certainly do not possess the largest brain — elephants and whales trounce us. Recent research has revealed that pilot whales, a type of dolphin, have 37 billion cortical neurons, undermining Herculano-Houzel’s hypothesis. And researchers have found that whales, elephants and other large-brained animals (not just great apes and humans) also have von Economo neurons. New research shows that humans and mice have about the same number of categories of brain cells. The fact is, there is no simple brain-centric explanation for why humans sit atop the cognitive hill. © 1996-2019 The Washington Post

Keyword: Consciousness
Link ID: 26467 - Posted: 07.30.2019

By Jocelyn Kaiser U.S. scientists who challenged a new rule that would require them to register their basic studies of the human brain and behavior in a federal database of clinical trials have won another reprieve. The National Institutes of Health (NIH) in Bethesda, Maryland, says it now understands why some of that kind of research won’t easily fit the format of ClinicalTrials.gov, and the agency has delayed for the reporting requirements for another 2 years. The controversy dates back to 2017, when behavioral and cognitive researchers realized that new requirements for registering and reporting results from NIH-funded clinical studies would also cover even basic studies of human subjects, experiments that did not test drugs or other potential treatments. The scientists protested that including such studies would confuse the public and create burdensome, unnecessary paperwork. A year ago, NIH announced it would delay the requirement until September and seek further input. The responses prompted NIH staff to examine published papers from scientists conducting basic research. They agreed it would be hard to include some of these studies into the rigid informational format used by ClinicalTrials.gov—for example, because the authors didn’t specify the outcome they expected before the study began, or they reported results for individuals and not the whole group. In other cases, the authors did several preliminary studies to help them design their experiment. © 2019 American Association for the Advancement of Science

Keyword: Attention; Learning & Memory
Link ID: 26450 - Posted: 07.25.2019

By Diana Kwon Your brain is a bit like a concert hall. To drive our cognitive processes, several groups of neurons need to become active—and, like the various sections of an orchestra, work in harmony to produce the symphony of computations that allow us to perceive and interact with our surroundings. As with an orchestra, the brain likely requires a conductor to keep all its active parts in sync. There are neuroscientists who think that gamma rhythms, fast brain waves that fluctuate at a frequency of approximately 40 cycles per second, play this role. By ticking at regular intervals, these oscillations are thought to act like a clock that coordinates information transfer from one group of neurons to another. There is ample evidence suggesting that gamma waves are important for the brain's computations: decades of studies in humans and other animals have found these patterns in many parts of brain and have associated them with a range of cognitive processes, such as attention and the mental scratchpad of working memory. Some studies have even linked disturbances in these oscillations to various neurological diseases, including schizophrenia and Alzheimer's. But a consensus does not exist. Some neuroscientists think that these gamma waves may not do much at all. Rather than a relevant physiological signal, one camp believes that these rhythms are simply “an exhaust fume of computation,” says Chris Moore, a neuroscientist at the Carney Institute for Brain Science at Brown University. In the same way your car releases emissions each time you drive it—the gamma signal could be perfectly correlated with brain activity, but not provide any meaningful contribution to the actual function of the car, he explains. © 2019 Scientific American

Keyword: Biological Rhythms; Attention
Link ID: 26429 - Posted: 07.19.2019

By Ryan D'Agostino If you have a son, you have a one-in-seven chance that he has been diagnosed with ADHD. If you have a son who has been diagnosed, it's more than likely that he has been prescribed a stimulant—the most famous brand names are Ritalin and Adderall; newer ones include Vyvanse and Concerta—to deal with the symptoms of that psychiatric condition. The Drug Enforcement Administration classifies stimulants as Schedule II drugs, defined as having a "high potential for abuse" and "with use potentially leading to severe psychological or physical dependence." (According to a University of Michigan study, Adderall is the most abused brand-name drug among high school seniors.) In addition to stimulants like Ritalin, Adderall, Vyvanse, and Concerta, Schedule II drugs include cocaine, methamphetamine, Demerol, and OxyContin. According to manufacturers of ADHD stimulants, they are associated with sudden death in children who have heart problems, whether those heart problems have been previously detected or not. They can bring on a bipolar condition in a child who didn't exhibit any symptoms of such a disorder before taking stimulants. They are associated with "new or worse aggressive behavior or hostility." They can cause "new psychotic symptoms (such as hearing voices and believing things that are not true) or new manic symptoms." They commonly cause noticeable weight loss and trouble sleeping. In some children, some stimulants can cause the paranoid feeling that bugs are crawling on them. Facial tics. They can cause children's eyes to glaze over, their spirits to dampen. One study reported fears of being harmed by other children and thoughts of suicide. ©2019 Hearst Magazine Media, Inc.

Keyword: ADHD; Drug Abuse
Link ID: 26420 - Posted: 07.15.2019

By Stephen L. Macknik When Susana Martinez-Conde and I talk to audiences about NeuroMagic—our research initiative to study the brain with magic (and vice-versa), people often ask us how we bring both fields together. They want to know in what ways magic tricks can inform neuroscience, and what a day in the life of a neuromagic scientist looks like. How do we run a neuromagic experiment, from collecting the data to using the results to gain knowledge about the mind's inner secrets? Our new study, led by Anthony Barnhart (aka Magic Tony) and just published in the Journal of Eye Movement Research, illustrates some of the ways in which we investigate magic in the lab. You can download the paper for free, but as it is written for academics, I'll give you the gist here. The experiment addresses how various neural circuits interact in your brain while you watch a magic performance. There's the visual system—critical for perception—there's the oculomotor system—critical for targeting and moving the eyes—and there's the attentional system—critical for filtering out irrelevant information and allowing you to literally and figuratively focus both the visual and oculomotor systems at the right place and at the right time. Without all three of these systems working together, you would be unable to conduct most visual tasks. Advertisement Magic is one of the inroads available to dissect the function of many perceptual and cognitive systems, and especially so in situations that are fairly similar to those we encounter in real life. This concept—ecological validity—is important to testing whether neuroscience theories will hold up outside of the lab, and one of the reasons why magic tricks are attractive for studying everyday perception and cognition. © 2019 Scientific American

Keyword: Vision; Attention
Link ID: 26412 - Posted: 07.13.2019

By Susana Martinez-Conde Is your mind—every sensation, feeling, and memory you’ve ever had—completely tractable to your brain? If so, does it mean that you are a mere machine, and that all meaning and purpose is illusory? About a year ago, I joined author of Aping Mankind Raymond Tallis, and German philosopher and author of I am Not a Brain Markus Gabriel to discuss these issues at the How the Light Gets In Festival, hosted by the Institute of Art and Ideas. The video of the debate, which you can watch below, just came live last month. My co-panelists and I were tasked to start the debate with short pitches stating our positions on whether our minds and consciousness are no more than matter and mechanism. Specifically, we were charged with answering three questions at the outset, in 4 minutes or less: Are our minds just our brains? Has neuroscience led philosophy astray? Do we need to create new concepts, or abandon old ones, to understand why we feel a sense of meaning? The script that I prepared to address them follows below—but make sure to check out the full video for alternative views, and the discussion that ensued! A lot of the research we do in my lab focuses on understanding the neural bases of illusory perception. About 10 years ago, this led to my becoming interested in the neuroscience of stage magic, and beginning a research program about why magic works in the brain. Along the way, I decided to take magic lessons myself, to get a better understanding of magic: not only as a scientist looking in from the outside, but from the perspective of the magician. This was not only a good research investment, but also a whole lot of fun. But when I tell people about it, a question I get often is, do I still enjoy magic shows, or do they now feel mundane and unmagical? I always answer that I now enjoy magic a lot more than before I started studying it. © 2019 Scientific American

Keyword: Consciousness
Link ID: 26396 - Posted: 07.08.2019

Maria Temming A new analysis of brain scans may explain why hyperrealistic androids and animated characters can be creepy. By measuring people’s neural activity as they viewed pictures of humans and robots, researchers identified a region of the brain that seems to underlie the “uncanny valley” effect — the unsettling sensation sometimes caused by robots or animations that look almost, but not quite, human (SN Online: 11/22/13). Better understanding the neural circuitry that causes this feeling may help designers create less unnerving androids. In research described online July 1 in the Journal of Neuroscience, neuroscientist Fabian Grabenhorst and colleagues took functional MRI scans of 21 volunteers during two activities. In each activity, participants viewed pictures of humans, humanoid robots of varying realism and — to simulate the appearance of hyperrealistic robots — “artificial humans,” pictures of people whose features were slightly distorted through plastic surgery and photo editing. In the first activity, participants rated each picture on likability and how humanlike the figures appeared. Next, participants chose between pairs of these pictures, based on which subject they would rather receive a gift from. In line with the uncanny valley effect, participants generally rated more humanlike candidates as more likable, but this trend broke down for artificial humans — the most humanlike of the nonhuman options. A similar uncanny valley trend emerged in participants’ judgments about which figures were more trustworthy gift-givers. |© Society for Science & the Public 2000 - 2019.

Keyword: Attention; Emotions
Link ID: 26387 - Posted: 07.04.2019

By Matthew Shaer A few years ago, a scientist named Nenad Sestan began throwing around an idea for an experiment so obviously insane, so “wild” and “totally out there,” as he put it to me recently, that at first he told almost no one about it: not his wife or kids, not his bosses in Yale’s neuroscience department, not the dean of the university’s medical school. Like everything Sestan studies, the idea centered on the mammalian brain. More specific, it centered on the tree-shaped neurons that govern speech, motor function and thought — the cells, in short, that make us who we are. In the course of his research, Sestan, an expert in developmental neurobiology, regularly ordered slices of animal and human brain tissue from various brain banks, which shipped the specimens to Yale in coolers full of ice. Sometimes the tissue arrived within three or four hours of the donor’s death. Sometimes it took more than a day. Still, Sestan and his team were able to culture, or grow, active cells from that tissue — tissue that was, for all practical purposes, entirely dead. In the right circumstances, they could actually keep the cells alive for several weeks at a stretch. When I met with Sestan this spring, at his lab in New Haven, he took great care to stress that he was far from the only scientist to have noticed the phenomenon. “Lots of people knew this,” he said. “Lots and lots.” And yet he seems to have been one of the few to take these findings and push them forward: If you could restore activity to individual post-mortem brain cells, he reasoned to himself, what was to stop you from restoring activity to entire slices of post-mortem brain? © 2019 The New York Times Company

Keyword: Consciousness
Link ID: 26380 - Posted: 07.02.2019

By Max Bertolero, Danielle S. Bassett | Networks pervade our lives. Every day we use intricate networks of roads, railways, maritime routes and skyways traversed by commercial flights. They exist even beyond our immediate experience. Think of the World Wide Web, the power grid and the universe, of which the Milky Way is an infinitesimal node in a seemingly boundless network of galaxies. Few such systems of interacting connections, however, match the complexity of the one underneath our skull. Neuroscience has gained a higher profile in recent years, as many people have grown familiar with splashily colored images that show brain regions “lighting up” during a mental task. There is, for instance, the temporal lobe, the area by your ear, which is involved with memory, and the occipital lobe at the back of your head, which dedicates itself to vision. What has been missing from this account of human brain function is how all these distinct regions interact to give rise to who we are. Our laboratory and others have borrowed a language from a branch of mathematics called graph theory that allows us to parse, probe and predict complex interactions of the brain that bridge the seemingly vast gap between frenzied neural electrical activity and an array of cognitive tasks—sensing, remembering, making decisions, learning a new skill and initiating movement. This new field of network neuroscience builds on and reinforces the idea that certain regions of the brain carry out defined activities. In the most fundamental sense, what the brain is—and thus who we are as conscious beings—is, in fact, defined by a sprawling network of 100 billion neurons with at least 100 trillion connecting points, or synapses. © 2019 Scientific American

Keyword: Consciousness
Link ID: 26379 - Posted: 07.02.2019

Tam Hunt How can you know that any animal, other human beings, or anything that seems conscious, isn’t just faking it? Does it enjoy an internal subjective experience, complete with sensations and emotions like hunger, joy, or sadness? After all, the only consciousness you can know with certainty is your own. Everything else is inference. The nature of consciousness makes it by necessity a wholly private affair. These questions are more than philosophical. As intelligent digital assistants, self-driving cars and other robots start to proliferate, are these AIs actually conscious or just seem like it? Or what about patients in comas – how can doctors know with any certainty what kind of consciousness is or is not present, and prescribe treatment accordingly? In my work, often with with psychologist Jonathan Schooler at the University of California, Santa Barbara, we’re developing a framework for thinking about the many different ways to possibly test for the presence of consciousness. There is a small but growing field looking at how to assess the presence and even quantity of consciousness in various entities. I’ve divided possible tests into three broad categories that I call the measurable correlates of consciousness. There are three types of ways to gauge consciousness. You can look for brain activity that occurs at the same time as reported subjective states. Or you can look for physical actions that seem to be accompanied by subjective states. Finally, you can look for the products of consciousness, like artwork or music, or this article I’ve written, that can be separated from the entity that created them to infer the presence – or not – of consciousness. © 2010–2019, The Conversation US, Inc.

Keyword: Consciousness
Link ID: 26378 - Posted: 07.02.2019

By Nathan Dunne I would stare at my hands and think, “I’m not me.” No matter where I was, in the middle of a busy street or at my dining table at home, the condition would be the same. It was like looking at my hands through a plate of glass. Although I could feel the skin on my palms, it did not feel like my own. Half of myself would move through the day while the other half watched. I was split in two. Nothing I did would relieve the condition. I went to see an ophthalmologist, convinced I had cataracts. The verdict was near-perfect vision. I tried taking time off work, talking with family and writing notes about how my life had become a simulation. Each morning I would stare at the mirror in an attempt to recognize myself, but the distance between my body and this new, outer eye only grew larger. I began to believe I was becoming psychotic and would soon be in a psychiatric ward. I was a 28-year-old, working as a copywriter while pursuing a PhD in art history, and I felt my life was nearing its end. One evening in April 2008, as I contemplated another helpless night trapped beyond my body, full blown panic set in. I took up the phone, ready to dial for emergency, when suddenly music began to play from downstairs. It was a nauseating pop song that my neighbor played incessantly, but something about the melody gave me pause. The next day I began a series of frustrating doctor’s visits. First with my physician, then a neurologist, gastroenterologist and chiropractor. I said that I had never taken drugs or drank alcohol excessively. While I was fatigued from my doctoral study, I didn’t think this qualified me for the split in the self that had occurred. © 1996-2019 The Washington Post

Keyword: Attention
Link ID: 26372 - Posted: 07.01.2019

By Bret Stetka The hippocampus is a small curl of brain, which nests beneath each temple. It plays a crucial role in memory formation, taking our experiences and interactions and setting them in the proverbial stone by creating new connections among neurons. A report published on June 27in Science reveals how the hippocampus learns and hard wires certain experiences into memory. The authors show that following a particular behavior, the hippocampus replays that behavior repeatedly until it is internalized. They also report on how the hippocampus tracks our brain’s decision-making centers to remember our past choices. Previous research has shown that the rodent hippocampus replays or revisits past experiences during sleep or periods of rest. While a rat navigates a maze, for example, so-called place cells are activated and help the animal track its position. Following their journey through the maze, those same cells are reactivated in the exact same pattern. What previously happened is mentally replayed again. The authors of the new study were curious whether this phenomenon only applies to previous encounters with a particular location or if perhaps this hippocampal replay also applies to memory more generally, including mental and nonspatial memories. It turns out it does. In the study, 33 participants were presented with a series of images containing both a face and a house. They had to judge the age of either one or the other. If during the second trial, the age of the selected option remained the same, the judged category also did not change in the subsequent trial. If the ages differed, the judged category flipped to the other option in the next round. © 2019 Scientific American

Keyword: Attention; Learning & Memory
Link ID: 26367 - Posted: 06.28.2019

By Benedict Carey Doctors have known for years that some patients who become unresponsive after a severe brain injury nonetheless retain a “covert consciousness,” a degree of cognitive function that is important to recovery but is not detectable by standard bedside exams. As a result, a profound uncertainty often haunts the wrenching decisions that families must make when an unresponsive loved one needs life support, an uncertainty that also amplifies national debates over how to determine when a patient in this condition can be declared beyond help. Now, scientists report the first large-scale demonstration of an approach that can identify this hidden brain function right after injury, using specialized computer analysis of routine EEG recordings from the skull. The new study, published Wednesday in the New England Journal of Medicine, found that 15 percent of otherwise unresponsive patients in one intensive care unit had covert brain activity in the days after injury. Moreover, these patients were nearly four times more likely to achieve partial independence over the next year with rehabilitation, compared to patients with no activity. The EEG approach will not be widely available for some time, due in part to the technical expertise required, which most I.C.U.’s don’t yet have. And doctors said the test would not likely resolve the kind of high-profile cases that have taken on religious and political dimensions, like that of Terri Schiavo, the Florida woman whose condition touched off an ethical debate in the mid-2000s, or Karen Ann Quinlan, a New Jersey woman whose case stirred similar sentiments in the 1970s. Those debates centered less on recovery than on the definition of life and the right to die; the new analysis presumes some resting level of EEG, and that signal in both women was virtually flat. © 2019 The New York Times Company

Keyword: Consciousness; Brain imaging
Link ID: 26363 - Posted: 06.27.2019