First Out-of-body Experience Induced In Laboratory Setting

Source:

http://www.sciencedaily.com/releases/2007/08/070823141057.htm

Science Daily — A neuroscientist working at UCL (University College London) has devised the first experimental method to induce an out-of-body experience in healthy participants. In a paper published in Science, Dr Henrik Ehrsson, UCL Institute of Neurology, outlines the unique method by which the illusion is created and the implications of its discovery.

An out-of-body experience (OBE) is defined as the experience in which a person who is awake sees his or her own body from a location outside the physical body. OBEs have been reported in clinical conditions where brain function is compromised, such as stroke, epilepsy and drug abuse. They have also been reported in association with traumatic experiences such as car accidents. Around one in ten people claim to have had an OBE at some time in their lives.
Dr Ehrsson said: "Out-of-body experiences have fascinated mankind for millennia. Their existence has raised fundamental questions about the relationship between human consciousness and the body, and has been much discussed in theology, philosophy and psychology. Although out-of-body experiences have been reported in a number of clinical conditions, the neuro-scientific basis of this phenomenon remains unclear.
"The invention of this illusion is important because it reveals the basic mechanism that produces the feeling of being inside the physical body. This represents a significant advance because the experience of one's own body as the centre of awareness is a fundamental aspect of self-consciousness."
Discovering this means of inducing an OBE could also have industrial applications, as Dr Ehrsson explains: "This is essentially a means of projecting yourself, a form of teleportation. If we can project people into a virtual character, so they feel and respond as if they were really in a virtual version of themselves, just imagine the implications. The experience of playing video games could reach a whole new level, but it could go much beyond that. For example, a surgeon could perform remote surgery, by controlling their virtual self from a different location."
The set-up of the illusion is as follows: the study participant sits in a chair wearing a pair of head-mounted video displays. These have two small screens over each eye, which show a live film recorded by two video cameras placed beside each other two metres behind the participant's head. The image from the left video camera is presented on the left-eye display and the image from the right camera on the right-eye display. The participant sees these as one 'stereoscopic' (3D) image, so they see their own back displayed from the perspective of someone sitting behind them.
The researcher then stands just beside the participant (in their view) and uses two plastic rods to simultaneously touch the participant's actual chest out-of-view and the chest of the illusory body, moving this second rod towards where the illusory chest would be located, just below the camera's view.
The participants confirmed that they had experienced sitting behind their physical body and looking at it from that location. Dr Ehrsson said: "This was a bizarre, fascinating experience for the participants -- it felt absolutely real for them and was not scary. Many of them giggled and said 'Wow, this is so weird!'".
To test the illusion further and provide objective evidence, Dr Ehrsson then performed an additional experiment to measure the participants' physiological response -- specifically the level of perspiration on the skin -- in a scenario where they felt the illusory body was threatened. Their bodily response strongly indicated that they thought the threat was real.
The creation of this perceptual illusion stems from an idea Dr Ehrsson had as a medical student, when he wondered what would happen to the 'self' if you could effectively move your eyes to another part of the room, just a few metres away, so you could observe yourself from an outside perspective. Would the self 'follow' the eyes or stay in the body"
Dr Ehrsson added: "The illusion is different from anything published previously. It is the first to involve a change in the perceived location of the self, relative to the physical body. It is also different from any virtual reality set-up because it examines what happens when you look at yourself, and there is also multisensory information that triggers the illusion. There has been no way of inducing an OBE in healthy people before, apart from unsubstantiated reports in occult literature. It's a very exciting development, and has implications for a range of disciplines from neuroscience to theology."
Article: 'The experimental induction of out-of-body experiences' is published in the advance online edition of Science on Thursday 23rd August.
Note: This story has been adapted from a news release issued by University College London.

Fausto Intilla

www.oloscience.com

Brains Learn Better At Night

Source:

http://www.sciencedaily.com/releases/2007/08/070817213343.htm

Science Daily — If you think that the idea of a morning person or an evening person is nonsense, then postgraduate student Martin Sale and his colleagues from the University of Adelaide have news for you.

They have found that the time of day influences your brain’s ability to learn—and the human brain learns more effectively in the evening.
And by identifying at what point in the day the brain is best able to operate, rehabilitation therapy can be targeted to that time, when recovery is maximised.
“Our research has several future applications,” Mr Sale says. “If the brains of stroke patients can be artificially stimulated to improve learning, they may be able to recover better and faster.”
The researchers used a magnetic coil over the head to stimulate nerve activity in the brain, and linked it to an electrical stimulus of the hand.
Mr Sale, from the School of Molecular and Biomedical Science at the University of Adelaide, discovered that the brain’s capacity to control hand movements is influenced by the time of day.
His study found that larger changes are induced when the experiments are performed in the evening, as compared with mornings.
“Such time-of-day variations in function are not unusual. Organisms are adapted to the continual change in light and dark during a 24 hour period to avoid predators and to reproduce faster,” he says.
“For example, the petals of many flowers only open during the day, while some organisms only reproduce at night. In humans, these rhythms are governed by a variety of hormones that control many bodily functions.”
Martin Sale is one of 16 young scientists presenting their research to the public for the first time thanks to Fresh Science, a national program sponsored by the Federal and Victorian Governments which identifies new and interesting research being done by early-career scientists around the country.
Note: This story has been adapted from a news release issued by University of Adelaide.

Fausto Intilla

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The Brain Doesn't Like Visual Gaps And Fills Them In

Source:

http://www.sciencedaily.com/releases/2007/08/070820135833.htm

Science Daily — When in doubt about what we see, our brains fill in the gaps for us by first drawing the borders and then ‘coloring’ in the surface area, new research has found. The research is the first to pinpoint the areas in the brain, and the timing of their activity, responsible for how we see borders and surfaces.

“When you look at objects, they can be defined as either the contour of the object or surface features, like color and brightness. There’s been a debate in neuroscience about how this occurs—do you first see the contour and then fill it in like a coloring book, or do you see the surface and from there grow it out to build the contour?,” Anna Roe, Vanderbilt University associate professor of psychology and one of the study’s authors, said. “Our examination of individual neurons in the visual cortex revealed that the former is true—our brains process the border information first and fill in the surface information second, causing us to perceive something that is in fact not really there.”
The authors open the paper with the example of vases from China’s Song dynasty that use very faint contrast borders to create the illusion of shading on a one-color background. The phenomenon is known as edge induction, and is believed to help us distinguish objects in dim light or through fog, or when we see objects through dappled light, such as would be found in a forest. In these conditions, the authors hypothesized that our brain seizes upon the edge and then fills in the rest of the object. In the case of the vase, we see the contrasting border and perceive that the areas within the border also are of that contrasting color, even though in fact they are the same color as the rest of the background.
The authors set out to understand what is happening at the neural level in these situations by examining activity in individual neurons in the visual cortex of cats while the cats were looking at an illusion much like the one presented by the vase. The illusion, called the Craik-O’Brien-Cornsweet illusion, is a rectangular field of gray divided in half by a shaded middle border. The area to the left of the border appears brighter than that to the right. In reality, the brighter and darker areas exist only at the border—the surrounding areas to the left and the right are the exact same brightness. The illusion causes the brain to apply the brightness and darkness it sees at the border to the areas to the left and the right.
“The Cornsweet illusion is a very good example of edge induction—taking information from the edge of an object and applying it to the rest of the object,” Roe said. “It demonstrates that a lot of what you perceive is actually a construction in your brain of border information plus surface information—in other words, a lot of what you see is not accurate. We were interested in understanding how the border and surface information combine to achieve what you end up seeing.”
Roe and her colleagues found that when presented with the illusion, the neurons that respond to edges fired first and the neurons that respond to texture responded second. This firing delay was only seen when the subjects perceived a brightness difference—when presented with an image that did not appear different in brightness, the neurons fired at the same time.
“We found that the timing of neuronal firings is not a fixed thing in the brain, it depends on what you are looking at,” Roe said. “This is a great example of neuronal activity being dependent on a stimulus that is directly correlated to how we perceive objects. It is not hardwired—neural activity and relationships between neurons change depending upon the stimulus.”
The authors also discovered that the neuronal response to the illusion took place by neurons residing in two separate areas of the visual cortex.
“It seems like this kind of border to surface delay was really prevalent in cell pairs in the two different areas of the visual cortex,” Roe said. “This is the first example of interaction between two areas underlying border-surface perception. It emphasizes in a way that hasn’t been emphasized before how important inter-area relations are in visual perception.
An important implication of this study is that it emphasizes the key role of neuronal interactions in the brain, rather than simply neuronal activity level, in visual perception,” Roe said. “Thus, methods that are good at detecting activity levels, such as fMRI, may miss some of these basic mechanisms. So, it’s important to have different tools to assess different aspects of brain response.”
Roe’s co-authors were Chou P. Hung, National Yang Ming University, Taipei, Taiwan and Benjamin M. Ramsden, West Virginia University School of Medicine.
Roe is an investigator in the Vanderbilt Kennedy Center for Research on Human Development, a member of the Vanderbilt Center for Integrative and Cognitive Neuroscience and a member of the Vanderbilt Vision Research Center. The National Institutes of Health, the Whitehall Foundation, Packard Foundation, Yale Brown-Coxe Postdoctoral Fellowship, Taiwan Ministry of Education, and the Taiwan National Science Council funded the research.
To view more examples of the illusions mentioned in this story visit Exploration, Vanderbilt University’s online research magazine, at http://www.vanderbilt.edu/exploration/stories/edgeinduction.html.
The research was published online by Nature Neuroscience on Aug. 19.

Fausto Intilla

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Process For Storing And Erasing Long-term Memories Discovered

Source:

http://www.sciencedaily.com/releases/2007/08/070816143807.htm

Science Daily — What happens in our brains when we learn and remember? Are memories recorded in a stable physical change, like writing an inscription permanently on a clay tablet?

Prof. Yadin Dudai, Head of the Weizmann Institute's Neurobiology Department, and his colleagues are challenging that view. They recently discovered that the process of storing long-term memories is much more dynamic, involving a miniature molecular machine that must run constantly to keep memories going. They also found that jamming the machine briefly can erase long-term memories. Their findings, which appeared August 16 in the journal Science, may pave the way to future treatments for memory problems.
Dudai and research student Reut Shema, together with Todd Sacktor of the SUNY Downstate Medical Center, trained rats to avoid certain tastes. They then injected a drug to block a specific protein into the taste cortex -- an area of the brain associated with taste memory. They hypothesized, on the basis of earlier research by Sacktor, that this protein, an enzyme called PKMzeta, acts as a miniature memory "machine" that keeps memory up and running. An enzyme causes structural and functional changes in other proteins: PKMzeta, located in the synapses -- the functional contact points between nerve cells -- changes some facets of the structure of synaptic contacts.
It must be persistently active, however, to maintain this change, which is brought about by learning. Silencing PKMzeta, reasoned the scientists, should reverse the change in the synapse. And this is exactly what happened: Regardless of the taste the rats were trained to avoid, they forget their learned aversion after a single application of the drug.
The technique worked as successfully a month after the memories were formed (in terms of life span, more or less analogous to years in humans) and all signs so far indicate that the affected unpleasant memories of the taste had indeed disappeared. This is the first time that memories in the brain were shown to be capable of erasure so long after their formation.
"This drug is a molecular version of jamming the operation of the machine," says Dudai. "When the machine stops, the memories stop as well." In other words, long-term memory is not a one-time inscription on the nerve network, but an ongoing process which the brain must continuously fuel and maintain. These findings raise the possibility of developing future, drug-based approaches for boosting and stabilizing memory.
Prof. Yadin Dudai's research is supported by the Norman and Helen Asher Center for Brain Imaging; the Nella and Leon Benoziyo Center for Neurosciences; the Carl and Micaela Einhorn-Dominic Brain Research Institute; the Irwin Green Alzheimer's Research Fund; and the Sylvia and Martin Snow Charitable Foundation. Prof. Dudai is the incumbent of the Sara and Michael Sela Professorial Chair of Neurobiology.
Note: This story has been adapted from a news release issued by Weizmann Institute of Science.

Fausto Intilla

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Cognitive Revolution: Integrating Computing, Nanotech, Simulation And You

Source:

http://www.sciencedaily.com/releases/2007/08/070811213026.htm

Science Daily — Imagine a world where a machine creates a “virtual you” by modeling how you think and your expertise on a subject. Or one where your car’s computer appreciates your driving skills and compensates for your limitations.

That’s the world Sandia National Laboratories has entered full throttle through its Cognitive Science and Technology Program (CS&T).
A revolution is at hand, says Chris Forsythe, member of the Labs’ cognition research team. It’s not one of just better guns and weapons for national security. Instead, “it’s a revolution of the mind — of how people think and how machines can help people work better.”
Focus on individual
A large portion of Sandia’s program today focuses on the uniqueness of the individual interacting with others and with machines. It involves using machines to help humans perform more efficiently and embedding cognitive models in machines so they interact with users more like people interact with one another. The result is the ability for researchers to take advantage of the basic strengths of humans and machines while mitigating the weaknesses of each.
Cognitive projects and research at Sandia span a whole gamut of areas, ranging from student training to assisting with Yucca Mountain licensing, from designing “smart” cars to using video-like games to train military personnel, and from determining how neurons give rise to memory to global terrorist threat detection.
The initial decision for Sandia to develop cognitive technologies is based on the belief that “there are numerous positive impacts cognitive systems technologies can have on our national security,” says Russ Skocypec, senior manager of Sandia’s Human, Systems, and Simulation Technologies Department.
Today’s conflicts, he says, are unlike others over the past century. Although all wars are driven by humans, major influences on the outcomes have differed. World War I was a chemists’ war, World War II a physicists’ war, and the Cold War an economic war. Today, he believes, “we are engaged in a human war that is influenced primarily by individual human beings rather than technology or bureaucracy.”
That is why he considers it appropriate for Sandia, a laboratory with national security as its mission, to use its resources to better understand the minds of this country’s adversaries, as well as to use machines to enhance the Labs’ abilities to recognize patterns, deal with massive amounts of data, solve perplexing problems, and perform complex activities.
While Sandia dipped its toes in cognitive research in the late 1990s, the Labs’ real effort in the area started in 2002 when the program won an internally funded LDRD grand challenge. Based in part on the success and path set by the grand challenge in 2005, the former Mission Council — a group that consisted of senior Sandia vice presidents — selected cognitive science and technology (CS&T) as a research focus area for the Labs.
Strategic planning for cognitive science and technology
During the spring and summer of 2006, the cognition team conducted two investigations. The first looked at what cognitive capabilities exist at Sandia.
The second examined opportunities involving the convergence of Sandia’s initiatives in the areas of cognition, biotechnologies, and nanotechnologies. This led to a Cognitive Science and Technology Plan with three technical objectives — a basic science understanding of the human brain, mind, and behavior; improved human performance; and advanced human-machine systems at all scales.
“The plan is at the level of ‘send a man to the moon’ — beyond the scope of what any one institution can possibly do,” Forsythe says. “It’s a synthesis of ideas. Now, our intent is to home in on a few areas in which the labs can make a unique and profound contribution.”
Forsythe says there are two elements to Sandia’s strategic planning for cognition.
“What makes most sense is for Sandia to select areas where we have unique, collective technical strengths, areas that few others in the world can do as well,” Forsythe says. “These include such capabilities as high performance computing, nanotech, physics-based modeling and simulation, and surety.” That is the first element. (Surety is an engineering discipline that emphasizes methods and technologies enabling assessment and technical solutions for the combined safety, security, and reliability of systems.)
The second involves a focus on opportunities where specific national security problems have a human factor.
John Wagner, manager of Sandia’s Cognitive and Exploratory Systems and Simulations Department, says the new area of research means “profound opportunities exist for the Labs.”
“CS&T’s ambitious direction may not be realized for many decades, but the information required for progress is emerging today,” he says. “It is reasonable to expect future discoveries will become the Nobel-class achievements for the cognitive and neuroscience communities at large in the years to come.”
What is a cognitive system?
The term “cognitive systems” has been used worldwide to identify a variety of programs, initiatives, and technologies. However, so many varied uses have led to ambiguity of meaning. Sandia has established its own definition of cognitive systems: “Cognitive systems consist of technologies that utilize as an essential component one or more computational models of human cognitive processes or the knowledge of specific experts, users, or other individuals.”
Wagner says that cognitive research at Sandia — like most worldwide — is in its infancy. He anticipates that within the next decade research that seems like science fiction today will be a daily part of everyone’s lives. The cognitive revolution will be in full bloom.
“Once that happens, the best of both worlds can happen,” Wagner says. “If we understand human cognition better, we can work together as a nation to reduce tension, find problems before they turn into armed conflict, and to work toward actions that establish and maintain peace worldwide.”
Funding for the research has come from the Office of Naval Research, Sandia’s internal Laboratory Directed Research and Development (LDRD) program, Department of Energy, the Defense Advanced Research Projects Agency (DARPA), and other government agencies. The CS&T program also benefits from collaborations with the University of New Mexico, the MIND Imaging Center in Albuquerque, and most recently the University of Illinois at Urbana-Champaign.
Sandia is a National Nuclear Security Administration (NNSA) laboratory. It is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin company, for the U.S. Department of Energy’s National Nuclear Security Administration.
Note: This story has been adapted from a news release issued by Sandia National Laboratories.

Fausto Intilla

www.oloscience.com

Toddlers Are Capable Of Introspection

Source:

http://www.sciencedaily.com/releases/2007/08/070815135023.htm

Science Daily — Preschoolers are more introspective than we give them credit for, according to new research by Simona Ghetti, assistant professor of psychology at UC Davis.Ghetti and her co-investigator, Kristen Lyons, a graduate student in psychology at UC Davis, will present their findings August 17, at the annual meeting of the American Psychological Association in San Francisco.Scientists have demonstrated that dolphins, monkeys and even rats can engage in some form of "metacognition," or an awareness of their own thought processes.

But developmental psychologists have assumed that human children do not develop this capability before about age 5.Lyons and Ghetti have toppled that assumption by teaching 3- and 4-year-olds to communicate their awareness of their thought processes using pictures rather than words."We've shown that even very young children can think about their thinking," Ghetti said. "The reason we haven't appreciated it before now is that the studies that have been used to test for it have been too verbally demanding."The UC Davis researchers devised a novel method to investigate metacognition in early childhood. They taught their preschool subjects to point to a photo of a confident-looking face when they felt confident they had the right answer to a question, and to a photo of a doubtful-looking child when they were not confident they had the right answer.The tests showed that young children are aware of their uncertainty in the moment. Even 3-year-olds pointed to the confident face when they correctly identified, for example, a drawing of a monkey that had some features removed to make it harder to recognize. They pointed to the doubtful face if they could not come up with a correct answer."Even 3-year-olds are more confident when they're right than when they're wrong," Ghetti said.How children develop the ability to experience, recognize and understand their thoughts and emotions is a topic of increasing scientific interest, since self-awareness is a prerequisite for the development of a wide range of important human traits, from a conscience to healthy relationships.

Note: This story has been adapted from a news release issued by University of California - Davis.

Fausto Intilla

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Hand Gestures Dramatically Improve Learning

Source:

http://www.sciencedaily.com/releases/2007/07/070725105957.htm

Science Daily — Kids asked to physically gesture at math problems are nearly three times more likely than non-gesturers to remember what they've learned. In today's issue of the journal Cognition, a University of Rochester scientist suggests it's possible to help children learn difficult concepts by providing gestures as an additional and potent avenue for taking in information. "We've known for a while that we use gestures to add information to a conversation even when we're not entirely clear how that information relates to what we're saying," says Susan Wagner Cook, lead author and postdoctoral fellow at the University.

"We asked if the reverse could be true; if actively employing gestures when learning helps retain new information." It turned out to have a more dramatic effect than Cook expected. In her study, 90 percent of students who had learned algebraic concepts using gestures remembered them three weeks later. Only 33 percent of speech-only students who had learned the concept during instruction later retained the lesson. And perhaps most astonishing of all, 90 percent of students who had learned by gesture alone--no speech at all--recalled what they'd been taught. Cook used a variation on a classic gesturing experiment. When third graders approach a two-sided algebra equation, such as "9+3+6=__+6" on a blackboard, they will likely try to solve it in the simple way they have always approached math problems. They tend to think in terms of "the equal sign means put the answer here," rather than thinking that the equal sign divides the problem into two halves. As a result, children often completely ignore the final "+6." However, even when children discard that final integer, they will often point to it momentarily as they explain how they attacked the problem. Those children who gestured to the number, even though they may seem to ignore it, are demonstrating that they have a piece of information they can't reconcile. Previous work has shown that the children with that extra bit of disconnected knowledge are the ones ready to learn, which suggests that perhaps giving children extra information in their gesture could lead to their learning. Cook divided 84 third and fourth graders into three groups. One group expressed the concept verbally without being allowed to use gestures. The second group was allowed to use only gestures and no speech, and the third group employed both. Teachers gave all the children the same instruction, which used both speech and gesture. After three weeks, the children were given regular in-school math tests. Of those children who had learned to solve the problem correctly, only a third of the speech-only students remembered the principles involved, but that figure rose dramatically for the speech-and-gesture, and the gesture-only group, to 90-percent retention. "My intuition is that gestures enhance learning because they capitalize on our experience acting in the world," says Cook. "We have a lot of experience learning through interacting with our environment as we grow, and my guess is that gesturing taps into that need to experience." Cook plans to look into how gesturing could be implemented effectively in classrooms to make a noticeable improvement in children's learning. "Gesturing does have one clear benefit," Cook adds. "It's free."

Note: This story has been adapted from a news release issued by University of Rochester.

Fausto Intilla

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Emotional Memories Can Be Suppressed With Practice

Source:

http://www.sciencedaily.com/releases/2007/07/070712143304.htm

Science Daily — A new University of Colorado at Boulder study shows people have the ability to suppress emotional memories with practice, which has implications for those suffering from conditions ranging from post-traumatic stress disorder to depression. The study, which measured brain activity in test subjects who were trained to suppress memories of negative images, indicated two mechanisms in the prefrontal region of the brain were at work, said CU-Boulder doctoral candidate Brendan Depue, lead study author.

The study may help clinicians develop new therapies for those unable to suppress emotionally distressing memories associated with disorders like post-traumatic stress disorder, phobias, depression, anxiety and obsessive-compulsive syndrome, he said. The study was published in the July 13 issue of Science. Co-authors on the study included CU-Boulder Associate Professor Tim Curran and Professor Marie Banich of the psychology department. All three authors are affiliated with CU-Boulder's Center for Neuroscience and the Institute of Cognitive Sciences, and Banich also is affiliated with the CU-Denver and Health Sciences Center. "We have shown in this study that individuals have the ability to suppress specific memories at a particular moment in time through repeated practice," Depue said. "We think we now have a grasp of the neural mechanisms at work, and hope the new findings and future research will lead to new therapeutic and pharmacological approaches to treating a variety of emotional disorders." During the training phase of the study, subjects were asked to learn 40 different pairs of pictures, each pair consisting of a "neutral" human face and a disturbing picture such as a car crash, a wounded soldier, a violent crime scene or an electric chair, Depue said. After memorizing each associated pair, the subjects were fitted with special viewing goggles and placed in MRI scanners at CU's Health Sciences Center in Denver. Subjects were shown only the face images and asked to either think about, or not think about, the disturbing image previously associated with each face, he said. The functional brain imaging scans taken during the study indicated the coordination for memory suppression occurred in the brain's prefrontal cortex, considered by neuroscientists to be the "seat of cognitive control," he said. The team found that two specific regions of the prefrontal cortex appear to work in tandem to suppress particular posterior brain regions like the visual cortex, the hippocampus and amygdala, which are involved in tasks like visual recall, memory encoding and retrieval, and emotional output, he said. "These results indicate memory suppression does occur, and, at least in nonpsychiatric populations, is under the control of prefrontal regions," the researchers wrote in Science. The most anterior portion of the prefrontal cortex highlighted in the study is a relatively recent feature in brain evolution and is greatly enlarged in humans when compared to great apes, said Depue. The study showed the subjects were able to "exert some control over their emotional memories," said Depue. "By essentially shutting down specific portions of the brain, they were able to stop the retrieval process of particular memories." Depue speculated that memory suppression could be a positive evolutionary trait, using the example of a Stone Age hunter narrowly escaping from a lion while hunting antelope. "If the hunter became so beleaguered by memories of that incident that he stopped hunting, then he would have starved to death." It is not clear to what extent an extremely traumatic emotional memory, like a violent battlefield incident or a crippling car accident, manifests itself in the human brain, said Depue. "In cases like this, a person could need thousands of repetitions of training to suppress such memories. We just don't know yet." Originated by psychologist Sigmund Freud more than a century ago, the concept of repressed memories is extremely controversial, said Depue. There is considerable debate today over whether repressed memories and suppressed memories are interchangeable terms, and even as to whether repressed memories exist at all, he said. "The debate over repressed memories probably won't be resolved in my lifetime," said Depue. "I think the important thing here is that we have identified neural mechanisms with potential for helping the clinical community develop new therapeutic and pharmaceutical approaches for people suffering from emotional disorders." The study was funded with support from CU-Boulder's Graduate School, vice chancellor for research and the university's Institute for Cognitive Sciences.

Note: This story has been adapted from a news release issued by University of Colorado at Boulder.

Fausto Intilla

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Infants Have 'Mind-reading' Capability, Study Shows

Source:

http://www.sciencedaily.com/releases/2007/08/070803110811.htm

Science Daily — One of the unique characteristics of humans that distinguish us from the animal kingdom is the ability to represent others' beliefs in our own minds. This sort of intuitive mind-reading, according to experts, lays the cognitive foundations of interpersonal understanding and communication.Despite its importance, scientists have yet to reach a consensus on how this psychological function develops.

Some argue that this complex and flexible ability is acquired at the age of 3-4 years and only after prerequisites such as language grammar are fulfilled. Others suggest specialized developmental mechanisms are in place at birth, allowing infants to refine this ability very early in life.Luca Surian, a psychologist at the University of Trento in Italy, and his colleagues believe they have made some progress in the debate. In a study published in the July issue of Psychological Science, a journal of the Association for Psychological Science, Surian found that 13-month-old infants were able to exhibit the ability to attribute mental content.In two experiments, the researchers had the infants watch a series of animations in which a caterpillar went in search of food (either a red apple or a piece of cheese) that was hidden behind a screen. In some scenes, the caterpillar could see a human hand situating the food, but in others there was no hand to drop a hint. The caterpillar was either successful finding the preferred food behind the correct screen, or went behind an alternative screen with the other type of food behind it. When the caterpillars didn't do what one would expect -- going to one screen despite seeing the human hand place the desired food behind the other -- infants tended to look at the animation longer, suggesting puzzlement about the caterpillar's actions. "This result," says Surian, "Suggests the infants expected searches to be effective only when the [caterpillar] had had access to the relevant information."The findings indicate that the mental structures and the psychological reasoning skills allowing us predict other's behavior are in place at a very young age and their development does not entirely rely upon the environment or associative learning mechanisms. Surian proposes that "infants who expect agents' behavior to be guided by such internally available information thereby exhibit an ability to attribute mental content -- and this is mind reading proper, however rudimentary."

Note: This story has been adapted from a news release issued by Association for Psychological Science.

Fausto Intilla

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Scientists Unveil The 'Face' Of A New Memory

Source:

http://www.sciencedaily.com/releases/2007/07/070725093713.htm

Science Daily — A century-old dream of neuroscientists to visualize a memory has been fulfilled, as University of California, Irvine researchers, using newly developing microscopic techniques, have captured first-time images of the changes in brain cell connections following a common form of learning.Detailed in the Journal of Neuroscience, the study shows that synaptic connections in a region of rats’ brains critical to learning change shape when the rodents learn to navigate a new, complex environment.

In turn, when drugs are administered that block these changes, the rats don’t learn, confirming the essential role the shape change plays in the production of stable memory. “This is the first time anyone has seen the physical substrate, the ‘face,’ of newly encoded memory. We have cleared a hurdle that once seemed insurmountable,” said Gary Lynch, professor of psychiatry and human behavior at UC Irvine and leader of one of the two research teams involved in the studies.The new behavioral experiments followed a series of recent discoveries by the UC Irvine group concerning the synaptic changes responsible for long-term potentiation (LTP), a physiological effect closely related to memory storage. Those studies used brain slices from rats, maintained alive in experimental chambers, to identify chemical markers for synapses that had recently experienced the LTP effect. The new study used live animals.Working with advanced microscopic techniques called restorative deconvolution microscopy, the UC Irvine team found that the LTP-related markers appear during learning and are associated with expanded synapses in the hippocampus. Because the size of a synapse relates to its effectiveness in transmitting messages between neurons, the new results indicate that learning improves communication between particular groups of brain cells.The findings open the way for one of the great objectives of the life sciences: mapping the distribution of memory across brain regions. The quest for the location of memory traces, or “engrams” as they are often called, preoccupied researchers for much of the 20th century but failed because there was no way to tag synapses modified by recent learning. The new results from the UC Irvine studies remove this obstacle.UC Irvine researchers will shortly set up a consortium of laboratories directed at producing the first maps of memory.Vadim Fedulov, Christopher S. Rex, Danielle A. Simmons and Christine M. Gall of UC Irvine, and Linda Palmer of Carnegie Mellon University, also worked on this study, which received support from the National Institutes of Health.

Note: This story has been adapted from a news release issued by University of California - Irvine.

Fausto Intilla

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