By Timothy Brady and Adena Schachner Perception is mathematically impossible. This might seem like a bold statement—after all, you are perceiving these letters right now—but it’s nonetheless true. Imagine a black-and-white line drawing of a cube on a sheet of paper. Although this drawing looks to us like a picture of a cube, there are actually an infinity of other three-dimensional figures that could have produced the same set of lines when collapsed on the page. But we don't notice any of these alternatives. Happily for all of us, our visual systems have more to go on than just bare perceptual input. They use heuristics and short cuts, based on the physics and statistics of the natural world, to make the “best guesses” about the nature of reality. Just as we interpret a two-dimensional drawing as representing a three-dimensional object, we interpret the two-dimensional visual input of a real scene as indicating a three-dimensional world. Our perceptual system makes this inference automatically, using educated guesses to fill in the gaps and make perception possible. It turns out that our brains use the same intelligent guessing process to reconstruct the past, in addition to using it help perceive the world. Memory itself is not like a video-recording, with a moment-by-moment sensory image. In fact, it’s more like a puzzle: we piece together our memories, based on both what we actually remember and what seems most likely given our knowledge of the world. Just as we make educated guesses in perception, our minds’ best educated guesses help “fill in the gaps” of memory, reconstructing the most plausible picture of what happened in our past.

Keyword: Vision
Link ID: 12352 - Posted: 06.24.2010

By Neil H. Shubin I started teaching human anatomy at the same time my university renovated my laboratory. As it turns out, this coincidence could not have been more propitious. Teaching anatomy for the first time can be a struggle, and it is not just because there are an enormous number of names to learn. A glimpse inside the body reveals structures left inside of us during the course of evolution, which often seem a confused jumble, with arteries, nerves and other structures taking odd paths to get from one part of the body to another. While I was struggling to understand the body’s internal structures, I was given space in a 100-year-old building that needed to be renovated into a modern laboratory. When we opened the walls to look at the plumbing, wiring and other mechanicals, we saw a tangle that made no apparent sense; cables, wires and pipes took bizarre loops and turns throughout the building. Nobody in their right mind would have designed my building to conform to the snarled mess we saw when the wall was removed. Constructed in 1896, the utilities reflect an old design that has been jury-rigged for each renovation done over previous decades. If you want to understand the twisting pathways for a cable or a pipe, you have to understand their history and how they have been modified over the years. The same is true for structures in the human body. © 1996-2008 Scientific American Inc.

Keyword: Evolution
Link ID: 12351 - Posted: 06.24.2010

by Ewen Callaway Parasites getting you down? Then take Prozac - if you're a fish, that is. A behaviour-altering parasitic worm has been found to stymie its host's production of serotonin - the same brain chemical that Prozac and other mood-lifting drugs ramp up. While there are no plans to medicate infected fish in the wild, researchers hope to use psychiatric drugs to figure out how trematode worms alter the behaviour of California killifish, which live in coastal estuaries. "There are whole populations where almost 100% of the fish are infected," says Jenny Shaw, a parasitologist at the University of California in Santa Barbara, who led the study. Otherwise healthy infected killifish surface frequently, flashing their silver bellies. When infected, they are 30 times more likely to get eaten by birds than uninfected fish," she says. The parasite's effect on the fish's behaviour is no accident. When the birds defecate, they pass the worm's eggs on to water snails, which in turn spread the worm larvae back to the killifish, thus completing the peculiar lifecycle of Euhaplorchis californiensis. © Copyright Reed Business Information Ltd.

Keyword: Miscellaneous
Link ID: 12350 - Posted: 06.24.2010

Charles Burress, Chronicle Staff Writer Could Sudoku be a balm for anxious people? A new study suggests that intellectually demanding challenges like crossword puzzles or chess may be more successful at keeping worry-prone people from worrying than supposedly relaxing pastimes like watching TV or shopping. Contrary to theories that "as things get harder, anxious people fall apart, this suggests it's the opposite way around," said UC Berkeley psychologist Sonia Bishop, lead researcher on the study published online this week by Nature Neuroscience. The study showed that anxious people performed just as well as others when facing tasks that demanded concentration, but they took more time than others to complete tasks that were easier, Bishop said. Their slower response time to challenges not requiring full attention was accompanied by reduced blood flow to the prefrontal cortex, which serves as the brain's CEO in thinking, planning and active memory. The study indicated that anxious individuals have a weakened ability to block out distractions and that they might benefit from mindfulness training, which often uses meditation and stress-reduction exercises to help increase one's awareness and focus. "With some very popular therapies like mindfulness training, people aren't sure why they work," Bishop said. "This perhaps gives us a rationale for why they do." © 2008 Hearst Communications Inc.

Keyword: Attention; Stress
Link ID: 12349 - Posted: 06.24.2010

By ANAHAD O’CONNOR A recent column pointed out that some Americans, mostly those raised in the age before color television, dream only in black and white. But that observation raised another question — whether people who don’t see images during the day might see them when they shut their eyes at night. For people with normal vision, dreaming is intensely visual. The dream state typically involves vivid scenes and imagery, much of it drawing upon our daytime experiences and concerns (whether conscious or not). Auditory stimulation plays a small role, and the other senses, like taste and smell, are virtually absent. But studies led by a psychologist at the University of Hartford show that for the blind, depending on when in life they lost their sense of sight, the reverse seems to be true. People born without the ability to see report no visual imagery in their dreams, but they do experience a heightening of taste, touch and smell. They also report a higher percentage of dreams that involve mishaps related to traveling or transportation, perhaps reflecting one of their biggest daytime concerns: safely finding their way around. Although individual experiences vary, researchers say people who go blind before age 5 rarely experience visual imagery in their dreams. But those who lose their vision after age 5 often continue to see in their dreams, though the frequency and clarity diminish over time. Copyright 2008 The New York Times Company

Keyword: Sleep
Link ID: 12348 - Posted: 06.24.2010

By NICHOLAS BAKALAR People who are depressed are literally sick at heart: they have a significantly increased risk for cardiovascular disease, and no one knows exactly why. Now three new studies have tried to explain this, and they arrive at subtly different conclusions. The first, led by Dr. Mary A. Whooley of the Veterans Affairs Medical Center in San Francisco, studied 1,017 patients with coronary artery disease for an average of more than four years. Although the study found an association of depression with heart disease, when researchers statistically corrected for other medical conditions, disease severity and physical inactivity, the association disappeared. They concluded with a relatively straightforward explanation: depression leads to physical inactivity, and lack of exercise increases the risk for heart disease. The study appears in the Nov. 26 issue of The Journal of the American Medical Association. A second study, published Tuesday in The Journal of the American College of Cardiology, provides a different perspective. It included more than 6,500 healthy men and women with an average age of 51. Researchers tested them for depressive symptoms and followed them for an average of more than seven years. Copyright 2008 The New York Times Company

Keyword: Depression
Link ID: 12347 - Posted: 12.16.2008

Interview by DEBORAH SOLOMON Your forthcoming book, “How We Decide,” is the latest entry in a growing field that might be called the science of decision-making. How do you explain the fascination with decisions? For the first time, neuroscience can be applied to everyday life. The research on the neurotransmitter dopamine, for instance, can teach us why we play slot machines and overuse our credit cards. Are you a decisive person? No, I’m pathologically indecisive. I wrote the book because I would spend 10 minutes in the cereal aisle choosing between Honey Nut Cheerios and Apple Cinnamon Cheerios. Maybe indecisiveness is the price of being an intelligent human being who understands that actions have consequences. That would be a little too self-congratulatory for me. Indecisiveness means you’re not listening carefully enough to your emotions, which know what you really want and could be whispering, “Go for the Honey Nut Cheerios.” How is that idea any different from the gut decision-making that Malcolm Gladwelldescribes in “Blink”? Fast-blink decisions are not always useful. The brain is full of different tools, and you don’t want to use a hammer if the problem requires more than a blunt hit. Right now, as a consumer society in meltdown mode, aren’t we suffering from a surfeit of fast, unreflective decisions, i.e. spending? I think retail stores and mortgage brokers have become a little too adept at tickling our dopamine neurons, and credit cards don’t help. Copyright 2008 The New York Times Company

Keyword: Attention
Link ID: 12346 - Posted: 06.24.2010

Jennifer Viegas -- If your head is overheated, there's a good chance you'll yawn soon, according to a new study that found the primary purpose of yawning is to control brain temperature. The finding solves several mysteries about yawning, such as why it's most commonly done just before and after sleeping, why certain diseases lead to excessive yawning, and why breathing through the nose and cooling off the forehead often stop yawning. The key yawn instigator appears to be brain temperature. "Brains are like computers," Andrew Gallup, a researcher in the Department of Biology at Binghamton University who led the study, told Discovery News. "They operate most efficiently when cool, and physical adaptations have evolved to allow maximum cooling of the brain." He and colleagues Michael Miller and Anne Clark analyzed yawning in parakeets as representative vertebrates because the birds have relatively large brains, live wild in Australia, which is subject to frequent temperature swings, and, most importantly, do not engage in contagious yawning, as humans and some other animals do. © 2008 Discovery Communications, LLC.

Keyword: Emotions; Sleep
Link ID: 12345 - Posted: 06.24.2010

By Devin Powell When you hear that raspy, female voice coming down the hall, you know that your chain-smoking boss Susan is about to show up in your office. This ability to match a voice with a concrete identity is a complex mental task, thought to be the domain of only a few animals, including humans. But new research in horses suggests that they too evolved the skill. Most creatures have ways to recognize members of their own species. Hamsters sniff, birds listen for a song, and wasps look at facial markings. But researchers have struggled to nail down whether the animals are simply recognizing something familiar or whether they are connecting the stimulus to a specific individual. Behavioral biologists Leanne Proops, Karen McComb, and colleagues at the University of Sussex in the U.K. adapted a technique normally used to study human infants, who cannot verbalize their thoughts. In a common experiment, babies who stare longer at certain objects are assumed to be perplexed by them. Applying this idea to domestic horses, the researchers made a horse watch as a member of its herd was paraded in front of it and subsequently hidden behind a barrier. Proops then played a prerecorded horse whinny over a loudspeaker and watched the observing horse's response. When the call came from a different horse from the herd than the hidden one, the viewing horse seemed confused, looking up at the barrier faster and for 20% longer than when the whinny belonged to the paraded horse, the team reports online this week in the Proceedings of the National Academy of Sciences. The horses are not just reacting to the sound of the whinny, says Proops, who notes that the viewing horse could identify six different horses from its herd: "They understand that every voice is paired to a face." © 2008 American Association for the Advancement of Science.

Keyword: Language; Animal Communication
Link ID: 12344 - Posted: 06.24.2010

Juan Rodriguez 'The book has sold half a million," Daniel Levitin says with equal measures of wonder and boastfulness, referring to This Is Your Brain on Music: The Science of a Human Obsession. He was on his way to a McGill University faculty meeting after an hour and a half of talking about the many ways music -- or what the great avant-garde composer Edgard Varese termed "organized sound" --affects us. The theme is further extrapolated to songcraft in The World in Six Songs: How the Musical Brain Created Human Nature. The book is a meditation on songcraft that he categorizes into six types, conveying friendship, joy, comfort, knowledge, religion and love, copiously illustrated by lyrics he interprets in an affecting mix of scientific, literary and personal viewpoints. "I think this is a better book," he says, "because I found my voice." One wall of his small office at McGill -- where he holds the Bell chair in the psychology of electronic communication -- is stacked with rows of boxed research papers and documents. The opposite wall bears a photo of Levitin with Sting and framed platinum albums (such as Steely Dan's classic Aja), from his days and nights working on record production (for artists including Stevie Wonder and Blue Oyster Cult). His books come with testimonials from George Martin, Bobby McFerrin, Oliver Sacks, New Yorker writer Adam Gopnik, David Byrne and Sting, among others. © 2008 The National Post Company

Keyword: Hearing
Link ID: 12343 - Posted: 06.24.2010

Neuroscience is increasingly relevant to a number of professions and academic disciplines beyond its traditional medical applications. Lawyers, educators, economists and businesspeople, as well as scholars of sociology, philosophy, applied ethics and policy, are incorporating the concepts and methods of neuroscience into their work. Indeed, for any field in which it is important to understand, predict or influence human behavior, neuroscience will play an increasing role. The Penn Neuroscience Boot Camp is designed to give participants a basic foundation in cognitive and affective neuroscience and to equip them to be informed consumers of neuroscience research. For more on the curriculum and goals, click here. Through a combination of lectures, break-out groups, panel discussions and laboratory visits, participants will gain an understanding of the methods of neuroscience and key findings on the cognitive and social-emotional functions of the brain, lifespan development and disorders of brain function. Each lecture will be followed by extensive Q&A. Break-out groups will allow participants to delve more deeply into topics of relevance to their fields. Laboratory visits will include trip to an MRI scanner, an EEG/ERP lab, an animal neurophysiology lab, and a transcranial magnetic stimulation lab. Participants will also have access to an extensive online library of copyrighted materials selected for relevance to the Boot Camp, including classic and review articles and textbook chapters in cognitive and affective neuroscience and the applications of neuroscience to diverse fields.

Keyword: Miscellaneous
Link ID: 12342 - Posted: 12.16.2008

More people with eating disorders could benefit from "talking therapies" which aim to release them from obsessive feelings, say UK researchers. They said a specially-created form of cognitive behavioural therapy might work in four out of five cases. A 154-person American Journal of Psychiatry study, by the University of Oxford, found most achieved "complete and lasting" improvement. At present, the treatment is officially recommended only for bulimia patients. Some statistics suggest that more than a million people in the UK are affected by some kind of eating disorder, the best known types being anorexia nervosa and bulimia. Approximately 40% of those with eating disorders have bulimia, 20% have anorexia, and the remainder have "atypical disorders", which can combine both bulimic and anorexic-type symptoms. The National Institute of Clinical Excellence has backed cognitive behavioural therapy for bulimia, but Professor Christopher Fairburn, the Wellcome Trust funded researcher who led the project, believes his version could help many more people. His study focused on bulimia and "atypical" patients, but excluded those with anorexia. The technique works using a series of counselling sessions which help the person involved to realise the links between their emotions and behaviour, and work out ways to change what they are doing. Professor Fairburn developed two versions specifically for people with eating disorders, one which focused completely on the eating problems, and another, which took a wider view of not only the eating disorder, but also problems with self-esteem which might be contributing to it. Both treatments involved 50-minute outpatient sessions repeated once a week for 20 weeks. (C)BBC

Keyword: Anorexia & Bulimia
Link ID: 12341 - Posted: 12.15.2008

Seven new gene variants discovered by scientists suggest strongly that obesity is largely a mind problem. The findings suggest the brain plays the dominant role in controlling appetite, and that obesity cannot easily be blamed on metabolic flaws. Two international studies, published in Nature Genetics, examined samples from thousands of people for the tiniest genetic changes. Many of the seven key variants seem to be active in the brain. This suggests that the brain's impact on appetite and eating behaviour may be more important that any genetic variation which alters the body's ability to lay down or burn up fat. All seven variants were picked up by a study led by Icelandic company deCODE Genetics, while six of the seven were also identified in a second, independent study by an international team dubbed the Giant consortium. In both cases the researchers scrutinised DNA samples from thousands of people to assess the impact of tiny changes. Each of the variants identified had a small impact on obesity, but a person carrying all of them was typically around 1.5kg - 2kg heavier than average. It is estimated that as much as 70% of the variation in body mass index - a measure of obesity based on height and weight - is down to genetics, rather than environmental factors. Researcher Dr Kari Stefansson, of deCODE Genetics said: "This suggests that as we work to develop better means of combating obesity, we need to focus on the regulation of appetite at least as much as on the metabolic factors of how the body uses and stores energy." Dr Alan Guttmacher, of the US National Human Genome Research Institute, said the research was a major step forward in understanding how the human body regulates weight. (C)BBC

Keyword: Obesity; Genes & Behavior
Link ID: 12340 - Posted: 12.15.2008

GAZA CITY, Gaza Strip - The new drug overtaking the Gaza Strip doesn't stimulate hallucinations or give endurance at the dance club. It merely chills you out, which is exactly what many Gazans say they need. Ruled by Islamic hard-liners from Hamas and locked in by Israel, Gazans can't travel outside the strip, have few places to go for fun, and are faced with a failing economy. Thus the boom in the popularity of tramadol, a painkiller known here by a common brand name, "Tramal." Growing numbers of Gazans have begun using the drug over the past year and a half to take the edge off life in the impoverished seaside strip, pharmacists and residents say. This worries medical personnel, who say the drug can cause dependence. It is a prescription drug in many countries, and the Hamas-run Health Ministry has made efforts to control it, but without much success in a society where medicines available only by prescription elsewhere are often sold over the counter. Tramadol is especially popular among young men. Some down the pills with coffee or dissolve them in tea. Others pop them freely when hanging out with friends. Grooms have been seen passing them out at weddings. "You feel calmness through your whole body, absolute quiet," said one regular user, 27-year-old Bassem, in describing the drug's effect. He, like others interviewed by The Associated Press for this story, refused to give his last name for fear of being arrested as a drug user. © 2008 The Associated Press

Keyword: Drug Abuse
Link ID: 12339 - Posted: 06.24.2010

By DONALD G. McNEIL Jr. D. Carleton Gajdusek, a virologist who won the 1976 Nobel Prize in medicine for his work on the mysterious epidemics now known as prion diseases, died last week in Tromso, Norway. The cause of death is unknown, but Dr. Gajdusek (pronounced GUY-dah-shek) was 85 and had long had congestive heart failure, said Dr. Robert Klitzman, his biographer, who said he had spoken to him about a week ago. He was found in his Tromso hotel room on Friday morning about 24 hours after a manager saw him at breakfast. In later life, Dr. Gajdusek became notorious when he was charged with molesting the many young boys he had adopted in New Guinea and Micronesia and brought to live with him in Maryland. He pleaded guilty to one charge, served a year in prison and left the United States in 1998, dividing his time between Paris, Amsterdam and Tromso. Dr. Gajdusek won the Nobel for his work on kuru, which was slowly wiping out the Fore tribe of New Guinea. Victims descended into trembling and madness before death and, after an autopsy, were found to have brains shot through with spongy holes. In 1957, Dr. Gajdusek — who had searched the Hindu Kush, the Amazon jungle and finally the mountain valleys of New Guinea hoping to find remote tribes with unique diseases to study — realized that the victims had all participated in “mortuary feasts” in the decades before the custom was suppressed in the 1940s by missionaries and the Australian police. Copyright 2008 The New York Times Company

Keyword: Prions
Link ID: 12338 - Posted: 06.24.2010

by Celeste Biever Pictures you are observing can now be recreated with software that uses nothing but scans of your brain. It is the first "mind reading" technology to create such images from scratch, rather than picking them out from a pool of possible images. Earlier this year Jack Gallant and colleagues at the University of California, Berkeley, showed that they could tell which of a set of images someone was looking at from a brain scan. To do this, they created software that compared the subject's brain activity while looking at an image with that captured while they were looking at "training" photographs. The program then picked the most likely match from a set of previously unseen pictures. Now Yukiyasu Kamitani at ATR Computational Neuroscience Laboratories in Kyoto, Japan has gone a step further: his team has used an image of brain activity taken in a functional MRI scanner to recreate a black-and-white image from scratch. "By analysing the brain signals when someone is seeing an image, we can reconstruct that image," says Kamitani. This means that the mind reading isn't limited to a selection of existing images, but could potentially be used to "read off" anything that someone was thinking of, without prior knowledge of what that might be. © Copyright Reed Business Information Ltd.

Keyword: Vision; Sleep
Link ID: 12337 - Posted: 06.24.2010

HELEN BRANSWELL Traumatic brain injuries have become the signature wound of the wars in Afghanistan and Iraq and troops who sustain them face a daunting array of potential medical consequences later on, a report on the issue commissioned by the U.S. Department of Veterans Affairs. The report from the Institute of Medicine – a body that advises the U.S. government on science, medicine and health – said military personnel who sustain severe or even moderate brain injuries may go on to develop Alzheimer's-like dementia or symptoms similar to Parkinson's, a neurodegenerative disease. They face a higher risk of developing seizure disorders and psychoses, problems with social interactions and difficulty holding down a job. Troops who sustain even mild brain injuries are more likely to develop post-traumatic stress disorder (PTSD). And all are at a higher risk of experiencing aggressive behaviour, depression and memory problems. The report urged the U.S. government to ramp up research in the area, saying there is not enough evidence in the medical literature – especially as relates to mild brain injuries – to determine what today's troops face and how best to help them recover from or cope with the health problems they may develop. © Copyright 2008 CTVglobemedia Publishing Inc.

Keyword: Brain Injury/Concussion
Link ID: 12336 - Posted: 06.24.2010

By Rachel Zelkowitz Brainiacs, rejoice! The most sophisticated study on the subject so far suggests that, when it comes to choosing a mate, females value intelligence and creativity independent of a guy's looks. Just what makes men and women attractive to the opposite sex? We don't need science to tell us that a nice body and good personality help. But when it comes to traits such as intelligence and creativity, an experiment or two is useful. Until now, however, most data have come from surveys, often asking abstract questions such as, "How important to you is a man's intelligence?" To gauge how smarts can affect women's mate choices in real-life situations, evolutionary psychologist Mark Prokosch of Elon University in North Carolina and researchers at the University of California, Davis, brought romance back to the laboratory. The team recruited 15 men with a median age of 19 to take the Wechsler Adult Intelligence Scale, a standard intelligence test. The volunteers were then filmed in three separate scenarios designed to reveal intelligence and creativity. They included reading headlines from news agencies such as the BBC, answering an open-ended question such as how the discovery of life on Mars might change their perspective of life on Earth, and responding to queries about why they would make a good date. These tasks might seem random, but previous studies have shown that whether someone stumbles over unfamiliar text or whether he can provide a pithy response to an unexpected question gives clues to his overall intelligence and creativity. The researchers also filmed the men playing Frisbee, so viewers could get a sense of their physical attractiveness. © 2008 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Intelligence
Link ID: 12335 - Posted: 06.24.2010

By Tina Hesman Saey Making decisions about crime and punishment is, it turns out, as complicated as a legal brief. For the first time, scientists have peered into the brains of people who are deciding whether a crime deserves punishment and how severe the penalty should be. Those decisions involve parts of the brain associated with rational thought, but emotion-processing regions weigh in too, a team of law and neuroscience researchers from Vanderbilt University in Nashville, Tenn., show in a new study in the Dec. 11 Neuron. The findings suggest that brain areas active in deciding a harsh punishment for a crime deliberately committed are different than those active when giving the accused some benefit of the doubt. “We’ve identified regions that are jointly involved, but separately deployed to make a legal decision,” says Owen Jones, a professor of law and biology at Vanderbilt who led the study with neuroscientist René Marois. “Our judicial system based on third-party punishment is usually seen as cold and detached as opposed to … punishment by the victim of a crime,” Marois says. The new study shows that emotions play a part in impartial judgment too. Scientists have used functional MRI, or fMRI, before to scan the brains of people who are trying to decide whether to retaliate against someone who has cheated them in an economic game. But the new study is the first to examine which parts of the brain are active when an impartial third party makes decisions about guilt and punishment. © Society for Science & the Public 2000 - 2008

Keyword: Emotions; Brain imaging
Link ID: 12334 - Posted: 06.24.2010

There are signs that the ongoing decline in teen marijuana use in recent years has stalled; however the downward trend in cigarette and alcohol use continues, according to the 2008 Monitoring the Future (MTF) Survey. Results were announced today at a news conference. The MTF survey indicates that marijuana use among eighth, tenth, and twelfth graders, which has shown a consistent decline since the mid-1990s, appears to have leveled off with 10.9 percent of eighth graders, 23.9 percent of tenth graders, and 32.4 percent of twelfth graders reporting past year use. Heightening the concern over this stabilization in use is the finding that, compared to last year, the proportion of eighth graders who perceived smoking marijuana as harmful and the proportion disapproving of its use have decreased. The Monitoring the Future survey — now in its 33rd year — is a series of classroom surveys of eighth, tenth, and twelfth graders conducted by researchers at the University of Michigan under a grant from the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health (NIH), U.S. Department of Health and Human Services (HHS). "The 2008 survey results reinforce the fact that we cannot become complacent in our efforts to persuade teens not to smoke, drink or abuse illicit substances," said HHS Secretary Mike Leavitt. "As long as young people are being exposed to images that make taking drugs seem glamorous, we need to counter them with truthful messages about the risks and consequences of drug abuse."

Keyword: Drug Abuse
Link ID: 12333 - Posted: 06.24.2010