By Christof Koch What is consciousness? What is this ineffable, subjective stuff—this thing, substance, process, energy, soul, whatever—that you experience as the sounds and sights of life, as pain or as pleasure, as anger or as the nagging feeling at the back of your head that maybe you’re not meant for this job after all. The question of the nature of consciousness is at the heart of the ancient mind-body problem. How does subjective consciousness relate to the objective universe, to matter and energy? Consciousness is the only way we experience the world. Without it, you would be like a sleepwalker in a deep, dreamless sleep, acting in the world, speaking, having babies, but without feeling anything. You would feel nothing, nada, nichts, rien. Indeed, in the most famous deduction of Western thought, philosopher and mathematician René Descartes concluded that because he was conscious he existed. That was his only unassailable proof that he wasn’t just a chimera. Maybe he didn’t have the body he thought he had, maybe he had fake memories (premonitions of The Matrix), but because he was conscious he must exist. Yet the questions go on. Are only people conscious? What about a fetus? What about a neurological patient in a persistent vegetative state, such as Terri Schiavo (who died in 2005), who can’t do much more than open and close her eyes? Although many are willing to accord sentience, consciousness, to our beloved cats and dogs, what about apes, monkeys, whales, mice, bees and all the other critters on the planet? Can a fly be conscious? What about artificial consciousness? Is your cool iPhone sentient? Can machines ever become conscious, as is widely assumed in so many science-fiction novels and movies? © 1996-2008 Scientific American Inc.

Keyword: Attention; Emotions
Link ID: 12252 - Posted: 06.24.2010

By Susana Martinez-Conde and Stephen L. Macknik Scientists did not invent the vast majority of visual illusions. Rather, they are the work of visual artists, who have used their insights into the workings of the visual system to create visual illusions in their pieces of art. We have previously pointed out in our essays that, long before visual science existed as a formal discipline, artists had devised techniques to “trick” the brain into thinking that a flat canvas was three-dimensional, or that a series of brushstrokes in a still life was in fact a bowl of luscious fruit. Thus the visual arts have sometimes preceded the visual sciences in the discovery of fundamental vision principles, through the application of methodical—although perhaps more intuitive—research techniques. In this sense, art, illusions and visual science have always been implicitly linked. It was only with the birth of the op art (for “optic art”) movement that visual illusions became a recognized art form. The movement arose simultaneously in Europe and the U.S. in the 1960s, and in 1964 Time magazine coined the term “op art.” This style became hugely popular after the Museum of Modern Art in 1965 held an exhibition called “The Responsive Eye.” In it, op artists explored many aspects of visual perception, such as the relations between geometrical shapes, variations on “impossible” figures that could not occur in reality, and illusions concerning brightness, color and shape perception. But “kinetic,” or motion, illusions drew particular interest. In these eye trick, stationary patterns give rise to the powerful but subjective perception of (illusory) motion. © 1996-2008 Scientific American Inc.

Keyword: Vision
Link ID: 12251 - Posted: 06.24.2010

by David Robson WOMEN may be fed up with being stereotyped as the chattier sex, but the cliche turns out to be true - in female-centric monkey groups at least. The gossipy nature of female macaques also adds weight to the theory that human language evolved to forge social bonds. Many researchers think that language replaced grooming as a less time-consuming way of preserving close bonds in ever-growing societies. Nathalie Greeno and Stuart Semple from Roehampton University in London hypothesised that if this was true then in species of animals with large social networks, such as macaques, vocal exchanges should be just as important as grooming. The duo listened to a group of 16 female and eight male macaques living on Cayo Santiago island off Puerto Rico for three months. They counted the grunts, coos and girneys - friendly chit-chat between two individuals - while ignoring calls specific to the presence of food or a predator. The team found that females made 13 times as many friendly noises as males. "The results suggest that females rely on vocal communication more than males due to their need to maintain the larger social networks," Greeno says. Females rely on vocal communication more than males due to their need to maintain larger social networks © Copyright Reed Business Information Ltd.

Keyword: Language; Evolution
Link ID: 12250 - Posted: 06.24.2010

The dietary supplement Ginkgo biloba was found to be ineffective in reducing the development of dementia and Alzheimer's disease in older people, according to a study published in the Journal of the American Medical Association1. Researchers led by Steven T. DeKosky, M.D., formerly of the University of Pittsburgh, vice president and dean of the School of Medicine at the University of Virginia in Charlottesville, conducted the trial known as the Ginkgo Evaluation of Memory (GEM) study at four clinical sites over the course of 8 years. GEM is the largest clinical trial ever to evaluate ginkgo's effect on the occurrence of dementia. This research was co-funded by five components of the National Institutes of Health (NIH): National Center for Complementary and Alternative Medicine (NCCAM); National Institute on Aging (NIA); National Heart, Lung, and Blood Institute; National Institute of Neurological Disorders and Stroke, and the Office of Dietary Supplements. "We have made enormous progress in understanding the basic mechanisms involved in Alzheimer's disease, and we continue to pursue a vigorous program to translate what we know into the development and testing of new potential therapies for this devastating disease," said Richard Hodes, M.D., director of the NIA. "However, it is disappointing that the dietary supplement tested in this study had no effect in preventing Alzheimer's disease."

Keyword: Alzheimers; Learning & Memory
Link ID: 12249 - Posted: 11.20.2008

-- Biologists on Wednesday explained how the larvae of marine zooplankton can see with just two cells, using what is believed to be the world's simplest vision system. Zooplankton are tiny creatures such as copepods and krill that drift in the ocean's water columns, swimming up from the depths towards the light in order to graze on marine plants called phytoplankton near the surface. This movement, called phototaxis, is the biggest biomass displacement in the world. In a study published by the British-based journal Nature, European scientists looked at the larvae of the marine ragworm Platyneris dumerilii to try to explain how plankton are able to do the phototaxis trick. The larva has just two eye cells, consisting of a pigment cell and a light-sensitive cell, say the investigators. The cells are unable to form images but enable the plankton to sense the difference between light and dark and send appropriate signals to its swimming mechanism, say the investigators. © 2008 Discovery Communications, LLC.

Keyword: Vision; Evolution
Link ID: 12248 - Posted: 06.24.2010

by Ewen Callaway The female brain has a clever way of mitigating the stress experienced during menstruation: it flip-flops. The region of the brain used for coping with stress flips to the opposite side of the brain during a woman's period - from an area linked to negative emotion to one that usually deals with cheerier thoughts. Such a change could help women cope with the hormonal maelstrom going on in their bodies without causing huge behavioural shifts. Oestrogen levels levels, in particular, plummet around menstruation. Jen-Chuen Hsieh, a neuroscientist at National Yang-Ming University in Taipei, Taiwan, and colleagues studied 14 women using a magnetoencephalograph ¬ a machine that measures magnetic waves created by brain activity. All their subjects were right-handed, to ensure that the left-right orientation of their brains matched. When the women were shown frightening images, they normally triggered activity in the right half of the women's brains. This side of the brain tends to process negative feelings, such as anxiety. During the women's menstrual periods, however, the images activated areas in the left half of their brains, which handles positive emotions. © Copyright Reed Business Information Ltd.

Keyword: Stress; Hormones & Behavior
Link ID: 12247 - Posted: 06.24.2010

Scientists have identified a molecule which could be key to understanding the cause of motor neurone disease (MND) and other neurodegenerative disorders. The Proceedings of the National Academy of Sciences study raise the hope of new treatments being developed. The London-based team showed the molecule, Wnt3, plays a key role in establishing connections between nerve cells and the muscles they control. These connections become progressively weaker in MND patients. Without properly-formed connections - or synapses - the muscle cannot receive the nerve signal that tells it to contract. This results in the muscle weakness that is typical of MND. However, scientists have not been clear how synapses are formed in normal circumstances and this has made it very difficult to pin down what goes wrong in MND. The researchers, from University College London and King's College London, identified Wnt3 as key to the process. It assists a second molecule, called Agrin, which co-ordinates construction of the connection - or synapse. Lead researcher Professor Patricia Salinas said: "The work we are publishing today puts an important piece of the puzzle in place and offers up a new possibility for developing drugs to treat MND and other neurodegenerative diseases. "If we can build up a thorough picture to show how synapses are normally formed between nerves and muscles we can start to look for any elements that aren't working properly in people with MND. This might also lead to strategies for nerve repair after an injury." (C)BBC

Keyword: ALS-Lou Gehrig's Disease
Link ID: 12246 - Posted: 11.18.2008

A handful of people reach old age with razor-sharp brains. Scientists call them "super aged." But what makes them special? In a new study, researchers examined the brains of five dead people who were considered super aged because after age 80 they had performed higher on memory tests than others their age. The scientists compared these brains to those from some "normal," non-demented elderly folks who had died. Story continues below ↓advertisement | your ad here The super aged brains had fewer fiber-like tangles than the brains of people who had aged normally. The tangles consist of a protein called tau that accumulates inside brain cells and is thought to eventually kill them, the researchers explained in what they're calling a preliminary finding. Tangles are found in at least moderate numbers in the brains of all elderly people, but they are more prevalent in the brains of Alzheimer's disease patients. "It was always assumed that the accumulation of these tangles is a progressive phenomenon through the aging process. But we are seeing that some individuals are immune to tangle formation and that the presence of these tangles seems to influence cognitive performance," said Changiz Geula, principal investigator of the study and a research professor of neurology at the Cognitive Neurology and Alzheimer's Disease Center at Northwestern's Feinberg School in Illinois. © 2008 LiveScience.com.

Keyword: Alzheimers
Link ID: 12245 - Posted: 06.24.2010

By JOHN TIERNEY Last year, a team of researchers at Harvard made headlines with an experiment testing unconscious bias at hospitals. Doctors were shown the picture of a 50-year-old man — sometimes black, sometimes white — and asked how they would treat him if he arrived at the emergency room with chest pains indicating a possible heart attack. Then the doctors took a computer test intended to reveal unconscious racial bias. The doctors who scored higher on the bias test were less likely than the other doctors to give clot-busting drugs to the black patients, according to the researchers, who suggested addressing the problem by encouraging doctors to test themselves for unconscious bias. The results were hailed by other psychologists as some of the strongest evidence that unconscious bias leads to harmful discrimination. But then two other researchers, Neal Dawson and Hal Arkes, pointed out a curious pattern in the data. Even though most of the doctors registered some antiblack bias, as defined by the researchers, on the whole doctors ended up prescribing the clot-busting drugs to blacks just as often as to whites. The doctors scoring low on bias had a pronounced preference for giving the drugs to blacks, while high-scoring doctors had a relatively small preference for giving the drugs to whites — meaning that the more “biased” doctors actually treated blacks and whites more equally. Copyright 2008 The New York Times Company

Keyword: Emotions
Link ID: 12244 - Posted: 06.24.2010

By BENJAMIN BRODY, M.D “Has anything changed since the treatments began?” I ask the patient, as he lies down on a stretcher in the ECT suite. The anesthesiologist places an IV line in his arm and checks his vital signs. My attending psychiatrist adjusts the machine that delivers the electric stimulus. I’m a psychiatry intern, and this is my electroconvulsive therapy rotation. I’m here to watch and learn. “My cellphone always has a great charge,” the patient deadpans. If this were a friend or colleague, I would laugh easily. But this is a patient I barely know. He has bipolar disorder, a previous suicide attempt and a history of bizarre, impulsive behavior. In that context, his joke just feels inappropriate and overly familiar. I’m taken aback. Is it O.K. to laugh, I wonder? An intern, with years of experience being inexperienced, I quickly glance around to take stock of the room. The nursing assistant laughs and the anesthesiologist grins broadly. The attending psychiatrist remains stone-faced, and says, “Clearly he’s improving.” As the anesthesiologist injects a sedative, a telephone rings. Everyone’s hands are occupied; the ringing continues. Just as the patient starts to drift off, he looks over at me and says: “Can you get that? It might be the governor calling to stay my execution.” Copyright 2008 The New York Times Company

Keyword: Depression; Schizophrenia
Link ID: 12243 - Posted: 06.24.2010

By Jayne Lytel Paging through 176 MRI scans of my 9-year-old's brain on my home computer, I discovered a button that let me play them as a movie. Gray swirls burst onto the screen, dissolving into one another and revealing a new set of patterns. Beams of light faded in and out, some curving and traveling around the different regions of his brain. I saw the squiggly folds of his cerebral cortex, the gray matter that is the center of human intelligence. These scans, the most intimate pictures I had ever seen of my son, Leo, may help researchers understand what's going on in his head -- and relieve him of a diagnosis that I have devoted several years to helping him overcome. Leo, identified as No. C1059, underwent the scans as part of a research study at the Olin Neuropsychiatry Research Center at Hartford Hospital in Connecticut. He was thrilled to earn $200 for taking part. I smiled along with him, because I could remember the days when he had a limited range of emotions, and pride was not one of them. The study is examining 35 children, ranging in age from 8 to 17, who once had an autism-spectrum diagnosis but no longer do. Leo was invited to participate based on how I had described changes in his behavior and communication skills since he was given an autism diagnosis seven years ago. It is one of several studies underway to clarify the experiences of a growing number of children who are apparently emerging from autism and its related disorders to function almost indistinguishably from their peers; it aims to reveal whether it is indeed possible to recover from autism. © 2008 The Washington Post Company

Keyword: Autism
Link ID: 12242 - Posted: 06.24.2010

They say "romantic love" was invented by the troubadors of the Middle Ages. They also say it doesn't last. But Rutgers University anthropologist Helen Fisher and colleagues reported today that functional brain imaging studies show that being "in love" transcends both culture and time. The researchers imaged the brains of 17 young Americans and 17 young Chinese who had been in intense love relationships for 6 months. The team compared how the volunteers' brains reacted to a photograph of a loved one versus a photo of someone they didn't know. When viewing a loved one, the brains of the volunteers registered activity in "several regions associated with addiction," said Fisher--notably in the ventral tegmental area, a region of the brain stem that are rich in receptors for dopamine, the chief actor in the brain's "reward circuit". The team also rounded up 17 people of both sexes, aged 40 to 65, married at least 20 years, who said they were still "in love" with their spouses. The researchers found that the same areas were activated in most of them on viewing a photo of their spouse. But longterm romantic love also stirred up brainstem regions rich in serotonin (see pic) and a chemical called vasopressin, which is associated with monogamy in voles. The upshot is that the long-marrieds have the best of both worlds--they are still in love, but the "the obsession, mania and anxiety" of newly-hatched infatuation "is replaced by calm," said Fisher. © 2008 American Association for the Advancement of Science. All Rights Reserved.

Keyword: Sexual Behavior; Emotions
Link ID: 12241 - Posted: 06.24.2010

Epigenetics has been a hot topic at this year's meeting. When I ducked out of a symposium devoted to it on Saturday afternoon to catch another talk, by the time I got back the room was jam packed and a convention center employee was turning people away. "If the fire marshal comes we'll be in big trouble," she said. There was only slightly more elbow room at this afternoon's press conference, where half a dozen researchers described their recent work investigating the possible roles of epigenetic mechanisms in everything from learning and memory to problems such as obesity, drug addiction and anxiety. In a nutshell, epigenetics means altering gene expression without messing with DNA sequences. It includes DNA methylation, a chemical alteration to DNA that prevents genes from being read out to make proteins, and histone deacetylation, which accomplishes the same thing by keeping DNA strands tightly wound around spool-like histone proteins. Epigenetics has been a growing area of exploration in cancer biology over the last 20 years. Drugs that inhibit histone deacetylation, for example, have shown promise as cancer-fighting drugs. Relatively little is known about the role of epigenetic mechanisms in the brain, but researchers described several intriguing findings at the press conference. Among them: Tracy Bale of the University of Pennsylvania in Philadelphia presented findings suggesting that high-fat diets during pregnancy can increase the body size of subsequent generations via epigenetic mechanisms in mice. © 2008 American Association for the Advancement of Science. All Rights Reserved.

Keyword: Learning & Memory; Genes & Behavior
Link ID: 12240 - Posted: 06.24.2010

Ashley Yeager Scientists whose work came under scrutiny during a political debate about work funded by the US National Institutes of Health (NIH) in Bethesda, Maryland, censored their own later work, a new study has found1. In July 2003, former congressman Patrick Toomey (Republican, Pennsylvania) argued that NIH grants funding studies on certain types of sexual behaviour were less worthy of taxpayer dollars than those on devastating diseases. He proposed an amendment to the 2004 NIH appropriations bill to revoke funding for five grants — four of which examined sexual behaviour. Toomey's amendment was defeated by two votes, but after a congressional investigation later in 2003, NIH director Elias Zerhouni was sent a list of 250 grants by 157 scientists, most of which were for studies on sexual behaviour and drug use. Republicans involved in the investigation said that the list was sent accidentally. Zerhouni nonetheless investigated all the grants on the list and later wrote to Congress defending the studies. Now, Joanna Kempner, a sociologist at Rutgers University in Piscataway, New Jersey, has surveyed and interviewed many of the principal investigators whose grants came under scrutiny. She has found that many of them subsequently used less-controversial language and, in some cases, changed the focus of their work to avoid such areas altogether. © 2008 Nature Publishing Group

Keyword: Sexual Behavior
Link ID: 12239 - Posted: 06.24.2010

By Laura Sanders WASHINGTON — New research on brain activity confirms that people can be madly in love with each other long after the honeymoon is over. Researchers led by Bianca Acevedo at the Albert Einstein College of Medicine in New York wanted to know if romantic love — or at least the brain activity it triggers — could last in a long-term relationship. To everyone’s relief, the answer is yes. The group presented its results November 16 at the annual meeting of the Society for Neuroscience. The new data suggest that people who have been madly in love for an average of 21 years maintain activation in a brain region associated with early-stage love. “We now have physiological evidence that romantic love can last,” says coauthor Helen Fisher, a biological anthropologist from Rutgers University in New Brunswick, N.J. Most couples who have been together for many years experience a change from a frenetic, obsessive love to something more subdued and comfortable, says study coauthor Lucy Brown of Albert Einstein College of Medicine. But the researchers noticed a small group of outliers who had been with the same person many years and claimed to be as much in love as they were during the exciting early days of their relationship. Since that earlier study in 2005 using functional MRI brain imaging, the researchers knew that a certain part of the brain called the ventral tegmental area was activated when people who had been in love for relatively short times — an average of seven months — saw pictures of their sweethearts. © Society for Science & the Public 2000 - 2008

Keyword: Sexual Behavior; Emotions
Link ID: 12238 - Posted: 06.24.2010

by Alison Motluk RATS with breathing problems caused by damage to their nerves have had normal breathing restored by bursts of visible light aimed onto the spinal cord. This achievement raises hopes that a miniature light source implanted near the spine might one day allow people with similar injuries to breathe normally. In 2005, Ed Boyden at the Massachusetts Institute of Technology infected neurons in Petri dishes with viruses carrying the ChR2 gene, which codes for a light-sensitive protein called channelrhodopsin-2. The neurons started expressing the protein, and this allowed the researchers to use pulses of light to control when the neurons fired (Nature Neuroscience, vol 8, p 1263). "The nerve cells think they are photoreceptors," says neuroscientist Jerry Silver at Case Western Reserve University in Cleveland, Ohio. Silver has now taken things a step further with a study to investigate how this light-operated neuronal switch might be used to restore function lost as a result of nerve damage. His team cut part way through the spinal cords of rats at the second vertebra from the top, where the neck pivots, severing the connection between the spinal cord and the nerves that control one side of the diaphragm. This prevented messages from the brain getting to the diaphragm, leaving the animals with problems breathing. Similar injuries are the leading cause of death in people with spinal cord damage. © Copyright Reed Business Information Ltd

Keyword: Regeneration
Link ID: 12237 - Posted: 06.24.2010

Some tastes--like blue cheese or green olives--are "acquired." But can we conquer our aversion to a food before we even taste it for the first time? Neuroscientist Donald Katz at Brandeis University has shown that it can happen with rats. Rats like sweet tastes best of all. They also like salt. They dislike sour, and they hate bitter. Armed with this knowledge, Katz and colleagues decided to see if they could get the creatures to change their minds about bitter cocoa if they met a pal who seemed to like the stuff. First the researchers got a rat hungry enough that it would be willing to nibble at some raw cocoa. Then they put another rat in with it so rat number 2 could smell the first rat's breath. Finally, the researchers placed the second rat in a cage with two unfamiliar and not particularly appetizing dishes to choose from. Despite their innate aversion to bitter taste, the rats went for the cocoa. Electrode recordings of nerve-firing in the taste circuit showed that the test rats actually altered their evaluation of the cocoa. Taste is evaluated by the brain in three stages: in the first milliseconds, the substance is detected; then it's identified; then the amygdala, the seat of the emotions, sends a message to the cortex telling it whether the taste is noxious or palatable. © 2008 American Association for the Advancement of Science.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 12236 - Posted: 06.24.2010

Even male zebrafinches need a bit of inspiration to do their best work. In her lecture here Saturday night, University of California, San Francisco neuroscientist Allison Doupe described how male finches tighten up their performance when a female is in view. With no one around, a male zebrafinch is liable to botch a few notes in his well-practiced song: sometimes he's a little flat, sometimes a little sharp. But with a fine-feathered female listening from a neighboring cage, he's more likely to hit all the right notes. Doupe's lab has been investigating the underlying neurophysiology, and she thinks this line of study may ultimately help clarify the function of the basal ganglia--a part of the brain that's crucial for learning skilled movements and one that's affected by several neuropsychiatric disorders. In one experiment, Mimi Kao in Doupe's lab used microelectrodes to record the activity of neurons in a brain region called LMAN, a component of the avian basal ganglia. When a male finch sang to a female, LMAN neurons fired in a predictable pattern, with individual neurons firing when he sang a particular element of the song. But when the same male sang on his own, the pattern deteriorated and became less precise--much like his song. When it comes to singing, Doupe suspects that the male zebrafinch brain has two modes: a performance mode, in which he tries to nail every note, and an "exploratory" or "singing in the shower" mode, in which he loosens up a bit and lets more variability creep in. © 2008 American Association for the Advancement of Science.

Keyword: Language; Sexual Behavior
Link ID: 12235 - Posted: 06.24.2010

Older "overlooked" treatments for irritable bowel syndrome may end up being the best option for patients, research suggests. Fibre, anti-spasmodic drugs and peppermint oil were all found to be effective in a review of the evidence. Guidelines on IBS should be updated in light of the findings, the researchers say in the British Medical Journal. A UK expert said there had been a general feeling among doctors that the therapies "didn't work". Between 5% and 20% of the population is estimated to suffer from IBS which is characterised by abdominal pain and an irregular bowel habit. The exact cause of the condition is unknown and recommendations for treatment include dietary advice, antidepressants and alternative therapies. Fibre, antispasmodics and peppermint oil are used to treat IBS, but evidence of their effectiveness is unclear because of conflicting results from studies, the researchers said. They have also been overlooked because of the focus on newer more expensive drugs which ended up being withdrawn due to lack of efficacy and safety concerns, they added. By trawling through all the studies comparing the therapies with dummy pills or no treatment, the researchers were able to look at data from 2,500 adult patients with IBS. Fibre, antispasmodics and peppermint oil were all found to be effective, with doctors needing to treat 11, 5 and 2.5 patients, respectively for one patient to benefit. Insoluble fibre such as bran was not beneficial; only isphaghula husk - a soluble form of fibre - significantly reduced symptoms. Hyoscine - extracted from the cork wood tree - was the most successful antispasmodic drug looked at and should be the first choice, the researchers said. Out of all three treatments, peppermint oil seemed to come out on top. (C)BBC

Keyword: Stress
Link ID: 12234 - Posted: 11.15.2008

A new Homo erectus fossil suggests that females had large, wide pelvises in order to deliver large-brained babies. Being born with a larger brain meant our ancestor became independent far more quickly than modern human infants. The new finding, published in Science magazine, conflicts with earlier ideas that suggest they had a tall, thin body shape adapted for running. Homo erectus is thought to be the first human-like creature to move out of Africa to colonise the world. The now extinct hominid species may also have been the first to control fire. The near-complete 1.4 million-year-old female pelvis was found near Gona in northern Ethiopia. As it was pieced together, the archaeologists were struck by the unusual width of the pelvis. Scott Simpson, a palaeontologist from Case Western Reserve University in Cleveland, Ohio, US, was one of those who made the discovery. "Proportionally her hips are wider than those of modern humans," he says. BBC © MMVIII

Keyword: Evolution
Link ID: 12233 - Posted: 06.24.2010