 When it comes to the human brain, even the simplest of acts can be counter-intuitive and deceptively complicated. For example, try stretching your arm.
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| Nerves in the limb send messages back to your brain, but the subjective experience you have of stretching isn’t due to these signals. |
| The feeling that you willed your arm into motion, and the realisation that you moved it at all, are both the result of an area at the back of your brain called the posterior parietal cortex. |
Dualist philosophers like Descartes believed that the mind and consciousness exist outside the physical world, producing our actions by interacting with the physical meat of our brains. The idea has become commonplace, but it’s challenged by neuroscientific studies like this one, which show that the conscious intention to move emerges from electrical activity in neurons, tangible objects that are all too real.
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If they have the number right, its only a thousand fold short of the brain computation power and memory. Almost there…
Computers are lauded for their speed and accuracy, but they don't hold a candle to the human brain when it comes to tackling complex mathematical problems, Dharmendra Modha, director of cognitive computing at the IBM Almaden Research Center, said at today's event. The Defense Advanced Research Projects Agency ( DARPA), the U.S. Defense Department's research arm, last year gave Modha and his colleagues $4.9 million for a project called “SyNAPSE,” through which they are trying to reverse-engineer the brain's computational abilities to better understand its ability to sense, perceive, act, interact, and understand different stimuli. |
“We have no computers today that can begin to approach the awesome power of the human mind,” Modha said. A computer comparable to the human brain, he added, would need to be able to perform more than 38 thousand trillion operations per second [[http://www.petaflop.info/]] and hold about 3,584 terabytes of memory. (IBM's BlueGene supercomputer, one of the worlds' most powerful, has a computational capability of 92 trillion operations per second and 8 terabytes of storage.) |
Although the brain is still not well understood, Modha said, “there is enough quantitative data for us to be able to begin putting together the pieces.” He predicted that by 2018 computers will be able to simulate the workings of the human brain, a breakthrough that will provide researchers with unprecedented insight into how the complex organ operates. |
In addition to boosting computer performance, enhanced understanding of the brain will enable people to communicate directly with machines, whether they are robots or mechanized prosthetic limbs. Primates have already proved that such brain-machine interfaces are possible, Miguel Nicolelis, co-director of Duke University Medical Center's Center for Neuroengineering, said during the conference. The researcher and his colleagues last year successfully implanted electrodes in the brain of a monkey in North Carolina that enabled him to control a robot on a treadmill in Kyoto, Japan. |
Nicolelis and his team have developed a microchip they expect will allow human brains to communicate with robots using only brain signals and enables the bots to return messages directly to the brain, without the use of sight or touch. Nicolelis said that he hopes the technology will be sophisticated enough to implant into a human brain by 2012 and enable a completely quadriplegic patient to walk again. Read more at www.sciam.com |
| An elderly Chinese woman wearing a headset concentrates intensely on a small foam ball and it begins to rise slowly into the air. |
| It’s not magic, but rather the latest game from toy maker Mattel, which allows players to move a ball around an obstacle course by using just their powers of concentration. |
Focusing on the ball causes a fan in the base of the game — called Mind Flex — to start up and lift the ball on a gentle stream of air. Break your concentration and the ball descends. Once a player has the ball in the air they need to try to weave it through hoops, towers and other obstacles. |
Mind Flex relies on EEG technology to measure brain wave activity through a headset equipped with sensors for the forehead and earlobes. The game, which will be available in September for 79.99 dollars, is being displayed by Mattel at the annual Consumer Electronics Show (CES) in Las Vegas. See more at www.physorg.com |
| For those of you perplexed by love’s elusiveness, take heart: Science is on the case. But even if researchers can turn love into peer-reviewed literature, they might not be able to bottle it. |
| “People think we’re going to get a love potion, and that’s nonsense,” said Helen Fisher, a Rutgers University evolutionary anthropologist. “I don’t think they understand how complex the brain is, and what a powerful role experience plays.” |
| Fisher’s comments were prompted by an essay, entitled “Love: Neuroscience reveals all” and published Wednesday in Nature |
| This research shows how a “biochemical chain of events,” |
| produces neurological patterns associated with subjective experiences described as love. |
| Studies on the more-or-less monogamous prairie vole, for example, suggest that a neurotransmitter called oxytocin is important to mate bonding |
| Younger people, it appears, take a dimmer view of the past than their elders, and it might be because they process and retain memories differently |
| Researchers showed 180 pictures to 15 people in their 20s and to 15 older than 65, asking them to rate the pictures as emotionally negative, positive or neutral while their brains were monitored with functional M.R.I |
| After a break of 30 to 45 minutes, they were tested on their ability to recall the pictures |
| The M.R.I. results showed that older people were processing the negative pictures in different parts of the brain from the ones used by the younger people |
| regions used for rational thinking rather than feeling |
| older adults remembered fewer negative pictures |
| “In the emotion detection region of the brain, we saw similar activity in the old and young,” he said. “Older people have preserved emotional reactivity, but they are better able to control those emotions, and this control influences their memory for negative information.”See more at www.nytimes.com |
| The man, a doctor left blind by two successive strokes, refused to take part in the experiment. He could not see anything, he said, and had no interest in navigating an obstacle course ” a cluttered hallway ” for the benefit of science. Why bother? |
| When he finally tried it, though, something remarkable happened. He zigzagged down the hall, sidestepping a garbage can, a tripod, a stack of paper and several boxes as if he could see everything clearly. A researcher shadowed him in case he stumbled. |
| The study, which included extensive brain imaging, is the most dramatic demonstration to date of so-called blindsight, the native ability to sense things using the brain’s primitive, subcortical ” and entirely subconscious ” visual system. See more at www.nytimes.com |
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. |
| 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 worldSee more at www.sciam.com |
| The body image is a mental representation of one’s physical appearance, constructed by the brain from past experiences and present sensations. It is an essential component of self-identity, which, when altered, can have dramatic effects on how one perceives oneself. |
| body image distortions can have bizarre consequences. Otherwise healthy people report that they have always percived a part of their body as feeling “wrong,” and opt to have it removed by amputation; some brain-damaged or psychiatric patients experience alien hand syndrome, in which they deny ownership of a limb, and insist that it is under the control of external forces. |
| a study published recently in the journal Current Biology shows that a simple manipulation of the visual image of one’s body can significantly alter the perception of pain. These findings have important implications for how clinicians manage the treatment of pain.See more at www.sciam.com |
| Researchers at The University of British Columbia have discovered why the brain loses its capacity to re-grow connections and repair itself, knowledge that could lead to therapeutics that “rejuvenate” the brain. |
| The study, published today in The EMBO Journal, identified a set of proteins — calpain and cortactin, which regulate and control the sprouting of neurons — a mechanism known as neural plasticity. |
| Neurons, or nerve cells, process and transmit information by electrochemical signalling and are the core components of the brain and spinal cord. During development, growing neurons are relatively plastic and can sprout new connections, however their plasticity levels drop rapidly as they mature and become integrated into neuronal networks. |
| This discovery is exciting because we now know that neurons haven’t lost their capacity to re-grow connections, but instead are under constant repression by the protein calpainSee more at www.physorg.com |
| Google’s stock is now down more than 50% year to date but the Google guys don’t seem to be concerned. Here’s why |
| Most people think the reason is because Google dominates search. But Google is building a new secret weapon that has more to do with the brain than search. |
| The effort is called MapReduce, a simple yet powerful software program that enables Google to use the Internet to think. |
| MapReduce does what our brains do all the time: It categorizes (Maps) key pieces of information, distributes it across its server farm of PCs, and then eliminates (Reduces) irrelevant data (computers–unlike MapReduce and the brain–soak in everything). |
| Does this sound like the perfect computer? Think again. |
| This is not even your typical computer: one that is stable, logical, and failsafe. Instead, it is error prone, strapped together with Velcro (literally) and unreliable |
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