Traces of the past: Computer algorithm able to 'read' memories - 0 views
-
To explore how such memories are recorded, the researchers showed ten volunteers three short films and asked them to memorise what they saw. The films were very simple, sharing a number of similar features - all included a woman carrying out an everyday task in a typical urban street, and each film was the same length, seven seconds long. For example, one film showed a woman drinking coffee from a paper cup in the street before discarding the cup in a litter bin; another film showed a (different) woman posting a letter. The volunteers were then asked to recall each of the films in turn whilst inside an fMRI scanner, which records brain activity by measuring changes in blood flow within the brain. A computer algorithm then studied the patterns and had to identify which film the volunteer was recalling purely by looking at the pattern of their brain activity. The results are published in the journal Current Biology. "The algorithm was able to predict correctly which of the three films the volunteer was recalling significantly above what would be expected by chance," explains Martin Chadwick, lead author of the study. "This suggests that our memories are recorded in a regular pattern." Although a whole network of brain areas support memory, the researchers focused their study on the medial temporal lobe, an area deep within the brain believed to be most heavily involved in episodic memory. It includes the hippocampus - an area which Professor Maguire and colleagues have studied extensively in the past. They found that the key areas involved in recording the memories were the hippocampus and its immediate neighbours. However, the computer algorithm performed best when analysing activity in the hippocampus itself, suggesting that this is the most important region for recording episodic memories. In particular, three areas of the hippocampus - the rear right and the front left and front right areas - seemed to be involved consistently across all participants. The rear right area had been implicated in the earlier study, further enforcing the idea that this is where spatial information is recorded. However, it is still not clear what role the front two regions play.
-
Computer programs have been able to predict which of three short films a person is thinking about, just by looking at their brain activity. The research, conducted by scientists at the Wellcome Trust Centre for Neuroimaging at UCL (University College London), provides further insight into how our memories are recorded.
A better genetic test for autism - 2 views
-
"A large study from Children's Hospital Boston and the Boston-based Autism Consortium finds that a genetic test that samples the entire genome, known as chromosomal microarray analysis, has about three times the detection rate for genetic changes related to autism spectrum disorders (ASDs) than standard tests. Publishing in the April issue of Pediatrics (and online March 15), the authors urge that CMA become part of the first-line genetic work-up for ASDs."
Everything We Knew About Human Vision is Wrong: Author Mark Changizi Tells Us... - 0 views
-
Our funny primate variety of color vision turns out to be optimized for seeing the physiological modulations in the blood in the skin that underlies our primate color signals.
-
For theoretical neurobiologist and author Mark Changizi, "why" has always been more interesting than "how." While many scientists focus on the mechanics of how we do what we do, his research aims to grasp the ultimate foundations underlying why we think, feel and see as we do. Guided by this philosophy, he has made important discoveries on why we see in color, why we see illusions, why we have forward-facing eyes, why letters are shaped as they are, why the brain is organized as it is, why animals have as many limbs and fingers as they do, and why the dictionary is organized as it is.
YouTube - Sam Harris SALT - 2 views
-
December 9th, 02005 - Sam Harris"The View From The End Of The World"This is an audio only presentation. This talk took place in the Conference Center Golden Gate Room, San Francisco. Quote: With gentle demeanor and tight argument, Sam Harris carried an overflow audience into the core of one of the crucial issues of our time: What makes some religions lethal? How do they employ aggressive irrationality to justify threatening and controlling non-believers as well as believers? What should be our response? Harris began with Christianity. In the US, Christians use irrational arguments about a soul in the 150 cells of a 3-day old human embryo to block stem cell research that might alleviate the suffering of millions. In Africa, Catholic doctrine uses tortured logic to actively discourage the use of condoms in countries ravaged by AIDS. "This is genocidal stupidity," Harris said. Faith trumps rational argument. Common-sense ethical intuition is blinded by religious metaphysics. In the US, 22% of the population are CERTAIN that Jesus is coming back in the next 50 years, and another 22% think that it's likely. The good news of Christ's return, though, can only occur following desperately bad news. Mushroom clouds would be welcomed. "End time thinking," Harris said, "is fundamentally hostile to creating a sustainable future." Harris was particularly critical of religious moderates who give cover to the fundamentalists by not challenging them. The moderates say that all is justified because religion gives people meaning in their life. "But what would they say to a guy who believes there's a diamond the size of a refrigerator buried in his backyard? The guy digs out there every Sunday with his family, cherishing the meaningthe quest gives them." "I've read the books," Harris said. "God is not a moderate." The Bible gives strict instructions to kill various kinds of sinners, and their relatives, and on occasion their entire towns. Yet slavery is challenged nowhere in the New or
Peak Oil and a Changing Climate | The Nation - 2 views
-
Peak Oil is the point at which petroleum production reaches its greatest rate just before going into perpetual decline. In "Peak Oil and a Changing Climate," a new video series from The Nation and On The Earth productions, radio host Thom Hartmann explains that the world will reach peak oil within the next year if it hasn't already. As a nation, the United States reached peak oil in 1974, after which it became a net oil importer. Bill McKibben, Noam Chomsky, Nicole Foss, Richard Heinberg and the other scientists, researchers and writers interviewed throughout "Peak Oil and a Changing Climate" describe the diminishing returns our world can expect as it deals with the consequences of peak oil even as it continues to pretend it doesn't exist. These experts predict substantially increased transportation costs, decreased industrial production, unemployment, hunger and social chaos as the supplies of the fuels on which we rely dwindle and eventually disappear. Chomsky urges us to anticipate the official response to peak oil based on how corporations, news organizations and other institutions have responded to global warming: obfuscation, spin and denial. James Howard Kunstler says that we cannot survive peak oil unless we "come up with a consensus about reality that is consistent with the way things really are." This documentary series hopes to help build that consensus. Click here to watch the introductory video, and check back here for new videos each Wednesday.
New theories reveal the nature of numbers - 0 views
-
For centuries, some of the greatest names in math have tried to make sense of partition numbers, the basis for adding and counting. Many mathematicians added major pieces to the puzzle, but all of them fell short of a full theory to explain partitions. Instead, their work raised more questions about this fundamental area of math. Emory mathematician Ken Ono is unveiling new theories that answer these famous old questions.
Quantum physics first: Physicists measure without distorting - 1 views
-
With this new experiment, the researchers have succeeded for the first time in experimentally reconstructing full trajectories which provide a description of how light particles move through the two slits and form an interference pattern. Their technique builds on a new theory of weak measurement that was developed by Yakir Aharonov's group at Tel Aviv University. Howard Wiseman of Griffith University proposed that it might be possible to measure the direction a photon (particle of light) was moving, conditioned upon where the photon is found. By combining information about the photon's direction at many different points, one could construct its entire flow pattern ie. the trajectories it takes to a screen.
Graphene may reveal the grain of space-time - physics-math - 13 May 2011 - New Scientist - 1 views
-
COULD the structure of space and time be sketched out inside a cousin of plain old pencil lead? The atomic grid of graphene may mimic a lattice underlying reality, two physicists have claimed, an idea that could explain the curious spin of the electron. Graphene is an atom-thick layer of carbon in a hexagonal formation. Depending on its position in this grid, an electron can adopt either of two quantum states - a property called pseudospin which is mathematically akin to the intrinsic spin of an electron. Most physicists do not think it is true spin, but Chris Regan at the University of California, Los Angeles, disagrees. He cites work with carbon nanotubes (rolled up sheets of graphene) in the late 1990s, in which electrons were found to be reluctant to bounce back off these obstacles. Regan and his colleague Matthew Mecklenburg say this can be explained if a tricky change in spin is required to reverse direction. Their quantum model of graphene backs that up. The spin arises from the way electrons hop between atoms in graphene's lattice, says Regan. So how about the electron's intrinsic spin? It cannot be a rotation in the ordinary sense, as electrons are point particles with no radius and no innards. Instead, like pseudospin, it might come from a lattice pattern in space-time itself, says Regan. This echoes some attempts to unify quantum mechanics with gravity in which space-time is built out of tiny pieces or fundamental networks (Physical Review Letters, vol 106, p 116803). Sergei Sharapov of the National Academy of Sciences of Ukraine in Kiev says that the work provides an interesting angle on how electrons and other particles acquire spin, but he is doubtful how far the analogy can be pushed. Regan admits that moving from the flatland world of graphene to higher-dimensional space is tricky. "It will be interesting to see if there are other lattices that give emergent spin," he says.
The Loneliest Plant In The World : Krulwich Wonders… : NPR - 1 views
-
When a cycad is ready to reproduce, it grows a large colorful cone, rich with pollen or seed. It signals its readiness by radiating heat or sending out attractive odors to pollinators, who travel back and forth. Once fertilized, the seed-rich cone is ripped apart by hungry seed carriers (who've included over the years, not just birds and insects, but dinosaurs, pterosaurs, bats; these trees have been eaten by just about everybody). But what if you can't find a mate? The tree in London (and its clones that are now growing in botanical gardens all over the world) is a male. It can make pollen. But it can't make the seeds. That requires a female. Researchers have wandered the Ngoya forest and other woods of Africa, looking for an E. woodii that could pair with the one in London. They haven't found a single other specimen. They're still searching. Unless a female exists somewhere, E. woodii will never mate with one of its own. It can be cloned. It can have the occasional fling with a closely related species. Hybrid cycads are sold at plant stores, but those plants aren't the real deal. The tree that sits in London can't produce a true offspring. It sits there, the last in its long line, waiting for a companion that may no longer exist.
Artificial grammar reveals inborn language sense, study shows - 1 views
-
ScienceDaily (May 13, 2011) - Parents know the unparalleled joy and wonder of hearing a beloved child's first words turn quickly into whole sentences and then babbling paragraphs. But how human children acquire language-which is so complex and has so many variations-remains largely a mystery. Fifty years ago, linguist and philosopher Noam Chomsky proposed an answer: Humans are able to learn language so quickly because some knowledge of grammar is hardwired into our brains. In other words, we know some of the most fundamental things about human language unconsciously at birth, without ever being taught.
The Best Thing Happened to Party People Like Me - 1 views
I really have my doubts when I first heard about herbal highs and legal weed. I said "there is no such thing" but everything changed when I tried Kronic original. True to its promise, it gives the ...
New MRSA superbug discovered in cows' milk - health - 03 June 2011 - New Scientist - 1 views
-
A new strain of MRSA has been identified in cows' milk and in people, but don't stop drinking milk - the bug is killed off in pasteurisation. However, the strain evades detection by standard tests used by some hospitals to screen for MRSA (methicillin-resistant Staphylococcus aureus), potentially putting people at risk. Laura Garcia Alvarez, then at the University of Cambridge, and colleagues were studying infections in British cows when they discovered antibiotic-resistant bacteria that they thought were MRSA. However, tests failed to identify the samples as any known strains of the superbug. Sequencing the mystery bacteria's genomes revealed a previously unknown strain of MRSA with a different version of a gene called MecA. The new strain was also identified in samples of human MRSA, and is now known to account for about 1 per cent of human MRSA cases.
Reverse-engineering the infant mind | KurzweilAI - 0 views
-
A new study by MIT shows that babies can perform sophisticated analyses of how the physical world should behave. The scientists developed a computational model of infant cognition that accurately predicts infants' surprise at events that violate their conception of the physical world. The model, which simulates a type of intelligence known as pure reasoning, calculates the probability of a particular event, given what it knows about how objects behave. The close correlation between the model's predictions and the infants' actual responses to such events suggests that infants reason in a similar way, says Josh Tenenbaum, associate professor of cognitive science and computation at MIT.
First 'living' laser made from kidney cell - physics-math - 12 June 2011 - New Scientist - 0 views
-
It's not quite Cyclops, the sci-fi superhero from the X-Men franchise whose eyes produce destructive blasts of light, but for the first time a laser has been created using a biological cell. The human kidney cell that was used to make the laser survived the experience. In future such "living lasers" might be created inside live animals, which could potentially allow internal tissues to be imaged in unprecedented detail. It's not the first unconventional laser. Other attempts include lasers made of Jell-O and powered by nuclear reactors (see box below). But how do you go about giving a living cell this bizarre ability? Typically, a laser consists of two mirrors on either side of a gain medium - a material whose structural properties allow it to amplify light. A source of energy such as a flash tube or electrical discharge excites the atoms in the gain medium, releasing photons. Normally, these would shoot out in random directions, as in the broad beam of a flashlight, but a laser uses mirrors on either end of the gain medium to create a directed beam. As photons bounce back and forth between the mirrors, repeatedly passing through the gain medium, they stimulate other atoms to release photons of exactly the same wavelength, phase and direction. Eventually, a concentrated single-frequency beam of light erupts through one of the mirrors as laser light.
Artificial hippocampal system restores long-term memory, enhances cognition | KurzweilAI - 2 views
-
Theodore Berger and his team at the USC Viterbi School of Engineering's Department of Biomedical Engineering have developed a neural prosthesis for rats that is able to restore their ability to form long-term memories after they had been pharmacologically blocked. In a dramatic demonstration, Berger blocked the ability to rats to form long-term memories by using pharmacological agents to disrupt the neural circuitry that communicates between two subregions of the hippocampus, CA1 and CA3, which interact to create long-term memory, prior research has shown. The rats were unable to remember which lever to pull to gain a reward, or could only remember for 5-10 seconds, when previously they could remember for a long period of time. The researchers then developed an artificial hippocampal system that could duplicate the pattern of interaction between CA3-CA1 interactions. Long-term memory capability returned to the pharmacologically blocked rats when the team activated the electronic device programmed to duplicate the memory-encoding function. The researchers went on to show that if a prosthetic device and its associated electrodes were implanted in animals with a normal, functioning hippocampus, the device could actually strengthen the memory being generated internally in the brain and enhance the memory capability of normal rats. "These integrated experimental modeling studies show for the first time that with sufficient information about the neural coding of memories, a neural prosthesis capable of real-time identification and manipulation of the encoding process can restore and even enhance cognitive mnemonic processes," says the paper. Next steps, according to Berger and Deadwyler, will be attempts to duplicate the rat results in primates (monkeys), with the aim of eventually creating prostheses that might help human victims of Alzheimer's disease, stroke, or injury recover function. Ref.: "A Cortical Neural Prosthesis for Restoring and Enhancing
2011 Gulf of Mexico 'dead zone' could be biggest ever - 1 views
-
ScienceDaily (July 18, 2011) - Researchers from Texas A&M University have returned from a trip to examine the scope and size of this year's "dead zone" in the Gulf of Mexico and have measured it currently to be about 3,300 square miles, or roughly the size of Delaware and Rhode Island combined, but some researchers anticipate it becoming much larger.
Boys reach sexual maturity younger and younger: Phase between being physically but not ... - 0 views
-
ScienceDaily (Aug. 19, 2011) - Boys are maturing physically earlier than ever before. The age of sexual maturity has been decreasing by about 2.5 months each decade at least since the middle of the 18th century. Joshua Goldstein, director of the Max Planck Institute for Demographic Research in Rostock (MPIDR), has used mortality data to demonstrate this trend, which until now was difficult to decipher. What had already been established for girls now seems to also be true for boys: the time period during which young people are sexually mature but socially not yet considered adults is expanding.
« First
‹ Previous
141 - 160 of 321
Next ›
Last »
Showing 20▼ items per page