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A study published Sept. 29 by Luis Populin, a professor of anatomy at the University of Wisconsin-Madison, shows that under specific conditions, a rhesus macaque monkey that normally would fail the "mark test" can still recognize itself in the mirror and perform actions that scientists would expect from animals that are self-aware.

A new study co-authored by MIT researchers documents the existence of collective intelligence among groups of people who cooperate well, showing that such intelligence extends beyond the cognitive abilities of the groups' individual members, and that the tendency to cooperate effectively is linked to the number of women in a group.

Cancer is a modern, man-made disease caused by environmental factors such as pollution and diet, a study by University of Manchester scientists has strongly

Scientists with the Lawrence Berkeley National Laboratory (Berkeley Lab) have designed an electrical link to living cells engineered to shuttle electrons across a cell's membrane to an external acceptor along a well-defined path. This direct channel could yield cells that can read and respond to electronic signals, electronics capable of self-replication and repair, or efficiently transfer sunlight into electricity.

The fruit fly has evolved a method for arranging the tiny, hair-like structures it uses to feel and hear the world that's so efficient a team of scientists in Israel and at Carnegie Mellon University says it could be used to more effectively deploy wireless sensor networks and other distributed computing applications.

The brain's visual neurons continually develop predictions of what they will perceive and then correct erroneous assumptions as they take in additional external information, according to new research done at Duke University.

MIT scientists have discovered that endothelial cells, which line the blood vessels, secrete molecules that suppress tumor growth and keep cancer cells from invading other tissues, a finding that could lead to a new way to treat cancer.

The Internet has become not only a tool for disseminating knowledge through scientific publications, but it also has the potential to shape scientific research through expanding the field of metaknowledge - the study of knowledge itself, according to an article published by University of Chicago researchers in the journal Science.

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.

Researchers at the University of Rochester have determined that when humans see the color red, their reactions become both faster and more forceful. The researchers measured the reactions of students in two experiments. In the first, 30 fourth-through-10th graders pinched and held open a metal clasp. Right before doing so, they read aloud their participant number written in either red or gray crayon. In the second experiment, 46 undergraduates squeezed a handgrip with their dominant hand as hard as possible when they read the word "squeeze" on a computer monitor. The word appeared on a red, blue, or gray background. In both scenarios, red significantly increased the force exerted, with participants in the red condition squeezing with greater maximum force than those in the gray or blue conditions, the researchers said. Ref.: Andrew J. Elliot, Henk Aarts, Perception of the color red enhances the force and velocity of motor output, Emotion, Vol 11(2), Apr 2011, 445-449

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

The hypothesis suggests that sexual reproduction via cross-fertilization keeps host populations one evolutionary step ahead of the parasites, which are frantically co-evolving to infect them. So both hosts and parasites are running (evolving) as fast as they can just to stay in the same place.

Fats in foods like potato chips and french fries make them nearly irresistible because they trigger natural marijuana-like chemicals in the body called endocannabinoids, researchers at the University of California, Irvine, have found. The researchers discovered that when rats tasted something fatty, cells in their upper gut started producing endocannabinoids, while sugars and proteins did not have this effect. How fats create, like, a buzz It starts on the tongue, where fats in food generate a signal that travels first to your brain, and then through a nerve bundle called the vagus to your intestines. There, the signal stimulates the production of endocannabinoids, which initiates a surge in cell signaling that prompts you to totally pig out - probably by initiating the release of digestive chemicals linked to hunger and satiety that compel us to eat more. And that leads to obesity, diabetes and cancer, the researchers said. But they suggest it might be possible to curb this process by obstructing endocannabinoid activity: for example, by using drugs that "clog" cannabinoid receptors. The trick: bypassing the brain to avoid creating anxiety and depression (which happens when endocannabinoid signaling is blocked in the brain). I'm guessing McDonald's won't be adding that drug to their fries. Ref.: Daniele Piomelli, et al., An endocannabinoid signal in the gut controls dietary fat intake, PNAS, 2011; in press

An immune-suppressing drug called rapamycin could possibly treat Hutchinson-Gilford progeria syndrome (HGPS), a rare genetic disease that causes premature aging, and advance biological understanding of the normal aging process, according to researchers from the National Human Genome Research Institute (NHGRI) at the National Institutes of Health, the University of Maryland and Massachusetts General Hospital. Progeria is a genetic disorder characterized by dramatic premature aging. "Progerin that causes progeria also accumulates, although in very small amounts, in normal aging," said Dimitri Krainc, M.D., Ph.D., associate professor of neurology at Harvard Medical School. "However, if rapamycin proves to have beneficial effects in lifespan in humans it is safe to assume that it will not be just because it may clear progerin from cells, but also because it clears other toxic products that accumulate during aging." Ref.: Francis S. Collins, et al., Rapamycin Reverses Cellular Phenotypes and Enhances Mutant Protein Clearance in Hutchinson-Gilford Progeria Syndrome Cells, Science, 2011; [DOI: 10.1126/scitranslmed.3002346]

Listen up, Facebook and Twitter groupies: how easily can social pressure affect your memory? Very easily, researchers at the Weizmann Institute and University College London have proved, and they think they even know what part of the brain is responsible. The participants conformed to the group on these "planted" responses, giving incorrect answers nearly 70% of the time. Volunteers watched a documentary film in small groups. Three days later, they returned to the lab individually to take a memory test, answering questions about the film. They were also asked how confident they were in their answers. They were later invited back to the lab to retake the test. This time, the subjects were also given supposed answers of the others in their film-viewing group (along with social-media-style photos) while being scanned in a functional MRI (fMRI) that revealed their brain activity. Is most of what you know false? Planted among these were false answers to questions the volunteers had previously answered correctly and confidently. The participants conformed to the group on these "planted" responses, giving incorrect answers nearly 70% of the time. To determine if their memory of the film had actually undergone a change, the researchers invited the subjects back to the lab later to take the memory test once again, telling them that the answers they had previously been fed were not those of their fellow film watchers, but random computer generations. Some of the responses reverted back to the original, correct ones, but get this: despite finding out the scientists messed with their minds, close to half of their responses remained erroneous, implying that the subjects were relying on false memories implanted in the earlier session. An analysis of the fMRI data showed a strong co-activation and connectivity between two brain areas: the hippocampus and the amygdala. Social reinforcement could act on the amygdala to persuade our brains to replace a strong memory wi

Scientists at the McEwen Centre for Regenerative Medicine and the Ontario Cancer Institute have isolated a human blood stem cell in its purest form: as a single stem cell capable of regenerating the entire blood system. "This discovery means we now have an increasingly detailed road map of the human blood development system, including the much sought after stem cell," says principal investigator John Dick, who holds a Canada Research Chair in Stem Cell Biology and is a Senior Scientist at the McEwen Centre for Regenerative Medicine and the Ontario Cancer Institute, University Health Network (UHN). "We have isolated a single cell that makes all arms of the blood system, which is key to maximizing the potential power of stem cells for use in more clinical applications. Stem cells are so rare that this is a little like finding a needle in a haystack," says Dr. Dick. Ref.: John E. Dick, Isolation of Single Human Hematopoietic Stem Cells Capable of Long-Term Multilineage Engraftment, Science, July 2011: Vol. 333 no. 6039 pp. 218-221 [DOI: 10.1126/science.1201219]

"Researchers at Ohio State University have demonstrated the first plastic computer memory device that utilizes the spin of electrons to read and write data. An alternative to traditional microelectronics, the "spintronics" device could store more data in less space, process data faster, and consume less power."

Building on a tool that they developed in yeast four years ago, researchers at the Johns Hopkins University School of Medicine scanned the human genome and discovered what they believe is the reason people have such a variety of physical traits and disease risks.