August 26th, 2007 - Open Knowledge — LiveJournal
Aug. 26th, 2007
08:31 pm - This is your brain on love
“…In an experiment published as a chapter in a 2006 book, “Evolutionary Cognitive Neuroscience,” Fisher found 17 people who were in relationships for an average of seven months. She knew they were in love from their answers to what researchers call the Passionate Love Scale. They all said they’d feel deep despair if their lover left, and they yearned to know all there was to know about the loved one.
She put these lovesick, enraptured people in an fMRI to see what areas of their brains got active when they saw a photograph of their beloved ones.
“We found some remarkable things,” she said. “We saw activity in the ventral tegmental area and other regions of the brain’s reward system associated with motivation, elation and focused attention.” It’s the same part of the brain that presumably is active when a smoker reaches for a cigarette or when gamblers think they’re going to win the lottery. No wonder it’s as hard to say no to the feeling of romantic arousal as it would be to say no to a windfall in the millions. The brain has seen what it wants, and it’s going to get it.
“At that point, you really wouldn’t notice if he had three heads,” Fisher says. “Or you’d notice, but you’d choose to overlook it.”
Other studies also suggest that the brain in the first throes of love is much like a brain on drugs.
Lucy Brown, professor of neuroscience at the Albert Einstein College of Medicine, has also taken fMRI images of people in the early days of a new love. In a study reported in the July 2005, Journal of Neurophysiology, she too found key activity in the ventral tegmental area. “That’s the area that’s also active when a cocaine addict gets an IV injection of cocaine,” Brown says. “It’s not a craving. It’s a high.”
You see someone, you click, and you’re euphoric. And in response, your ventral tegmental area uses chemical messengers such as dopamine, serotonin and oxytocin to send signals racing to a part of the brain called the nucleus accumbens with the good news, telling it to start craving.
“The other person becomes a goal in your life,” Brown says. He or she becomes a goal you might die without and would pack up and move across the country for. That one person begins to stand out as the one and only…”
08:38 pm - Festo Air Ray
“Air_ray, modelled on the manta ray, is a remote-controlled hybrid construction consisting of a helium-filled ballonet and a beating wing drive. Its light design makes it possible for it to “swim” in the sea of air, boosted by helium, in a similar way to the manta ray in water.
Propulsion is achieved by a beating wing drive. The servo drive-controlled wing, which can move up and down, utilises the Fin Ray Effect® and is based on alternate pulling and pushing flanks connected via frames. When pressure is exerted on one flank, the geometrical structure curves automatically against the direction of the influencing force. A servo drive pulls the two flanks alternately in the longitudinal direction, thus moving the wing up and down.”
08:40 pm - Lobes of Steel
“….Scientists have suspected for decades that exercise, particularly regular aerobic exercise, can affect the brain. But they could only speculate as to how. Now an expanding body of research shows that exercise can improve the performance of the brain by boosting memory and cognitive processing speed. Exercise can, in fact, create a stronger, faster brain.
This theory emerged from those mouse studies at the Salk Institute. After conducting maze tests, the neuroscientist Fred H. Gage and his colleagues examined brain samples from the mice. Conventional wisdom had long held that animal (and human) brains weren’t malleable: after a brief window early in life, the brain could no longer grow or renew itself. The supply of neurons — the brain cells that enable us to think — was believed to be fixed almost from birth. As the cells died through aging, mental function declined. The damage couldn’t be staved off or repaired.
Gage’s mice proved otherwise. Before being euthanized, the animals had been injected with a chemical compound that incorporates itself into actively dividing cells. During autopsy, those cells could be identified by using a dye. Gage and his team presumed they wouldn’t find such cells in the mice’s brain tissue, but to their astonishment, they did. Up until the point of death, the mice were creating fresh neurons. Their brains were regenerating themselves.
All of the mice showed this vivid proof of what’s known as “neurogenesis,” or the creation of new neurons. But the brains of the athletic mice in particular showed many more. These mice, the ones that scampered on running wheels, were producing two to three times as many new neurons as the mice that didn’t exercise.
But did neurogenesis also happen in the human brain? To find out, Gage and his colleagues had obtained brain tissue from deceased cancer patients who had donated their bodies to research. While still living, these people were injected with the same type of compound used on Gage’s mice. (Pathologists were hoping to learn more about how quickly the patients’ tumor cells were growing.) When Gage dyed their brain samples, he again saw new neurons. Like the mice, the humans showed evidence of neurogenesis.
This spring, neuroscientists at Columbia University in New York City published a study in which a group of men and women, ranging in age from 21 to 45, began working out for one hour four times a week. After 12 weeks, the test subjects, predictably, became more fit. Their VO2 max, the standard measure of how much oxygen a person takes in while exercising, rose significantly.
But something else happened as a result of all those workouts: blood flowed at a much higher volume to a part of the brain responsible for neurogenesis. Functional M.R.I.’s showed that a portion of each person’s hippocampus received almost twice the blood volume as it did before. Scientists suspect that the blood pumping into that part of the brain was helping to produce fresh neurons.
The hippocampus plays a large role in how mammals create and process memories; it also plays a role in cognition. If your hippocampus is damaged, you most likely have trouble learning facts and forming new memories. Age plays a factor, too. As you get older, your brain gets smaller, and one of the areas most prone to this shrinkage is the hippocampus. (This can start depressingly early, in your 30’s.) Many neurologists believe that the loss of neurons in the hippocampus may be a primary cause of the cognitive decay associated with aging. A number of studies have shown that people with Alzheimer’s and other forms of dementia tend to have smaller-than-normal hippocampi.
The Columbia study suggests that shrinkage to parts of the hippocampus can be slowed via exercise. The subjects showed significant improvements in memory, as measured by a word-recall test. Those with the biggest increases in VO2 max had the best scores of all.
“It’s reasonable to infer, though we’re not yet certain, that neurogenesis was happening in the people’s hippocampi,” says Scott A. Small, an associate professor of neurology at Columbia and the senior author of the study, “and that working out was driving the neurogenesis.”
08:43 pm - Go, Antigua, Go!
“…The dispute stretches back to 2003, when Mr. Mendel first persuaded officials in Antigua and Barbuda, a tiny nation in the Caribbean with a population of around 70,000, to instigate a trade complaint against the United States, claiming its ban against Americans gambling over the Internet violated Antigua and Barbuda’s rights as a member of the W.T.O.
Antigua is best known to Americans for its pristine beaches and tourist attractions like historic English Harbor. But the dozens of online casinos based there are vital to the island’s economy, serving as its second-largest employer.
More than a few people in Washington initially dismissed as absurd the idea that the trade organization could claim jurisdiction over something as basic as a country’s own policies toward gambling. Various states and the federal government, after all, have been deeply engaged for decades in where and when to allow the operation of casinos, Indian gambling halls, racetracks, lotteries and the like.
But a W.T.O. panel ruled against the United States in 2004, and its appellate body upheld that decision one year later. In March, the organization upheld that ruling for a second time and declared Washington out of compliance with its rules.
That has placed the United States in a quandary, said John H. Jackson, a professor at Georgetown University Law Center who specializes in international trade law.
Complying with the W.T.O. ruling, Professor Jackson said, would require Congress and the Bush administration either to reverse course and permit Americans to place bets online legally with offshore casinos or, equally unlikely, impose an across-the-board ban on all forms of Internet gambling — including the online purchase of lottery tickets, participation in Web-based pro sports fantasy leagues and off-track wagering on horse racing.
But not complying with the decision presents big problems of its own for Washington. That’s because Mr. Mendel, who is claiming $3.4 billion in damages on behalf of Antigua, has asked the trade organization to grant a rare form of compensation if the American government refuses to accept the ruling: permission for Antiguans to violate intellectual property laws by allowing them to distribute copies of American music, movie and software products, among others.
For the W.T.O. itself, the decision is equally fraught with peril. It cannot back down because that would undermine its credibility with the rest of the world. But if it actually carries out the penalties, it risks a political backlash in the United States, the most powerful force for free-flowing global trade and the W.T.O.’s biggest backer….”
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