You may remember more than your conscious brain knows, according to a nifty new study that will soon be published in the journal Neuron. Researchers gave college students memory tests while closely monitoring both their eye movements and their brain activity, and found that certain patterns revealed that a student was retrieving the memory of the right answer–although his conscious brain often never got it.
In the experiment, researchers presented a long sequence of pictures of faces paired with an outdoor scene, and finally showed the subject one landscape photo along with three faces, asking him to pick out the face that had originally be paired with the landscape. Immediately, activity in the brain region called the hippocampus increased, followed 500 to 750 milliseconds later by eye movements directed toward one of the three faces. When the hippocampus was more active, the eyes lingered on the correct face. Less hippocampus activity occurred when the eyes dwelled on an incorrect face…. The results suggest that eye movements can reveal unconscious memories activated in the hippocampus [Science News]. This pattern stayed the same regardless of whether the subject ultimately settled on the right answer.
Kids suffering from attention deficit hyperactivity disorder (ADHD) may have altered brain chemistry that prevents them from experiencing motivation and rewards like other people, according to a new study published in the Journal of the American Medical Association. Lead researcher Nora Volkow suggests that faulty transmission of the brain chemical dopamine may be to blame for the difficulty people with ADHD experience trying to finish tasks that have no immediate payoff — the difference between doing homework, for instance, and playing a video game [CBC News].
The researchers used PET brain scans to determine how the brains of people with and without ADHD handled the neurotransmitter dopamine, a versatile chemical that is involved in regulating mood, attention, and learning. In particular they measured levels of two proteins – dopamine receptors and transporters – without which dopamine cannot function effectively to influence mood. ADHD patients had lower levels of both proteins in two areas of the brain known as the nucleus accumbens and midbrain. Both form part of the limbic system, responsible for the emotions, and sensations such as motivation and reward [BBC News].
It may not come as much of a surprise to dog-owners, but it seems that dogs and babies share similar logical abilities, as shown by a study published in Science.
Experimenters started out with a classic logic experiment, which goes like this: researchers hide a toy in location “A” multiple times while looking at a 10-month-old baby and talking to him (”Look, I have this nice ball!”). When asked to find the toy, the baby always goes to location “A.” The experimenter then hides the toy at location “B,” again while interacting with the baby. But this time, when asked to find the toy, the baby continues to search for it at location “A.” The findings hold, even when a team changes experimenters midtest. Researchers believe that infants make this error because they believe the adults have taught them something fundamental about the world (i.e., “Your toy will always be at location ‘A’”) [ScienceNow].
If you’re trying to get people to work together, carrots may prove more useful than sticks–that is, rewarding cooperation might motivate people more than punishing them, according to a study published in Science.
Test subjects played the “public goods game,” in which they have to decide whether or not to donate money to the group’s pot. The pot is multiplied and redistributed equally, regardless of who contributes and who doesn’t. When people play a pure version of the game, the temptation to freeload – reap the rewards without contributing anything – often leads to rapidly disintegrating cooperation [New Scientist]. But researchers found that when players were given the choice to either reward their fellow players for good behavior, or punish them for failing to donate, rewarding others yielded a larger payoff for the group as a whole. Groups that could reward each other earned much higher payoffs than those that could only punish, or those that could do neither [ScienceBlogs].
Pigeons alert their flockmates to impending danger not through vocalization, but by making a whistling sound with their wings as they take off in response to a threat, according to a study published in the journal Proceedings of the Royal Society B. Researchers say other birds may also have co-opted the basic mechanical sounds of flight for communication purposes.
Biologists were curious about how all the pigeons in a huge flock knew to launch themselves into the air at the same moment. Because the birds don’t use vocal calls to alert their peers, scientists hypothesized they convey the message using their wings. Researchers first recorded the sounds made by crested pigeons flying happily around a feeder, then sent in a decoy of a hawk, and recorded their flight from the faux predator. When the researchers later played the sound back for a flock of birds, they didn’t so much as twitch at the normal recording. But the rapid clap-clap-clap of the alarmed bird sent them fleeing. Similarly, when the volume or speed of the recording was manipulated, birds only reacted to emergency wing whistles [Discovery News]. Although it’s not yet known exactly how the birds make these sounds, the study’s results could do more than increase our understanding of bird communication. They could also help repel the pesky birds from places where they are annoying or even harmful, like public parks and airports.
Meat may be tasty, but many people object to way that chickens, cows, and other animals are treated at so-called “factory farms,” which produce massive amounts of edible flesh. So could animals that have been genetically engineered to not feel pain (or at least not be bothered by the sensation) offer a solution to an ethical dilemma posed by these meat factories?
That’s what one philosopher asked in a paper published in the journal Neuroethics, concluding that we have an ethical duty to consider the option. “If we can’t do away with factory farming, we should at least take steps to minimise the amount of suffering that is caused” [New Scientist] by practices such as de-beaking chickens without anesthesia, says author Adam Shriver. But because pain serves as an important warning sign, these so-called “pain-free” animals would still be able to sense pain–they just wouldn’t be bothered by it. Researchers seek ways to eliminate the suffering caused by pain without tampering with the physical sensation [New Scientist].
As anyone who has a favorite (and least-favorite) musical artist knows, music can affect our moods. Now it seems it can do the same for cotton-top tamarin monkeys, but only when the music is composed specifically for them, according to a study published in the journal Biology Letters.
Except for one anomaly (they liked Metallica), the monkeys didn’t respond to samples of human music–but the tamarins did respond to cello music that was reminiscent of their natural calls. Cellist and composer David Teie studied recordings of both happy and upset tamarins, and used them as the bases for two different kinds of monkey music. “Basically I took those elements and patterned them the way we do normally with music,” he says. “You repeat them, take them up a [musical] third — you know, using the same kind of compositional techniques we use in human music.” He played the compositions on his cello and then electronically boosted them up three octaves, to a pitch that matched the monkeys’ voices [NPR].
Go ahead, let your teenagers play another few minutes of Tetris, that simple-yet-addictive puzzle game; it may well be good for their brain. Researchers have new evidence that playing Tetris makes a developing brain more efficient and thicker in certain regions.
The small study was conducted by neuroscientist Richard Haier, who was one of the first neuroscientists to explore the effects of video games on the brain. Back in 1992, Haier used brain scans to discover that some parts of the brain actually used less glucose as the players became more skilled at the game. The “Tetris effect” illustrated how video-game training could make brains work more efficiently – an idea that eventually led to a whole host of brain-training games [MSNBC]. For the new study, Haier updated his work by using newer, more sophisticated brain scanning technology to look for changes in the brains of adolescent girls after three months of Tetris playing. Adolescent girls were chosen because their brains were still developing, and because they were presumed to have less experience with video games than boys.
Male Brazilian free-tailed bats sing intricate songs to attract females and deter other males using a set syllabic order and syntax, according to a study published in the journal PLoS One. The bats can even add their own creative touches to the croonings.
By examining 400 songs produced by 33 free-tailed bats, researchers found that all the bats produce songs with a common hierarchical structure. “All are constructed from the same four types of syllables and all syllables are combined in the same way to form three types of phrases,” says [lead author Kirsten] Bohn. These phrases can be either chirps, trills or buzzes [BBC News], and the complexity of the songs rival those only of birds and whales, leaving those produced by mice in the dust. The bats may vary their songs to appeal more to females or to convey different sentiments. “Within the broad rules, the bats are quite versatile” [BBC News], Bohn says.
During both work hours and leisure time, a growing number of people have become extravagant multitaskers, flitting between Web browsing, texting, emailing, and maybe even throwing in some old-fashioned television or print media for good measure. But a surprising new study has found that those who multitask the most are far worse at it than those people who focus on fewer tasks simultaneously. Says study coauthor Clifford Nass: “The huge finding is, the more media people use the worse they are at using any media. We were totally shocked” [AP].
The researchers compared high- and low-multitaskers on a variety of psychological tests, according to the study published in the Proceedings of the National Academy of Sciences. They found that the high-multitaskers were worse at ignoring irrelevant information, worse at organizing information, and took more time to switch between tasks. That final finding particularly surprised the researchers, considering the need to switch from one thing to another in multitasking. “They couldn’t help thinking about the task they weren’t doing,” lead author Eyal Ophir said [AP].
In the first experiment linking cognitive ability to reproductive success, researchers found that the male bowerbirds with the best problem-solving capabilities also mated the most often, according to a study published in the journal Animal Behaviour.
The Australian bowerbird is known for its elaborate courtship behavior. During breeding season, males build a special platform, or bower, on the forest floor to lure females, and they decorate it with rare objects such as blue feathers and shiny bits of glass. They accompany this with varied vocalizations, hopping, and tail-bobbing [ScienceNOW Daily News]. To evaluate which males had the best problem-solving abilities, scientists placed a red object in the birds’ bowers–a color the birds disdain. In one experiment, three red objects were placed in the bower and covered by clear plastic that the bird had to take off in order to remove the noxious items. In the next, the red object was securely nailed to the nest, so the only way to make it less visible was to cover it with leaves and twigs.
It’s a movie cliche: the moment when the lost traveler intersects a set of footprints, only to realize that the prints where made by his very own boot soles. The hero then realizes, with plunging heart, that he’s been walking in circles while trying to walk a straight course through the featureless expanse. Now a small study has shown that the cliche is true. Without the sun, a compass or a landmark, people trying to follow a straight course through a forest or a desert ended up back where they started [HealthDay News].
In the first experiment, six participants tried to follow a straight course through a forest in Germany, in an area where the land is flat and the trees quickly begin to look alike. The two subjects who walked on a sunny day stayed on a fairly straight course (as tracked by a GPS device), except for the first 15 minutes when the sun was behind the clouds. But the four who walked on an overcast day repeatedly traveled in circles, sometimes crossing their own paths after only 10 minutes. Says lead researcher Jan Souman: “They didn’t really believe when we showed them afterwards…. I think that’s certainly a point to take away, people may feel very confident about the direction where they’re going but it’s not certain” [ABC News].
Researchers have found a way to reduce the ill-effects of heroin addiction and to generally keep the addicts out of trouble, but there’s a catch: The solution is to give the addicts injections of a pure form of pharmaceutical heroin twice a day. In a fascinating new study, Canadian researchers found that addicts who received the prescription heroin were more likely to stay in treatment than those given methadone, the commonly prescribed opioid that manages heroin cravings without providing the high. Experts say lengthy treatment is often needed to treat other diseases as well as provide counseling to reverse criminal behavior and otherwise stabilize addicts’ lives and improve the chances that they will stop using heroin [The Wall Street Journal].
The study enrolled 226 heroin addicts who had been using the drug for at least five years, and who had failed to stick with a methadone-treatment program at least once. Half the subjects came to the clinic to receive shots of diacetylmorphine—pure heroin—while the other half received standard methadone treatment. After one year, 88% of those in the diacetylmorphine group were still in treatment, compared with 54% in the methadone group [Los Angeles Times]. The test subjects who received heroin were also more likely to reduce their criminal behavior and their drug use outside the clinic, according to the study published in the New England Journal of Medicine.
In the hopes of combating rising suicide and mental illness rates, the U.S. Army is implementing a mental stress training course for all 1.1 million members of the National Guard, reservists, and active-duty soldiers.
The training, the first of its kind in the military, is meant to improve performance in combat and head off the mental health problems, including depression, post-traumatic stress disorder and suicide, that plague about one-fifth of troops returning from Afghanistan and Iraq [The New York Times]. The program will be taught by Army sergeants in classes that generally last about an hour-and-a-half, and will begin in October at two bases before spreading to all service members. The training will also be available for family members and civilian employees.
Scientists seem to have finally put to rest a longstanding debate over itchiness: Is the urge to itch a sensation that is simply another interpretation of pain, or a separate feeling altogether? It turns out the two stem from different cells and neural pathways, according to a new study in Science.
To find out whether pain and itchiness are separate sensations, scientists injected mice with a neurotoxin. This toxin homed in on and killed cells that contained active versions of GRPR, a gene that is involved in the sensation of itchiness. (The same research group discovered this itch gene in 2007.) Afterward, the mice could no longer respond to any itchy stimuli. They didn’t flinch. They made no effort to scratch. But they did respond to pain just like other mice do [TIME], showing that the gene needed to be active to transmit itchiness, but not pain. It’s just one study, but it provides strong evidence that itchiness and pain are processed by separate neural pathways.
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You may remember more than your conscious brain knows, according to a nifty new study that will soon be published in the journal Neuron. Researchers gave college students memory tests while closely monitoring both their eye movements and their brain activity, and found that certain patterns revealed that a student was retrieving the memory of the right answer–although his conscious brain often never got it.
Kids suffering from attention deficit hyperactivity disorder (
It may not come as much of a surprise to dog-owners, but it seems that dogs and babies share similar logical abilities, as shown by a 
If you’re trying to get people to work together, carrots may prove more useful than sticks–that is, rewarding cooperation might motivate people more than punishing them, according to a 
Meat may be tasty, but many people object to way that chickens, cows, and other animals are treated at so-called “factory farms,” which produce massive amounts of edible flesh. So could animals that have been genetically engineered to not feel pain (or at least not be bothered by the sensation) offer a solution to an ethical dilemma posed by these meat factories?
As anyone who has a favorite (and least-favorite) musical artist knows, music can affect our moods. Now it seems it can do the same for cotton-top tamarin 
Go ahead, let your teenagers play another few minutes of Tetris, that simple-yet-addictive puzzle game; it may well be good for their brain. Researchers have new evidence that playing Tetris makes a developing brain more efficient and thicker in certain regions.
During both work hours and leisure time, a growing number of people have become extravagant multitaskers, flitting between Web browsing, texting, emailing, and maybe even throwing in some old-fashioned television or print media for good measure. But a surprising new study has found that those who multitask the most are far worse at it than those people who focus on fewer tasks simultaneously. Says study coauthor Clifford Nass: “The huge finding is, the more media people use the worse they are at using any media. We were totally shocked” [
In the first experiment linking 
It’s a movie cliche: the moment when the lost traveler intersects a set of footprints, only to realize that the prints where made by his very own boot soles. The hero then realizes, with plunging heart, that he’s been walking in circles while trying to walk a straight course through the featureless expanse. Now a small study has shown that the cliche is true. 
Researchers have found a way to reduce the ill-effects of heroin 
In the hopes of combating rising 
Scientists seem to have finally put to rest a longstanding debate over itchiness: Is the urge to itch a 
