A tiny fish common in European streams may learn in a more sophisticated way than has ever been recorded among animals and which mimics human learning. In a study published in the journal Behavioral Ecology, scientists found that the nine-spined stickleback fish used the success and failures of their peers to gauge where they should seek food.
The fish were shown to display a type of learning known as “hill-climbing,” in which an entity continually looks for a better solution to a problem; in this case, one fish copied others that were more successful in finding food. Researchers caught 270 nine-spined sticklebacks in Leicester, England. The fish were organized into experimental groups. These fish groups then took turns as either free swimmers in a tank with worm-yielding feeders at the end, or as “learners” in a transparent, partitioned-off area of the specially designed tank. One of the two feeders released more worms than the other [Discovery News].
The first group of free-swimming fish quickly learned which feeder was full of worms, and were then put into the observers’ chamber. Next, researchers switched which feeder held the worms, and the fish in the observation tank watched the next fish group identify the new worm-filled feeder. After switching the two groups of fish again, the original group made a beeline for the feeder full of worms that their peers had fed from.
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Parents might know that sitting children in front of the television for hours at a time isn’t the best way to encourage intellectual growth. But a new study published in the Archives of Pediatrics and Adolescent Medicine shows that simply having the TV on in the background can stifle interaction between parent and child, decreasing the number of words spoken and possibly slowing the development of a baby’s language skills.
Scientists have long suspected that TV viewing can damage early development. In fact, the American Academy of Pediatrics recommends avoiding exposure to television before an infant is two years old, a period when important cognitive changes take place. “We’ve known that television exposure during infancy is associated with language delays and attentional problems, but so far it has remained unclear why,” said lead researcher Dimitri Christakis [LiveScience].
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Researchers have more evidence that takes aim at the old stereotype that boys are better at math than girls. Psychologist Janet Hyde had previously studied scores on standardized math tests in the United States, and found no difference in performance between girls and boys. Her new study expands the scope of the work by analyzing international data. She and her colleague analyzed studies from around the world on math performance along with gender inequality as measured by the World Economic Forum’s Gender Gap Index. This index measures the gap between men and women in economic opportunity, educational attainment and other socioeconomic factors [LiveScience].
They found that countries with poor gender equality, like India, had a larger gender gap in math, while in countries with excellent gender equality, like the Netherlands, girls performed as well as boys. If males really did have an innate advantage in math, the researchers note, that advantage should be obvious throughout all these cultures. Instead, the study suggests that cultural issues are the basis of the math gender gap.
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The Saturday Night Live character who famously recited the mantra: “I’m good enough, I’m smart enough, and doggone it, people like me” may have been setting a valuable example for schoolkids. A new study asked middle school students to do short, self-affirming writing exercises, and found that the simple task boosted the grades of some students for two years afterward. The students who benefited most were blacks who were doing poorly, the study found; the exercises made no difference for white students, or for black ones who were already doing well [The New York Times].
The result is exciting, lead researcher Geoffrey Cohen says, because it suggests that even modest interventions, when done early, can interrupt a downward achievement spiral. “Small changes to an individual’s psychological state can have surprisingly large effect over time if they alter the angle of people’s performance trajectory,” he said, adding that the early benefit is compounded over time [Reuters].
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Sleep may be a way to sweep out the brain and get it ready for a new day of building connections between neurons, according to two new studies of fruit flies. The studies support the controversial theory that sleep weakens or entirely dissolves some synapses, the connections between brain cells. “We assume that if this is happening, it is a major function, if not the most important function, of sleep” [Science News], says Chiara Cirelli, a coauthor of the first study, published in Science.
Pruning synapses may be a practical necessity to keep the brain from being overwhelmed, says Paul Shaw, coauthor of the second study (also published in Science). “There are a number of reasons why the brain can’t indefinitely add synapses – including the finite spatial constraints of the skull. We were able to track the creation of new synapses in fruit flies during learning experiences – and to show that sleep pushed that number back down” [Telegraph], he says.
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When people are given “expert” financial advice, the decision-making parts of the brain shut down, a small new study has found. Brain scans of 24 volunteers showed that claims of expertise were found to suppress activity in the neural circuit linked to decision-making [Telegraph]. “It’s almost as if the brain stops trying to make a decision on its own” [CNN], said lead researcher Gregory Berns.
In the study, college students connected to MRI scanners were asked to choose between taking a guaranteed payment and gambling for a higher payoff. Some made the decision on their own, while others were given written advice that they were told came from an economist who counsels the U.S. Federal Reserve. The advice was intentionally poor, and urged students to accept the guaranteed small payments rather than gamble with good odds for a much higher return. When thinking for themselves, students showed activity in their anterior cingulate cortex and dorsolateral prefrontal cortex — brain regions associated with making decisions and calculating probabilities. When given advice from [the economist], activity in those regions flat lined [Wired]. The students who received the advice tended to follow it.
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Brain scans can pick up the distinct pattern of brain waves that occur when a person’s attention lapses, and can therefore predict when the person is about to make a mistake, according to a small new study.
Using magnetoencephalography (MEG), researchers monitored the oscillations in brain activity for 14 test subjects. Each student was asked to take part in monotonous test in which a random number from one to nine flashed on a screen every two seconds, and they were asked to tap a button as soon as any number except five appeared. The test was so boring that even when a five showed up, the subjects spontaneously hit the button an average of 40% of the time [BBC News].
About a second before they committed the error, brain waves in two regions spiked: alpha wave activity in the occipital region was about 25 percent greater than usual, and in the sensorimotor cortex there was a corresponding increase in the brain’s mu wave activity.
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To figure out whether you’ll like the restaurant around the corner or that new guy in accounting or a vacation in Madrid, or just about anything else you’ve never personally experienced, try asking a stranger who has [Time]. That stranger is likely to predict, better than you can yourself, how much enjoyment you’ll get from that new experience (or the guy in accounting).
Previous research has shown that people tend to overestimate how disappointed or unhappy they will be after a perceived negative event, such as being denied a promotion, as well as how happy they will feel after positive events, like winning a prize. Building on that knowledge, psychology professor Daniel Gilbert conducted experiments in which he asked people to predict how much they’d enjoy a future event that they knew nothing about—except how much a total stranger had enjoyed it. Those people, it turns out, made extremely accurate predictions [WebMD].
In one experiment, women were asked to partake in “speed dating.” Subjects given reviews by women who had already “dated” participating men were able to gauge how well a date would go better than those who were only shown a picture and profile, and asked to come to their own conclusions.
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A controversial autism treatment has gotten a credibility boost. The first rigorously scientific study of hyperbaric oxygen treatment, in which autistic children breathe in extra oxygen inside a pressurized chamber, found that children who received the treatment showed improvement in social interactions, although researchers note that the small study didn’t examine whether the treatment had long-term effects.
Study leader Dan Rossignol says the use of hyperbaric therapy for autism has been gaining popularity in the US where parents can buy their own hyperbaric chamber if they have a spare $14-17,000 [BBC News]. Other parents take their children to clinics for treatments that usually cost between $120 and $150 per session, and which typically aren’t covered by insurance providers. Rossignol says he expects the findings to generate controversy, and notes that he too was initially very sceptical of the idea but was prompted to do more research after the treatment showed benefits for his two sons who have autism. “We’re certainly not talking about a cure, we’re talking about improvements in behaviour, improving certain functions and quality of life” [BBC News].
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Men who are older when they father children tend to have children who score slightly lower on IQ tests and other measures of cognitive function, according to a new study. That conclusion, which researchers called unexpected and startling, adds to a recent surge of evidence that, like women, men also have a biological clock. Older fathers have been linked to a range of health problems, including an increased risk of birth deformities, autism and neuropsychiatric conditions, such as schizophrenia and bipolar disorder…. Experts believe mutations in a man’s sperm, which build over time, may be a factor [BBC News].
However, lead researcher John McGrath says that the findings shouldn’t cause panic. “With respect to childhood intelligence, a vast array of factors is far more powerful than paternal age,” McGrath cautions. These factors include nutrition, health care and family income [Science News]. Researchers say that adjusting for socioeconomic factors like family income lessened the link between paternal age and children’s cognitive scores, but didn’t erase it. The average IQ of a child born to a 20-year-old father was six points higher than that of a child with a 50-year-old father, but adjustments reduced the difference to three points. Researchers say that gap is statistically significant, but is modest in practical terms [Science News].
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Toddlers who use gestures to convey more meanings at the age of 14 months have more extensive vocabularies when they enter school several years later, a new study has revealed. “Our findings contradict the folklore,” said Prof Susan Goldin-Meadow, co-author on the study. “Your grandma always told you – if you’re really articulate you shouldn’t have to use your hands at all” [BBC News]. Instead, there’s a clear link between gestures and language acquisition, Goldin-Meadow says.
The effect begins with the parents, researchers say–parents who gesture more when interacting with their toddlers produce the same behavior in their children. But unfortunately, the parental habit is distributed unevenly, researchers say, with wealthier, better-educated parents gesturing much more to their children. This may help explain why some children from low-income families fare less well in school. “When children enter school, there is a large socioeconomic gap in their vocabularies” [Reuters], says lead researcher Meredith Rowe. Encouraging lower income parents to gesture more to their children, Rowe says, might help erase that gap.
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To a gambler’s brain, a near miss provides almost the same high as a win, according to a new study that helps explain the allure of slot machines and the difficulty that some gamblers have in walking away. “The near-miss is quite a paradoxical event,” [researcher Luke] Clark says. Gamblers who almost win put “their head down in their hands — they can’t believe it. And then the next thing they do is place another bet” [Science News].
In the small study, published in Neuron [subscription required], researchers had 15 volunteers play a slot machine while their brain activity was recorded with fMRI scans. When the researchers compared the scans, they found that near misses drew more blood to reward regions such as the insula and the ventral striatum than full misses did [ScienceNOW Daily News]. These areas are also activated by rewards like chocolate and cocaine; when the near misses partially activated the so-called reward pathway, it released pleasant doses of the brain chemical dopamine.
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Honeybees have the ability to distinguish and remember visual quantities up to four, according to a new study. Researchers demonstrated that honeybees can match patterns containing the same number of icons, even when the icons are of mixed color and shape. This suggests that honeybees possess a basic number sense that was once thought to be exclusive to vertebrates. Researcher Shaowu Zhang says, “There has been a lot of evidence that vertebrates, such as pigeons, dolphins or monkeys, have some numerical competence but we never expected to find such abilities in insects. So far as these very basic skills go, there is probably no boundary between insects, animals and us” [Daily Mail]
To test the extent of the bees’ number sense, researchers set up a Y-shaped maze with a sweet treat at the end of one arm. In the training phase, bees entered the base of the maze through an entrance marked with either two or three dots. They had to remember this number when the maze forked into two paths— one marked with two dots, the other with three—in order to reach a sugar-water reward [Telegraph]. The 20 or so bees that were trained attained a success rate of 70 percent. Researchers then presented tougher challenges by increasing the number of dots. The bees could also distinguish between three and four dots, but were confused when even more dots were added.
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Capuchin monkeys not only have the capacity to use tools, they also know which tool is best for the job at hand, according to a new study. Researchers observed capuchin monkeys in the wild testing out different stones and consistently settling on the heaviest, sturdiest stone to crack open palm nuts. Although anecdotal reports existed before, the new study is the first to systematically document tool use in capuchin monkeys. Because capuchins last shared a common ancestor with humans approximately 35 million years ago, the team writes, the capacity for stone-tool use evolved earlier than thought [New Scientist].
Researchers studied eight wild capuchins living in a forested area of Brazil. In several different trials, researchers planted two or three different rocks, of varying hardness, size, and weight, near where the monkeys were feeding. The choices ranged from crumbly sandstone to tough quartzite, with some artificial stones that the monkeys would not normally encounter also thrown in the mix. Capuchins chose the most effective stone for cracking nuts more than 90 percent of the time in four conditions. That figure fell slightly to 85 percent when the monkeys selected from artificial stones of the same size and different weights [Science News].
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The most famous neuroscience patient and test subject died last week, and the researchers who worked with him say they’ll never forget the man who never remembered them. The patient known as H.M. lost the ability to form new memories after he had brain surgery at the age of 27, and studies of his behavior taught researchers basic lessons about how memory and learning work. “He was a very gracious man, very patient, always willing to try these tasks I would give him,” [said Brenda] Milner, a professor of cognitive neuroscience. “And yet every time I walked in the room, it was like we’d never met” [The New York Times].
Henry Gustav Molaison, a Hartford [Connecticut] native, existed in relative obscurity. But as “H.M.,” the name used to disguise his identity, Molaison gained an anonymous sort of fame, a man who had been studied by more than 100 researchers and became a staple of psychology class lectures…. “I’ve been lecturing about him and teaching about him for years and years, decades, and I’ve never known his name” [Hartford Courant], says psychiatrist David Glahn. Molaison died at a Connecticut nursing home on Tuesday at the age of 82, of respiratory failure.
Molaison began having seziures after a childhood bicycle accident, and by the age of 27 they were seriously interfering with his daily life. In 1953 surgeons removed two slices of his brain and cut into a region called the hippocampus–this stopped his seizures, but also gave Molaison a form of amnesia where he could remember events from before the surgery but couldn’t form any new long-term memories.
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