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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In a new experiment, researchers didn’t have to ask their test subjects whether they’d prefer coffee or tea; instead, they just read their minds. With a nifty bit of technical wizardry, researchers beamed near-infrared light at the volunteers’ foreheads while asking them to mentally decide which of two beverages they liked better. By examining how the light was absorbed by the volunteers’ brain tissue, researchers were able to predict a person’s preference with 80 percent accuracy.
Lead researcher Tom Chau says he hopes a similar device can one day help people with severe cerebral palsy or neuromuscular conditions that keep them paralyzed in unresponsive bodies. “Basically their mind is alert,” he said. “This is kind of the compelling argument behind the work, that these individuals are cognitively capable – they’re aware of their surroundings, they understand what’s going on – but they have no means of communicating their intentions or preferences to the outside world” [Canadian Press].
Coauthor Sheena Luu adds that the device could use simple preferences to build up to larger decisions and thoughts. “If we limit the context – limit the question and available answers, as we have with predicting preference – then mind-reading becomes possible” [The Register], she says.
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The global economic crisis has everybody looking for scapegoats–and now we may have a couple, in the form of a pair of genes that influence people’s desire to take financial risks. The two genes regulate dopamine, the brain chemical associated with reward and risk-taking, and serotonin, the chemical linked to mood and anxiety. In a new study, researchers found that people with the “high-risk” version of the dopamine gene tended to invest in risky but potentially lucrative propositions, while those with the “high anxiety” version of serotonin managed their money more carefully [Reuters].
While an experiment showed a clear correlation between the genes and risk-taking behavior, study coauthor Camelia Kuhnen says the results don’t suggest that all bankers should get their DNA tested. “I wouldn’t want to oversell this as a screening device to find good traders…. Even if I have a gene that predisposes me to taking a lot of financial risk, I could go through a stock market crash that will make me less risk-taking” [Scientific American], says Kuhnen.
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New research shows that even random guesses can sometimes be educated. Published in the latest Nature Neuroscience, a study by neuroscientists Ken Paller and Joel Voss has shown that choices we think of as instinctive may in fact be based on memories that can’t be consciously accessed [Telegraph].
Participants were given a special recognition test in which their memories of kaleidoscopic images were evaluated for accuracy. The subjects were distracted while viewing half of the images and paid full attention to the other half. When they were asked whether they’d seen particular images before, they were also asked if they consciously knew the correct answer or were taking a wild guess.
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When you need to brainstorm ideas for a big project, get yourself to a room that’s painted blue. But when it’s time to proofread the final product, find a red room. Those are the implications of a fascinating new study that measured the effect that colors have on cognition. Researchers found that red can make people’s work more accurate, and blue can make people more creative [The New York Times]. Since people associate red with danger, it primes them to proceed with more caution and diligence, Zhu reasons, while blue’s oceanic connotations put them in a more adventurous mood.
Researcher Juliet Zhu decided to tackle the topic because previous studies had come up with inconsistent findings. Some studies had found that red enhances cognition, for example, while other studies suggest the opposite. Zhu suspected this might be because the work didn’t pay enough attention to which types of cognition were being affected. Red might enhance performance on some tasks, she reasoned, while impairing performance on others [ScienceNOW Daily News].
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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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A small study suggests that men are better able to resist food cravings than women, which researchers say could partially explain why more women than men are obese, and why women are more prone to overeating when they’re under emotional stress. In a new brain-scan study, researchers flashed tasty food in front of men and women who hadn’t eaten anything in at least 17 hours. Both were told to fight their hunger, but only men showed a drop in activity in brain regions involved in emotion and motivation [CNN]. However, some researchers say that it’s risky to generalize based on a study with just 23 test subjects.
In the study, which will be published in Proceedings of the National Academy of Sciences, researchers engaged their volunteers in a somewhat torturous experiment. They first surveyed the volunteers about their favorite foods: Did they favor pizza, chocolate cake, burgers, or fried chicken? Then they were asked to fast overnight. When they returned to the lab the next day, the subjects got PET brain scans while being subjected to a barrage of craving-inducing stimuli. They looked at pictures of their favorite food, smelled its aroma wafting in from the next room, and even tasted it with cotton swabs placed on their tongues.
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Men who want to know if they’d make it as day traders on Wall Street just have to look down at the fingers, according to a new study. The longer their ring fingers are in relation to their pointer fingers, the more likely they are to have what it takes to make millions on the trading floor. Previous research has found that the digit ratio reflects how much testosterone an unborn baby was exposed to in the womb. Those exposed to high levels of the hormone are more sensitive as adults to testosterone that creates feelings of confidence and encourages risk-taking, said study author John Coates [Bloomberg].
Coates has previously shown that traders who register the highest levels of testosterone in the morning make the most money through the course of the day, and this new study adds to the earlier work by suggesting that their advantage may have been innate, not learned. Although it may come as no surprise that testosterone could be a big player in the mano-a-mano world of Wall Street, the research offers the best evidence yet of the hormone’s role in determining which would-be Masters of the Universe will thrive. It also supports the growing recognition that biology plays a role in complex human behaviors, and that financial choices in particular are often less rational than economists appreciated [Washington Post].
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In a new study, most people willingly pulled a lever to deliver pain to others when instructed to do so, showing that little has changed in the near half-century since psychologist Stanley Milgram’s famous electric shock experiment. Milgram’s experiment revealed our propensity to do harm when encouraged by authority, a topic of great interest in the post-World War II years. A new iteration of the experiment (with added precautions) revealed that seven out of ten people will give painful electric shocks to another person as part of what they are told is a scientific investigation. “What we found is validation of the same argument—if you put people into certain situations, they will act in surprising, and maybe often even disturbing, ways,” [Reuters] says researcher Jerry Burger.
In the 1961 experiment, Yale University professor Milgram asked volunteers to deliver increasingly strong electric “shocks” to other people, who appeared to be test subjects but were really actors, if they answered certain questions incorrectly. Milgram found that, after hearing an actor cry out in pain at 150 volts, 82.5 percent of participants continued administering shocks, most to the maximum 450 volts [Reuters]. The results, now a fixture in psychology textbooks, suggested that people’s moral attitudes can be suppressed when they’re put in a situation of obedience. Although no actual shocks were delivered and the sounds of agony came from a tape-recording, many of the volunteers suffered stress from the task and replication of the experiments was deemed unethical.
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When a juror first makes a decision on the guilt of a defendant and then hands down a sentence, two entirely different regions of the brain are involved, a new brain imaging study has shown—and neither is as rational as we might want to believe. Researchers using functional MRI scans found that a brain in the process of making a decision about the guilt of another person looks a lot like the brain of a person deciding whether they themselves have been wronged; what’s more, decisions about punishment are linked to brain regions that process emotions. “Our judicial system based on third-party punishment is usually seen as cold and detached as opposed to … punishment by the victim of a crime,” [study coauthor René] Marois says. The new study shows that emotions play a part in impartial judgment too [Science News].
Judgments of the culpability of another person were linked to activity in the right dorsolateral prefrontal cortexes, researchers found; this region has previously been implicated in decisions of morality and fairness, as well as other functions unrelated to the law. When another team temporarily blocked [activity in this region] with a magnet, participants playing a financial game that tests trust failed to punish unfair offers. No-one expected that almost the same cognitive machinery kicks in when impartially making a decision about cheating and when you yourself are cheated [New Scientist], says study coauthor Owen Jones.
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It’s not just we humans who value consensus: A new study has shown that stickleback fish make better decisions when acting as a group than they do as individuals. Researchers set up a clever experiment in which the fish had to choose which leader to follow in the quest for food, giving them an option between a “good” choice and a “bad” choice. Based on earlier experiments, the study’s researchers had a pretty good idea about … stickleback preferences. Fat, evenly colored fish are regarded as healthy and strong, while scrawny fish mottled with black spots may be considered diseased. Coauthor Ashley Ward … says of these sticklebacks, “Fish like large leaders, well-fed leaders and unparasitized leaders” [Science News].
Researchers made a stickleback replica that looked healthy and fat as well as one that appeared bony and mottled, and put both into the fish tank. When shown the fish replicas, the other sticklebacks in the tank would approach and follow one of the two replicas, which were moved around by remote control. Following a certain fish would be their version of casting a ballot…. When just one fish chose its leader, the fish would make the right choice, picking the healthiest leader about 55 percent of the time. That number went up to 80 percent with the eight-fish electorate [LiveScience].
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People who feel that they lack control while participating in lab experiments are more likely to see patterns where none exist, researchers say, in a finding that helps explain persistent beliefs in superstitions and conspiracy theories. In a new study, researchers manipulated volunteers’ perception of control and then watched the insecure subjects find connections where none existed in an apparent attempt to restore a sense of order to the world.
In one experiment, researchers gave half the volunteers a feeling of powerlessness and confusion by randomly scoring them right and wrong (and mostly wrong) on a series of questions. Then the volunteers had to find patterns. In one task, they were asked to find faint images in grainy patterns of dots. Half of the pictures had images and the others were random dots. While people in both groups correctly spotted the images, the group that felt they lacked control from a previous part of the experiment also “saw” images in 43 percent of pictures that were not there [Reuters].
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Teenage boys with behavior problems may be able to blame their brain chemistry, according to a new study. Psychologists studied boys with a history of antisocial behavior and measured their levels of the hormone cortisol, which usually surges during stressful situations, causing people to focus and behave more cautiously. They found that the troubled boys didn’t have the normal cortisol spike when they were put under stress, suggesting that they weren’t getting a chemical signal to regulate their emotions and actions.
Researchers say the findings suggest that some bad behavior should be considered a form of mental illness. “Most research has looked at social factors like peer groups, family life and socioeconomic factors,” said [lead researcher] Graeme Fairchild…. “These findings basically indicate that antisocial behavior is probably more biologically based than many people recognize and is similar to conditions like depression and anxiety” [Reuters].
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In a finding that has particular relevance right now, as the American public looks for scapegoats for the current financial crisis, a new study has found that men with higher levels of testosterone are inclined to make riskier financial decisions. Just how much riskier? Those with 33 percent more testosterone than average men invested 10 percent more of their dough. The findings are based on saliva samples from 98 male Harvard students taken before they played an investment game with $250 in real money [Scientific American].
Researchers say they didn’t outright prove that it was Wall Street men’s hormones that got us into this mess, but that the evidence is strongly suggestive. “Although our findings do not address causality, we believe that testosterone may influence how individuals make risky financial decisions,” said researcher Coren Apicella…. A recent study also showed that stock market traders made more money on days when their testosterone levels were highest [LiveScience].
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Ever wondered what causes the spate of wild bidding in the last few minutes of an Ebay auction? Scientists say they now have answer: The irrational behavior is caused by people’s fear of losing, not their desire to win. While economists have recognized the concept of “loss aversion” for some time, a new set of experiments used brain scans and lab experiments to show how strongly the phenomenon plays out in auctions, and how it’s tied to overbidding.
In the first experiment, test subjects participated in either a lottery or an auction. During the games, scientists watched the responses of the subjects’ striata—the brain’s reward center—using functional magnetic resonance imaging (fMRI). The elation of winning was the same in both games, but the agony of defeat was crushing for losers of the auction. After auction, brain activity in the loser’s reward centers decreased substantially. But it hardly blipped when the person lost a lottery [Ars Technica]. What’s more, auction losers who had the steepest declines in striata activity were more likely to have overbid during the auction.
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