Confidence Wins over Smarts

Written by Science Knowledge on 1:04 AM

Speaking up counts more than competence in becoming a leader

When a group of people works to complete a task, a leader usually emerges. New research shows such leaders are not necessarily more intelligent than the other group members, but rather they simply speak up more often. Researchers at the University of California, Berkeley, gave groups of college students 45 minutes to lay the groundwork for a business and then asked the students to rate one another on intelligence, judgment and other traits. The students believed that the people who spoke more often were the smartest in each group—even when, during another group exercise involving math problems, they offered more incorrect answers than did others who were less talkative. Those who did not say much were judged as averagely intelligent and not so creative. A later look at the participants’ SAT scores revealed that, on average, the leaders had the same scores as the rest of the group. “The main reason dominant people took charge is they jumped in first and nobody questioned what they said,” says psychologist Cameron Anderson, who led the study. “Dominant people seem really good at things because they speak with so much confidence.”

Source of Information : Scientific American Mind September-October 2009

Abruptly Forgotten

Written by Science Knowledge on 12:00 AM

Certain memories die suddenly rather than fading away

When you go from bed to bathroom on a dark night, a quick flick of the lights will leave a lingering impression on your mind’s eye. For decades evidence suggested that such visual working memories—which, even in daylight, connect the dots to create a complete scene as the eyes dart around rapidly—fade gradually over the span of several seconds. But a clever new study reported in the journal Psychological Science finds that such memories actually stay sharp until they are suddenly lost.

Cognitive psychologists Weiwei Zhang and Stephen J. Luck, both at the University of California, Davis, tested subjects’ recall for the hues of colored squares flashed briefly on a screen up to 10 seconds earlier. Subjects marked their answer on a color wheel. If memories decay gradually, the guesses should have become increasingly imprecise as time wore on, evidenced by participants selecting yellow or red, for example, when the correct choice was orange. Instead subjects went straight from fairly accurate answers to random choices—no better than chance—indicating the memories were decaying all at once. According to Zhang and Luck’s mathematical analysis, most subjects’ memories went “poof” somewhere between four and 10 seconds after the stimulus.

Researchers say a sudden die-off is to be expected if working memories are stored in circuits that feed back on themselves. Luck says the system is like a laptop as compared with a flashlight. “The laptop is an active system that uses feedback circuits to limit how much power it draws,” he says. So whereas a flashlight dims when it runs low on juice, “the computer runs perfectly normally while the battery drains,” he says, “until suddenly the laptop shuts off.”


Source of Information : Scientific American Mind September-October 2009

Smile! It Could Make You Happier

Written by Science Knowledge on 12:53 AM

Making an emotional face—or suppressing one—influences your feelings

We smile because we are happy, and we frown because we are sad. But does the causal arrow point in the other direction, too? A spate of recent studies of botox recipients and others suggests that our emotions are reinforced—perhaps even driven—by their corresponding facial expressions.

Charles Darwin first posed the idea that emotional responses influence our feelings in 1872. “The free expression by outward signs of an emotion intensifies it,” he wrote. The esteemed 19thcentury psychologist William James went so far as to assert that if a person does not express an emotion, he has not felt it at all. Although few scientists would agree with such a statement today, there is evidence that emotions involve more than just the brain. The face, in particular, appears to play a big role.

This February psychologists at the University of Cardiff in Wales found that people whose ability to frown is compromised by cosmetic botox injections are happier, on average, than people who can frown. The researchers administered an anxiety and depression questionnaire to 25 females, half of whom had received frown-inhibiting botox injections. The botox recipients reported feeling happier and less anxious in general; more important, they did not report feeling any more attractive, which suggests that the emotional effects were not driven by a psychological boost that could come from the treatment’s cosmetic nature. “It would appear that the way we feel emotions isn’t just restricted to our brain—there are parts of our bodies that help and reinforce the feelings we’re having,” says Michael Lewis, a co-author of the study. “It’s like a feedback loop.” In a related study from March, scientists at the Technical University of Munich in Germany scanned botox recipients with fMRI machines while asking them to mimic angry faces. They found that the botox subjects had much lower activity in the brain circuits involved in emotional processing and responses—in the amygdala, hypothalamus and parts of the brain stem—as compared with controls who had not received treatment.

The concept works the opposite way, too—enhancing emotions rather than suppressing them. People who frown during an unpleasant procedure report feeling more pain than those who do not, according to a study published in May 2008 in the Journal of Pain. Researchers applied heat to the forearms of 29 participants, who were asked to either make unhappy, neutral or relaxed faces during the procedure. Those who exhibited negative expressions reported being in more pain than the other two groups. Lewis, who was not involved in that study, says he plans to study the effect that botox injections have on pain perception. “It’s possible that people may feel less pain if they’re unable to express it,” he says.

But we have all heard that it is bad to repress our feelings—so what happens if a person intentionally suppresses his or her negative emotions on an ongoing basis? Work by psychologist Judith Grob of the University of Groningen in the Netherlands suggests that this suppressed negativity may “leak” into other realms of a person’s life.

In a series of studies she performed for her Ph.D. thesis and has submitted for publication, she asked subjects to look at disgusting images while hiding their emotions or while holding pens in their mouths in such a way that prevented them from frowning. A third group could react as they pleased.

As expected, the subjects in both groups that did not express their emotions reported feeling less disgusted afterward than control subjects. Then she gave the subjects a series of cognitive tasks that included fill-in-the-blank exercises. She found that subjects who had repressed their emotions performed poorly on memory tasks and completed the word tasks to produce more negative words—they completed “gr_ss” as “gross” rather than “grass,” for instance—as compared with controls. “People who tend to do this regularly might start to see the world in a more negative light,” Grob says. “When the face doesn’t aid in expressing the emotion, the emotion seeks other channels to express itself through.”

No one yet knows why our facial expressions influence our emotions as they seem to. The associations in our mind between how we feel and how we react may be so strong that our expressions simply end up reinforcing our emotions—there may be no evolutionary reason for the connection. Even so, our faces do seem to communicate our states of mind not only to others but also to ourselves. “I smile, so I must be happy,” Grob says.


Source of Information : Scientific American Mind September-October 2009

Dancing with the Starlings

Written by Science Knowledge on 1:30 AM

Birds’ rhythmic abilities offer clues to the origins of dance

Researchers have long assumed that humans were the only animals that could dance—even our close primate relatives cannot keep a steady beat or be taught to move to a rhythm. But new evidence shows that birds can dance, revealing that the mysterious ability could be a by-product of vocal learning.

Aniruddh Patel of the Neurosciences Institute, Adena Schachner of Harvard University and their colleagues studied several birds, among them a cockatoo that dances to the Backstreet Boys’ “Everybody.” When Patel sped up or slowed down the song, the bird adjusted its moves to match the tempo, eliminating the possibility that it was in sync with the music by chance. Intrigued, Schachner and her colleagues started searching YouTube for videos of other dancing animals. They found 15 bopping species (14 parrot and one elephant) that also share an additional trait: the capability to imitate sounds. That correlation suggests our musical ability grew out of the vocal learning
system instead of being “a special-purpose ability,” Patel says. The findings could help advance research on movement disorders, he adds. Hearing music helps Parkinson’s patients to walk, for example. So far scientists do not understand the underlying mechanisms, but if bird brains share certain key circuits with humans, then scientists may find answers by studying them.

Source of Information : Scientific American Mind September-October 2009

Say Cheese

Written by Science Knowledge on 1:26 AM

Kids’ smiles predict their future marriage success

Pictures of grinning kids may reveal more than childhood happiness: a study from DePauw University shows that how intensely people smile in childhood photographs, as indicated by crow’s feet around the eyes, predicts their adult marriage success. According to the research, people whose smiles were weakest in snapshots from childhood through young adulthood were most likely to report being divorced in middle and old age. Among the weakest smilers in college photographs, one in four ended up divorcing, compared with one in 20 of the widest smilers. The same pattern held among even those pictured at an average age of 10.

The paper builds on a 2001 study by psychologists at the University of California, Berkeley, that tracked the well-being and marital satisfaction of women from college through their early 50s. That work found that coeds whose smiles were brightest in their senior yearbook photographs were most likely to be married by their late 20s, least likely to remain single into middle age, and happiest in their marriage; they also scored highest on measures of overall well-being (including psychological and physical difficulties, relationships with others and general self-satisfaction).

The scientists speculate that one’s tendency to grin—an example of what psychologists call “thin slices” of behavior that can belie personal traits—reflects his or her underlying emotional disposition. Positive emotionality influences how others respond to a person, perhaps making that individual more open and likely to seek out situations conducive to a lasting, happy marriage. But there could be a more cynical explanation, according to Matthew Hertenstein, a psychologist at DePauw who led the new study. “Maybe people who look happier in photos show a social face to others,” he says. “Those may be the same people who are likely to put up with partners because they don’t want to appear unhappy.”


Source of Information : Scientific American Mind September-October 2009

Memory Maintenance

Written by Science Knowledge on 1:53 AM

As recollections age, different brain areas take charge of the upkeep

The brain’s ability to learn and form memories of day-today facts and events depends on the hippocampus, a structure deep within the brain. But is the hippocampus still maintaining the memory of, say, the commencement address at your college graduation 20 years ago? The latest evidence suggests that as memories age, the hippocampus’s participation wanes.

In a 2006 study, neuroscientist Larry R.Squire of the University of California, San Diego, and the Veterans Affairs San Diego Healthcare System studied patients who had hippocampal damage. These individuals did not remember details of newsworthy events that occurred in the five to 10 years prior to their injuries, but they did recall older events.

Building on those results, Squire turned to healthy brains. His team questioned 15 people in their 50s and 60s about events in the news over the past 30 years while scanning the participants’ brains with functional MRI. To single out brain activity related to the date of the event, the researchers separately evaluated activity tied to learning and remembering the test questions. They also accounted for the richness of participants’ recollections of events, to make sure the degree to which someone was able to recall an event did not influence the data.

Squire’s team reported in January that activity in the hippocampus steadily declined as subjects remembered events that were up to 12 years old. With more remote memories, the structure’s activity leveled off. In contrast, areas in the frontal, temporal and parietal lobes displayed increasing activity for recalled events from those dozen years, then reached a plateau during older remembrances.

The biology behind how the brain makes and keeps memories is not fully understood, Squire notes, but it appears that, initially, a memory resides in the hippocampus and in areas the structure connects to in the neocortex, the outer part of the cerebral cortex. “A time comes when the cortical regions important to a memory are connected [to one another] heavily enough to form a stable representation,” Squire says. “Then the hippocampus isn’t needed to hold the whole thing together.”

Source of Information : Scientific American Mind September-October 2009


About Me

In its broadest sense, science (from the Latin scientia, meaning "knowledge") refers to any systematic knowledge or practice. In its more usual restricted sense, science refers to a system of acquiring knowledge based on scientific method, as well as to the organized body of knowledge gained through such research.

Fields of science are commonly classified along two major lines: natural sciences, which study natural phenomena (including biological life), and social sciences, which study human behavior and societies. These groupings are empirical sciences, which means the knowledge must be based on observable phenomena and capable of being experimented for its validity by other researchers working under the same conditions.


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