Wednesday, March 10, 2010

OTHERS MAY KNOW US BETTER THAN WE KNOW OURSELVES

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Since at least the days of Socrates, humans have been advised to “know thyself.” And through all the years, many, including many personality and social psychologists, have believed the individual is the best judge of his or her own personality.

Now a psychologist at Washington University in St. Louis has shown that we are not the know-it-alls that we think we are.

Simine Vazire, Ph.D., Washington University assistant professor of psychology, has found that the individual is more accurate in assessing one’s own internal, or neurotic traits, such as anxiety, while friends are better barometers of intellect-related traits, such as intelligence and creativity, and even strangers are equally adept as our friends and ourselves at spotting the extrovert in us all, a psychology domain known as “extroversion.”

“I think that it’s important to really question this knee-jerk reaction that we are our own best experts,” says Vazire. “Personality is not who you think you are, it’s who you are. Some people think by definition that we are the experts on our personality because we get to write the story, but personality is not the story – it’s the reality. So, you do get to write your own story about how you think you are, and what you tell people about yourself, but there still is reality out there, and, guess what? Other people are going to see the reality, regardless of what story you believe.”

Personality, Vazire says, is pervasive in many things that we do – clothing choice, bedroom arrangement, Web site and Facebook profiles, for example. “Everything you touch you leave a mark of your personality,” she says. “You leave traces unintentionally. You give off hints of your personality that you don't even see yourself.”

Vazire’s study is published in the Feb. 2010 issue of the Journal of Personality and Social Psychology.

Personality is comprised of the underlying traits that drive behavior, Vazire says. The model she developed is called the self-other knowledge asymmetry (SOKA) model. To test it she called upon 165 volunteers who were given a number of different tasks. To obtain an objective measure of behavior, they took an IQ test; they all participated in a group discussion called a leaderless group discussion to see who emerged as the take-charge individual; and they took a Trier social stress test, in which trained experimenters with faux stern demeanors filmed participants in a narrow, cramped room, as they gave a two-minute public speaking exhibition on the topic of what I like and don’t like about my body. A sweat-inducer for many. Each participant also graded group members and him or herself on a 40-trait personality rating form.

Her model correctly predicted that self ratings would be more accurate for internal things, such as thoughts and feelings, sadness and anxiety, for example, than the ratings of friends and strangers.

“You probably know pretty well your anxiety level, whereas others might not be in the position to judge that because, after all, you can mask your inner feelings,” Vazire says. “Others, though, are often better than the self in things that deal with overt behavior.”

The self has difficulty in accurately judging itself in areas that are desirable or undesirable, what she calls evaluative traits. Intelligence, attractiveness, creativity are hard for the self to judge objectively because “there is so much at stake, meaning your life is going to be so much different if you are intelligent or not intelligent, attractive or not. Everybody wants to be seen as intelligent and attractive, but these desirable traits we’re not going to judge accurately in ourselves.”

The self is better at judging friends’ intelligence than its own “because it’s not that threatening to us to admit that our friends aren’t brilliant, but it’s more threatening to admit to ourselves that we’re not brilliant.”

Take attractiveness and your mirror. “We look in the mirror all the time, yet that’s not the same as looking at a photo of someone else,” Vazire says. “If we spent as much time looking at photos of others as we do ourselves we’d form a much more confident and clear impression of the other’s attractiveness than we would have of our own. Yet after looking in the mirror for five minutes we’re still left wondering, ‘Am I attractive or not?’ And still have no clue. And it’s not the case that we all assume that we’re beautiful, right?”

For some personality traits, she says we miss the point if we look at thoughts and feelings and ignore the behavior. Bullies, for instance, fit the SOKA model, because their thoughts and feelings tell them they’re insecure and want to be liked and admired, which is not a horrible, nasty notion. They cannot see their behavior as nasty and horrible, though, because their thoughts obscure their actions.

Similarly, if you think that you are warm and friendly, and your friends and family say even if you think along those lines, you don’t come across that way, you might pay more attention to your behaviors.

“I believe I’ve presented evidence that should make people think twice,” Vazire says. “On average, the people who know you best know you as well as you know yourself, no better, no worse than you. More importantly, there are things that both you know that they don’t know, and things that they know that you don’t know, and those lead to very interesting experiences and disagreements.”

(Photo: WUSTL)

Washington University in St. Louis

DNA SEQUENCING UNLOCKS RELATIONSHIPS AMONG FLOWERING PLANTS

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The origins of flowering plants from peas to oak trees are now in clearer focus thanks to the efforts of University of Florida researchers.

A study appearing online this week in the Proceedings of the National Academy of Sciences unravels 100 million years of evolution through an extensive analysis of plant genomes. It targets one of the major moments in plant evolution, when the ancestors of most of the world’s flowering plants split into two major groups.

Together the two groups make up nearly 70 percent of all flowering plants and are part of a larger clade known as Pentapetalae, which means five petals. Understanding how these plants are related is a large undertaking that could help ecologists better understand which species are more vulnerable to environmental factors such as climate change.

Shortly after the two groups split apart, they simultaneously embarked upon a rapid burst of new species that lasted 5 million years. This study shows how those species are related and sheds further light on the emergence of flowering plants, an evolutionary phenomenon described by Charles Darwin as an abominable mystery.

“This paper and others show flowering plants as layer after layer of bursts of evolution,” said Doug Soltis, study co-author and UF distinguished professor of biology. “Now it’s falling together into two big groups.”

Pentapetalae has enormous diversity and contains nearly all flowering plants. Its two major groups, superrosids and superasterids, split apart between 111 million and 98 million years ago and now account for more than 200,000 species. The superrosids include such familiar plants as hibiscus, oaks, cotton and roses. The superasterids include mint, azaleas, dogwoods and sunflowers.

Earlier studies were limited by technology and involved only four or five genes. Those studies hinted at the results found in the new study but lacked statistical support, said study co-author Pam Soltis, distinguished professor and Florida Museum of Natural History curator of molecular systematics and evolutionary genetics.

The new study at UF’s Florida Museum of Natural History analyzed 86 complete plastid genome sequences from a wide range of plant species. Plastids are the plant cell component responsible for photosynthesis.

Previous genetic analyses of Pentapetalae failed to untangle the relationships among living species, suggesting that the plants diverged rapidly over 5 million years. Researchers selected genomes to sequence based on their best guess of genetic relationships from the previous sequencing work.

Genome sequencing is more time-consuming for plants than animals because plastid DNA is about 10 times larger than the mitochondrial DNA used in studying animal genomes. But continual improvements in DNA sequencing technology are now allowing researchers to analyze those larger amounts of data more quickly.

The study provides an important framework for further investigating evolutionary relationships by providing a much clearer picture of the deep divergence that led to the split within flowering plants, which then led to speciation in the two separate branches.

Eventually, researchers hope to match these evolutionary bursts with geological and climatic events in the earth’s history. “I think we’re starting to get to a point with a dated tree where we could start looking at what was happening at some of those time frames,” Pam Soltis said.

University of Florida

CALTECH NEUROSCIENTISTS FIND BRAIN SYSTEM BEHIND GENERAL INTELLIGENCE

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A collaborative team of neuroscientists at the California Institute of Technology (Caltech), the University of Iowa, the University of Southern California (USC), and the Autonomous University of Madrid have mapped the brain structures that affect general intelligence.

The study, published the week of February 22 in the early edition of the Proceedings of the National Academy of Sciences, adds new insight to a highly controversial question: What is intelligence, and how can we measure it?

The research team included Jan Gläscher, first author on the paper and a postdoctoral fellow at Caltech, and Ralph Adolphs, the Bren Professor of Psychology and Neuroscience and professor of biology. The Caltech scientists teamed up with researchers at the University of Iowa and USC to examine a uniquely large data set of 241 brain-lesion patients who all had taken IQ tests. The researchers mapped the location of each patient's lesion in their brains, and correlated that with each patient's IQ score to produce a map of the brain regions that influence intelligence.

"General intelligence, often referred to as Spearman's g-factor, has been a highly contentious concept," says Adolphs. "But the basic idea underlying it is undisputed: on average, people's scores across many different kinds of tests are correlated. Some people just get generally high scores, whereas others get generally low scores. So it is an obvious next question to ask whether such a general ability might depend on specific brain regions."

The researchers found that, rather than residing in a single structure, general intelligence is determined by a network of regions across both sides of the brain.

"One of the main findings that really struck us was that there was a distributed system here. Several brain regions, and the connections between them, were what was most important to general intelligence," explains Gläscher.

"It might have turned out that general intelligence doesn't depend on specific brain areas at all, and just has to do with how the whole brain functions," adds Adolphs. "But that's not what we found. In fact, the particular regions and connections we found are quite in line with an existing theory about intelligence called the 'parieto-frontal integration theory.' It says that general intelligence depends on the brain's ability to integrate—to pull together—several different kinds of processing, such as working memory."

The researchers say the findings will open the door to further investigations about how the brain, intelligence, and environment all interact.

(Photo: PNAS)

California Institute of Technology (Caltech)

ANTI-DRINKING ADS CAN INCREASE ALCOHOL USE

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Public service advertising campaigns that use guilt or shame to warn against alcohol abuse can actually have the reverse effect, spurring increased drinking among target audiences, according to new research from the Indiana University Kelley School of Business.

Instead of the intended outcome, researchers in this first-of-its-kind study showed that the ads triggered an innate coping mechanism that enables viewers to distance themselves from the serious consequences of reckless drinking.

Anti- or "responsible" drinking campaigns have long been a mainstay of health departments, nonprofit organizations and even beverage companies. Yet alcohol abuse remains a persistent and growing problem linked to the deaths of approximately 79,000 people in the United States each year.

"The public health and marketing communities expend considerable effort and capital on these campaigns but have long suspected they were less effective than hoped," said Adam Duhachek, a marketing professor and co-author of the study. "But the situation is worse than wasted money or effort. These ads ultimately may do more harm than good because they have the potential to spur more of the behavior they're trying to prevent."

Duhachek's research specifically explores anti-drinking ads that link to the many possible adverse results of alcohol abuse, such as blackouts and car accidents, while eliciting feelings of shame and guilt. Findings show such messages are too difficult to process among viewers already experiencing these emotions -- for example, those who already have alcohol-related transgressions.

To cope, they adopt a defensive mindset that allows them to underestimate their susceptibility to the consequences highlighted in the ads; that is, that the consequences happen only to "other people." The result is they engage in greater amounts of irresponsible drinking, according to respondents.

"Advertisements are capable of bringing forth feelings so unpleasant that we're compelled to eliminate them by whatever means possible," said Duhachek. "This motivation is sufficiently strong to convince us we're immune to certain risks."

The findings are particularly relevant for U.S. universities, where alcohol abuse threatens the well-being of an entire generation, he said. Each year, drinking among college students contributes to an estimated 1,700 student deaths, 600,000 injuries, 700,000 assaults, 90,000 sexual assaults and 474,000 cases of unprotected sex.

The unintended negative impact of employing shame and guilt in these ads has implications for a wider range of health related messaging, from smoking cessation to preventing sexually transmitted diseases. According to Duhachek, shame- and guilt-inducing campaigns that seek to curb these behaviors can have the same unintentional backfire effects.

Duhachek encourages marketers looking to influence drinking and other behaviors to convey dire consequences along with messages of empowerment. For instance, providing strategies to control one's drinking or recalling instances where one resisted the temptation to engage in risky drinking behavior may provide a pathway to reducing these undesirable behaviors more effectively.

"If you're going to communicate a frightening scenario, temper it with the idea that it's avoidable," he said. "It's best to use the carrot along with the stick."

Duhachek developed the study with Nidhi Agrawal at the Kellogg School of Business at Northwestern University. They interviewed more than 1,200 undergraduate students after showing them shame- and guilt-inducing advertisements, which they specifically created for the research. To ensure no biases on the part of respondents, the team opted not to rely on existing campaigns.

(Photo: Indiana U.)

Indiana University Kelley School of Business

CU TEAM DISCOVERS TINY RNA MOLECULE WITH BIG IMPLICATIONS FOR THE ORIGIN OF LIFE

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The smallest RNA enzyme ever known to perform a cellular chemical reaction is described in a paper published this week in the Proceedings of the National Academy of Sciences. The paper was written by CU graduate student Rebecca Turk, research associate Nataliya Chumachenko and Professor Michael Yarus of the molecular, cellular and developmental biology department.

Cellular RNA can have hundreds or thousands of its basic structural units, called nucleotides. Yarus' team focused on a ribozyme -- a form of RNA that can catalyze chemical reactions -- with only five nucleotides.

Tom Blumenthal, a professor and chair of the MCDB department, noted that Tom Cech, a Nobel laureate and distinguished professor of chemistry and biochemistry at CU, and Professor Norman Pace of MCDB, independently discovered that RNA can act as an enzyme, carrying out chemical reactions. That "pioneering work" has been carried on further by Yarus, Blumenthal said.

Because proteins are complex, one vexing question is where the first proteins came from, Blumenthal said. "It now appears that the first catalytic macromolecules could have been RNA molecules, since they are somewhat simpler, were likely to exist early in the formation of the first life forms, and are capable of catalyzing chemical reactions without proteins being present," he said.

"In this paper the Yarus group has made the amazing discovery that even an extremely tiny RNA can by itself catalyze a key reaction that would be needed to synthesize proteins," Blumenthal said. "Nobody expected an RNA molecule this small and simple to be able to do such a complicated thing as that."

The finding adds weight to the "RNA World" hypothesis, which proposes that life on Earth evolved from early forms of RNA. "Mike Yarus has been one of the strongest proponents of this idea, and his lab has provided some of the strongest evidence for it over the past two decades," Blumenthal said.

Yarus noted that the RNA World hypothesis was complicated by the fact that RNA molecules are hard to make. "This work shows that RNA enzymes could have been far smaller, and therefore far easier to make under primitive conditions, than anyone has expected."

If very simple RNA molecules such as the product of the Yarus lab could have accelerated chemical reactions in Earth's primordial stew, the chances are much greater that RNA could direct and accelerate biochemical reactions under primitive conditions.

Before the advent of RNA, most biologists believe, there was a simpler world of chemical replicators that could only make more of themselves, given the raw materials of the time, Yarus said.

"If there exists that kind of mini-catalyst, a ‘sister' to the one we describe, the world of the replicators would also jump a long step closer and we could really feel we were closing in on the first things on Earth that could undergo Darwinian evolution," Yarus said.

"In other words, we may have taken a substantial step toward the very origin of Earthly life," he said. "However, keep well in mind that the tiny replicator has not been found, and that its existence will be decided by experiments not yet done, perhaps not yet imagined."

"Dr. Yarus has brought an innovative approach to bear on the key question of how complex processes originated," said Michael Bender, a biologist who oversees protein synthesis grants at the National Institutes of Health's National Institute of General Medical Sciences. "By showing that a tiny segment of RNA can perform a key step of protein synthesis, this study has provided evidence that fundamental, protein-mediated cellular processes may have arisen from RNA-based mechanisms."

(Photo: Emily Krauter)

University of Colorado at Boulder

CU PHYSICISTS USE ULTRA-FAST LASERS TO OPEN DOORS TO NEW TECHNOLOGIES UNHEARD OF JUST YEARS AGO

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Recent breakthroughs by their team at JILA, a joint institute of CU-Boulder and the National Institute of Standards and Technology, have paved the way on how to build a tabletop X-ray laser that could be used for super high-resolution imaging, while also giving scientists a new way to peer into a single cell and gain a better understanding of the nanoworld.

Both of these feats could lead to major breakthroughs in many fields including medicine, biology and nanotechnology development.

"Our goal is to create a laser beam that contains a broad range of X-ray wavelengths all at once that can be focused both in time and space," Murnane said. "If we have this source of coherent light that spans a huge region of the electromagnetic spectrum, we would be able to make the highest resolution light-based tabletop microscope in existence that could capture images in 3-D and tell us exactly what we are looking at. We're very close."

Murnane and Kapteyn presented highlights of their research today at the American Association for the Advancement of Science, or AAAS, annual meeting in San Diego, during a panel discussion about the history and future of laser technology titled "Next Generation of Extreme Optical Tools and Applications."

Most of today's X-ray lasers require so much power that they rely on fusion laser facilities the size of football stadiums or larger, making their use impractical. Murnane and Kapteyn generate coherent laser-like X-ray beams by using an intense femtosecond laser and combining hundreds or thousands of visible photons together. And the key is they are doing it with a desktop-size system.

They can already generate laser-like X-ray beams in the soft X-ray region and believe they have discovered how to extend the process all the way into the hard X-ray region of the electromagnetic spectrum.

"If we can do this, it could lead to all kinds of possibilities," Kapteyn said. "It might make it possible to improve X-ray imaging resolution at your doctor's office by a thousand times. The X-rays we get in the hospital now are limited. For example, they can't detect really small cancers because the X-ray source in your doctor's office is more like a light bulb, not a laser. If you had a bright, focused laser-like X-ray beam, you could image with far higher resolution."

Their method can be thought of as a coherent version of the X-ray tube, according to Murnane. In an X-ray tube, an electron is boiled off a filament, then it is accelerated in an electric field before hitting a solid target, where the kinetic energy of the electron is converted into incoherent X-rays. These incoherent X-rays are like the incoherent light from a light bulb or flashlight -- they aren't very focused.

In the tabletop setup, instead of boiling an electron from a filament, they pluck part of the quantum wave function of an electron from an atom using a very intense laser pulse. The electron is then accelerated and slammed back into the ion, releasing its energy as an X-ray photon. Since the laser field controls the motion of the electron, the X-rays emitted can retain the coherence properties of a laser, Murnane said.

Being able to build a tabletop X-ray laser is just the beginning, said Kapteyn.

"An analogy that is pretty close to what is going on in this field is the MRI, which started as just a fundamental investigation," said Kapteyn. "People then started using it for microscopy, and then it progressed into a medical diagnostic technique."

(Photo: CUB)

University of Colorado at Boulder

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