Thursday, March 26, 2009

Why We Have Difficulty Recognizing Faces In Photo Negatives


ScienceDaily (Mar. 25, 2009) — Humans excel at recognizing faces, but how we do this has been an abiding mystery in neuroscience and psychology. In an effort to explain our success in this area, researchers are taking a closer look at how and why we fail.
A new study from MIT looks at a particularly striking instance of failure: our impaired ability to recognize faces in photographic negatives. The study, which appears in the Proceedings of the National Academy of Sciences this week, suggests that a large part of the answer might lie in the brain's reliance on a certain kind of image feature.
The work could potentially lead to computer vision systems, for settings as diverse as industrial quality control or object and face detection. On a different front, the results and methodologies could help researchers probe face-perception skills in children with autism, who are often reported to experience difficulties analyzing facial information.
Anyone who remembers the days before digital photography has probably noticed that it's much harder to identify people in photographic negatives than in normal photographs. "You have not taken away any information, but somehow these faces are much harder to recognize," says Pawan Sinha, an associate professor of brain and cognitive sciences and senior author of the PNAS study.
Sinha has previously studied light and dark relationships between different parts of the face, and found that in nearly every normal lighting condition, a person's eyes appear darker than the forehead and cheeks. He theorized that photo negatives are hard to recognize because they disrupt these very strong regularities around the eyes.
To test this idea, Sinha and his colleagues asked subjects to identify photographs of famous people in not only positive and negative images, but also in a third type of image in which the celebrities' eyes were restored to their original levels of luminance, while the rest of the photo remained in negative.
Subjects had a much easier time recognizing these "contrast chimera" images. According to Sinha, that's because the light/dark relationships between the eyes and surrounding areas are the same as they would be in a normal image.
Similar contrast relationships can be found in other parts of the face, primarily the mouth, but those relationships are not as consistent. "The relationships around the eyes seem to be particularly significant," says Sinha.
Other studies have shown that people with autism tend to focus on the mouths of people they are looking at, rather than the eyes, so the new findings could help explain why autistic people have such difficulty recognizing faces, says Sinha.
The findings also suggest that neuronal responses in the brain may be based on these relationships between different parts of the face. The team found that when they scanned the brains of people performing the recognition task, regions associated with facial processing (the fusiform face areas) were far more active when looking at the contrast chimeras than when looking at pure negatives.
Other authors of the paper are Sharon Gilad of the Weizmann Institute of Science in Israel and MIT postdoctoral associate Ming Meng, both of whom contributed equally to the work..
The research was funded by the Alfred P. Sloan Foundation and the Jim and Marilyn Simons Foundation.
Adapted from materials provided by Massachusetts Institute of Technology.

Saturday, March 21, 2009

Contrary To Widely Held Beliefs, Romance Can Last In Long-term Relationships, Say Researchers

ScienceDaily (Mar. 21, 2009) — Romance does not have to fizzle out in long-term relationships and progress into a companionship/friendship-type love, a new study has found. Romantic love can last a lifetime and lead to happier, healthier relationships.
"Many believe that romantic love is the same as passionate love," said lead researcher Bianca P. Acevedo, PhD, then at Stony Brook University (currently at University of California, Santa Barbara). "It isn't. Romantic love has the intensity, engagement and sexual chemistry that passionate love has, minus the obsessive component. Passionate or obsessive love includes feelings of uncertainty and anxiety. This kind of love helps drive the shorter relationships but not the longer ones."
These findings appear in the March issue of Review of General Psychology, published by the American Psychological Association.
Acevedo and co-researcher Arthur Aron, PhD, reviewed 25 studies with 6,070 individuals in short- and long-term relationships to find out whether romantic love is associated with more satisfaction. To determine this, they classified the relationships in each of the studies as romantic, passionate (romantic with obsession) or friendship-like love and categorized them as long- or short-term.
The researchers looked at 17 short-term relationship studies, which included 18- to 23-year-old college students who were single, dating or married, with the average relationship lasting less than four years. They also looked at 10 long-term relationship studies comprising middle-aged couples who were typically married 10 years or more. Two of the studies included both long- and short-term relationships in which it was possible to distinguish the two samples.
The review found that those who reported greater romantic love were more satisfied in both the short- and long-term relationships. Companion-like love was only moderately associated with satisfaction in both short- and long-term relationships. And those who reported greater passionate love in their relationships were more satisfied in the short term compared to the long term.
Couples who reported more satisfaction in their relationships also reported being happier and having higher self-esteem.
Feeling that a partner is "there for you" makes for a good relationship, Acevedo said, and facilitates feelings of romantic love. On the other hand, "feelings of insecurity are generally associated with lower satisfaction, and in some cases may spark conflict in the relationship. This can manifest into obsessive love," she said.
This discovery may change people's expectations of what they want in long-term relationships. According to the authors, companionship love, which is what many couples see as the natural progression of a successful relationship, may be an unnecessary compromise. "Couples should strive for love with all the trimmings," Acevedo said. "And couples who've been together a long time and wish to get back their romantic edge should know it is an attainable goal that, like most good things in life, requires energy and devotion."
Journal reference:
Bianca P. Acevedo and Arthur Aron. Does a long-term relationship kill romantic love? Review of General Psychology, 2009; 13 (1): 59 DOI: 10.1037/a0014226
Adapted from materials provided by American Psychological Association, via EurekAlert!, a service of AAAS.

Friday, March 20, 2009

Stranger Knows Best: Other People Know More About What Will Make Us Happy Than We Do

ScienceDaily (Mar. 20, 2009) — Want to know what will make you happy? Then ask a total stranger -- or so says a new study from Harvard University, which shows that another person's experience is often more informative than your own best guess.

The study, which appears in the current issue of Science, was led by Daniel Gilbert, professor of psychology at Harvard and author of the 2007 bestseller "Stumbling on Happiness," along with Matthew Killingsworth and Rebecca Eyre, also of Harvard, and Timothy Wilson of the University of Virginia.
"If you want to know how much you will enjoy an experience, you are better off knowing how much someone else enjoyed it than knowing anything about the experience itself," says Gilbert. "Rather than closing our eyes and imagining the future, we should examine the experience of those who have been there."
Previous research in psychology, neuroscience, and behavioral economics has shown that people have difficulty predicting what they will like and how much they will like it, which leads them to make a wide variety of poor decisions. Interventions aimed at improving the accuracy with which people imagine future events have been generally unsuccessful.
So rather than trying to improve human imagination, Gilbert and his colleagues sought to eliminate it from the equation by asking people to predict how much they would enjoy a future event about which they knew absolutely nothing -- except how much a total stranger had enjoyed it. Amazingly enough, those people made extremely accurate predictions.
In one experiment, women predicted how much they would enjoy a "speed date" with a man. Some women read the man's personal profile and saw his photograph, and other women learned nothing whatsoever about the man, but did learn how much another woman (whom they had never met) had enjoyed dating him. Women who learned about a previous woman's experience did a much better job of predicting their own enjoyment of the speed date than did woman who studied the man's profile and photograph.
Interestingly, both groups of women mistakenly expected the profile and photo to lead to greater accuracy, and after the experiment was over both groups said they would strongly prefer to have the profile and photograph of their next date.
In the second experiment, two groups of participants were asked to predict how they would feel if they received negative personality feedback from a peer. Some participants were shown a complete written copy of the feedback. Other were shown nothing, and learned only how a total stranger had felt upon receiving the feedback. The latter group more accurately predicted their own reactions to the negative feedback. Once again, participants mistakenly guessed that a written copy of the feedback would be more informative than knowledge of a total stranger's experience.
"People do not realize what a powerful source of information another person's experience can be," says Gilbert, "because they mistakenly believe that everyone is remarkably different from everyone else. But the fact is that an alien who knew all the likes and dislikes of a single human being would know a great deal about the species. People believe that the best way to predict how happy they will be in the future is to know what their future holds, but what they should really want to know is how happy those who've been to the future actually turned out to be."
Gilbert's research was funded by the National Science Foundation.
Adapted from materials provided by Harvard University, via EurekAlert!, a service of AAAS.

Liking Sweets Makes Sense For Kids


ScienceDaily (Mar. 20, 2009) — As any parent knows, children love sweet-tasting foods. Now, new research from the University of Washington and the Monell Center indicates that this heightened liking for sweetness has a biological basis and is related to children's high growth rate.
"The relationship between sweet preference and growth makes intuitive sense because when growth is rapid, caloric demands increase. Children are programmed to like sweet taste because it fills a biological need by pushing them towards energy sources," said Monell geneticist Danielle Reed, PhD, one of the study authors.
Across cultures, children prefer higher levels of sweetness in their foods as compared to adults, a pattern that declines during adolescence. To explore the biological underpinnings of this shift, Reed and University of Washington researcher Susan Coldwell, PhD, looked at sweet preference and biological measures of growth and physical maturation in 143 children between the ages of 11 and 15.
The findings, reported in the journal Physiology & Behavior, suggest that children's heightened liking for sweet taste is related to their high growth rate and that sweet preferences decline as children's physical growth slows and eventually stops.
Based on the results of sensory taste tests, children were classified according to their sweet taste preference into a 'high preference' or 'low preference' group. Children in the 'low preference' group also had lower levels of a biomarker (type I collagen cross-linked N-teleopeptides; NTx) associated with bone growth in children and adolescents.
"This gives us the first link between sweet preference and biological need," said Reed. "When markers of bone growth decline as children age, so does their preference for highly sweet solutions."
Other biological factors associated with adolescence, such as puberty or sex hormone levels, were not associated with sweet preference.
"We now know that sweet preference is related to physical growth. The next step is to identify the growth-related factor that is signaling the brain to influence sweet preference," said study lead author Coldwell, Washington Dental Service Endowed Professor and Associate Professor of Dental Public Health Sciences at the University of Washington School of Dentistry.
The research was funded by a grant to the University of Washington from the National Institute of Dental and Craniofacial Research (National Institutes of Health).
Adapted from materials provided by Monell Chemical Senses Center, via EurekAlert!, a service of AAAS.

Language Of Music Really Is Universal, Study Finds


ScienceDaily (Mar. 20, 2009) — Native African people who have never even listened to the radio before can nonetheless pick up on happy, sad, and fearful emotions in Western music, according to a new report published online on March 19th in Current Biology. The result shows that the expression of those three basic emotions in music can be universally recognized, the researchers said.
"These findings could explain why Western music has been so successful in global music distribution, even in music cultures that do not as strongly emphasize the role of emotional expression in their music," said Thomas Fritz of the Max-Planck-Institute for Human Cognitive and Brain Sciences.
The expression of emotions is a basic feature of Western music, and the capacity of music to convey emotional expressions is often regarded as a prerequisite to its appreciation in Western cultures, the researchers explained. In other musical traditions, however, music is often appreciated for other qualities, such as group coordination in rituals.
In the new study, Fritz, Stefan Koelsch, and their colleagues wanted to find out whether the emotional aspects of Western music could be appreciated by people who had no prior exposure to it. Previous studies had asked similar questions about people with little experience with a particular musical form, for instance Westerners listening to Hindustani music, they said. But to really get at musical universals requires participants who are completely naïve to Western music.
Fritz enlisted members of the Mafa, one of about 250 ethnic groups in Cameroon. He traveled to the extreme north of the Mandara mountain ranges, where they live, with a laptop and sun collector to supply electricity in his backpack.
Their studies showed that both Western and Mafa listeners, who had never before heard Western music, could recognize emotional expressions of happiness, sadness, and fear in the music more often than would be expected by chance. However, they report that the Mafa showed considerable variability in their performance, with two of twenty-one study participants performing at chance level.
Both groups relied on similar characteristics of music to make those calls; both Mafas and Westerners relied on temporal cues and on mode for their judgment of emotional expressions, although this pattern was more marked in Western listeners.
By manipulating music, the researchers also found that both Western listeners and African listeners find original music more pleasant than altered versions. That preference is probably explained in part by the increased sensory dissonance of the manipulated tunes.
"In conclusion," the researchers wrote, "both Mafa and Western listeners showed an ability to recognize the three basic emotional expressions tested in this study from Western music above chance level. This indicates that these emotional expressions conveyed by the Western musical excerpts can be universally recognized, similar to the largely universal recognition of human emotional facial expression and emotional prosody." Prosody refers to the rhythm, stress, and intonation of connected speech.
The authors include Thomas Fritz, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Sebastian Jentschke, UCL Institute of Child Health, London, UK; Nathalie Gosselin, Universite´ de Montreal, Montreal, Canada; Daniela Sammler, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Isabelle Peretz, Universite´ de Montreal, Montreal, Canada; Robert Turner, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Angela D. Friederici, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Stefan Koelsch, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, University of Sussex, Falmer, UK.
Journal reference:
Thomas Fritz, Sebastian Jentschke, Nathalie Gosselin, Daniela Sammler, Isabelle Peretz, Robert Turner, Angela D. Friederici, Stefan Koelsch. Universal Recognition of Three Basic Emotions in Music. Current Biology, 2009; DOI: 10.1016/j.cub.2009.02.058
Adapted from materials provided by Cell Press, via EurekAlert!, a service of AAAS.

Wednesday, March 18, 2009

Key To Happiness Is Gratitude, And Men May Be Locked Out

SOURCE

ScienceDaily (Mar. 19, 2009) — With Mother’s Day, Father’s Day and high school and college graduations upcoming, there will be plenty of gift-giving and well wishes. When those start pouring in, let yourself be grateful—it’s the best way to achieve happiness according to several new studies conducted by Todd Kashdan, associate professor of psychology at George Mason University.
Gratitude, the emotion of thankfulness and joy in response to receiving a gift, is one of the essential ingredients for living a good life, Kashdan says. Kashdan’s most recent paper, which was recently published online at the Journal of Personality, reveals that when it comes to achieving well-being, gender plays a role. He found that men are much less likely to feel and express gratitude than women.
“Previous studies on gratitude have suggested that there might be a difference in gender, and so we wanted to explore this further—and find out why. Even if it is a small effect, it could make a huge difference in the long run,” says Kashdan.
In one study, Kashdan interviewed college-aged students and older adults, asking them to describe and evaluate a recent episode in which they received a gift. He found that women compared with men reported feeling less burden and obligation and greater levels of gratitude when presented with gifts. In addition, older men reported greater negative emotions when the gift giver was another man.
“The way that we get socialized as children affects what we do with our emotions as adults,” says Kashdan. “Because men are generally taught to control and conceal their softer emotions, this may be limiting their well-being.”
As director of the Laboratory for the Study of Social Anxiety, Character Strengths, and Related Phenomena at Mason, Kashdan is interested in the assessment and cultivation of well-being, curiosity, gratitude and meaning and purpose in life. He has been active in the positive psychology movement since 2000, when he taught one of the first college courses on the science of happiness.
Kashdan says that if he had to name three elements that are essential for creating happiness and meaning in life it would be meaningful relationships, gratitude, and living in the present moment with an attitude of openness and curiosity. His book “Curious?,” which outlines ways people can enhance and maintain the various shades of well-being, is scheduled for release in April 2009 with HarperCollins.
Adapted from materials provided by George Mason University.

Writing After Terrorist Attack Has Positive Medium Term Effects

ScienceDaily (Mar. 18, 2009) — A new study has analysed the expressive writing of terrorism victims to analyse their psychosocial processes following the terrorist attacks in New York and Madrid. Despite the cultural differences of the people involved, the results show that the feelings and thoughts experienced following this type of traumatic event are universal.

The people who experienced the September 11 terrorist attacks in New York and the March 11 2004 train attacks in Madrid needed to be able to express their feelings, thoughts and emotions. The aim of the study published in the International Journal of Clinical and Health Psychology was to compare how people from both nations reacted to such violent acts through expressive writing.
"After the Madrid attacks we were unfortunate enough to be able to ask people who had lived through this experience, either directly or indirectly, what they thought and how they felt following the terrorist attacks," Itziar Fernández, the study's author and a professor at the National University of Distance Education (UNED), told SINC.
"Following the attacks, there was a great fear that people would be affected by post-traumatic stress disorder. In the end, however, although they were in shock, people were able to deal with had happened and adapt to the situation," says the researcher.
Based on the comments recorded by 325 people living in the United States and 333 in Spain, the researcher and her team looked into how both groups put their feelings and thoughts into words.
A linguistic analysis of the texts, carried out by using the Linguistic Inquiry and Word Count (LIWC) programme, showed that the victims who benefited most from recording the traumatic events were those who use more cognitive words (introspective and causal ones), use a high number of positive emotional words, and changed the use of pronouns and references to themselves.
The results show that feelings about the events (anger, impotence, fear) were similar between the two countries during a period between the third and eighth weeks after the attacks, both inclusive.
However, the data collected does show a significant difference. "While the Americans had a more individualistic view of events, the Spaniards talked more about social processes." For example, there were not the same enormous public demonstrations following September 11 as there were following the attacks in Spain.
The study concludes that writing about a traumatic event can have positive effects over the medium term (from two months afterwards). Although the participants' symptoms worsened over the short term (relating an event makes people relive it, and worsens their negative emotions), they felt better and paid less visits to the doctor over the medium and long term.
The effect was the opposite in the case of excessive consumption of media coverage of such an event, however. Data about news consumption throughout the population following the attacks showed that, over the long term (two months after the Madrid attacks), people who were repetitively viewing images of the attacks felt worse than those who rarely watched the television.
Tackling post-traumatic stress
The benefits of talking about traumatic events forms part of cultural belief systems. Therapists always seek to make people reconstruct a narrative and a testimony about what has happened. They are asked to talk about their lives before the traumatic event, and to reconstruct images and their sensations and feelings in order to give them meaning (why and how the event took place).
The first studies of post-traumatic stress disorder (PTSD) were conducted following the Vietnam War (1958-1975). It is a psychological illness classified within the group of anxiety disorders, which arises as a result of exposure to a traumatic event involving physical harm.
PTSD, which is diagnosed two months after a stressful life event, is a severe emotional reaction. It is characterised by symptoms such as loss of appetite, sadness and disturbed sleep, and lasts for more than two months after the event.
Journal reference:
Itziar Fernández, Darío Páez y James W. Pennebaker. Comparison of expressive writing after the terrorist attacks of September 11th and March 11th. International Journal of Clinical and Health Psychology, Vol. 9, Nº 1, pp.89-103, 2009
Adapted from materials provided by Plataforma SINC, via AlphaGalileo.