Shy people may be hesitant to look you in the eye, but they seem to have a superior ability to recognize certain facial expressions, a new study suggests.

In the study, college-age adults who were shy were better able to recognize expressions of sadness and fear compared with those who were not shy.

The findings were surprising, said study researcher Laura Graves O'Haver, a doctoral student at Southern Illinois University at Carbondale, given that previous work has found shy people tend to misinterpret facial expressions. However, this earlier work was typically performed on children, and the ability to recognize facial expressions may change with age, Graves O'Haver said.

The new results put a positive twist on a trait that is usually considered unfavorable, she said.

"We tend to give shy people a bad rap," but the new study suggests there are some strengths to being shy, Graves O'Haver said. "It might be nice to focus on those strengths."

Graves O'Haver presented her findings this month at the American Psychological Association meeting in Orlando, Fla.

Graves O'Haver analyzed information from 241 college students (average age of 19) who took an online survey. Participants were shown 110 pictures of faces and asked to identify the facial expression represented by each picture (happy, sad, anger, fear, surprise, disgust and a neutral expression.)

To determine their level of shyness, participants were also asked whether certain statements were true for them, such as "I feel tense with people I don’t know well," "I find it difficult to ask for information," and "I'm uncomfortable at parties." [ Life's Extremes: Outgoing vs. Shy ]

Overall, people were able to identify the facial expressions quite well, with an 81 percent accuracy rate.

People with high levels of shyness were more accurate at identifying facial expressions of sadness and fear than those with low levels of shyness.

When asked how they were feeling during the study, shy people were more likely to be in a negative mood. This could, in part, explain the results, because studies have found that people in a bad mood tend to see other things in a negative light, "kind of like the opposite of rose-colored glasses," Graves O'Haver said.

It's also possible the superior ability to recognize sad and fearful facial expressions can contribute to people's shyness, Graves O'Haver said. If shy people see negative emotions on people's faces to a greater degree, "that could make you feel shy," Graves O'Haver said. "You might want to limit how much you look at faces," she said.

However, Graves O'Haver stressed the study only shows an association, and not a cause-effect link.

And because the study was conducted online, it's not clear how well the results would translate to a real-world situation, Graves O'Haver said. She would like to conduct another study in which the experiments more closely resemble a real-life conversation, perhaps through using videos instead of pictures.

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Beware the bedroom eyes, guys — new research suggests that a heavy-lidded, seductive gaze makes you seem less trustworthy to both men and women.

The study finds that guys with an open, normal gaze are preferred for a long-term relationship by women and as a business partner or neighbor by men. Women and men alike perceived the eyes-half-closed look as an attempt to secure a fling rather than a long-term relationship.

"A lot is conveyed in a glance," study researcher Daniel Kruger, a psychology professor at the University of Michigan, told LiveScience.

Large eyes convey childlike qualities such as naivety, sincerity and vulnerability. Gaze and pupil size also convey personality traits and mood, including extroversion and sexual arousal. With eyes conveying so much, Kruger and his colleagues wondered: What about eyelids?

Kruger and his co-author Jory Piglowski, also of the University of Michigan, took photographs of two men, both white and in their early 20s, with eyes open and half-open. They used computer-editing software to overlay the photographs so that they were identical in all aspects except for eye openness.

In two studies, the first with 239 undergraduate men and women and the second with 161 undergraduate participants, the researchers showed volunteers the photographs and asked the female participants to rate them on attractiveness for a short-term relationship, long-term relationship and brief affair (or fling). Women were also asked whether they'd like each man to be the father of her child or whether they'd trust him to accompany her sister on a long trip. Men were asked if they'd like the man as a son-in-law or whether they'd be okay with him traveling with their girlfriend on a long trip. They were also asked if they'd like the man as a business partner or neighbor.

The results showed that the squinty-eyed guy was less appealing as a long-term relationship prospect than the guy with the open gaze. The heavy-lidded man was seen as pursuing a short-term mating strategy — in other words, a fling rather than a relationship, the participants indicated. Unfortunately, the look didn't give him much of an edge: Men with a wider-eyed look were ranked as more attractive even for a brief affair. [ The Sex Quiz: Myths, Taboos & Bizarre Facts ]

Men were less likely to want the seductive gazer as a neighbor or business partner, and women were less likely to say they'd want to marry him, with 71 percent picking the open-eyed guy instead. Open-eyed guys were also seen as more trustworthy when accompanying a woman on a trip.

The researchers also picked two literary descriptions from British Romantic literature, one of a cad or dark hero (George Staunton from Walter Scott's 1818 book "The Heart of Midlothian) and one of an upstanding hero (Waverley, from the book "Waverley" by the same author). When they asked the participants to match the man to the description, they matched the squinter to the cad and the open-eyed guy to the knight-in-shining-armor type.

The seductive gaze may well convey a sense of maturity and sexual readiness, given that larger eyes are associated with youth, Kruger said. But the study, published in the April issue of the journal Personality and Individual Differences, suggests that an all-around seductive look "can come back to bite you," Kruger said. He and his colleagues have since conducted a similar study using female faces and shown the same results.

"You don't gain so much of an advantage by doing this [expression] unless you're already engaged with someone who is interested in you, or who you have a chancewith," Kruger said. "So don't overuse it."

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Aspects of your personality can be revealed in a heartbeat, literally, a new study from Germany suggests.

The study identified heartbeat "signatures" — wave patterns in the heart's electrical activity — that were linked with personality traits.

People with certain heartbeat signatures scored higher on tests of neuroticism — meaning these individuals tend to experience more negative emotions, such as anxiety and a depressed mood. They also tended to experience fewer positive emotions, including happiness and cheerfulness. Measures of the heart's electrical activity could also be used to predict people's agreeableness, a personality trait that describes how compassionate or empathetic an individual is.

The results suggest such heartbeat signatures may provide a way to measure personality that is more objective that current methods, the researchers say. Personality is commonly assessed using questionnaires, but these are subject to bias — people may choose responses that they think are more acceptable for their gender, for instance, or they may misperceive their own traits, the researchers said.

"We hope that with this method, we have found something that is perhaps more accurate, and more relatable, than many other measures of personality," said study researcher Stefan Koelsch, a professor of biological psychology at the Freie Universität Berlin.

Researchers may also be able to identify heartbeat signatures that are characteristic of certain emotional disorders, such as depression, or of cardiovascular diseases, Koelsch said. Such signatures could one day help diagnose these disorders, or identify people at risk for them, he said. 

The study involved 425 university students ages 18 to 33. The students completed personality tests, and had their heart electrical activity measured using electrocardiography.

Personality traits may influence the heart in a number of ways — either through direct nerve connections between the brain and the heart, or through breathing patterns or release of particular hormones, Koelsch said.

Previously, Koelsch and colleagues found a link between certain heart electrical activity patterns and people with cold" personalities, who tend not to show emotion. In the new study, similar patterns were seen among those with high scores in neuroticism and low scores in positive emotion.

Although Koelsch suspects that this type of electrical pattern is not particularly healthy, future research is needed to confirm this. Other studies have linked emotional states such as depression and anxiety to heart disease and high blood pressure.

Eventually, Koelsch hopes to be able to be able to see whether certain interventions, such as listening to music or watching films, change emotional states and the heart's electrical activity, he said.

The study was published Feb. 21 in the journal PLoS ONE.

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