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Key points
- Someone who is lying may "overdo" eye contact to appear more truthful.
- When a person is interested in something or someone, their pupils will dilate.
- A direct stare can be interpreted as a threat or an invitation, depending on the perception of the one being stared at.
There has been considerable research on how nonverbal cues, particularly those coming from the eyes, affects our behavior.
Here are five interesting results:
1. Eye-to-eye contact causes arousal.
Staring directly into someone’s eyes causes an arousal reaction. How that arousal is interpreted, however, depends on the parties involved and the circumstances. Being stared at by a stranger who appears large or ominous can be seen as a threat and elicit a fear response. This is common in social animals. A direct stare from a human to a dog or an ape can be interpreted as a threat from the large (and strange) human. However, the gaze of a potential sexual partner causes arousal that can be interpreted positively—as a sexual invitation.
2. The eyes will tell you if a smile is real or not.
Psychologist Paul Ekman has distinguished between smiles that represent genuine happiness (“Duchenne” smiles) and fake smiles that might be used to feign happiness, or cover some other emotion. The key to telling a fake smile from a real one is in the eyes. When forming real smiles, the eyes narrow and create lines, or “crow’s feet,” at the outer corners.
3. Pupil dilation is a sign of interest (and it can make you sexy).
When we are interested in something or someone our pupils will dilate. In one study, a woman’s eyes were altered to make her pupils look dilated. The exact same photos of the woman with dilated eyes was rated as more attractive than those with normal-size pupils.
4. Mutual gaze is a sign of love.
Research on love and attraction has found that mutual gaze—staring into each other’s eyes—is a good predictor of two individuals being “in love.”
5. Eye contact is a valid sign of deception, but not in the way that you think.
Everyone assumes that a liar won’t look you in the eye, but research on the nonverbal cues associated with deception suggests that a liar engages in more eye contact than a truth-teller. The explanation is that the deceiver goes the extra mile to try to convince you of his or her veracity and so “overdoes” the eye contact in order to appear truthful.
