Expressions of trust

In the movie “The Social Network,” the story line contrasts the speed with which Mark Zuckerberg develops and launches a university-wide site against the terse e-mails he uses to stall the Winklevoss twins for weeks. By limiting contact to e-mails, the movie shows how Zuckerberg kept the twins thinking he was still working on their project when he’d already moved beyond their original idea.

The lack of communication between the main characters of the movie highlights one of the reasons personal meetings remain popular in an age of almost instantaneous electronic contact: people like seeing the other person’s face to gauge the information not being shared over the phone or in the printed word. One study has found that people would willingly invest their money with someone who has a bad reputation if his/her facial features conveyed the message that he/she was actually trustworthy.

A forthcoming study in which researchers tracked mock stock transactions done in person, by video, by audio only or through text chatting showed that people were far more likely to lie about stock information in text-only interactions. The investors in the experiment had fewer complaints of being deceived about the transactions if they had interacted through video, on audio or in person.

In an effort to learn more about how facial features can evoke a sense of trust, a recent study from researchers at the Charles University in the Czech Republic focused on eye color to see what role it plays in determining trustworthiness. They asked over 200 students to rate 80 photos of men and women on a scale from very trustworthy to very untrustworthy. The images shown featured only people with either brown eyes or blue eyes.

The researchers then digitally altered the same 80 photos so that the blue-eyed people were now brown-eyed and vice versa. A second set of students then rated these images on the same scale.

The results showed that the brown-eyed images were considered more trustworthy than the blue-eyed images, an attention-grabbing partial finding. The team then analyzed the images they had used to try and figure out the underlying reason behind the emphasis on eye color. They identified similar face shapes and other features that suggested that these factors were the real reasons for the trust rating rather than eye color.

“Although the brown-eyed faces were perceived as more trustworthy than the blue-eyed ones, it was not brown eye color per se that caused the stronger perception of trustworthiness but rather the facial features associated with brown eyes,” the team wrote in their paper which appeared on Jan. 9 in the journal Plos One. “It seems that relatively smaller eyes and a smaller mouth with downward-pointing corners are the facial traits that cause the lower perceived trustworthiness of blue-eyed males.”

The Czech researcher’s findings echo the results from an earlier British study that suggests cartoon villains have similar facial features for a reason. Consider that many of these characters have angular features and triangular faces that end in pointed chins. The researchers noted that people perceive the downward triangle shape of the villains’ faces as threatening.

E-mail the author at [email protected].