For the first experiment the researchers had subjects roam New York City streets wearing Google Glass so they could record their visual fields. What the researchers found was that those who identified as upper-class looked at others on the street just about as frequently as those who said they were working-class, but the upper-class individuals did not hold their gaze on others for as long.
Smart glasses, however, only really measure the direction in which you're looking. So, to be more precise in the second experiment, the researchers used eye-tracking technology on subjects as they looked at photos of busy streets.
This time, those who identified as less wealthy spent more time looking at people in the photos, while the upper-class individuals were more likely to dwell on "things."
At this point the researchers had clearly defined a trend, but they still wanted to confirm whether the difference in behavior was a conscious choice. "It may be that class affects only deliberate aspects of attention — such that higher-class individuals consciously choose to devote less attention to other people than do lower-class individuals," they report. "Or social class may also influence spontaneous attentional processes that occur independently of voluntary control."
They explored the question using a "flicker paradigm," meaning they showed nearly 400 participants recruited online pairs of images that quickly alternated back and forth. The images were of everyday objects like plants and clothing, as well as human faces, and most pairs contained subtle differences. The goal of the participant was to identify those differences as quickly as possible.
As it turned out, when one of the objects was different in the two images, the upper- and working-class participants had similar reaction times. When it came to changes in faces, however, upper-class subjects were slower to detect them.