Sex. Race. Age. Emotional State. Personality. These are just some of the characteristics the human brain gleans about another person through split-second visual perceptions—a process studied extensively at NYU's Social Cognitive & Neural Sciences Lab.

In this video, lab director Jonathan Freeman discusses how we make snap judgements about people's appearance—without even knowing that we're doing it. His previous research found that the speed with which test subjects categorized a female politician's gender could predict whether she wins or loses her election, and that people were more likely to consider a mixed-race person "black" if he appeared low-status apparel, like a janitor's uniform.

Freeman pioneered software that can track the brain's decision-making process by analyzing the millimeters of movement of a test subject's mouse cursor—technology that was used in a recent experiment exploring the amygdala's role in determining whether a given face is judged to be trustworthy.