Paul Ekman is an American psychologist and professor emeritus at the University of California, San Francisco who is a pioneer in the study of emotions and their relation to facial expressions. He was ranked 59th out of the 100 most cited psychologists of the twentieth century. Ekman conducted seminal research on the specific biological correlations of specific emotions, attempting to demonstrate the universality and discreteness of emotions in a Darwinian approach.

The University of California, San Francisco (UCSF) is a public land-grant research university in San Francisco, California. It is part of the University of California system and is dedicated entirely to health science and life science. It conducts research and teaching in medical and biological sciences.