Familiar vs. Unfamiliar Faces (IMAGE) University of California - San Diego Caption Study participants were familiarized with faces surreptitiously, as background images on a supposed memory task. Later, when asked to pick between two faces showing the same objective level of emotion -- 25 percent happy, let's say -- participants said the familiar face looked happier than the unfamiliar. Credit Figure courtesy Evan Carr Usage Restrictions With coverage of this study only License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.