Smiling to the Familiar and Unfamiliar (image) University of California - San Diego Caption Subjects smiled more to the familiar in a sad mood and more to the unfamiliar in a happy mood. Credit Courtesy Piotr Winkielman, UC San Diego. Usage Restrictions With credit. 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.