Biomarkers are important as they can be used to better define the heterogeneity of ASD, including markers that can be used to predict outcomes and improve measurement of treatment response. The PHOEBE study, originally funded by the Simons Foundation, developed biomarkers in order to achieve these goals. The biomarkers in this study are physiologic driven responses to social information, social interactions, and frustration. The study utilized automated eye tracking and measures of physiologic regulation in response to stressors and challenge.