Adults with autism spectrum disorders (ASD) represent a poorly understood and underserved population. Co-occurring depression is a leading form of clinical impairment for this group, yet few studies have explored potential underlying mechanisms of and intervention for depression in ASD. There is a significant clinical need to translate methods from depression research to ASD, with the ultimate goal of developing effective assessment and intervention for this specific comorbidity. The goal of this training plan is to position the PI as an independent investigator and translational bridge between ASD and depression research. The PI's immediate goals are (1) to develop expertise in the area of measurement and analysis of behavioral, cognitive, and affective features of depression, including specific psychophysio- logical methods; and (2) to acquire specific training in the adaptation of these research methods for use in persons with ASD. To meet these goals, the PI has proposed a career development plan that integrates mentored research experience, advanced coursework, and active involvement in an institutional environment strongly conducive to cutting-edge autism and depression research. This research proposal explores possible mechanisms by which ASD confers increased risk for depression. The specific aims are to: (1) to compare adults with ASD, depression, and typical development on measures of social motivation (eye-tracking), modulation of affective responses (electrophysiology), perseverative thought (psychometric measures of rumination and insistence on sameness), and anxiety; and (2) to investigate individual differences in these depression risk factors and their impact on dail experience among adults with ASD. Participants with ASD who have high versus low levels of rumination / Insistence on Sameness will be compared on social motivation, affect modulation, and anxiety, as well as on real-time measures of social engagement and depressive symptoms collected daily via experience sampling. Training in depression theory and research methods will augment the PI's existing training in measurement and phenotyping in ASD. Most importantly, it will accelerate her career as a successful independent investigator well equipped to design and evaluate theoretically grounded interventions for depression within the ASD community. As such, this research and training plan are well-aligned with NIMH goals to study both causal mechanisms and intervention for a clinically significant health problem in a special population.