Project Summary The adult and child clinical literature suggests that individuals who are clinically anxious or have high levels of trait anxiety show attention biases to threat. In addition, researchers can exacerbate or ameliorate levels of anxious thought and behavior by experimentally manipulating attention biases in the lab. This has led researchers to argue that attention biases to threat may cause anxiety. These studies are an important and useful proof of concept for the role of attention in the emergence of anxiety. However, as with much of the literature, these studies rely on computer-based tasks that present individuals with static emotion faces and words. Biases are inferred from patterns of behavioral reaction times (RTs) or eye-tracking to the stimuli. These data, while informative, have relatively low levels of ecological validity, as the stimuli are uni- dimensional and unable to support potential interaction. In addition, these tasks tap into orienting to preselected stimuli, rather than threat-related attention selection. However, underlying theory suggests that attention is associated with social withdrawal/anxiety specifically because social and threatening aspects of the environment are unpredictable, multi-dimensional, and require flexibility from the child. Thus, we know little, if anything, regarding how attention bias in vivo may be associated with early social behavior. We need methodologies that can more closely capture the child's experience of his or her environment (social and non-social) and are child-focused and child-directed. The current proposal addresses these gaps by (1) testing an innovative mobile eye-tracking system in (2) young children at temperamental risk for anxiety as they (3) engage in both sedentary and interactive attention to threat paradigms. We will incorporate continuous measurements of eye gaze during episodes from the Laboratory Temperament Assessment Battery (Lab-TAB) designed to elicit fearful behavior towards putative social and non-social threats. A social dyad episode will be used to examine attention processes deployed during joint play. We focus on 4 to 6-year- old children ? an age period preceding the onset of anxiety disorders, but during which social withdrawal is more apparent for temperamentally fearful children. As such, we will examine if children varying in behavioral inhibition (BI), our strongest temperamental predictor of anxiety, differ in threat-related attention on stationary and mobile eye tracking tasks versus non-BI peers. Finally, we will look to see if either sedentary or mobile attention to threat data helps better predict the association between BI and anxiety and social withdrawal. This line of research reflects the focus in the Research Domain Criteria on integrating multilevel mechanisms by examining response to potential threat (negative valence systems), attention patterns (cognitive systems) and early patterns of affect across varying socioemotional contexts (negative valence systems and social processes). We also go to the heart of NIMH's Objective 2, by characterizing markers of behavioral development in order to identify clinically useful indicators of change across illness trajectories.