Longitudinal Imaging of visuaL discrimination and Anxiety in Children

About This Grant

PROJECT ABSTRACT. Rates of anxiety disorders in childhood are increasing and anxiety in childhood often predates other diagnoses. Early identification of trait-based markers associated with anxiety disorder risk, and their neural correlates, is needed to develop childhood interventions that reduce later illness burden in adolescence and adulthood. High trait anxiety is one such behavioral marker that is present in children and is stable over the lifetime. High trait anxiety is characterized by misattribution of threat, such that nonthreatening stimuli are perceived as threatening. Given the developmental importance of social stimuli, faces are a particularly salient source of potential threat in those with high trait anxiety. Indeed, anxious adults tend to perceive threatening emotional expressions at a lower intensity, misattribute threat to neutral expressions, and perceive novel faces as threatening. While threat misattribution in anxiety disorders is often thought to involve reduced prefrontal regulation of limbic regions such as the amygdala, this model alone cannot account for differences in visual discrimination in anxiety, which are present at an early latency following stimulus onset and associated with differences in visual cortical networks. For example, in anxious adults, threat misattribution is associated with altered function of the ventral visual stream and limbic regions, particularly the fusiform gyrus and the amygdala. However, the function of this network and its relationship to anxiety has not been studied developmentally. Given the earlier development of visual cortices relative to prefrontal cortices, visual- limbic networks also likely play a role in high trait anxiety and anxiety disorder risk. Therefore, understanding the development of ventral visual stream regions associated with threat misattribution offers a potential novel target for early intervention. This longitudinal functional magnetic resonance imaging (fMRI) study seeks to characterize the development of the neurofunctional correlates of social threat perception in children ranging in trait anxiety. Children ages 8-12 (n=120) will be scanned, with a subset (n=60, ages 8 to 10 at baseline) scanned a second time two years later. We will collect measures of mood and anxiety symptoms at 3-month intervals following the baseline visit for all participants. The aims of this study are to assess the function of social threat perceptual networks in high trait anxiety. Specifically, we aim to understand the neural correlates of face identity discrimination (novel vs. familiar) and visual discrimination of subtle emotional expressions in children with high trait anxiety using a series of fMRI tasks. We also will explore the development of these circuits over time, and the predictive utility of the function of these regions for understanding the later development of anxiety symptoms and prefrontal regulation of the amygdala in anxiety.