Abstract
BACKGROUND: Negative reactivity (NR) and behavioral inhibition (BI), temperamental traits characterized by novelty-evoked distress and avoidance, respectively, represent risk markers for anxiety. However, not all infants with NR and BI develop anxiety. Pathways from infant temperament to anxiety remain underspecified. This study tests the hypothesis that heightened neural sensitivity to unexpected sensory stimuli in infancy moderates risk for anxiety. METHODS: Data from the Temperament Over Time Study (N = 291) were utilized. Infants completed laboratory-based assessments of NR at 4 months (M) and BI at 2 to 3 years. BI was also assessed using parent report. At 9M and 36M, electroencephalography was collected during a passive 3-stimulus auditory oddball task, and the mismatch response (MMR) and novelty P3 were quantified. Adolescent anxiety was measured using parent- and self-reports and clinical interviews at 13 and 15 years. Structural equational modeling analyses were applied to examine whether infants' MMR or novelty P3 at 9M and 36M modulate relationships between NR, BI, and adolescent anxiety. RESULTS: The MMR at 9M moderated the relationship between NR and BI, and the MMR at 36M moderated the relationship between BI and 13-year anxiety. In both cases, a more negative MMR was associated with elevated risk. This association was not present for attention problems or externalizing outcomes. Additional exploratory analyses showed that the novelty P3 mediated pathways from NR to social anxiety. CONCLUSIONS: Individual differences in the infant's neural response to unexpected stimuli relate to temperamental risk for anxiety.