Alterations in fear learning as a mechanism linking childhood exposure to violence with PTSD symptoms: a longitudinal study.

Abstract

Background: Fear learning is a core component of conceptual models of how adverse experiences may influence psychopathology. Specifically, existing theories posit that childhood experiences involving childhood trauma are associated with altered fear learning processes, while experiences involving deprivation are not. Several studies have found altered fear acquisition in youth exposed to trauma, but not deprivation, although the specific patterns have varied across studies. The present study utilizes a longitudinal sample of children with variability in adversity experiences to examine associations among childhood trauma, fear learning, and psychopathology in youth.

Methods: The sample includes 170 youths aged 10-13 years (M = 11.56, s.d. = 0.47, 48.24% female). Children completed a fear conditioning task while skin conductance responses (SCR) were obtained, which included both acquisition and extinction. Childhood trauma and deprivation severity were measured using both parent and youth report. Symptoms of anxiety, externalizing problems, and post-traumatic stress disorder (PTSD) were assessed at baseline and again two-years later.

Results: Greater trauma-related experiences were associated with greater SCR to the threat cue (CS+) relative to the safety cue (CS-) in early fear acquisition, controlling for deprivation, age, and sex. Deprivation was unrelated to fear learning. Greater SCR to the threat cue during early acquisition was associated with increased PTSD symptoms over time controlling for baseline symptoms and mediated the relationship between trauma and prospective changes in PTSD symptoms.

Conclusions: Childhood trauma is associated with altered fear learning in youth, which may be one mechanism linking exposure to violence with the emergence of PTSD symptoms in adolescence.