Childhood Stress is Associated with Enhanced Fear Acquisition and Overgeneralization of Fear in a Fear-Potentiated Startle Paradigm

Research has shown that childhood maltreatment is associated with increased risk for trauma- and stressor-related disorders in adulthood. This increased risk might be caused by maltreatment-induced changes in the neural circuitry underlying fear learning, which results in pathological responses to adulthood trauma. To test this hypothesis, we assessed whether childhood maltreatment was associated with altered fear learning and fear generalization in adults. Seventy-four undergraduate students learned to associate a geometrical shape with an aversive stimulus in a fear-potentiated startle paradigm. The next day, participants were tested for their fear generalization by measuring their fear responses to a variety of stimuli that were similar to, but different from, the shape observed on Day 1. Childhood maltreatment was quantified using the Childhood Trauma Questionnaire, and participants were divided into high and low childhood maltreatment groups based on methodology employed in previous work. Results revealed that participants with high childhood maltreatment exhibited stronger fear learning and greater fear generalization than participants with low childhood maltreatment. These findings suggest that exposure to childhood stress could result in greater fear learning and an overgeneralization of fear, which could explain the link between childhood maltreatment and increased risk for certain psychological disorders in adulthood.