Threat-related gamma as a mechanism linking childhood maltreatment and adult anxiety

Abstract Hypervigilance to threats has been a proposed latent vulnerability to developing anxiety disorders in individuals who experienced childhood maltreatment (CM). While the neural mechanisms are increasingly being understood, their ecological and clinical validity remain limited. To address this issue, the current study aimed to elucidate novel mechanisms by combining the threat imminence continuum framework with computer-based virtual reality to examine electrophysiological indices of high (right posterior theta, 4–8 Hz) and low (posterior midline gamma, 30–60 Hz) imminence threats. University students ( N = 84, aged 18–34) self-reported anxiety symptoms by using the Beck Anxiety Inventory and State-Trait Anxiety Inventory, while CM history was indexed with the Childhood Trauma Questionnaire. EEG was collected while participants engaged in the Risk-Reward Interaction task, where right posterior theta and posterior midline gamma power were extracted as oscillatory markers. Structural equation modeling assessed the mediating effect of marker activity on the relationship between CM and anxiety. Posterior midline gamma power fully mediated the association between CM and anxiety (β = 0.1, p < .05), such that greater CM severity predicted increased gamma activity, in turn predicting increased anxiety. Right posterior theta power was not related to either anxiety or CM. Distortions of the threat imminence continuum, observed in posterior midline gamma activity, is a novel mechanism that may reflect a latent vulnerability to anxiety. These findings provide a new perspective with which to understand the emergence of CM-related psychopathology and has the potential to inform interventions to build resilience in this vulnerable population.