Fig. 1

Approach-avoidance conflict model that provided the bases for the current study protocol, aims, and hypotheses. As illustrated, both the fear or avoidance system and the reward/approach system are considered important in eliciting conflict and anxiety. Conflict arbitration requires appropriate balancing of both approach and avoidance drives. In the current protocol, approach and avoidance behaviors are defined by approach-avoidance test (AAT) bias scores; conflict arbitration is defined by reaction time during the approach-avoidance conflict (AAC) trials. For brain responses, we focus on the AAC task and extract percentage signal change (PSC) from a priori regions of interest: (1) approach: left caudate (reward versus no-reward outcome), (2) avoidance: right amygdala (negative versus positive affective outcome), and (3) conflict: right dorsolateral prefrontal cortex (dlPFC; conflict versus nonconflict decisions). Exposure-based therapy was included as a treatment that primarily targets avoidance or threat processes, whereas behavioral activation was included as a treatment that primarily targets approach or reward systems