Graded Affective-Neural-Behavioral Vulnerability in Trait Anxiety under Frustrative Reward Outcome: ERP Evidence.

INTRODUCTION: Reward outcome processing has received increasing attention in trait anxiety, yet existing findings remain inconsistent. We tested a conditional-vulnerability account, proposing that reward outcome processing vulnerability in trait anxiety may not reflect a stable generalized deficit, but may dynamically emerge when emotional and motivational demands on the reward system increase. Using graded frustrative non-reward as an affective-motivational challenge, we examined whether this vulnerability unfolds across dissociable affective, neural, and behavioral levels. METHOD: Event-related potentials (ERPs) were recorded from 30 high-trait-anxiety (HTA) and 30 low-trait-anxiety (LTA) participants during a modified frustrative non-reward task. The measures included self-reported frustration, accuracy, reaction time, and ERP indices of reward outcome processing, including P3 and reward positivity (RewP). RESULTS: The HTA group reported higher frustration and showed lower overall accuracy than the LTA group. Reaction times did not differ between groups under low- or mid-frustration, but the HTA group responded faster under high-frustration. ERP results showed that the HTA group exhibited greater reward and loss RewP changes as frustration increased. Difference RewP further showed an increase from mid- to high-frustration in the HTA group, whereas this pattern was not observed in the LTA group. DISCUSSION: These findings support a graded affective-neural-behavioral vulnerability profile of reward outcome processing in trait anxiety, with vulnerability evident across affective, neural, and behavioral indicators as frustrative challenge increases. Thus, trait-anxiety-related vulnerability in reward outcome processing may be understood as graded and context-sensitive rather than stable and generalized, providing a framework for examining how trait anxiety shapes reward outcome processing.