Trauma exposure is prevalent, associated with multiple forms of psychopathology, and thought to alter the neurobiological substrates of threat processing. The late positive potential (LPP) is an event-related potential (ERP) that may be a clinically useful probe of the neurobiology of threat processing. Despite evidence that combat-exposed veterans exhibit aberrant threat modulation of the LPP, no studies to date have tested the psychometric properties of the LPP in combat trauma-exposed, symptomatic veterans. The primary aim of the current study was to evaluate the reliability (internal consistency, retest reliability) and convergent validity of LPP modulation by threatening faces and scenes in two common tasks among combat-exposed veterans. Participants included 82 combat-exposed veterans who completed face-matching and emotion regulation tasks during EEG recording at baseline and twelve weeks. Internal consistencies of the early LPP time windows (<1000 ms) were acceptable in both tasks, whereas they were poor in late time windows (>1000 ms). Twelve-week retest reliabilities were fair for the early window LPPs to threatening scenes and fear faces, as well as in the late time window for fear faces. Reliabilities were better for individual condition compared to difference scores. Finally, LPPs modulated by threatening scenes and faces were unrelated. Together, these results suggest that the LPPs to threatening scenes and faces reflect distinct forms of threat processing in combat-exposed veterans, and their reliabilities for the early window indicate potential clinical utility in this population.

创伤暴露很普遍，与多种形式的精神病理学有关，并被认为会改变威胁处理的神经生物学基础。晚期阳性电位 (LPP) 是一种事件相关电位 (ERP)，可能是威胁处理神经生物学的临床有用探针。尽管有证据表明，暴露在战斗中的退伍军人表现出 LPP 的异常威胁调制，但迄今为止还没有研究在暴露于战斗创伤、有症状的退伍军人中测试 LPP 的心理测量特性。本研究的主要目的是评估 LPP 调制的可靠性（内部一致性、重测可靠性）和收敛效度，通过在战斗中暴露的退伍军人的两个常见任务中威胁面孔和场景。参与者包括 82 名经历过战斗的退伍军人，他们在基线和 12 周的脑电图记录期间完成了面部匹配和情绪调节任务。早期 LPP 时间窗口 (<1000 ms) 的内部一致性在两个任务中都是可以接受的，而在后期时间窗口 (>1000 ms) 中它们很差。对于威胁场景和恐惧面孔的早期窗口 LPP 以及恐惧面孔的后期窗口，12 周的重新测试可靠性是公平的。与差异分数相比，个体条件的可靠性更好。最后，由威胁场景和面孔调制的 LPP 是无关的。总之，这些结果表明，LPP 对威胁场景和面孔的反应反映了暴露在战斗中的退伍军人的不同形式的威胁处理，