負向信念預測創傷後壓力症狀之三個月追蹤研究：創傷記憶特性的中介角色

A Three-Month Prospective Investigation of Negative Cognitions in Predicting Posttraumatic Stress Symptoms: The Mediating Role of Traumatic Memory Quality

本研究旨在透過前瞻性研究探討負向信念對PTSD症狀嚴重度之預測效果，並檢驗創傷記憶特性之中介效果。作者依據當前主要的PTSD認知理論提出研究架構，結合負向信念、創傷記憶特性及PTSD進行探討。樣本為61位經歷DSM- IV PTSD準則A事件的大學生，於時間點一（T1）填寫創傷後壓力診斷量表、創傷後認知量表、SCL- 90- R之憂鬱分量表，三個月後（T2）再填寫上述量表與創傷記憶問卷。結果顯示：（1）控制性別、年齡、PTSDT1與憂鬱症狀T1後，負向自我T1與負向世界信念T1可預測PTSD症狀嚴重度T2；（2）負向自我T1與負向世界信念T1可預測再經歷症狀嚴重度T2，負向自我信念T1預測效果較佳；負向世界信念T1可預測迴避／麻木症狀嚴重度T2，然僅達邊緣顯著水準；（3）創傷記憶特性中僅記憶威脅程度T2可預測PTSD症狀嚴重度T2；（4）因徑分析顯示，負向信念T1可直接與間接透過記憶威脅T2中介影響PTSD症狀嚴重度T2。本研究發現負向信念與創傷記憶威脅對PTSD症狀之維持有顯著貢獻，此與晚近主要認知理論對PTSD何以持續之觀點相符。

Recently, several studies have indicated that trauma survivors may adopt an extreme view about dangerousness of the world and lack ability to cope with threat and stress after the trauma, thus raise their risk of chronic PTSD. Other theories have postulated that quality and nature of trauma memories may relate to the presence of pathological stress reactions. The failure to integrate traumatic memories may impart its potential to cause posttraumatic stress disorders. Traumatic memories, as a kind of cognitive representation, appears to be more related to the core symptoms of PTSD (e.g., intrusive symptoms) at psychopathological level. Hence, it may serve as a mediator between posttrauma negative beliefs and subsequent PTSD. By integrating these two lines of research findings, the present study attempted to address a framework that links negative beliefs, traumatic memory, and PTSD and investigate their associations. Participants included 61 college students who had experienced at least one traumatic event that satisfied DSM-IV PTSD criteria A. They were administered the Posttraumatic Diagnostic Scale (PDS), Posttraumatic Cognitions Inventory (PTCI), and Depressive Subscale of Symptom Checklist 90- R (SCL- 90- R) at Time 1 (T1). Modified Traumatic Memory Inventory with the same above- mentioned protocol was given again at follow- up assessment 3 months after the initial assessment (T). Results indicated that 1) PTSD symptoms at T2 could be predicted by negative self and world beliefs but not selfblame thinking at T1, after controlling for gender, age, as well as PTSD and depressive symptoms at T1; 2) Reexperiencing symptoms at T2 could be predicted by negative self and world beliefs at T1, and the predictive effect of negative self belief at T1 was higher than the other beliefs at T1. Avoidance symptoms at T2 could be predicted by negative world beliefs at T1, and the predictive effect of negative world belief at T1 that merely reached marginally significant level was higher than the other beliefs at T1; 3) PTSD symptom at T2 could be accounted for by concurrent overwhelming traumatic memory, after controlling for gender, age, as well as PTSD and depressive symptoms at T1. However, the remaining variables of trauma memory did not account for significant variance; 4) by using path analysis; we found that overwhelming traumatic memory at T2 mediated the relation between negative self and world beliefs at T1 and subsequent PTSD symptoms at T2. Overall, it was demonstrated that posttrauma negative beliefs and traumatic memory quality may contribute to the maintenance of PTSD symptoms. These findings are parallel to recent cognitive theories of PTSD.