PROSPECTIVE PSYCHOPHYSIOLOGIC STUDY OF RISK FOR PTSD

目前还没有被普遍接受的方法来前瞻性地识别创伤后应激障碍（PTSD）风险个体。然而，一些个体差异变量显示出作为创伤前危险因素的希望。最近来自PI的差异条件反射研究的发现表明，创伤后应激障碍患者的条件性皮肤电导反应比非创伤后应激障碍、创伤暴露对照组患者的条件性皮肤电导反应获得得更强烈，消退得更慢，也就是说，创伤后应激障碍患者更“可条件化”。考虑到许多创伤后应激障碍的症状可以被定义为条件反应（CRs），那么那些一开始就更容易获得条件反应的人更有可能患上这种疾病，这是合理的。该项目将研究一套有前景的创伤前心理生理学、内分泌学和心理测量方法，以预测消防员/EMT和警察新兵暴露于创伤性事件后PTSD的发生和严重程度。假设选择的创伤前测量可以预测创伤事件后的创伤后应激障碍。在接受招募培训之前，受试者将接受一系列心理测量问卷。巴甫洛夫微分条件反射程序，将有色圆圈与轻度厌恶的UCS配对。还将测量其他对测量创伤后应激障碍有用的心理生理学测试，例如惊吓反应和低剂量（0.5 mg）地塞米松对唾液皮质醇的抑制。在创伤前评估后，将密切跟踪受试者是否发生符合DSM-IV PTSD a .1标准的创伤性事件。事件发生三个月后，受创伤者将返回医院接受PTSD的心理诊断、心理测量和心理生理评估。Logistic和多元回归技术将用于检验心理生理学、内分泌学和心理测量预测指标与PTSD分类和持续结果指标之间的关系。

There are no generally accepted methods for prospectively identifying individuals at risk for post-traumatic stress disorder (PTSD) after a traumatic event. However, several individual difference variables show promise as pre-trauma risk factors. Recent findings from the PI's differential conditioning study indicate that a conditioned skin conductance response is acquired more strongly and extinguishes more slowly in PTSD than in non-PTSD, trauma-exposed control subjects, i.e., that PTSD subjects are more "conditionable." Given that many PTSD symptoms may be conceptualized as conditioned responses (CRs), it is plausible that individuals who are more prone to acquire CRs in the first place would be more likely to develop this disorder. The proposed project will examine a promising set of pre-trauma psychophysiologic, endocrinologic, and psychometric measures for their ability to predict the occurrence and severity of PTSD following exposure to traumatic events in firefighter/EMT and police recruits. It is hypothesized that the selected pre-trauma measures will predict PTSD following an index traumatic event. Prior to receiving their recruitment training, subjects will undergo a battery of psychometric questionnaires. A Pavlovian differential conditioning procedure which pairs colored circles with a mildly aversive UCS will be administered. Other psychophysiologic tests found useful in measuring PTSD, e.g., startle response, and suppression of salivary cortisol by a low (0.5 mg) dose of dexamethasone, will also be measured. After the pre-trauma assessment, subjects will be closely followed for the occurrence of a traumatic event that meets the DSM-IV PTSD A.1 criterion. Three months after such an event, the trauma-exposed subject will return for psychodiagnostic, psychometric, and psychophysiologic assessment of PTSD. Logistic and multiple regression techniques will be used to examine the relationship between psychophysiologic, endocrinologic, and psychometric predictor measures and categorical and continuous PTSD outcome measures.