Metzger Linda J, Clark C Richard, McFarlane Alexander C, Veltmeyer Melinda D, Lasko Natasha B, Paige Stephen R, Pitman Roger K, Orr Scott P
Veterans Affairs Medical Center, Manchester, New Hampshire 03104, USA.
Psychophysiology. 2009 Jan;46(1):172-8. doi: 10.1111/j.1469-8986.2008.00720.x. Epub 2008 Sep 16.
Studies have demonstrated ERP abnormalities related to concentration difficulties in post-traumatic stress disorder (PTSD). We used an identical-twin, case-control design to investigate whether these abnormalities reflect pre-trauma vulnerability or the acquired consequence of PTSD. Vietnam combat veterans and their non-combat-exposed, identical twins completed a three-tone oddball task. Veterans with PTSD had delayed target N2 latencies compared to veterans without PTSD. In a small nonmedicated, nonsmoking subsample, veterans with PTSD also had significantly diminished target P3b amplitudes. A mixed-model, random-effects analysis on the nonmedicated, nonsmoking subsample that included the combat-unexposed co-twins showed a significant Diagnosis x Combat Exposure interaction for target P3b amplitude. Results replicate increased N2 latency and diminished P3b amplitude in PTSD and suggest that diminished P3b amplitude is an acquired condition in PTSD.
研究表明，创伤后应激障碍（PTSD）中与注意力集中困难相关的事件相关电位（ERP）异常。我们采用同卵双胞胎病例对照设计，以研究这些异常是反映创伤前易感性还是PTSD的后天结果。越战退伍军人及其未接触过战斗的同卵双胞胎完成了一项三音oddball任务。与无PTSD的退伍军人相比，患有PTSD的退伍军人的目标N2潜伏期延迟。在一个未用药、不吸烟的小亚组中，患有PTSD的退伍军人的目标P3b波幅也显著降低。对包括未接触战斗的双胞胎在内的未用药、不吸烟亚组进行的混合模型随机效应分析显示，目标P3b波幅存在显著的诊断×战斗暴露交互作用。结果重复了PTSD中N2潜伏期延长和P3b波幅降低的情况，并表明P3b波幅降低是PTSD中的一种后天状况。
