Department of Psychology,Tufts University,Medford, MA,USA.
Department of Epidemiology,Harvard T. H. Chan School of Public Health,Boston, MA,USA.
Psychol Med. 2018 May;48(7):1128-1138. doi: 10.1017/S003329171700263X. Epub 2017 Sep 12.
Previous research has shown relatively diminished medial prefrontal cortex activation and heightened psychophysiological responses during the recollection of personal events in post-traumatic stress disorder (PTSD), but the origin of these abnormalities is unknown. Twin studies provide the opportunity to determine whether such abnormalities reflect familial vulnerabilities, result from trauma exposure, or are acquired characteristics of PTSD.
In this case-control twin study, 26 male identical twin pairs (12 PTSD; 14 non-PTSD) discordant for PTSD and combat exposure recalled and imagined trauma-unrelated stressful and neutral life events using a standard script-driven imagery paradigm during functional magnetic resonance imaging and concurrent skin conductance measurement.
Diminished activation in the medial prefrontal cortex during Stressful v. Neutral script-driven imagery was observed in the individuals with PTSD, relative to other groups.
Diminished medial prefrontal cortex activation during Stressful v. Neutral script-driven imagery may be an acquired characteristic of PTSD. If replicated, this finding could be used prospectively to inform diagnosis and the assessment of treatment response.
先前的研究表明,创伤后应激障碍(PTSD)患者在回忆个人事件时,内侧前额叶皮层的激活程度相对较低,心理生理反应增强,但这些异常的起源尚不清楚。双胞胎研究提供了一个机会,可以确定这些异常是否反映了家族易感性,是创伤暴露的结果,还是 PTSD 的获得性特征。
在这项病例对照双胞胎研究中,26 对男性同卵双胞胎(12 对 PTSD;14 对非 PTSD)对 PTSD 和战斗暴露存在分歧,并在功能磁共振成像和同时进行的皮肤电导率测量期间,使用标准脚本驱动的意象范式回忆和想象与创伤无关的压力和中性生活事件。
与其他组相比,PTSD 患者在处理压力脚本与中性脚本时,内侧前额叶皮层的激活程度降低。
在处理压力脚本与中性脚本时内侧前额叶皮层的激活程度降低可能是 PTSD 的获得性特征。如果得到复制,这一发现可以前瞻性地用于告知诊断和治疗反应的评估。