Department of Psychology, The University of Tulsa, Tulsa OK.
Department of Psychology, The University of Tulsa, Tulsa OK.
J Pain. 2019 Sep;20(9):1027-1039. doi: 10.1016/j.jpain.2019.02.012. Epub 2019 Feb 27.
Sexual assault (SA) is associated with an increased risk of chronic pain, but the mechanisms for this relationship are poorly understood. To explore whether disrupted descending inhibition is involved, this study used a conditioned pain modulation task to study the inhibition of pain and the nociceptive flexion reflex (NFR; a correlate of spinal nociception) in 32 pain-free SA survivors. This group was compared with 32 pain-free, trauma-exposed persons without SA and a group of 40 pain-free persons who reported no trauma exposure. Conditioned pain modulation was assessed from painful electric stimulations (test stimulus) delivered to the ankle before, during, and after participants submerged their hand in painful 10°C water (conditioning stimulus). Pain ratings and NFR were assessed in response to test stimuli. All groups demonstrated significant inhibition of pain during conditioned pain modulation. However, only the no trauma exposure group demonstrated significant inhibition of NFR. The persons without SA group showed no inhibition of NFR, whereas the SA group showed significant facilitation of the NFR. These findings suggest that trauma exposure may impair inhibitory cerebrospinal circuits, but that SA may specifically promote facilitation of spinal nociception. Perspective: This study suggests that trauma exposure disrupts the cerebrospinal inhibition of spinal nociception, but that exposure to SA further promotes chronic pain risk by facilitating spinal nociception. This finding help may help to elucidate the pain risk mechanisms in trauma survivors.
性侵犯(SA)与慢性疼痛的风险增加有关,但这种关系的机制尚不清楚。为了探讨是否存在下行抑制中断的情况,本研究使用条件性疼痛调制任务来研究 32 名无疼痛的 SA 幸存者的疼痛抑制和伤害性屈肌反射(NFR;与脊髓伤害性感受相关)。将该组与 32 名无疼痛、无创伤暴露的创伤暴露者和 40 名无疼痛、无创伤暴露的创伤暴露者进行比较。在参与者将手浸入疼痛的 10°C 水中(条件刺激)之前、期间和之后,对疼痛的电刺激(测试刺激)进行条件性疼痛调制评估。在测试刺激下评估疼痛评分和 NFR。所有组在条件性疼痛调制期间均表现出明显的疼痛抑制。然而,只有无创伤暴露组表现出 NFR 的明显抑制。无 SA 组的 NFR 无抑制,而 SA 组的 NFR 明显促进。这些发现表明,创伤暴露可能会损害脊髓抑制性脑回路,但 SA 可能会通过促进脊髓伤害感受来特异性地增加慢性疼痛的风险。观点:本研究表明,创伤暴露会破坏脊髓抑制性疼痛的脊髓抑制,但暴露于 SA 会通过促进脊髓伤害感受进一步增加慢性疼痛的风险。这一发现有助于阐明创伤幸存者的疼痛风险机制。
Eur J Pain. 2017-10
Biol Psychol. 2016-12