Research Training Group (RTG) 2175 perception in Context and Its Neural Basis, Ludwig-Maximilians-University Munich, 82152 Planegg, Germany; Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, 82152 Planegg, Germany.
Research Training Group (RTG) 2175 perception in Context and Its Neural Basis, Ludwig-Maximilians-University Munich, 82152 Planegg, Germany; Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, 82152 Planegg, Germany; Department of Neurology, University Hospital Großhadern, Ludwig-Maximilians-University Munich, 81377 Munich, Germany.
Neuroimage. 2023 Dec 1;283:120432. doi: 10.1016/j.neuroimage.2023.120432. Epub 2023 Oct 30.
The human body has the ability to influence its sensation of pain by modifying the transfer of nociceptive information at the spinal level. This modulation, known as descending pain inhibition, is known to originate supraspinally and can be activated by a variety of ways including positive mental imagery. However, its exact mechanisms remain unknown. We investigated, using a longitudinal fMRI design, the brain activity leading up and in response to painful electrical stimulation when applying positive mental imagery before and after undergoing a previously established RIII-feedback paradigm. Time course analysis of the time preceding painful stimulation shows increased haemodynamic activity during the application of the strategy in the PFC, ACC, insula, thalamus, and hypothalamus. Time course analysis of the reaction to painful stimulation shows decreased reaction post-training in brainstem and thalamus, as well as the insula and dorsolateral PFC. Our work suggests that feedback training increases activity in areas involved in pain inhibition, while simultaneously decreasing the reaction to painful stimuli in brain areas related to pain processing, which points to an activation of decreased spinal nociception. We further suggest that the insula and the thalamus may play a more important role in pain modulation than previously assumed.
人体具有在脊髓水平改变伤害性信息传递从而影响疼痛感知的能力。这种调制被称为下行性疼痛抑制，已知起源于脊髓以上，可以通过多种方式激活，包括积极的心理意象。然而，其确切的机制仍不清楚。我们使用纵向 fMRI 设计，在进行先前建立的 RIII-反馈范式前后，在施加积极的心理意象时，研究了导致疼痛性电刺激的脑活动。在疼痛刺激前的时间进程分析中，在 PFC、ACC、岛叶、丘脑和下丘脑，在应用该策略时显示出更高的血液动力学活动。对疼痛刺激反应的时间进程分析表明，在训练后，脑干和丘脑，以及岛叶和背外侧 PFC 的反应减少。我们的工作表明，反馈训练增加了参与疼痛抑制的区域的活动，同时减少了与疼痛处理相关的脑区对疼痛刺激的反应，这表明脊髓伤害性感受的降低得到了激活。我们进一步表明，与之前的假设相比，岛叶和丘脑可能在疼痛调制中发挥更重要的作用。
