Translational Neuromodeling Unit, Institute of Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland.
School of Pharmacy, University of Otago, New Zealand.
Pain. 2021 Dec 1;162(12):2933-2944. doi: 10.1097/j.pain.0000000000002327.
Brain biomarkers of pain, including pain-predictive "signatures" based on brain activity, can provide measures of neurophysiological processes and potential targets for interventions. A central issue relates to the specificity of such measures, and understanding their current limits will both advance their development and explore potentially generalizable properties of pain to other states. Here, we used 2 data sets to test the neurologic pain signature (NPS), an established pain neuromarker. In study 1, brain activity was measured using high-field functional magnetic resonance imaging (7T fMRI, N = 40) during 5 to 25 seconds of experimental breathlessness (induced by inspiratory resistive loading), conditioned breathlessness anticipation, and finger opposition. In study 2, we assessed anticipation and breathlessness perception (3T, N = 19) under blinded saline (placebo) and remifentanil administration. The NPS responded to breathlessness, anticipation, and finger opposition, although no direct comparisons with painful events were possible. Local NPS patterns in anterior or midinsula, S2, and dorsal anterior cingulate responded to breathlessness and finger opposition and were reduced by remifentanil. Local NPS responses in the dorsal posterior insula did not respond to any manipulations. Therefore, significant global NPS activity alone is not specific for pain, and we offer insight into the overlap between NPS responses, breathlessness, and somatomotor demand.
脑疼痛生物标志物，包括基于大脑活动的疼痛预测“特征”，可以提供神经生理过程的测量和潜在干预靶点。一个核心问题涉及到这些措施的特异性，了解它们当前的局限性将有助于推进其发展，并探索疼痛在其他状态下可能具有的普遍性。在这里，我们使用了两个数据集来测试神经疼痛特征（NPS），这是一种已建立的疼痛神经标志物。在研究 1 中，使用高场功能磁共振成像（7T fMRI，N = 40）测量了 5 到 25 秒的实验性呼吸困难（通过吸气阻力加载引起）、条件性呼吸困难预期和手指对抗期间的大脑活动。在研究 2 中，我们在盲注盐水（安慰剂）和瑞芬太尼给药下评估了预期和呼吸困难感知（3T，N = 19）。NPS 对呼吸困难、预期和手指对抗有反应，尽管无法与疼痛事件进行直接比较。前岛或中岛、S2 和背侧前扣带回的局部 NPS 模式对呼吸困难和手指对抗有反应，并且被瑞芬太尼减少。后岛背侧的局部 NPS 反应不受任何操作的影响。因此，单独的显著全局 NPS 活动并不特定于疼痛，我们深入了解了 NPS 反应、呼吸困难和躯体需求之间的重叠。
