Cortical Modulation of Chronic Pain

描述（由申请人提供）：本研究项目的长期目标是更好地了解针对慢性疼痛的皮质调节治疗的作用机制。有证据表明，大脑并不是痛苦（伤害性）信息的被动接受者，而是在许多层面（包括皮层层面）积极地处理和调节这些信息。初步证据表明，一些针对皮层活动的干预措施可能会减少疼痛体验，因为它们会使慢波（α）皮层活动相对增加，而快波（β）皮层活动相对减少，尽管这些对皮层活动的假设影响尚未得到直接测试。拟议的研究将测试和比较三种创新的神经调节方法（神经反馈、自我催眠训练和经颅直流电刺激）对疼痛强度和脑皮质活动的影响，如脑电图索引，在脊髓损伤和难治性慢性神经性疼痛（n=25）或肌肉骨骼（n=25）患者的样本中。50名研究参与者将接受所有三种积极治疗的单一疗程，安慰剂（假）经颅直流电刺激干预和冥想干预。治疗阶段将至少间隔一周，脑电图评估的皮质活动和疼痛强度将在每次治疗前后进行评估。分析将验证以下假设：(1)每种积极治疗比对照治疗更能减少感知疼痛，(2)每种积极治疗增加相对α波和减少相对β波脑电图评估的皮层活动，(3)积极治疗对疼痛的影响是通过它们对皮层活动的影响来调节的。研究结果将使我们了解三种被认为通过调节皮质活动来减轻疼痛的方法的相对效果。这些数据还将帮助我们了解哪些治疗方法值得对慢性疼痛的治疗进行进一步的研究，以及使用脑电图评估皮层活动作为理解和测量这些治疗方法和其他治疗方法效果的潜在效用。最终，来自本研究的信息可能有助于开发和测试更有效的治疗难治性慢性疼痛的干预措施。由于这些原因，该提案与R21资助机制的目标是一致的。也就是说，它是一项评估“……一个新的研究领域或一个新的实验系统的可行性，有可能加强与健康相关的研究。”（国立卫生研究院，2008年）。公共卫生相关性：慢性疼痛是一个重大的公共卫生问题，许多人患有严重的慢性疼痛，目前可用的治疗方法无法充分控制。我们现在知道慢性疼痛可以通过改变大脑处理疼痛信息的方式来治疗。这个研究项目将帮助我们更好地了解这些治疗对大脑活动的影响，这些信息将有助于指导我们开发新的有效治疗慢性疼痛的方法。

DESCRIPTION (provided by applicant): The long-term objective of this research program is to better understand the mechanisms of action of treatments that target the cortical modulation of chronic pain. Evidence indicates that the brain is not a passive recipient of painful (nociceptive) information, but actively processes and modulates that information at many levels, including at the level of the cortex. Preliminary evidence suggests that a number of interventions that target cortical activity may reduce pain experience because they produce relative increases in slower wave (alpha) cortical activity and relative decreases in faster wave (beta) cortical activity, although these hypothesized effects on cortical activity have not yet been directly tested. The proposed study will test and compare the impact of three innovative neuromodulatory approaches (neurofeedback, self-hypnosis training, and transcranial direct current stimulation) on both pain intensity and on cortical brain activity, as indexed by EEG, in a sample of persons with spinal cord injury and refractory chronic neuropathic (n=25) or musculoskeletal (n=25) pain. 50 study participants will be given a single session of all three active treatments, a placebo (sham) transcranial direct current stimulation intervention, and a meditation intervention. The treatment sessions will be separated by at least one week, and both EEG-assessed cortical activity and pain intensity will be assessed before and after each session. Analyses will test the hypotheses that: (1) each active treatment reduces perceived pain more than the control treatments, (2) each active treatment increases relative alpha wave and decreases relative beta wave EEG-assessed cortical activity, and (3) the effects of the active treatments on pain are mediated by their impact on cortical activity. The results from study will allow us to understand the relative effects of three procedures that are thought to decrease pain by modulating cortical activity. The data will also help us understand which of these procedures warrant further investigation for the management of chronic pain, and the potential utility of using EEG-assessed cortical activity as a means of understanding and measuring the effects of these and other treatments. Ultimately, the information from this study could contribute to the development and testing of more effective interventions for the management of refractory chronic pain. For these reasons, the proposal is consistent with the goals of the R21 funding mechanism. That is, it is a study that assesses "...the feasibility of a novel area of investigation or a new experimental system that has the potential to enhance health-related research." (National Institutes of Health, 2008). PUBLIC HEALTH RELEVANCE: Chronic pain is a significant public health problem, and many people suffer from severe chronic pain that cannot be adequately managed with the treatments that are currently available. We now understand that chronic pain can be influenced by treatments that alter how the brain processes pain information. This research program will help us better understand the effects of these treatments on brain activity, and this information will help guide us in the development of new effective treatments for chronic pain.