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皮质调节的治疗的作用机制。有证据表明，大脑不是疼痛（伤害性）信息的被动接受者，而是在许多层面上积极处理和调节这些信息，包括在皮层水平。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，而使快波（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）对疼痛强度和皮层脑活动的影响，如EEG所示，在脊髓损伤和难治性慢性神经性疼痛（n=25）或肌肉骨骼疼痛（n=25）的样本中。50名研究参与者将接受所有三种活性治疗的单次治疗，安慰剂（假）经颅直流电刺激干预和冥想干预。治疗疗程将间隔至少一周，并且将在每次疗程前后评估EEG评估的皮质活动和疼痛强度。分析将检验以下假设：（1）每种活性治疗比对照治疗更能降低感知疼痛，（2）每种活性治疗增加相对α波并降低相对β波EEG评估的皮质活动，以及（3）活性治疗对疼痛的影响是通过其对皮质活动的影响介导的。研究结果将使我们了解三种程序的相对效果，这些程序被认为是通过调节皮层活动来减少疼痛。这些数据还将帮助我们了解这些程序中哪些程序需要进一步调查慢性疼痛的管理，以及使用EEG评估的皮层活动作为理解和测量这些和其他治疗效果的手段的潜在效用。最终，这项研究的信息可能有助于开发和测试更有效的干预措施来管理难治性慢性疼痛。出于这些原因，该提案符合21世纪责任供资机制的目标。也就是说，这是一项评估“...一个新的研究领域或一个新的实验系统的可行性，有可能加强与健康有关的研究。”（美国国立卫生研究院，2008年）。公共卫生相关性：慢性疼痛是一个重要的公共卫生问题，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管理。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影响。这项研究计划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.