Imaging the Cognitive Modulation of Pain in Fibromyalgia

描述：纤维肌痛（FM）是一种致残障碍，其特征是广泛的医学上无法解释的疼痛。FM的诊断伴随着有限的预后，不到一半的FM患者经历足够的疼痛缓解。FM患者往往得不到治疗，导致更严重的功能残疾和更多的医疗保健利用。研究旨在揭示FM中不明原因疼痛的机制，以指导潜在的治疗方法，并更好地了解这种疾病的病理生理。在实验室收集的脑成像数据显示，fMRI对非痛觉和痛觉热的反应增强，并支持了中枢伤害性过程异常维持FM疼痛的新观点。然而，预期和注意力等认知过程也会影响大脑反应，并且已知会影响慢性疼痛的结果。广泛的目标是进一步了解不明原因的肌肉骨骼疼痛在FM。功能磁共振成像（fMRI）是一种客观测量伤害性加工的方法，对感觉和认知操作很敏感。因此，该项目的具体目的是：(1)通过比较FM患者和类风湿关节炎患者（RA），确定增强的中央处理是FM独有的还是慢性疼痛的结果；(2)确定疼痛预期对FM患者非疼痛刺激fMRI反应的影响；(3)确定疼痛注意对FM患者疼痛刺激中枢加工的影响。为了操纵对疼痛的预期，受试者将被随机分配到疼痛和无疼痛的条件下。为了操纵对疼痛的注意，受试者将在接受疼痛或非疼痛热刺激的同时执行Stroop颜色单词任务。这项研究将在两天内进行。第一天将在模拟核磁共振单元进行疼痛和Stroop表现的心理物理分析。第二天将包括功能性脑成像（fMRI），同时受试者接受非疼痛或疼痛的热刺激并执行Stroop。我们认为FM是一种独特的慢性疼痛疾病，涉及感官刺激的失调处理，并且增强的大脑反应不会受到预期和注意操作的影响。这将是了解FM中无法解释的肌肉疼痛机制的重要的第一步。

DESCRIPTION: Fibromyalgia (FM) is a disabling disorder characterized by widespread medically unexplained pain. A diagnosis of FM is accompanied by a limited prognosis and less than half of all FM patients experience adequate pain relief. FM patients are often left under treated, resulting in greater functional disability and increased health care utilization. Research Aimed at uncovering mechanisms of unexplained pain in FM is needed to guide potential treatment approaches and better understand the pathophysiology of this disorder. Brain imaging data collected in laboratory have demonstrated augmented fMRI responses to both non-painful and painful heat, and support the emerging view that abnormalities in central nociceptive processes act to maintain FM pain. Nevertheless, cognitive processes such as anticipation and attention could also affect brain responses and are known to affect chronic pain outcomes. The broad objectives are to further understanding of unexplained musculoskeletal pain in FM. fMRI is an objective measure of nociceptive processing, sensitive to sensory and cognitive manipulations. Thus, the Specific Aims of the project are to: (1) determine whether augmented central processing is unique to FM or is a consequence of chronic pain by comparing FM patients to rheumatoid arthritis patients (RA); (2) determine the influence of pain anticipation on fMRI responses to non-painful stimuli in FM patients compared to healthy and RA controls, and (3) determine the influence of attention to pain on central processing of painful stimuli in FM patients compared to healthy and RA controls. To manipulate anticipation of pain, subjects will be randomly assigned to pain and no pain conditions. To manipulate attention to pain, subjects will perform the Stroop color word task while receiving either painful or non-painful heat stimuli. The study will be conducted on two separate days. Day one will be conducted in a simulated MRI unit for psychophysical analysis of pain and performance of the Stroop. Day two will consist of functional brain imaging (fMRI) while the subjects receive either non-painful or painful heat stimuli and perform the Stroop. We posit that FM is a unique chronic pain disorder that involves dysregulated processing of sensory stimuli and that augmented brain responses will not be affected by manipulations of anticipation and attention. This will be a first important step towards understanding the mechanisms of unexplained muscle pain in FM.