Anhedonia to Gentle Touch in Fibromyalgia: Normal Sensory Processing but Abnormal Evaluation
Anhedonia to Gentle Touch in Fibromyalgia: Normal Sensory Processing but Abnormal Evaluation
复制标题
DOI：
10.3390/brainsci10050306
复制
发表时间：
2020-05-01
期刊：
影响因子：
3.3
通讯作者：
Nagi, Saad S.
中科院分区：
文献类型：
--
作者：
Boehme, Rebecca;van Ettinger-Veenstra, Helene;Nagi, Saad S.
社交接触对人际交往很重要。轻柔的触摸和缓慢的刷牙通常被认为是令人愉快的，愉快的程度与c -触觉纤维（CT）的活动有关，这是皮肤上的一类无髓鞘神经。一般来说，无法体验快乐被称为快感缺乏，这是慢性疼痛纤维肌痛症的一种常见现象。在这里，我们研究的感知和皮层处理轻柔的触摸在一个特征良好的队列纤维肌痛。患者和对照组在接受前臂触觉刺激（刷）的同时参与功能性脑成像。他们被要求对触觉刺激的愉悦程度和持续的疼痛程度进行评分。我们发现纤维肌痛症患者有高度的痛苦、疼痛灾难、失眠和低感知健康状态。此外，患者认为慢速（ct -最优）和快速（ct -次优）刷牙都不如健康参与者愉快。虽然在触摸过程中大脑活动没有差异，但在愉悦等级和疼痛等级时，患者的右侧后岛（受刺激手臂的对侧）表现出失活。在健康的参与者中观察到相反的模式。基于体素的形态学分析显示，患者的双侧海马和前岛灰质密度降低。我们的研究结果表明，纤维肌痛症患者早期感觉加工完整，但评估加工功能不正常。这些发现有助于我们理解纤维肌痛症中快感缺乏的机制。
Social touch is important for interpersonal interaction. Gentle touch and slow brushing are typically perceived as pleasant, the degree of pleasantness is linked to the activity of the C-tactile (CT) fibers, a class of unmyelinated nerves in the skin. The inability to experience pleasure in general is called anhedonia, a common phenomenon in the chronic pain condition fibromyalgia. Here, we studied the perception and cortical processing of gentle touch in a well-characterized cohort of fibromyalgia. Patients and controls participated in functional brain imaging while receiving tactile stimuli (brushing) on the forearm. They were asked to provide ratings of pleasantness of the tactile stimulus and ongoing pain. We found high distress, pain catastrophizing, and insomnia, and a low perceived state of health in fibromyalgia. Further, patients rated both slow (CT-optimal) and fast (CT-suboptimal) brushing as less pleasant than healthy participants. While there was no difference in brain activity during touch, patients showed deactivation in the right posterior insula (contralateral to the stimulated arm) during pleasantness rating and activation during pain rating. The opposite pattern was observed in healthy participants. Voxel-based morphometry analysis revealed reduced grey matter density in patients, in the bilateral hippocampus and anterior insula. Our results suggest anhedonia to gentle touch in fibromyalgia with intact early-stage sensory processing but dysfunctional evaluative processing. These findings contribute to our understanding of the mechanisms underlying anhedonia in fibromyalgia.