Pidal-Miranda Marina, González-Villar A J, Carrillo-de-la-Peña M T
Department of Clinical Psychology and Psychobiology, University of Santiago de Compostela, Santiago de Compostela, Spain.
Psychological Neuroscience Lab, Research Center in Psychology, School of Psychology, University of Minho, Braga, Portugal.
Front Behav Neurosci. 2019 Jan 8;12:323. doi: 10.3389/fnbeh.2018.00323. eCollection 2018.
Fibromyalgia (FM) is a generalized chronic pain condition associated with a variety of symptoms, including altered cognitive and emotional processing. It has been proposed that FM patients show a preferential allocation of attention to information related to the symptoms of the disease, particularly to pain cues. However, the existing literature does not provide conclusive evidence on the presence of this attentional bias, and its effect on cognitive functions such as inhibitory control. To clarify this issue, we recorded the electroencephalographic activity of 31 women diagnosed with FM and 28 healthy women, while performing an emotional Go/NoGo task with micro-videos of pain, happy, and neutral facial expressions. We analyzed behavioral data, performed EEG time-frequency analyses, and obtained the event-related potentials (ERPs) N2 and P3 components in NoGo trials. A series of self-reports was also administered to evaluate catastrophic thinking and the main symptoms of fibromyalgia. Pain expressions were associated with longer reaction times and more errors, as well as with higher theta and delta power, and P3 amplitude to NoGo stimuli. Thus, behavioral and psychophysiological data suggest that increased attention to pain expressions impairs the performance of an inhibitory task, although this effect was similar in FM patients and healthy controls. N2 amplitude was modulated by type of facial expression (larger to pain faces), but only for the control group. This finding suggests that the presentation of pain faces might represent a smaller conflict for the patients, more used to encounter pain stimuli. No main group effects were found significant for N2 or P3 amplitudes, nor for time-frequency data. Using stimuli with greater ecological validity than in previous studies, we could not confirm a greater effect of attentional bias toward negative stimuli over inhibitory performance in patients with FM. Studying these effects allow us to better understand the mechanisms that maintain pain and develop intervention strategies to modify them.
纤维肌痛（FM）是一种全身性慢性疼痛病症，伴有多种症状，包括认知和情绪加工改变。有人提出，纤维肌痛患者会优先将注意力分配到与疾病症状相关的信息上，尤其是疼痛线索。然而，现有文献并未提供关于这种注意力偏差存在的确凿证据，以及其对诸如抑制控制等认知功能的影响。为了阐明这个问题，我们记录了31名被诊断为纤维肌痛的女性和28名健康女性在观看疼痛、快乐和中性面部表情的微视频并执行情绪Go/NoGo任务时的脑电图活动。我们分析了行为数据，进行了脑电图时频分析，并在NoGo试验中获得了事件相关电位（ERP）的N2和P3成分。还进行了一系列自我报告以评估灾难化思维和纤维肌痛的主要症状。疼痛表情与更长的反应时间、更多的错误相关，也与更高的θ波和δ波功率以及对NoGo刺激的P3波幅相关。因此，行为和心理生理数据表明，对疼痛表情关注度的增加会损害抑制任务的表现，尽管这种效应在纤维肌痛患者和健康对照组中相似。N2波幅受面部表情类型的调节（对疼痛面孔更大），但仅在对照组中如此。这一发现表明，疼痛面孔的呈现对患者来说可能代表较小的冲突，因为他们更习惯于遇到疼痛刺激。在N2或P3波幅以及时频数据方面未发现显著的主要组效应。使用比以往研究具有更高生态效度的刺激，我们无法证实纤维肌痛患者对负面刺激的注意力偏差对抑制表现有更大影响。研究这些效应有助于我们更好地理解维持疼痛的机制，并制定干预策略来改变它们。
