Department of Psychology, School of Health Sciences, Rey Juan Carlos University, Madrid, Spain; Clinical Foundation of the Rey Juan Carlos University, Madrid, Spain.
Department of Psychology, School of Health Sciences, Rey Juan Carlos University, Madrid, Spain.
Neuropsychologia. 2022 Feb 10;166:108141. doi: 10.1016/j.neuropsychologia.2021.108141. Epub 2022 Jan 4.
One of the major cognitive deficits in fibromyalgia has been linked to the hypervigilance phenomenon. It is mainly reflected as a negative bias for allocating attentional resources towards both threatening and pain-related information. Although the interest in its study has recently grown, the neural temporal dynamics of the attentional bias in fibromyalgia still remains an open question.
Fifty participants (25 fibromyalgia patients and 25 healthy control subjects) performed a dot-probe task. Two types of facial expressions (pain-related and neutral) were employed as signal stimuli. Then, as a target stimulus, a single dot replaced the location of one of these two faces. Event-related potentials (ERP) in response to facial expressions and target stimulation (i.e., dot) were recorded. Reaction time (RT) and accuracy measures in the experimental task were collected as behavioural outcomes.
Temporal dynamics of brain electrical activity were analysed on two ERP components (P2 and N2a) sensitive to the facial expressions meaning. Pain-related faces elicited higher frontal P2 amplitudes than neutral faces for the whole sample. Interestingly, an interaction effect between group and facial expressions was also found showing that pain-related faces elicited enhanced P2 amplitudes (at fronto-central regions, in this case) compared to neutral faces only when the group of patients was considered. Furthermore, higher P2 amplitudes were observed in response to pain-related faces in patients with fibromyalgia compared to healthy control participants. Additionally, a shorter latency of P2 (at centro-parietal regions) was also detected for pain-related facial expressions compared to neutral faces. Regarding the amplitude of N2a, it was lower for patients as compared to the control group. Non-relevant effects of the target stimulation on the ERPs were found. However, patients with fibromyalgia exhibited slower RT to locate the single dot for incongruent trials as compared to congruent and neutral trials.
Data suggest the presence of an attentional bias in fibromyalgia that it would be followed by a deficit in the allocation of attentional resources to further process pain-related information. Altogether the current results suggest that attentional biases in fibromyalgia might be explained by automatic attentional mechanisms, which seem to be accompanied by an alteration of more strategic or controlled attentional components.
纤维肌痛症的主要认知缺陷之一与过度警觉现象有关。它主要表现为对威胁和与疼痛相关的信息分配注意力资源的负面偏向。尽管最近对其研究的兴趣有所增加，但纤维肌痛症注意力偏向的神经时间动态仍然是一个悬而未决的问题。
50 名参与者（25 名纤维肌痛症患者和 25 名健康对照组）进行了点探测任务。两种面部表情（与疼痛相关和中性）被用作信号刺激。然后，作为目标刺激，一个单独的点取代了这两个面孔之一的位置。记录了对面部表情和目标刺激（即点）的事件相关电位（ERP）。实验任务中的反应时间（RT）和准确性测量作为行为结果收集。
对两个对面部表情含义敏感的 ERP 成分（P2 和 N2a）进行了脑电活动的时间动态分析。与中性面孔相比，疼痛相关面孔引起了整个样本中更高的额部 P2 振幅。有趣的是，还发现了组间和面部表情之间的交互作用效应，表明只有当考虑到患者组时，疼痛相关面孔才会引起比中性面孔更高的 P2 振幅（在额中央区域，在这种情况下）。此外，与健康对照组相比，纤维肌痛症患者对疼痛相关面孔的 P2 振幅更高。此外，与中性面孔相比，还检测到与疼痛相关的面部表情的 P2 潜伏期更短（在中央-顶区）。至于 N2a 的振幅，患者组的振幅低于对照组。在 ERPs 上还发现了与目标刺激无关的效应。然而，与一致和中性试验相比，纤维肌痛症患者在定位单个点时的 RT 更慢。
数据表明纤维肌痛症存在注意力偏向，这将导致对进一步处理与疼痛相关的信息分配注意力资源的缺陷。总的来说，当前的结果表明，纤维肌痛症中的注意力偏向可能可以通过自动注意机制来解释，这似乎伴随着更策略性或控制性注意成分的改变。
