Institute of Brain and Psychological Sciences, Sichuan Normal University, Chengdu, China.
Center for Machine Vision and Signal Analysis (CMVS), University of Oulu, Oulu, Finland.
Eur J Pain. 2023 Jul;27(6):668-681. doi: 10.1002/ejp.2097. Epub 2023 Mar 10.
Pain can have a significant impact on an individual's life, as it has both cognitive and affective consequences. However, our understanding of how pain affects social cognition is limited. Previous studies have shown that pain, as an alarm stimulus, can disrupt cognitive processing when focal attention is required, but whether pain also affects task-irrelevant perceptual processing remains unclear.
We examined the effect of laboratory-induced pain on event-related potentials (ERPs) to neutral, sad and happy faces before, during and after a cold pressor pain. ERPs reflecting different stages of visual processing (P1, N170 and P2) were analysed.
Pain decreased the P1 amplitude for happy faces and increased the N170 amplitude for happy and sad faces compared to the pre-pain phase. The effect of pain on N170 was also observed in the post-pain phase. The P2 component was not affected by pain.
Our results suggest that pain alters both featural (P1) and structural face-sensitive (N170) visual encoding of emotional faces, even when the faces are irrelevant to the task. While the effect of pain on initial feature encoding seemed to be disruptive and specific to happy faces, later processing stages showed long-lasting and increased activity for both sad and happy emotional faces.
The observed alterations in face perception due to pain may have consequences for real-life interactions, as fast and automatic encoding of facial emotions is important for social interactions.
疼痛会对个体生活产生重大影响，因为它既有认知后果，也有情感后果。然而，我们对疼痛如何影响社会认知的理解是有限的。先前的研究表明，疼痛作为一种警报刺激，在需要集中注意力时会干扰认知加工，但疼痛是否也会影响与任务无关的感知加工尚不清楚。
我们在冷加压疼痛前、中、后，检查了实验室诱导的疼痛对中性、悲伤和快乐面孔的事件相关电位（ERPs）的影响。分析了反映不同视觉加工阶段（P1、N170 和 P2）的 ERP。
与疼痛前阶段相比，疼痛降低了快乐面孔的 P1 振幅，并增加了快乐和悲伤面孔的 N170 振幅。疼痛对 N170 的影响也出现在疼痛后阶段。疼痛对 P2 成分没有影响。
我们的结果表明，疼痛改变了情绪面孔的特征（P1）和结构敏感（N170）的视觉编码，即使这些面孔与任务无关。虽然疼痛对初始特征编码的影响似乎具有破坏性且仅针对快乐面孔，但后期处理阶段对悲伤和快乐情绪面孔的活动表现出持久和增强。
由于疼痛而导致的面孔感知的改变可能对现实生活中的互动产生影响，因为对面部情绪的快速和自动编码对于社交互动很重要。
