García González María, Ardizone-García Ignacio, Soto-Goñi Xabier, Jiménez-Órtega Laura
Department of Clinical Dentistry, Faculty of Biomedical Sciences, European University of Madrid, Madrid, Spain; Neuroscience of Emotion, Cognition, and Nociception group (NeuroCEN), Psychobiology & Behavioral Sciences Methods Department, Faculty of Odontology, University Complutense of Madrid, Plaza de Ramón y Cajal, SN., Madrid, Spain; Psychology and Orofacial Pain Working Group, Sociedad Española de Disfunción Craneomandibular y Dolor Orofacial (SEDCYDO), Madrid, Spain.
Conservative Dentistry and Prosthetics, Faculty of Odontology, University of Madrid, Campus de Monchoal, Plaza de Ramon y Cajal, S.N., Madrid, España.
J Manipulative Physiol Ther. 2024 Jul-Dec;47(5-9):155-165. doi: 10.1016/j.jmpt.2024.09.009. Epub 2024 Oct 30.
The purpose of this study was to analyze the influence of pain and no pain expectation on pupil diameter and the cognitive assessment of pain using pupillometry and the visual analog scale (VAS).
This was an experimental cross-sectional study in which painful stimulation of the muscle masseter was produced by palpation with an algometer in a sample of 30 healthy participants. Before the painful stimulation, pain expectation and no pain expectation situations were induced by employing instructional videos. Cognitive and physiological pain responses were measured by the VAS and by pupillometry. Visual analog scale score was assessed at the end of each experimental condition, and pupillometry measurements were recorded at different moments of the experimental process (events).
The pain score and larger pupil diameter for all events (except, as expected, for the initial baseline), were statistically significant for the pain expectation condition compared with the no pain expectation.
Within the conditions of this study, pain expectation modulated both cognitive assessment of pain (VAS) and pupil diameter. These findings suggest that pupil diameter may be a useful and complementary tool with the VAS for pain assessment. Furthermore, the findings support models postulating that emotion and cognition are important aspects involved in pain perception, which is in line with the recent International Association for the Study of Pain definition of pain.
本研究旨在通过瞳孔测量法和视觉模拟量表（VAS）分析疼痛预期和无疼痛预期对瞳孔直径及疼痛认知评估的影响。
这是一项实验性横断面研究，对30名健康参与者样本通过用痛觉计触诊产生咬肌疼痛刺激。在疼痛刺激前，通过播放指导视频诱导产生疼痛预期和无疼痛预期情况。通过VAS和瞳孔测量法测量认知和生理疼痛反应。在每个实验条件结束时评估视觉模拟量表评分，并在实验过程的不同时刻（事件）记录瞳孔测量结果。
与无疼痛预期相比，疼痛预期条件下所有事件（预期初始基线除外）的疼痛评分和更大的瞳孔直径具有统计学意义。
在本研究条件下，疼痛预期调节了疼痛的认知评估（VAS）和瞳孔直径。这些发现表明，瞳孔直径可能是一种与VAS结合使用的有用且互补的疼痛评估工具。此外，这些发现支持了假设情绪和认知是疼痛感知重要方面的模型这与国际疼痛研究协会最近对疼痛的定义一致。
