Chaire de recherche Harland Sanders en Sciences de la vision, École d'Optométrie, Université de Montréal, Montréal, Québec, Canada BRAINlab, Department of Neuroscience and Pharmacology, Panum Institute, University of Copenhagen, Copenhagen, Denmark Laboratory of Clinical Biochemistry and Molecular Biology, University of Pisa Medical School, Pisa, Italy.
Pain. 2013 Oct;154(10):1973-1978. doi: 10.1016/j.pain.2013.05.036.
Vision is important for avoiding encounters with objects in the environment that may imperil physical integrity. We tested whether, in the absence of vision, a lower pain threshold would arise from an adaptive shift to other sensory channels. We therefore measured heat and cold pain thresholds and responses to suprathreshold heat stimuli in 2 groups of congenitally blind and matched normal-sighted participants. We also assessed detection thresholds for innocuous warmth and cold, and participants' attitude toward painful encounters in daily life. Our results show that, compared to sighted subjects, congenitally blind subjects have lower heat pain thresholds, rate suprathreshold heat pain stimuli as more painful, and have increased sensitivity for cold pain stimuli. Thresholds for nonpainful thermal stimulation did not differ between groups. The results of the pain questionnaires further indicated that blind subjects are more attentive to signals of external threats. These findings indicate that the absence of vision from birth induces a hypersensitivity to painful stimuli, lending new support to a model of sensory integration of vision and pain processing.
视觉对于避免遇到可能危及身体完整性的环境物体非常重要。我们测试了在没有视觉的情况下，是否会通过对其他感觉通道的适应性转移而产生较低的疼痛阈值。因此，我们测量了两组先天性盲人和匹配的正常视力参与者的热痛和冷痛阈值以及对超阈值热刺激的反应。我们还评估了无害温暖和寒冷的检测阈值，以及参与者对日常生活中疼痛遭遇的态度。我们的结果表明，与视力正常的受试者相比，先天性盲人的热痛阈值较低，对超阈值热痛刺激的评价更为痛苦，对冷痛刺激的敏感性也增加。非疼痛性热刺激的阈值在两组之间没有差异。疼痛问卷的结果进一步表明，盲人对外部威胁信号更加敏感。这些发现表明，从出生起就没有视力会导致对疼痛刺激的过度敏感，这为视觉和疼痛处理的感觉整合模型提供了新的支持。
