Mørch Carsten Dahl, Andersen Ole Kaeseler, Graven-Nielsen Thomas, Arendt-Nielsen Lars
Center for Sensory-Motor Interaction (SMI), Aalborg University, Fredrik Bajers Vej 7 D-3, DK-9220 Aalborg, Denmark.
J Neurosci Methods. 2007 Feb 15;160(1):85-92. doi: 10.1016/j.jneumeth.2006.08.014. Epub 2006 Sep 22.
Nociceptive withdrawal reflexes (NWR) were evoked by brief (200 ms) painful CO(2) laser stimulation at five intensities (1.2, 1.4, 1.6, 1.8, and 2.0 x pain threshold) applied to nine sites (2 cm(2)) separated by 1.7 cm on the dorsal side of the foot and anterior part of the lower leg of 14 healthy volunteers. The purpose of the study was to investigate the characteristics of NWRs evoked by a natural stimulation modality. The reflexes were measured as the electromyographic response from the iliopsoas (ILI), quadriceps vastus lateralis (QVL), biceps femoris (BF), tibialis anterior (TA), and soleus (SOL) muscles. Stimulus-response relationships between heat intensity and the reflex magnitude and correlation between perceived pain intensity and reflex magnitude were observed in the ILI, QVL, BF, and TA but not the SOL. No significant differences in reflex magnitude were found between the stimulation sites. NWRs were evoked more often in flexor muscles than extensor muscles, indicating a non-site-specific reflex organization. The paper presents a new method to evoke NWRs by uniform-temperature laser heat stimulation of large skin areas in humans. These heat evoked reflexes had a stimulus-response relationship.
对14名健康志愿者的足部背侧和小腿前部，用短暂（200毫秒）的疼痛性二氧化碳激光以五种强度（1.2、1.4、1.6、1.8和2.0倍疼痛阈值）刺激九个间隔1.7厘米的部位（2平方厘米），诱发伤害性退缩反射（NWR）。本研究的目的是调查由自然刺激方式诱发的NWR的特征。反射通过测量髂腰肌（ILI）、股外侧肌（QVL）、股二头肌（BF）、胫骨前肌（TA）和比目鱼肌（SOL）的肌电图反应来记录。在ILI、QVL、BF和TA中观察到热强度与反射幅度之间的刺激 - 反应关系以及感知疼痛强度与反射幅度之间的相关性，但在SOL中未观察到。刺激部位之间的反射幅度没有显著差异。NWR在屈肌中比伸肌中更常被诱发，表明存在非部位特异性的反射组织。本文提出了一种通过对人体大面积皮肤进行均匀温度激光热刺激来诱发NWR的新方法。这些热诱发反射具有刺激 - 反应关系。
