Integrative Neuroscience group within Center for Sensory-Motor Interaction, Department of Health Science and Technology, Aalborg University, Fredrik Bajersvej 7D3, 9220 Aalborg, Denmark.
Med Biol Eng Comput. 2013 Sep;51(9):999-1009. doi: 10.1007/s11517-013-1079-9. Epub 2013 Apr 27.
During electrocutaneous stimulations, variation in skin properties across locations can lead to differences in neural activation. However, little focus has been given to the effect of different skin thicknesses on neural activation. Electrical stimulation was applied to six sites across the sole of the foot. The intensities used were two and four times perception threshold. The subjects (n = 8) rated the perception quality and intensity using the McGill Pain Questionnaire and a visual analog scale (VAS). A finite element model was developed and combined with the activation function (AF) to estimate neural activation. Electrical stimulation was perceived as significantly less sharp at the heel compared to all other sites, except one site in the forefoot (logistic regression, p < 0.05). The VAS scores were significantly higher in the arch than at the heel (RM ANOVA, p < 0.05). The model showed that the AF was between 91 and 231 % higher at the five other sites than at the heel. The differences in perception across the sole of the foot indicated that the CNS received different inputs depending on the stimulus site. The lower AF at the heel indicated that the skin thicknesses could contribute to the perceived differences.
在电刺激过程中，皮肤特性在不同位置的变化可能导致神经激活的差异。然而，很少有人关注不同皮肤厚度对神经激活的影响。电刺激应用于足底的六个部位。使用的强度为感知阈值的两倍和四倍。受试者（n=8）使用 McGill 疼痛问卷和视觉模拟量表（VAS）来评定感知质量和强度。开发了一个有限元模型，并与激活函数（AF）结合，以估计神经激活。与其他所有部位相比，脚跟处的电刺激感觉明显不那么尖锐，除了前脚的一个部位（逻辑回归，p<0.05）。与脚跟相比，足弓处的 VAS 评分明显更高（RM ANOVA，p<0.05）。该模型表明，在其他五个部位的 AF 比在脚跟处高 91%至 231%。足底的感知差异表明，中枢神经系统根据刺激部位接收不同的输入。脚跟处的 AF 较低表明，皮肤厚度可能导致感知差异。
