Nardelli Mimma, Valenza Gaetano, Bianchi Matteo, Greco Alberto, Lanata Antonio, Bicchi Antonio, Scilingo Enzo Pasquale
Annu Int Conf IEEE Eng Med Biol Soc. 2015;2015:298-301. doi: 10.1109/EMBC.2015.7318359.
This study reports on the development of a gender-specific classification system able to discern between two levels of velocity of a caress-like stimulus, through information gathered from Autonomic Nervous System (ANS) linear and nonlinear dynamics. Specifically, caress-like stimuli were administered to 32 healthy volunteers (16 males) while monitoring electrocardiogram signal to extract Heart Rate Variability (HRV) series. Caressing stimuli were administered to the forearm at a fixed force level (6 N) and two levels of velocity, 9.4 mm/s and 37 mm/s. Standard HRV measures, defined in the time and frequency domain, as well as HRV nonlinear measures were extracted during the pre- and post-stimulus sessions, and given as an input to a Support Vector Machine (SVM) classifier implementing a leave-one-subject-out procedure. Results show an accuracy of velocity recognition of 70% for the men, and 84.38% for the women, when both standard and nonlinear HRV measures were taken into account. Conversely, non-significant results were achieved considering standard measures only, or a gender-aspecific classification. We can conclude that caress-like stimuli elicitation significantly affect HRV nonlinear dynamics with a highly specific gender dependency.
本研究报告了一种特定性别的分类系统的开发，该系统能够通过从自主神经系统（ANS）线性和非线性动力学收集的信息，区分两种类似爱抚刺激的速度水平。具体而言，在监测心电图信号以提取心率变异性（HRV）系列时，对32名健康志愿者（16名男性）施加了类似爱抚的刺激。以固定的力水平（6 N）和两种速度水平，即9.4 mm/s和37 mm/s，对前臂进行爱抚刺激。在刺激前和刺激后的时段提取了在时域和频域中定义的标准HRV测量值以及HRV非线性测量值，并将其作为输入提供给实施留一法程序的支持向量机（SVM）分类器。结果表明，当同时考虑标准和非线性HRV测量值时，男性的速度识别准确率为70%，女性为84.38%。相反，仅考虑标准测量值或进行非特定性别的分类时，结果不显著。我们可以得出结论，类似爱抚刺激的诱发会显著影响HRV非线性动力学，且具有高度特定的性别依赖性。
