Hong Keum-Shik, Bhutta M Raheel, Liu Xiaolong, Shin Yong-Il
School of Mechanical Engineering, Pusan National University, Busan 46241, South Korea; Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 46241, South Korea.
Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 46241, South Korea.
Behav Brain Res. 2017 Aug 30;333:225-234. doi: 10.1016/j.bbr.2017.06.034. Epub 2017 Jun 28.
The ability of the somatosensory cortex in differentiating various tactile sensations is very important for a person to perceive the surrounding environment. In this study, we utilize a lab-made multi-channel functional near-infrared spectroscopy (fNIRS) to discriminate the hemodynamic responses (HRs) of four different tactile stimulations (handshake, ball grasp, poking, and cold temperature) applied to the right hand of eight healthy male subjects. The activated brain areas per stimulation are identified with the t-values between the measured data and the desired hemodynamic response function. Linear discriminant analysis is utilized to classify the acquired data into four classes based on three features (mean, peak value, and skewness) of the associated oxy-hemoglobin (HbO) signals. The HRs evoked by the handshake and poking stimulations showed higher peak values in HbO than the ball grasp and cold temperature stimulations. For comparison purposes, additional two-class classifications of poking vs. temperature and handshake vs. ball grasp were performed. The attained classification accuracies were higher than the corresponding chance levels. Our results indicate that fNIRS can be used as an objective measure discriminating different tactile stimulations from the somatosensory cortex of human brain.
体感皮层区分各种触觉的能力对于一个人感知周围环境非常重要。在本研究中，我们使用实验室自制的多通道功能近红外光谱（fNIRS）来区分应用于八名健康男性受试者右手的四种不同触觉刺激（握手、抓球、戳刺和冷温度）的血流动力学反应（HRs）。每次刺激激活的脑区通过测量数据与期望的血流动力学反应函数之间的t值来确定。线性判别分析用于根据相关氧合血红蛋白（HbO）信号的三个特征（均值、峰值和偏度）将采集的数据分为四类。握手和戳刺刺激诱发的HRs在HbO中的峰值高于抓球和冷温度刺激。为了进行比较，还进行了戳刺与温度以及握手与抓球的两类分类。获得的分类准确率高于相应的随机水平。我们的结果表明，fNIRS可作为一种客观测量方法，用于区分来自人类大脑体感皮层的不同触觉刺激。
