基于头皮拉普拉斯脑电电极的高空间分辨率SSVEP信号采集与分析研究  

Research on High Spatial Resolution SSVEP Signal Acquisition and Analysis Based on Scalp Laplace EEG Electrodes

作　　者：许敏鹏 丁茹梦[1] 郑春厚 蔡雨 李辉 明东[1,2] XU Minpeng;DING Rumeng;ZHENG Chunhou;CAI Yu;LI Hui;MING Dong(Academy of Medical Engineering and Translational Medicine,Tianjin University,Tianjin 300072,China;School of Precision Instrument and Opto-electronics Engineering,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学医学工程与转化医学研究院,天津300072 [2]天津大学精密仪器与光电子工程学院,天津300072

出　　处：《信号处理》2023年第8期1455-1464,共10页Journal of Signal Processing

基　　金：国家自然科学基金项目(62122059,61976152,81925020)。

摘　　要：脑电信号(Electroencephalogram,EEG)因其具有时间分辨率高、方便易得等优点被广泛应用。然而脑电信号的空间分辨率较低,导致其应用效果受限。拉普拉斯滤波方法已被证明可提高体表电位的空间分辨率。传统拉普拉斯脑电研究通常利用算子来估计圆盘电极阵列中的拉普拉斯电势。但是圆盘电极间距大,使得该方法估计结果精度较低。针对上述问题,本文设计了一种拉普拉斯脑电电极及其采集方案,分别从仿真实验和人体实验两方面验证了其有效性。仿真结果表明拉普拉斯电极空间分辨率可比传统圆盘电极提高约41.4%。人体实验结果表明大脑左右半球视觉皮层同时产生稳态视觉诱发电位(Steady-state visual evoked potentials,SSVEP)时,拉普拉斯脑电信号可明显分辨出左右半球两个独立的SSVEP源信号,而传统脑电信号无法区分这两个独立脑电源。上述研究结果证明,本文设计的拉普拉斯脑电电极及其采集方案能够有效提升脑电的空间分辨率,有望实现更精确的脑电源定位。EEG signals are widely used due to their advantages of high temporal resolution and convenience.However,the low spatial resolution of EEG signals limits the effectiveness of EEG application.Laplacian filtering methods have been proved to improve the spatial resolution of body surface potentials.The traditional Laplace EEG research usually utilize algorithms to estimate Laplace potentials through the disc electrode arrays.However,the distance between the disc electrodes usually are far away,which makes the estimation results of this method less accurate.This study proposed to use Laplace EEG electrode to improve the spatial resolution of EEG signals,which was verified by both simulation experiments and real human EEG experiments.The simulation results show that the spatial resolution of the Laplace electrode is about 41.4%higher than that of the traditional disc electrode.The results of EEG experiments show when the visual cortices of left and right hemispheres simultaneously produced steady-state visual evoked potentials(SSVEPs),the left and right SSVEP sources could be clearly distinguished from Laplace EEG signals but not from the traditional EEG signals.These results indicate that the Laplace EEG electrode proposed in this study can effectively improve the spatial resolution of EEG,and the Laplace EEG is expected to achieve more accurate EEG source location.

关 键 词：头皮拉普拉斯脑电 稳态视觉诱发电位 拉普拉斯脑电电极 

分 类 号：R318[医药卫生—生物医学工程]