一种基于心算任务的脑-机接口范式的研究  

A Study of Brain-Computer Interface Paradigm Based on Mental Arithmetic

作　　者：王陆洲[1] 王索刚[1] 匡光涛[1] 

机构地区：[1]天津医科大学生物医学工程学院,天津300070

出　　处：《生物医学工程学杂志》2013年第3期469-475,共7页Journal of Biomedical Engineering

基　　金：国家自然科学基金资助项目(61175118);高等学校博士学科点专项科研基金资助项目(20101202120006);天津市自然科学基金资助项目(12JCYBJC19500)

摘　　要：针对传统基于P300的脑-机接口(BCI)系统中,采集信号信噪比低,特征脑电(EEG)信号提供的信息量少的问题,提出一种视觉刺激下,利用大脑处理特定认知任务(心算任务)时能有效激活相关脑区和响应信号的特性,进而增强EEG特征的BCI范式,并与传统P300范式中计数任务进行对比。对实验所采集到的EEG数据进行去伪迹、分段、滤波等预处理,利用相干平均方法提取信号特征,分析了不同实验范式对事件相关电位(ERP)主要成分P300等特性的影响。改进的范式实验中,P300幅值平均提高了6.83μV,增幅达到73.94%;从400ms开始的脑区活动程度更为剧烈,时间更为持久;此外,不同于传统计数任务,心算任务在650ms处出现有明显的激活。表明改进的范式更能激活相关脑区、增强特征信号,可以为BCI提供一种新型系统范式。In the traditional P300 brain-computer interface （BCI） system, the electroencephalogram （EEG） signals can only provide limited information with a low signal-to-noise ratio. A BCI paradigm under visual stimulus was pro- posed in our study aiming to effectively activate the related brain areas and response signal while dealing with specific cognitive task （mental arithmetic task）, so as to enhance the EEG signals. The result was compared with the traditional P300 counting task paradigm. Then the collected EEG data were preprocessed including extracting signal features with coherent averaging method, and analyzing the influences of different experimental paradigms on main components of event related potential （ERP）. In the improved paradigm experiments the average increasing rate of P300 amplitude was 6.83μV （73.94%）. The brain activity from 400ms was more active and lasted longer. Besides, unlike traditional counting task, mental arithmetic task appeared to have apparent activation at 650ms. The results showed that the improved paradigm could activate the related brain areas better and enhance the characteristics of signal. This provides a new system paradigm for BCI.

关 键 词：事件相关电位 脑一机接口 范式 心算任务 

分 类 号：R318.04[医药卫生—生物医学工程]