基于Morlet小波的事件相关脑磁图ERD/ERS分析方法

摘要

目的:验证基于Morlet小波的ERD/ERS计算方法在事件诱发脑磁图中的应用效果.方法:采用Morlet小波对事件相关脑磁图数据和静息状态下采集到的脑磁图数据进行小波变换,根据变换后的结果计算ERD/ERS值,分析alpha,beta,gamma频段的ERD/ERS值变化趋势.结果:通过对一段运动诱发脑磁图数据的分析,采用该方法得到的左、右运动皮层的ERD/ERS结果和文献中报道的结果相一致.结论:基于Morlet小波的事件相关脑磁图ERD/ERS分析方法能够有效分析事件诱发脑磁图的锁时但不锁相的变化.%Objective: To evaluate the validity of the ERD/ERS analysis based on Morlet wavelet transform, which is using to event-related MEG. Methods: The event-related MEG and the MEG in rest time are decomposed by Morlet wavelet transform. Then, the ERD/ERS can be calculated, and the ERD/ERS changes in alpha, beta, gamma band is analyzed. Results: The ERD/ERS calculated by wavelet transform is correct to the result from literature. Conclusion: These types of changes in MEG, which is time-locked but not phase-locked to the event, can be extracted by ERD/ERS analysis based on Morlet wavelet transform.