不同视觉刺激模式对视觉诱发电位的影响

Effects of different visual stimulation patterns on visual evoked potentials

目的:通过视觉诱发电位探索适合的脑机接口视觉刺激模式。方法:采用Active One生理信号测量系统和双计算机构建实验系统。利用VC++语言编程,设计多种视觉刺激模式:模块闪烁方式、模块背景图案变化方式、模块字符变化方式。采用累加平均和小波滤波方法提取视觉诱发电位。结果:可以检测到多种视觉刺激模式引发的视觉诱发电位信号,不同刺激模式引发的诱发电位波形及诱出率存在差别。结论:模块闪烁、刺激模块棋盘格翻转、条纹变化、字符跳动等视觉刺激模式能引发波形幅度较大,易识别的视觉诱发电位信号,适用于脑机接口。在脑机接口应用中应提供多种视觉刺激模式供使用者选择。

Objective： To explore the suitable visual stimulation patterns for brain-computer interface.Method：The experimental system was established with the Active One physiological signal measurement system and two computers. Different visual stimulation patterns were designed through visual C＋＋ programming： block flickering;change of the block background image; change of the character on the block. Visual evoked potentials were derived using averaging method and wavelet filtering,Result：Visual evoked potentials corresponding to several different stimulation patterns were detected, There are differences in the waveform and VEP detection rate clue to different stimulation pattern.Condusion：Block flickering, checkerboard flipping, stripes alternating and character moving are suitable visual stimulation patterns for brain-computer interface which can induce bigger and recognizable visual evoked potentials. There should be multiple patterns for user to choose in brain-computer interface application,