摘要
首次研究双眼双频刺激下α波相位同步程度,以解决目前双眼同频刺激模式存在的频率选择局限问题。对采集的脑电信号数据用50 Hz陷波,经带宽为f_I-3 Hz～f_I+3 Hz(f_I为自发α波频率)的带通滤波器去噪得α波数据,对所有通道数据去趋势和眼电。用希尔伯特变换计算α波和刺激信号瞬时相位,用二者相位差的归一化香农熵衡量α波同步程度。结果表明:双眼双频刺激下,第一只眼的刺激频率为低、中或高频,第二只眼在f_I±2. 4 Hz、2f_I±2. 4 Hz、4f_I±2. 4 Hz取值,则α波与后者刺激信号的同步程度均呈阿诺德舌头;三个频段的α波同步程度依次减少。此外,可通过调整其中一只眼睛的刺激频率,来改变另一只眼的α波同步程度。双眼双频刺激范式给研究大脑α波同步程度提供更多的频率选择,为更好研究知觉和认知功能关系及认知障碍诊断与治疗提供新思路。
To solve the problem of frequency selection limitation in the binocular single-frequency stimulation mode,this article study the changes of phase entrainment of brain α wave in the occipital region under binocular dual-frequency simultaneous periodic stimulation for the first time. The 50Hz notch is used for the collected EEG data, the α wave data is de-noised by the band pass filter with bandwidth fI -3 Hz~ fI +3 Hz ( f I is spontaneous α wave frequency), and the trend and eye electricity are removed for all the channel data. The instantaneous phase of α wave and stimulus signal is calculated by Hilbert transform, and the degree of α wave entrainment is measured by the normalized Shannon entropy of the phase difference between the phase of α wave and stimulus signal. The results showed that under the stimulation of binocular dual-frequency, if one of the eyes is stimulated at low, medium or high frequency, and another eye is stimulated at frequency at fI ±2.4Hz、2fI±2.4Hz、4fI ±2.4Hz, the degree of phase entrainment between α wave and the frequency stimulated later eye was consistent with the change rule of the Arnold ’ s tongue. The degree of α wave entrainment was weakened in turn in the three bands. Moreover, the degree of α wave entrainment of one eye can be changed by selecting the frequency to stimulate the other eye. The binocular dual-frequency simultaneous stimulation paradigm can provide more stimulation frequencies selection for studying the degree of brain α wave entrainment, which should be a new idea for researching more effectively on the relationship between perception and cognitive function and its potential diagnosis and treatment of cognitive impairment.
作者
覃玉荣
时文健
黄钰清
赵进创
QIN Yu-rong;SHI Wen-jian;HUANG Yu-qing;ZHAO Jin-chuang(School of Computer and Electronics Information, Guangxi University, Nanning, Guangxi 530004, China)
出处
《信号处理》
CSCD
北大核心
2019年第1期132-140,共9页
Journal of Signal Processing
基金
国家自然科学基金(81560523)
广西自然科学基金(2016GXNSFAA380068)
关键词
双眼双频同时刺激
大脑α波
相位同步程度
binocular dual-frequency stimulation
brain α wave
degree of phase entrainment
