Journal of Neuroscience Methods ( IF 3 ) Pub Date : 2020-08-05 , DOI: 10.1016/j.jneumeth.2020.108892 Zhanna Garakh 1 , Vladimir Novototsky-Vlasov 2 , Ekaterina Larionova 1 , Yuliya Zaytseva 3
Background
EEG mu rhythm suppression is assessed in experiments on the execution, observation and imagination of movements. It is utilised for studying of actions, language, empathy in healthy individuals and preservation of sensorimotor system functions in patients with schizophrenia and autism spectrum disorders. While EEG alpha and mu rhythms are recorded in the same frequency range (8−13 Hz), their specification becomes a serious issue.
The new method
is based on the spatial and functional characteristics of the mu wave, which are: (1) the mu rhythm is located over the sensorimotor cortex; (2) it desynchronises during movement processing and does not respond on the eyes opening. In EEG recordings, we analysed the mu rhythm under conditions with eyes opened and eyes closed (baseline), and during a motor imagery task with eyes closed. EEG recordings were processed by principal component analysis (PCA).
Results
The analysis of EEG data with the proposed approach revealed the maximum spectral power of mu rhythm localised in the sensorimotor areas. During motor imagery, mu rhythm was suppressed more in frontal and central sites than in occipital sites, whereas alpha rhythm was suppressed more in parietal and occipital sites. Mu rhythm desynchronization in sensorimotor sites during motor imagery was greater than alpha rhythm desynchronization.
The proposed method enabled EEG mu rhythm separation from its mix with alpha rhythm.
Conclusions
EEG mu rhythm separation with the proposed method satisfies its classical definition.
中文翻译:
从具有α节奏的混合音中分离出Mu节奏:主成分分析和因子地形。
背景
在执行,观察和想象动作的实验中评估了脑电图节律抑制。它用于研究精神分裂症和自闭症谱系障碍患者的行为,语言,健康个体的同情心以及保留感觉运动系统功能。尽管脑电图的alpha和mu节律是在相同的频率范围(8-13 Hz)中记录的,但它们的规范却成为一个严重的问题。
新方法
基于mu波的空间和功能特性,它们是:(1)mu节奏位于感觉运动皮层上方;(2)在运动过程中不同步,并且睁眼不响应。在EEG记录中,我们分析了在睁眼和闭眼(基线)的条件下以及在闭眼的运动成像任务期间的mu节律。脑电图记录通过主成分分析(PCA)处理。
结果
用提出的方法对EEG数据的分析揭示了位于感觉运动区域的μ节律的最大频谱功率。在运动成像过程中,额叶和中央部位的mu节律比枕骨部位受到的抑制更大,而顶叶和枕骨部位的α节律受到的抑制更大。运动成像期间感觉运动部位的Mu节律失步大于alpha节律失步。
所提出的方法能够使脑电图从其与阿尔法节奏的混合中分离出来。
结论
所提出的方法进行脑电心律分离符合其经典定义。