基于注意力机制和深度学习的运动想象脑电信号分类方法

Classification of motor imagery EEG signals based on attention mechanism and deep learning

脑机接口(Brain Computer Interface,BCI)作为一种新型的信息沟通与控制手段,是一个涉及神经科学、信号处理以及模式识别等多个学科的交叉研究课题.基于运动想象的BCI系统被认为是最具发展前景的一种脑机接口系统.针对基于机器学习方法构建脑电特征与运动想象之间的映射关系进行分类时,现有方法仍存在无法兼顾脑电信号的时-空域特征并且分类精度难以提高的问题,提出一种基于注意力机制的双向长短时记忆网络(ABiLSTM)和卷积神经网络(Convolutional Neural Network,CNN)的运动想象脑电分析方法,通过ABiLSTM和CNN相结合的方式提取更具表征性的脑电信号深层特征,综合上述研究,最终构建的ABiLSTM-CNN分类模型在公共数据集上取得了90.72%的平均准确率,证明ABiLSTM-CNN运动想象脑电信号分类模型具有很理想的分类性能.

As a new means of information communication and control,brain computer interface(BCI)is an interdisciplinary research topic involving neuroscience,signal processing and pattern recognition.The BCI system based on motor imagination is regarded as one of the most promising BCI systems.The traditional electroencephalogram(EEG)classification methods based on machine learning complete the classification task by constructing the mapping relationship between EEG features and motor imagery.However,the existing methods still have problems that cannot take into account the time~spatial feature of EEG signals,and the classification accuracy is difficult to improve.In this paper,a motor imagery EEG classification method is constructed based on deep learning,and through the way of combining Bi-directional Long Short-Term Memory(LSTM)based on attention mechanism(ABiLSTM)with Convolutional Neural Network(CNN)to extract more in-depth characteristic of EEG signals.Based on the above research,the ABiLSTM-CNN has achieved an average accuracy of 90.72%on EEG Motor Imagery dataset.The results show that the ABiLSTM-CNN motor imagery EEG signal classification model has ideal classification performance.