Motor imagery EEG signal classification using deep learning for brain computer interfaces

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2017
Rezaaei Tabar, Yousef
In this thesis we proposed a novel method for classification of Motor Imagery (MI) EEG signals based on deep learning. Convolutional Neural Networks (CNN) and Stacked Autoencoders (SAE) networks were investigated for MI EEG classification. A new form of input is introduced to combine time, frequency and location information extracted from EEG signal and also a new deep network combining CNN and SAE is proposed in this thesis. In the proposed network, the features that are extracted by CNN are classified through the deep SAE network. The results obtained on public datasets revealed that the proposed method provides better classification performance compared to other state of art approaches. Furthermore, four different experiments were conducted on totally 16 subjects to collect MI EEG signals in addition to public datasets. Two of these experiments were used to record motor imagery data and perform offline classification. Online feedback was provided in the other two sets of experiments, where EEG signal was classified in real time and appropriate visual feedback was presented to the subject during the experiment. Our proposed signal processing method was applied to the recorded data as well as public datasets and compared with present state of art methods.

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Citation Formats
Y. Rezaaei Tabar, “Motor imagery EEG signal classification using deep learning for brain computer interfaces,” Ph.D. - Doctoral Program, Middle East Technical University, 2017.