EEG-based classification combining Bayesian convolutional neural networks with recurrence plot for motor movement/imagery

Electroencephalogram (EEG)-based Motor imagery (MI) is a key topic in the brain-computer interface (BCI). The EEG-based real execution and motor imagery multi-class classification tasks are also crucial, but only a few kinds of literature research it. In addition, classification accuracy still has room for improvement, and the inter-individual variability problems in BCI applications need to be solved. To address these issues, we developed a novel model (RP-BCNNs) that combines the recurrence plot (RP) and Bayesian Convolutional Neural Networks (BCNNs). First, we employ an RP computation for preprocessed EEG signals of each channel and merge all RPs of all channels into one based on the weighted average method. Then, we feed the RP features into BCNNs to classify 2-class, 3-class, 4-class, and 5-class on real/imaginary movements classification tasks. The results show that the RP-BCNNs model outperforms the state-of-the-art methods, achieving average accuracies of 92.86%, 94.12%, 91.37%, 92.61% for real movements and 94.07%, 93.77%, 90.54%, 91.85% for imaginary movements. Our findings suggest that combining complex network methods with deep learning can improve the classification performance of EEG-based BCI systems (e.g., motor imagery, emotion recognition, and epileptic seizure classification).