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Emotion recognition is one of the most important research directions in the field of brain–computer interface (BCI). However, to conduct electroencephalogram (EEG)-based emotion recognition, there exist difficulties regarding EEG signal processing; moreover, the performance of classification models in this regard is restricted. To counter these issues, the 2022 World Robot Contest successfully held an affective BCI competition, thus promoting the innovation of EEG-based emotion recognition. In this paper, we propose the Transformer-based ensemble (TBEM) deep learning model. TBEM comprises two models: a pure convolutional neural network (CNN) model and a cascaded CNN-Transformer hybrid model. The proposed model won the abovementioned affective BCI competition’s final championship in the 2022 World Robot Contest, demonstrating the effectiveness of the proposed TBEM deep learning model for EEG-based emotion recognition.


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Transformer-based ensemble deep learning model for EEG-based emotion recognition

Show Author's information Xiaopeng Si1,2,§( )Dong Huang1,2,§Yulin Sun1,2,§Shudi Huang1,2He Huang1,2Dong Ming1,2( )
Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China
Tianjin Key Laboratory of Brain Science and Neural Engineering, Tianjin University, Tianjin 300072, China

§ These authors contributed equally to this work.

Abstract

Emotion recognition is one of the most important research directions in the field of brain–computer interface (BCI). However, to conduct electroencephalogram (EEG)-based emotion recognition, there exist difficulties regarding EEG signal processing; moreover, the performance of classification models in this regard is restricted. To counter these issues, the 2022 World Robot Contest successfully held an affective BCI competition, thus promoting the innovation of EEG-based emotion recognition. In this paper, we propose the Transformer-based ensemble (TBEM) deep learning model. TBEM comprises two models: a pure convolutional neural network (CNN) model and a cascaded CNN-Transformer hybrid model. The proposed model won the abovementioned affective BCI competition’s final championship in the 2022 World Robot Contest, demonstrating the effectiveness of the proposed TBEM deep learning model for EEG-based emotion recognition.

Keywords: deep learning, ensemble learning, Transformer, electroencephalogram, affective brain–computer interface

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Publication history

Received: 29 March 2023
Revised: 08 May 2023
Accepted: 24 May 2023
Published: 05 September 2023
Issue date: September 2023

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© The authors 2023.

Acknowledgements

All authors thank Haolin Wu (Tsinghua University), Dan Zhang (Tsinghua University), and Chengcheng Hong (Beijing University of Posts and Telecommunications) for their support in providing the data for the final competition.

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