Document Type : Original/Review Paper

Authors

1 Master's student

2 Assistant Professor Faculty of Electrical Engineering

Abstract

Human emotion recognition based on electroencephalogram signals remains a significant challenge in computational neuroscience and artificial intelligence. Convolutional neural networks have been widely adopted to address this challenge due to their strong capabilities in feature extraction and representation learning. Empirical tuning of hyperparameters, however, is often inefficient and prone to suboptimal solutions. To overcome this limitation, the Grey Wolf Optimizer and Whale Optimization Algorithm—two swarm intelligence–based metaheuristic methods—were employed to refine the architecture and learning hyperparameters of a baseline convolutional neural network. Performance was evaluated on the SEED EEG dataset for emotion recognition. Experimental results showed that the optimized model achieved an accuracy of 86% compared to 83% for the baseline, with the confusion matrix confirming reduced misclassification errors and improved recognition of emotional states. Beyond accuracy, the optimization process also lowered the number of trainable parameters and computational overhead, thereby enhancing efficiency. These findings highlight that swarm intelligence–based methods provide superior exploration and exploitation capabilities, enabling systematic hyperparameter tuning and delivering a balanced engineering approach that combines predictive performance with resource efficiency.

Keywords

Main Subjects

[1] K. Kamble and J. Sengupta, "A comprehensive survey on emotion recognition based on electroencephalograph (EEG) signals," Multimedia Tools and Applications, vol. 82, no. 18, pp. 27269–27304, 2023.
[2] D. W. Prabowo, H. A. Nugroho, N. A. Setiawan, and J. Debayle, "A systematic literature review of emotion recognition using EEG signals," Cognitive Systems Research, vol. 82, p. 1452, 2023.
[3] M. Jafari, et al., "Emotion recognition in EEG signals using deep learning methods: A review," Computers in Biology and Medicine, vol. 165, p. 107450, 2023.
[4] S. K. Khare, V. Blanes-Vidal, E. S. Nadimi, and U. R. Acharya, "Emotion recognition and artificial intelligence: A systematic review (2014–2023) and research recommendations," Information Fusion, vol. 102, p. 102019, 2024.
[5] M. Kaveh and M. S. Mesgari, "Application of meta-heuristic algorithms for training neural networks and deep learning architectures: A comprehensive review," Neural Processing Letters, vol. 55, pp. 4519–4622, 2022.
[6] Z. Gao, Y. Li, Y. Yang, X. Wang, N. Dong, and H.-D. Chiang, "A GPSO-optimized convolutional neural networks for EEG-based emotion recognition," Neurocomputing, vol. 380, pp. 225–235, 2020.
[7] M. R. Falahzadeh, F. Farokhi, A. Harimi, et al., "Deep convolutional neural network and gray wolf optimization algorithm for speech emotion recognition," Circuits Systems and Signal Processing, vol. 42, pp. 449–492, 2023.
[8] Y. Yang, Q. Wu, Y. Fu, and X. Chen, "Continuous convolutional neural network with 3D input for EEG-based emotion recognition," in ICONIP , vol. 11307, pp. 433–443, 2018.
[9] S. Hwang, K. Hong, G. Son, and H. Byun, "Learning CNN features from DE features for EEG-based emotion recognition," Pattern Analysis and Applications, vol. 23, pp. 1323–1335, 2019.
[10] M. Abd Elaziz, A. Dahou, L. Abualigah, L. Yu, M. Alshinwan, A. M. Khasawneh, and S. Lu, "Advanced metaheuristic optimization techniques in applications of deep neural networks: A review," Neural Computing and Applications, vol. 33, pp. 14079–14099, 2021.
[11] A. K. Mishra, S. K. Singh, and A. K. Sahoo, "Evolution of convolutional neural network (CNN): Compute vs memory bandwidth for edge AI," arXiv:2311.12816, 2023.
[12] Z. Zhang, S. Zhong, and Y. Liu, "TorchEEGEMO: A deep learning toolbox towards EEG-based emotion recognition," Expert Systems with Applications, vol. 249, 123550, 2024.
[13] S. Mirjalili and A. Lewis, "The Whale Optimization Algorithm," Advances in Engineering Software, vol. 95, pp. 51–67, 2016.
[14] S. Mirjalili, S. M. Mirjalili, and A. Lewis, "Grey Wolf Optimizer," Advances in Engineering Software, vol. 69, pp. 46–61, 2014.
[15] S. B. Lee, H. H. Chang, and C. H. Chuang, "Investigating Critical Frequency Bands and Channels for EEG-Based Emotion Recognition," in ACII, Xi'an, China, pp. 1–6, 2015.
[16] R. Salgotra, P. Sharma, S. Raju, and A. H. Gandomi, "A Contemporary Systematic Review on Meta-heuristic Optimization Algorithms with Their MATLAB and Python Code Reference," Archives of Computational Methods in Engineering, vol. 31, pp. 1749–1822, 2024.
[17] S. Mirjalili, "Grey Wolf Optimizer (GWO)," https://seyedalimirjalili.com/gwo. Access Date: Dec. 2025.
[18] S. Mirjalili, "Whale Optimization Algorithm (WOA)," https://seyedalimirjalili.com/woa. Access Date: Dec. 2025.
[19] V. J. Lawhern, A. J. Solon, N. R. Waytowich, S. M. Gordon, C. P. Hung, and B. J. Lance, "EEGNet: A compact convolutional neural network for EEG-based brain-computer interfaces," Journal of Neural Engineering, vol. 15, no. 5, 056013, 2018.

[20] R. Mane, E. Chew, K. Chua, et al., "FBCNet: A multi-view convolutional neural network for brain-computer interface," arXiv:2104.01233, 2021.
[21] Y. Ding, N. Robinson, S. Zhang, et al., "TSception: Capturing temporal dynamics and spatial asymmetry from EEG for emotion recognition," arXiv:2104.02935, 2021.
[22] W. Li, W. Huan, B. Hou, Y. Tian, Z. Zhang, and A. Song, "Can emotion be transferred?—A review on transfer learning for EEG-based emotion recognition," IEEE Transactions on Cognitive and Developmental Systems, vol. 14, no. 3, pp. 833–846, 2021.
[23] Y. Ding, N. Robinson, Q. Zeng, and C. Guan, "LGGNet: Learning from local global-graph representations for brain-computer interface," arXiv:2105.02786, 2021.
[24] A. Vaswani, N. Shazeer, N. Parmar, J. Uszkoreit, L. Jones, A. N. Gomez, et al., "Attention Is All You Need," Advances in Neural Information Processing Systems, vol. 30, 2017.
[25] A. Dosovitskiy, L. Beyer, A. Kolesnikov, D. Weissenborn, X. Zhai, T. Unterthiner, et al., "An Image Is Worth 16×16 Words: Transformers for Image Recognition at Scale," arXiv:2010.11929, 2020.
[26] L. Beyer, X. Zhai, and A. Kolesnikov, "Better Plain ViT Baselines for ImageNet-1k," arXiv:2205.01580, 2022.
[27] A. Arjun, A. S. Rajpoot, and M. R. Panicker, "Introducing attention mechanism for EEG signals: Emotion recognition with vision transformers," in EMBC, pp. 5723–5726, 2021.
[28] M. Esmaeiili and K. Kiani, "Enhancing Emotion Classification via EEG Signal Frame Selection," Journal of Artificial Intelligence and Data Mining, vol. 12, no. 1, pp. 83–93, 2024.