Abstract
The motor movement performed by different body parts affects the synaptic potential at different brain cortices, which can be observed by the electroencephalogram (EEG) signal. The recorded EEG signals can be used to decode the imagined motor task. The EEG signals are non-stationary and transient and contain time, frequency, and space information. Extracting this information and processing them with the latest machine learning and deep learning algorithms can be useful for brain–computer interfacing and other human–machine interaction techniques. EEG signal contains negative values. Hence, nonnegative matrix factorization can be used to provide a meaningful explanation of information within EEG signals. Sparseness in feature vectors is another essential factor to consider while identifying the structures in an input signal. In this work, we propose a novel motor imagery classification model that extracts the weights for predefined motor imagery features from EEG signals and classifies them using a convolution neural network (CNN). Sparse nonnegative matrix factorization is used to extract the fundamental feature vectors for different motor imagery events, which are further used to extract the combined weight matrix of unknown motor imagery events. The designed CNN classifies the extracted weight matrix in the corresponding classes. The acquired EEG signals from all the channels are processed simultaneously using the CNN, which helps extract spatial information from the signals. BCI Competition IV dataset IIa and BCI Competition III dataset IVa are used to validate the proposed method. The proposed method has been compared with existing methods and validates their superiority in terms of average accuracy. The classification accuracy for two types and four types of motor imagery signals is 99.53% and 94.58%, respectively. Empirical results show that EEG signals’ sparseness characteristics can be considered an effective feature for motor imagery classification.
Similar content being viewed by others
Data Availability
Data available on request from the authors.
References
Bashashati H, Ward RK, Bashashati A (2016) User-customized brain computer interfaces using Bayesian optimization. J Neural Eng 13(2):026001
Batula AM, Mark JA, Kim YE, Ayaz H (2017) Comparison of brain activation during motor imagery and motor movement using FNIRS. Comput Intell Neurosci 2017
Brunner C, Leeb R, Müller-Putz G, Schlögl A, Pfurtscheller G (2008) Bci competition 2008–graz data set a. Institute for Knowledge Discovery (Laboratory of Brain-Computer Interfaces), Graz University of Technology 16:1–6
Chacon-Murguia MI, Olivas-Padilla BE, Ramirez-Quintana J (2020) A new approach for multiclass motor imagery recognition using pattern image features generated from common spatial patterns. SIViP 14(5):915–923
Chaudhary P, Agrawal R (2020) Non-dyadic wavelet decomposition for sensory-motor imagery EEG classification. Brain–Comput Interfaces 7(1–2):11–21
Chaudhary P, Agrawal R (2021) Sensory motor imagery EEG classification based on non-dyadic wavelets using dynamic weighted majority ensemble classification. Intell Decis Technol 15(1):33–43
Chaudhary S, Taran S, Bajaj V, Sengur A (2019) Convolutional neural network based approach towards motor imagery tasks EEG signals classification. IEEE Sens J 19(12):4494–4500
Dong E, Li C, Li L, Du S, Belkacem AN, Chen C (2017) Classification of multi-class motor imagery with a novel hierarchical SVM algorithm for brain–computer interfaces. Med Biol Eng Comput 55(10):1809–1818
Dornhege G, Blankertz B, Curio G, Muller KR (2004) Boosting bit rates in noninvasive EEG single-trial classifications by feature combination and multiclass paradigms. IEEE Trans Biomed Eng 51(6):993–1002
Gupta MD, Xiao J (2011) Non-negative matrix factorization as a feature selection tool for maximum margin classifiers. In: CVPR 2011. IEEE, pp 2841–2848
Hoyer PO (2004) Non-negative matrix factorization with sparseness constraints. J Mach Learn Res 5(9):1
Jung Y, Hu J (2015) Ak-fold averaging cross-validation procedure. J Nonparamet Stat 27(2):167–179
Kevric J, Subasi A (2017) Comparison of signal decomposition methods in classification of EEG signals for motor-imagery BCI system. Biomed Signal Process Control 31:398–406
Khan GH, Hashmi MA, Awais MM, Khan NA, Ahmad RB (2020) High performance multi-class motor imagery eeg classification. In: BIOSIGNALS, pp 149–155
Krishna DH, Pasha I, Savithri TS (2016) Classification of EEG motor imagery multi class signals based on cross correlation. Procedia Computer Science 85:490–495
Kwon K, Shin JW, Kim NS (2015) Target source separation based on discriminative nonnegative matrix factorization incorporating cross-reconstruction error. IEICE Trans Inf Syst 98(11):2017–2020
Lee D, Seung HS (2000) Algorithms for non-negative matrix factorization. Adv Neural Inf Process Syst 13:1
Lee H, Choi S (2009) Group nonnegative matrix factorization for EEG classification. In: Artificial intelligence and statistics. PMLR, pp 320–327
Lee H, Cichocki A, Choi S (2006) Nonnegative matrix factorization for motor imagery EEG classification. In: International conference on artificial neural networks. Springer, pp 250–259
Lee H, Cichocki A, Choi S (2009) Kernel nonnegative matrix factorization for spectral EEG feature extraction. Neurocomputing 72(13–15):3182–3190
Liu M, Wang J, Zheng C, Yan N (2006) Using non-negative matrix fact factorization to extract attention-related EEG features. Society of China
Liu S, Bai W, Srivastava G, Machado JA (2020) Property of self-similarity between baseband and modulated signals. Mobile Networks Appl 25(4):1537–1547
Ma X, Wang D, Liu D, Yang J (2020) Dwt and cnn based multi-class motor imagery electroencephalographic signal recognition. J Neural Eng 17(1):016073
Phadikar S, Sinha N, Ghosh R (2022) Neural network-based feature extraction for multi-class motor imagery classification. arXiv preprint arXiv:2201.01468
Rashid M, Bari BS, Hasan MJ, Razman MAM, Musa RM, Ab Nasir AF, Majeed APA (2021) The classification of motor imagery response: an accuracy enhancement through the ensemble of random subspace k-nn. PeerJ Comput Sci 7:e374
Sadiq MT, Yu X, Yuan Z, Aziz MZ (2020) Identification of motor and mental imagery EEG in two and multiclass subject-dependent tasks using successive decomposition index. Sensors 20(18):5283
Sakhavi S, Guan C, Yan S (2018) Learning temporal information for brain–computer interface using convolutional neural networks. IEEE Trans Neural Netw Learn Syst 29(11):5619–5629
Siuly Li Y, Wen P (2013) Identification of motor imagery tasks through CC–LR algorithm in brain computer interface. Int J Bioinform Res Appl 9(2):156–172
Siuly S, Li Y (2012) Improving the separability of motor imagery EEG signals using a cross correlation-based least square support vector machine for brain-computer interface. IEEE Trans Neural Syst Rehabil Eng 20(4):526–538
Siuly S, Li Y (2015) Discriminating the brain activities for brain-computer interface applications through the optimal allocation-based approach. Neural Comput Appl 26(4):799–811
Stojanović O, Kuhlmann L, Pipa G (2020) Predicting epileptic seizures using nonnegative matrix factorization. PLoS ONE 15(2):e0228025
Sugi T, Kawana F, Nakamura M (2009) Automatic EEG arousal detection for sleep apnea syndrome. Biomed Signal Process Control 4(4):329–337
Suk HI, Lee SW (2011) Subject and class specific frequency bands selection for multiclass motor imagery classification. Int J Imaging Syst Technol 21(2):123–130
Taran S, Bajaj V, Sharma D, Siuly S, Sengur A (2018) Features based on analytic IMF for classifying motor imagery EEG signals in BCI applications. Measurement 116:68–76
Tosun M, Çetin O (2022) A new phase-based feature extraction method for four-class motor imagery classification. SIViP 16(1):283–290
Varshney YV, Abbasi Z, Abidi M, Farooq O, Upadhyaya P (2017) Snmf based speech denoising with wavelet decomposed signal selection. In: 2017 International Conference on Wireless Communications, Signal Processing and Networking (WiSPNET). IEEE, pp 2603–2606
Verma NK, Rao LVS, Sharma SK (2014) Motor imagery eeg signal classification on dwt and crosscorrelated signal features. In: 2014 9th International Conference on Industrial and Information Systems (ICIIS). IEEE, pp 1–6
Zhou T, Kang J, Cong F, Li X (2020) Stability-driven non-negative matrix factorization-based approach for extracting dynamic network from resting-state eeg. Neurocomputing 389:123–131
Funding
This article did not receive any Funding from any External Sources.
Author information
Authors and Affiliations
Contributions
P.C. contributed to conceptualization, methodology, software, data curation, validation, investigation, visualization, and writing—original draft. Y.V. contributed to supervision, conceptualization, methodology, investigation, and writing—review and editing. G.S. contributed to methodology, validation, and writing—review and editing. S.B. contributed to methodology and writing—review and editing.
Corresponding authors
Ethics declarations
Conflict of Interest
The authors have no Conflicts of Interest to declare for this manuscript.
Ethical Approval
For this type of study formal consent was not required. This manuscript does not contain any studies with human participants or animals performed by any of the authors.
Code Availability
Code available on request from the authors.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Chaudhary, P., Varshney, Y.V., Srivastava, G. et al. Motor imagery classification using sparse nonnegative matrix factorization and convolutional neural networks. Neural Comput & Applic 36, 213–223 (2024). https://doi.org/10.1007/s00521-022-07861-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00521-022-07861-7