Multi-Class Sleep Stage Analysis and Adaptive Pattern Recognition
Open accessAbstract
Multimodal signal analysis based on sophisticated sensors, efficient communication systems and fast parallel processing methods has a rapidly increasing range of multidisciplinary applications. The present paper is devoted to pattern recognition, machine learning, and the analysis of sleep stages in the detection of sleep disorders using polysomnography (PSG) data, including electroencephalography (EEG), breathing (Flow), and electro-oculogram (EOG) signals. The proposed method is based on the classification of selected features by a neural network system with sigmoidal and softmax transfer functions using Bayesian methods for the evaluation of the probabilities of the separate classes. The application is devoted to the analysis of the sleep stages of 184 individuals with different diagnoses, using EEG and further PSG signals. Data analysis points to an average increase of the length of the Wake stage by 2.7% per 10 years and a decrease of the length of the Rapid Eye Movement (REM) stages by 0.8% per 10 years. The mean classification accuracy for given sets of records and single EEG and multimodal features is 88.7% ( standard deviation, STD: 2.1) and 89.6% (STD:1.9), respectively. The proposed methods enable the use of adaptive learning processes for the detection and classification of health disorders based on prior specialist experience and man–machine interaction.
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The system's mean classification accuracy was 88.7% for multiclass sleep stage analysis using ANN with sigmoidal and softmax transfer functions and Bayesian network.
“The system’s mean classification accuracy was 88.7% [189].”
From Review of Wearable Devices and Data Collection Considerations for Connected Health (2021) · cites this paper as [189]
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1 retracted
Dursun, M., Özşen, S., Yücelbaş, C., Yücelbaş, Ş., Tezel, G., Küççüktürk, S., & Yosunkaya, Ş. (2016) · Neural Computing and Applications · doi:10.1007/s00521-016-2578-z · Cited by 24 · see citing works
RetractedSanei, S., & Chambers, J. A. (2007) · Wiley eBooks · doi:10.1002/9780470511923 · Cited by 1,553 · see citing works
Chambon, S., Galtier, M. N., Arnal, P. J., Wainrib, G., & Gramfort, A. (2018) · IEEE Transactions on Neural Systems and Rehabilitation Engineering · doi:10.1109/tnsre.2018.2813138 · Cited by 632 · see citing works
A convolutional neural network for sleep stage scoring from raw single-channel EEG
Sors, A., Bonnet, S., Mirek, S., Vercueil, L., & Payen, J. (2018) · Biomedical Signal Processing and Control · doi:10.1016/j.bspc.2017.12.001 · Cited by 425 · see citing works
Sleep Stage Classification Using EEG Signal Analysis: A Comprehensive Survey and New Investigation
Aboalayon, K. A. I., Faezipour, M., Almuhammadi, W. S., & Moslehpour, S. (2016) · Entropy · doi:10.3390/e18090272 · Cited by 387 · see citing works
Zhu, G., Li, Y., & Wen, P. P. (2014) · IEEE Journal of Biomedical and Health Informatics · doi:10.1109/jbhi.2014.2303991 · Cited by 381 · see citing works
A comparative review on sleep stage classification methods in patients and healthy individuals
Boostani, R., Karimzadeh, F., & Nami, M. (2016) · Computer Methods and Programs in Biomedicine · doi:10.1016/j.cmpb.2016.12.004 · Cited by 319 · see citing works
Lajnef, T., Chaibi, S., Ruby, P. M., Aguera, P., Eichenlaub, J., Samet, M., Kachouri, A., & Jerbi, K. (2015) · Journal of Neuroscience Methods · doi:10.1016/j.jneumeth.2015.01.022 · Cited by 317 · see citing works
Automatic sleep stage recurrent neural classifier using energy features of EEG signals
Hsu, Y., Yang, Y., Wang, J.-S., & Hsu, C. (2012) · Neurocomputing · doi:10.1016/j.neucom.2012.11.003 · Cited by 298 · see citing works
Multi-class pattern classification using neural networks
Ou, G., & Murphey, Y. L. (2006) · Pattern Recognition · doi:10.1016/j.patcog.2006.04.041 · Cited by 289 · see citing works
Şen, B., Peker, M., Çavuşoğlu, A., & Çelebi, F. V. (2014) · Journal of Medical Systems · doi:10.1007/s10916-014-0018-0 · Cited by 282 · see citing works
Espiritu, J. R. D. (2007) · Clinics in Geriatric Medicine · doi:10.1016/j.cger.2007.08.007 · Cited by 276 · see citing works
Li, K., Pan, W., Li, Y., Jiang, Q. Y., & Liu, G. (2018) · Neurocomputing · doi:10.1016/j.neucom.2018.03.011 · Cited by 255 · see citing works
Song, C., Liu, K., Zhang, X., Chen, L., & Xian, X. (2015) · IEEE Transactions on Biomedical Engineering · doi:10.1109/tbme.2015.2498199 · Cited by 253 · see citing works
Sleep Stage Classification Using Unsupervised Feature Learning
Längkvist, M., Karlsson, L., & Loutfi, A. (2012) · Advances in Artificial Neural Systems · doi:10.1155/2012/107046 · Cited by 248 · see citing works
Automatic sleep stages classification based on iterative filtering of electroencephalogram signals
Sharma, R. K., Pachori, R. B., & Upadhyay, A. B. (2017) · Neural Computing and Applications · doi:10.1007/s00521-017-2919-6 · Cited by 202 · see citing works
Adaptive Processing of Brain Signals
Sanei, S. (2013) · Wiley eBooks · doi:10.1002/9781118622162 · Cited by 189 · see citing works
EEG Sleep Stages Classification Based on Time Domain Features and Structural Graph Similarity
Diykh, M., Li, Y., & Wen, P. P. (2016) · IEEE Transactions on Neural Systems and Rehabilitation Engineering · doi:10.1109/tnsre.2016.2552539 · Cited by 180 · see citing works
Sleep stage classification with ECG and respiratory effort
Fonseca, P. M., Long, X., Radha, M., Haakma, R., Aarts, R. M., & Rolink, J. (2015) · Physiological Measurement · doi:10.1088/0967-3334/36/10/2027 · Cited by 168 · see citing works
Sensitivity Versus Accuracy in Multiclass Problems Using Memetic Pareto Evolutionary Neural Networks
Fernández, J. C. F., Martinez, F. J., Hervás‐Martínez, C., & Gutiérrez, P. A. (2010) · IEEE Transactions on Neural Networks · doi:10.1109/tnn.2010.2041468 · Cited by 161 · see citing works
Estimation of Sleep Stages by an Artificial Neural Network Employing EEG, EMG and EOG
Tagluk, M. E., Sezgın, N., & Akın, M. (2009) · Journal of Medical Systems · doi:10.1007/s10916-009-9286-5 · Cited by 128 · see citing works
Multi-class ROC analysis from a multi-objective optimisation perspective
Everson, R., & Fieldsend, J. E. (2005) · Pattern Recognition Letters · doi:10.1016/j.patrec.2005.10.016 · Cited by 122 · see citing works
Rodríguez-Sotelo, J. L., Osorio-Forero, A., Jiménez-Rodríguez, A., Cuesta–Frau, D., Cirugeda, E., & Peluffo-Ordóñez, D. H. (2014) · Entropy · doi:10.3390/e16126573 · Cited by 121 · see citing works
Procházka, A., Vyšata, O., Vališ, M., Ťupa, O., Schätz, M., & Mařı́k, V. (2015) · Digital Signal Processing · doi:10.1016/j.dsp.2015.05.011 · Cited by 112 · see citing works
Self-citationA transition-constrained discrete hidden Markov model for automatic sleep staging
Pan, S.-T., Kuo, C., Zeng, J.-H., & Liang, S. (2012) · BioMedical Engineering OnLine · doi:10.1186/1475-925x-11-52 · Cited by 86 · see citing works
Classification of Sleep Stages Using Multi-wavelet Time Frequency Entropy and LDA
Lweesy, K. Y., Khasawneh, N., Fraiwan, M., Wenz, H., Dickhaus, H., & Fraiwan, L. (2010) · Methods of Information in Medicine · doi:10.3414/me09-01-0054 · Cited by 85 · see citing works
Microsoft Kinect Visual and Depth Sensors for Breathing and Heart Rate Analysis
Procházka, A., Schätz, M., Vyšata, O., & Vališ, M. (2016) · Sensors · doi:10.3390/s16070996 · Cited by 85 · see citing works
Self-citationApproximating the multiclass ROC by pairwise analysis
Landgrebe, T. C. W., & Duin, R. P. W. (2007) · Pattern Recognition Letters · doi:10.1016/j.patrec.2007.05.001 · Cited by 83 · see citing works
Looney, D., Goverdovsky, V., Rosenzweig, I., Morrell, M. J., & Mandic, D. P. (2016) · Annals of the American Thoracic Society · doi:10.1513/annalsats.201605-342bc · Cited by 78 · see citing works
Özşen, S. (2012) · Neural Computing and Applications · doi:10.1007/s00521-012-1065-4 · Cited by 63 · see citing works
Peker, M. (2016) · Neurocomputing · doi:10.1016/j.neucom.2016.04.049 · Cited by 56 · see citing works
Non-invasive analysis of sleep patterns via multimodal sensor input
Metsis, V., Kosmopoulos, D., Athitsos, V., & Makedon, F. S. (2012) · Personal and Ubiquitous Computing · doi:10.1007/s00779-012-0623-1 · Cited by 51 · see citing works
A hierarchical classification system for sleep stage scoring via forehead EEG signals
Huang, C.-S., Lin, C., Ko, L., Liu, S.-Y., Sua, T.-P., & Lin, C. (2013) · IEEE Symposium on Computational Intelligence, Cognitive Algorithms, Mind, and Brain (CCMB) · doi:10.1109/ccmb.2013.6609157 · Cited by 38 · see citing works
Screening for REM sleep behavior disorder in the general population
Bušková, J., Ibarburu, V., Šonka, K., & Růžička, E. (2016) · Sleep Medicine · doi:10.1016/j.sleep.2016.07.003 · Cited by 38 · see citing works
Monitoring of Weekly Sleep Pattern Variations at Home with a Contactless Biomotion Sensor
Hashizaki, M., Nakajima, H., & Kume, K. (2015) · Sensors · doi:10.3390/s150818950 · Cited by 37 · see citing works
Extraction of breathing features using MS Kinect for sleep stage detection
Procházka, A., Schätz, M., Centonze, F., Kuchyňka, J., Vyšata, O., & Vališ, M. (2016) · Signal Image and Video Processing · doi:10.1007/s11760-016-0897-2 · Cited by 32 · see citing works
Self-citationDiscrimination of axonal neuropathy using sensitivity and specificity statistical measures
Procházka, A., Vyšata, O., Ťupa, O., Yadollahi, M., & Vališ, M. (2014) · Neural Computing and Applications · doi:10.1007/s00521-014-1622-0 · Cited by 26 · see citing works
Self-citationAge and gender dependency of physiological networks in sleep
Krefting, D., Jansen, C., Penzel, T., Han, F., & Kantelhardt, J. W. (2017) · Physiological Measurement · doi:10.1088/1361-6579/aa614e · Cited by 12 · see citing works
An Adaptive Filtering Approach Using Supervised SSA for Identification of Sleep Stages From EEG
Kouchaki, S., Eftaxias, K., & Sanei, S. (2014) · Nottingham Trent University's Institutional Repository (Nottingham Trent Repository) · Cited by 10 · see citing works
Electroencephalography Analysis Using Neural Network and Support Vector Machine during Sleep
Lee, J., & Yoo, S. K. (2013) · Engineering · doi:10.4236/eng.2013.55b018 · Cited by 9 · see citing works
Automatic Sleep Stages Detection Based on EEG Signals Using Combination of Classifiers
Kianzad, R., & Kordy, H. M. (2013) · DOAJ (DOAJ: Directory of Open Access Journals) · doi:10.22061/jecei.2013.30 · Cited by 8 · see citing works
Age-dependent complex noise fluctuations in the brain
Mareš, J., Vyšata, O., Procházka, A., & Vališ, M. (2013) · Physiological Measurement · doi:10.1088/0967-3334/34/10/1269 · Cited by 7 · see citing works
Self-citationCharacterizing Sleep Stages by the Fractal Dimensions of Electroencephalograms
Chen, J.-Y. (2017) · Biostatistics and Biometrics Open Access Journal · doi:10.19080/bboaj.2017.02.555584 · Cited by 5 · see citing works
A single-trial toolbox for advanced sleep polysomnographic preprocessing
Chaparro-Vargas, R., & Cvetković, D. (2013) · doi:10.1109/embc.2013.6610877 · Cited by 4 · see citing works
Adaptive segmentation of multimodal polysomnography data for sleep stages detection
Procházka, A., Kuchyňka, J., Yadollahi, M., Araujo, C. P. S., & Vyšata, O. (2017) · IEEE International Conference on Digital Signal Processing (DSP) · doi:10.1109/icdsp.2017.8096108 · Cited by 3 · see citing works
Self-citationCharacterizing Sleep Stages by the Fractal Dimensions of Electroencephalograms
Liaw, S.-S., & Chen, J.-Y. (n.d.) · RePEc: Research Papers in Economics · Cited by 3 · see citing works
Sleep Stages Classification Using Neural Network with Single Channel EEG
Venkatesh, K., Poonguzhali, S., Mohanavelu, K., & Adalarasu, K. (2014) · Cited by 1 · see citing works
Flagged first, then by citations
Research works printed but not linked: 2
- Looney, D.; Goverdovsky, V.; Rosenzweig, I.; Morrell, M.; Mandic, D. Wearable In-Ear Encephalography Sensor for Monitoring Sleep. Ann. Am. Thorac. Soc. 2016, 13, 2230-2233.
- Ahuja, Y.; Yadav, S. Multiclass classification and support vector machine. Glob. J. Comput. Sci. Technol. 2012, 12, 15-19.
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Review of Wearable Devices and Data Collection Considerations for Connected Health
Vijayan, V., Connolly, J. P., Condell, J., McKelvey, N., & Gardiner, P. (2021) · Sensors · doi:10.3390/s21165589 · Cited by 435 · see citing works
Clinical applications of artificial intelligence in sleep medicine: A sleep clinician’s perspective
Bandyopadhyay, A., & Goldstein, C. (2023) · Sleep And Breathing · doi:10.1007/s11325-022-02592-4 · Cited by 108 · see citing works
Computational Sleep Behavior Analysis: A Survey
Fallmann, S., & Chen, L. (2019) · IEEE Access · doi:10.1109/access.2019.2944801 · Cited by 58 · see citing works
Comparative analysis of different characteristics of automatic sleep stages
Zhao, D., Wang, Y., Wang, Q., & Wang, X. (2019) · Computer Methods and Programs in Biomedicine · doi:10.1016/j.cmpb.2019.04.004 · Cited by 58 · see citing works
Hybrid CNN-LSTM Network for Real-Time Apnea-Hypopnea Event Detection Based on IR-UWB Radar
Kwon, H. B., Son, D., Lee, D., Yoon, H., Lee, M. H., Lee, Y. J., Choi, S. H., & Park, K. S. (2021) · IEEE Access · doi:10.1109/access.2021.3081747 · Cited by 55 · see citing works
Procházka, A., Vyšata, O., & Mařı́k, V. (2021) · IEEE Signal Processing Magazine · doi:10.1109/msp.2021.3058634 · Cited by 50 · see citing works
Self-citationSatti, A. T., Kim, J., Yi, E.-S., Cho, H.-Y., & Cho, S. (2021) · Sensors · doi:10.3390/s21155091 · Cited by 46 · see citing works
Jarchi, D., Andreu-Pérez, J., Kiani, M., Vyšata, O., Kuchyňka, J., Procházka, A., & Sanei, S. (2020) · Sensors · doi:10.3390/s20092594 · Cited by 44 · see citing works
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Self-citationDeep learning approach for ECG-based automatic sleep state classification in preterm infants
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Automatic sleep scoring: A deep learning architecture for multi-modality time series
Yan, R., Li, F., Zhou, D., Ristaniemi, T., & Cong, F. (2020) · Journal of Neuroscience Methods · doi:10.1016/j.jneumeth.2020.108971 · Cited by 34 · see citing works
Wara, T. U., Fahad, A. H., Das, A. S., & Shawon, M. M. H. (2025) · Heliyon · doi:10.1016/j.heliyon.2025.e43576 · Cited by 27 · see citing works
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Motin, M. A., Karmakar, C., Palaniswami, M. S., & Penzel, T. (2020) · Physiological Measurement · doi:10.1088/1361-6579/ab9482 · Cited by 26 · see citing works
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Self-citation
- Authors
- Procházka, A., Kuchyňka, J., Vyšata, O., Cejnar, P., Vališ, M., & Mařík, V.
- Affiliations
- Czech Technical University in Prague (CZ)
- Charles University (CZ)
- University of Chemistry and Technology, Prague (CZ)
- Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, 166 36 Prague, Czech Republic
- Corresponding author
- Procházka, Aleš
- Venue
- Applied Sciences
- Publisher
- MDPI AG
- Published
- 2018-05-01
- Volume
- 8
- Issue
- 5
- Pages
- 697
- ISSN
- 2076-3417 (ISSN-L)
- OpenAlex
- W2802412756
- Cited by
- 32
- References
- 47
- Citations by year
- 2026: 1 · 2025: 2 · 2022: 3 · 2021: 9 · 2020: 8 · 2019: 8 · 2018: 1
- FWCI
- 3.87
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- Applied Sciences (publishedVersion, cc-by)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Funders
- Univerzita Karlova v Praze (00179906, PROGRES Q40, FN HK 00179906)
- Fakultní nemocnice Hradec Králové (00179906)
- Ministerstvo Zdravotnictví Ceské Republiky (00179906], PROGRES Q40, FNHK00179906)
- Topics
- Life Sciences › Neuroscience › Cognitive Neuroscience › EEG and Brain-Computer Interfaces
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
- Health Sciences › Medicine › Physiology › Obstructive Sleep Apnea Research
- Keywords
- sleep stage classification, polysomnography, EEG, sleep disorders, neural network classification, Bayesian classification, adaptive learning, REM sleep, electrooculogram, respiratory signals, age-related sleep changes
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