{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T01:19:48Z","timestamp":1789348788251,"version":"build-2803163510"},"reference-count":43,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,3,22]],"date-time":"2025-03-22T00:00:00Z","timestamp":1742601600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>This research explored the integration of the real-time machine learning classification of motor imagery data with a brain\u2013machine interface, leveraging prefabricated exoskeletons and an EEG headset integrated with virtual reality (VR). By combining these technologies, the study aimed to develop practical and scalable therapeutic applications for rehabilitation and daily motor training. The project showcased an optimized system designed to assess and train cognitive\u2013motor functions in elderly individuals. Key innovations included a motor imagery EEG acquisition protocol for data classification and a machine learning framework leveraging deep learning with a wavelet packet transform for feature extraction. Comparative analyses were conducted with traditional models such as Support Vector Machines (SVMs), Convolutional Neural Networks (CNNs), and Long Short-Term Memory (LSTM) networks. The performance was further enhanced through a random hyperparameter search, optimizing feature extraction and learning parameters to achieve high classification accuracy (89.23%). A novel VR fishing game was developed to dynamically respond to EEG outputs, enabling the performance of interactive motor imagery tasks in coordination with upper limb exoskeleton arms. While clinical testing is ongoing, the system demonstrates potential for increasing ERD\/ERS polarization rates in alpha and beta waves among elderly users after several weeks of training. This integrated approach offers a tangible step forward in creating effective, user-friendly solutions for motor function rehabilitation.<\/jats:p>","DOI":"10.3390\/bioengineering12040331","type":"journal-article","created":{"date-parts":[[2025,3,24]],"date-time":"2025-03-24T07:46:50Z","timestamp":1742802410000},"page":"331","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Deep Learning-Enhanced Motor Training: A Hybrid VR and Exoskeleton System for Cognitive\u2013Motor Rehabilitation"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-2987-6557","authenticated-orcid":false,"given":"Kathya P.","family":"Acu\u00f1a Luna","sequence":"first","affiliation":[{"name":"Mirai Innovation Research Institute, Osaka 559-0034, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-6398-0722","authenticated-orcid":false,"given":"Edgar Rafael","family":"Hernandez-Rios","sequence":"additional","affiliation":[{"name":"Mirai Innovation Research Institute, Osaka 559-0034, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Victor","family":"Valencia","sequence":"additional","affiliation":[{"name":"Mirai Innovation Research Institute, Osaka 559-0034, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlos","family":"Trenado","sequence":"additional","affiliation":[{"name":"Institute for the Future of Education Europe (IFE), 48014 Bilbao, Spain"},{"name":"Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich Heine University, 40225 D\u00fcsseldorf, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Pe\u00f1aloza","sequence":"additional","affiliation":[{"name":"Mirai Innovation Research Institute, Osaka 559-0034, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Tokg\u00f6z, P., Stampa, S., W\u00e4hnert, D., Vordemvenne, T., and Dockweiler, C. (2022). Virtual Reality in the Rehabilitation of Patients with Injuries and Diseases of Upper Extremities. Healthcare, 10.","DOI":"10.3390\/healthcare10061124"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"650","DOI":"10.1080\/13803390701625821","article-title":"Assessment of spatial attention and neglect with a virtual wheelchair navigation task","volume":"30","author":"Buxbaum","year":"2008","journal-title":"J. Clin. Exp. Neuropsychol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"411","DOI":"10.7205\/MILMED-D-09-00081","article-title":"Driving rehabilitation for military personnel recovering from traumatic brain injury using virtual reality driving simulation: A feasibility study","volume":"175","author":"Cox","year":"2010","journal-title":"Mil. Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1089\/g4h.2018.0029","article-title":"Xbox 360 Kinect Cognitive Games Improve Slowness, Complexity of EEG, and Cognitive Functions in Subjects with Mild Cognitive Impairment: A Randomized Control Trial","volume":"8","author":"Amjad","year":"2019","journal-title":"Games Health J."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Liao, Y.Y., Chen, I.H., Lin, Y.J., Chen, Y., and Hsu, W.C. (2019). Effects of Virtual Reality-Based Physical and Cognitive Training on Executive Function and Dual-Task Gait Performance in Older Adults with Mild Cognitive Impairment: A Randomized Control Trial. Front. Aging Neurosci., 11.","DOI":"10.3389\/fnagi.2019.00162"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"663","DOI":"10.1080\/13607863.2022.2076202","article-title":"The effect of virtual reality on executive function in older adults with mild cognitive impairment: A systematic review and meta-analysis","volume":"27","author":"Yu","year":"2023","journal-title":"Aging Ment. Health"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Kim, H., Kim, D.J., Kim, S., Chung, W.H., Park, K.A., Kim, J.D.K., Kim, D., Kim, M.J., Kim, K., and Jeon, H.J. (2021). Effect of Virtual Reality on Stress Reduction and Change of Physiological Parameters Including Heart Rate Variability in People with High Stress: An Open Randomized Crossover Trial. Front. Psychiatry, 12.","DOI":"10.3389\/fpsyt.2021.614539"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Collins, J., Regenbrecht, H., Langlotz, T., Can, Y.S., Ersoy, C., and Butson, R. (2019, January 14\u201318). Measuring cognitive load and insight: A methodology exemplified in a virtual reality learning context. Proceedings of the 2019 IEEE International Symposium on Mixed and Augmented Reality (ISMAR), Beijing, China.","DOI":"10.1109\/ISMAR.2019.00033"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1614","DOI":"10.1109\/TNSRE.2020.2998123","article-title":"Observing actions through immersive virtual reality enhances motor imagery training","volume":"28","author":"Choi","year":"2020","journal-title":"IEEE Trans. Neural Syst. Rehabil. Eng."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Vourvopoulos, A., Jorge, C., Abreu, R., Figueiredo, P., and Fernandes, J. (2019). Efficacy and Brain Imaging Correlates of an Immersive Motor Imagery BCI-Driven VR System for Upper Limb Motor Rehabilitation: A Clinical Case Report. Front. Hum. Neurosci., 13.","DOI":"10.3389\/fnhum.2019.00244"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"McGibbon, C.A., Sexton, A., and Gryfe, P. (2024). Exercising with a robotic exoskeleton can improve memory and gait in people with Parkinson\u2019s disease by facilitating progressive exercise intensity. Sci. Rep., 14.","DOI":"10.1038\/s41598-024-54200-y"},{"key":"ref_12","first-page":"20556683211045837","article-title":"Effects of therapy with a free-standing robotic exoskeleton on motor function and other health indicators in people with severe mobility impairment due to chronic stroke: A quasi-controlled study","volume":"8","author":"Postol","year":"2021","journal-title":"J. Rehabil. Assist. Technol. Eng."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1374","DOI":"10.1007\/s42235-022-00214-z","article-title":"Design and Implementation of a Rehabilitation Upper-limb Exoskeleton Robot Controlled by Cognitive and Physical Interfaces","volume":"19","author":"Lozano","year":"2022","journal-title":"J. Bionic Eng."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"174","DOI":"10.1016\/j.cogr.2024.09.001","article-title":"Emerging trends in human upper extremity rehabilitation robot","volume":"4","author":"Hasan","year":"2024","journal-title":"Cogn. Robot."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Palazzi, E., Luzi, L., Dimo, E., Meneghetti, M., Vicario, R., Luzia, R.F., Vertechy, R., and Calanca, A. (2022). An Affordable Upper-Limb Exoskeleton Concept for Rehabilitation Applications. Technologies, 10.","DOI":"10.3390\/technologies10010022"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"49121","DOI":"10.1109\/ACCESS.2021.3068929","article-title":"Improving Motor Imagery of Gait on a Brain-Computer Interface by Means of Virtual Reality: A Case of Study","volume":"9","author":"Ferrero","year":"2021","journal-title":"IEEE Access"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"101404","DOI":"10.1016\/j.rehab.2020.03.015","article-title":"Combining brain\u2013computer interface and virtual reality for rehabilitation in neurological diseases: A narrative review","volume":"64","author":"Wen","year":"2020","journal-title":"Ann. Phys. Rehabil. Med."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Iglesia, D.H.d., Mendes, A.S., Gonz\u00e1lez, G.V., Jim\u00e9nez-Bravo, D.M., and Santana, J.F.d.P. (2020). Connected Elbow Exoskeleton System for Rehabilitation Training Based on Virtual Reality and Context-Aware. Sensors, 20.","DOI":"10.3390\/s20030858"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1007\/s10209-022-00929-0","article-title":"Research and prospects of virtual reality systems applying exoskeleton technology","volume":"23","author":"Qi","year":"2024","journal-title":"Univ. Access Inf. Soc."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1186\/s12984-024-01482-y","article-title":"Immersive virtual reality for learning exoskeleton-like virtual walking: A feasibility study","volume":"21","author":"Berg","year":"2024","journal-title":"J. NeuroEng. Rehabil."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Abbate, G., Giusti, A., Randazzo, L., and Paolillo, A. (2023). A mirror therapy system using virtual reality and an actuated exoskeleton for the recovery of hand motor impairments: A study of acceptability, usability, and embodiment. Sci. Rep., 13.","DOI":"10.1038\/s41598-023-49571-7"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Su, H., Wang, S., Huang, M., Chen, Y., Lu, A., and Yang, R. (2023, January 9\u201310). VR and Exoskeleton Assisted Lower Limb Rehabilitation based on Motor Imagery BCI. Proceedings of the 2023 IEEE International Biomedical Instrumentation and Technology Conference (IBITeC), Yogyakarta, Indonesia.","DOI":"10.1109\/IBITeC59006.2023.10390929"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Topini, A., Sansom, W., Secciani, N., Bartalucci, L., Ridolfi, A., and Allotta, B. (2022). Variable Admittance Control of a Hand Exoskeleton for Virtual Reality-Based Rehabilitation Tasks. Front. Neurorobot., 15.","DOI":"10.3389\/fnbot.2021.789743"},{"key":"ref_24","first-page":"115","article-title":"A force-feedback exoskeleton for upper-limb rehabilitation in virtual reality","volume":"6","author":"Frisoli","year":"2009","journal-title":"Appl. Bionics Biomech."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Lin, C.-J., and Sie, T.-Y. (2024). Integration of Virtual Reality-Enhanced Motor Imagery and Brain-Computer Interface for a Lower-Limb Rehabilitation Exoskeleton Robot. Actuators, 13.","DOI":"10.3390\/act13070244"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"e12010","DOI":"10.2196\/12010","article-title":"Exoskeletons with virtual reality, augmented reality, and gamification for stroke patients\u2019 rehabilitation: Systematic review","volume":"6","author":"Mubin","year":"2019","journal-title":"JMIR Rehabil. Assist. Technol."},{"key":"ref_27","first-page":"145","article-title":"Virtual reality immersive environments for motor and cognitive training of elderly people\u2014A scoping review","volume":"17","author":"Wojciechowski","year":"2021","journal-title":"Hum. Technol."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Thapa, N., Park, H.J., Yang, J.G., Son, H., Jang, M., Lee, J., Kang, S.W., Park, K.W., and Park, H. (2020). The Effect of a Virtual Reality-Based Intervention Program on Cognition in Older Adults with Mild Cognitive Impairment: A Randomized Control Trial. J. Clin. Med., 9.","DOI":"10.3390\/jcm9051283"},{"key":"ref_29","unstructured":"Ministry of Foreign Affairs of Japan (2025, March 17). General Principles Concerning Measures for the Aging Society. MOFA, Available online: https:\/\/www.mofa.go.jp\/j-info\/japan\/socsec\/aging.html."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1007\/s12062-018-9225-7","article-title":"The Growth, Ageing and Urbanisation of our World","volume":"11","author":"Leeson","year":"2018","journal-title":"Popul. Ageing"},{"key":"ref_31","first-page":"696","article-title":"The effect of tongue movement on sensorimotor cortex activity during motor imagery tasks","volume":"28","author":"Waberski","year":"2005","journal-title":"NeuroImage"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"107539","DOI":"10.1016\/j.neuropsychologia.2020.107539","article-title":"Motor neuroplasticity: A MEG-fMRI study of motor imagery and execution in healthy ageing","volume":"146","author":"Marstaller","year":"2020","journal-title":"Neuropsychologia"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1842","DOI":"10.1016\/S1388-2457(99)00141-8","article-title":"Event-related EEG\/MEG synchronization and desynchronization: Basic principles","volume":"110","author":"Pfurtscheller","year":"1999","journal-title":"Clin. Neurophysiol."},{"key":"ref_34","unstructured":"Mirai Innovation Research Institute (2025, March 17). WAVEX\u2014Mirai Innovation Research Institute. Available online: https:\/\/www.mirai-innovation-lab.com\/wavex\/."},{"key":"ref_35","unstructured":"AURA Neurotechnology (2023, August 10). AURA: Advanced EEG Neurotechnology. AURA. Available online: https:\/\/aura-neuro.tech\/."},{"key":"ref_36","unstructured":"Unity3D, LabStreamingLayer Framework (2025, March 17). GitHub Repository. Available online: https:\/\/github.com\/charlespwd\/project-title."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"100823","DOI":"10.1016\/j.measen.2023.100823","article-title":"Machine learning techniques for electroencephalogram based brain-computer interface: A systematic literature review","volume":"28","author":"Dhiman","year":"2023","journal-title":"Meas. Sensors"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"398","DOI":"10.1016\/j.bspc.2016.09.007","article-title":"Comparison of signal decomposition methods in classification of EEG signals for motor-imagery BCI system","volume":"31","author":"Kevric","year":"2016","journal-title":"Biomed. Signal Process. Control."},{"key":"ref_39","unstructured":"(2025, March 17). Discrete Wavelet Transform (DWT)\u2014PyWavelets Documentation. Available online: https:\/\/pywavelets.readthedocs.io\/en\/latest\/ref\/dwt-discrete-wavelet-transform.html."},{"key":"ref_40","unstructured":"(2025, March 17). Wavelet Families() \u2014 PyWavelets Documentation. Available online: https:\/\/pywavelets.readthedocs.io\/en\/latest\/ref\/wavelets.html."},{"key":"ref_41","unstructured":"Team, K. (2025, March 17). Keras Documentation: Keras 3 API Documentation. Available online: https:\/\/keras.io\/api\/."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"H\u00f8eg, E.R., Povlsen, T.M., Ram, J., Lange, B., Nilsson, N.C., Haugaard, K.B., Faber, S.M., Hansen, S.W., Kimby, C.K., and Serafin, S. (2021). System Immersion in Virtual Reality-Based Rehabilitation of Motor Function in Older Adults: A Systematic Review and Meta-Analysis. Front. Virtual Real., 2.","DOI":"10.3389\/frvir.2021.647993"},{"key":"ref_43","unstructured":"Alice OSE Exoskeleton\u2014INDI by Jes\u00fas TAMEZ-DUQUE (2025, March 17). INDI by Jes\u00fas TAMEZ-DUQUE. Available online: http:\/\/www.indi.global\/alice."}],"container-title":["Bioengineering"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2306-5354\/12\/4\/331\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:58:28Z","timestamp":1760029108000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2306-5354\/12\/4\/331"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,3,22]]},"references-count":43,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2025,4]]}},"alternative-id":["bioengineering12040331"],"URL":"https:\/\/doi.org\/10.3390\/bioengineering12040331","relation":{},"ISSN":["2306-5354"],"issn-type":[{"value":"2306-5354","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,3,22]]}}}