{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T21:39:59Z","timestamp":1780695599324,"version":"3.54.1"},"reference-count":32,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,8,14]],"date-time":"2025-08-14T00:00:00Z","timestamp":1755129600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurorobot."],"abstract":"<jats:p>Brain-computer interface (BCI) integration with virtual reality (VR) has progressed from single-limb control to multi-limb coordination, yet achieving intuitive tri-manual operation remains challenging. This study presents a consumer-grade hybrid BCI-VR framework enabling simultaneous control of two biological hands and a virtual third limb through integration of Tobii eye-tracking, NeuroSky single-channel EEG, and non-haptic controllers. The system employs e-Sense attention thresholds (&amp;gt;80% for 300\u202fms) to trigger virtual hand activation combined with gaze-driven targeting within 45\u00b0 visual cones. A soft maximum weighted arbitration algorithm resolves spatiotemporal conflicts between manual and virtual inputs with 92.4% success rate. Experimental validation with eight participants across 160 trials demonstrated 87.5% virtual hand success rate and 41% spatial error reduction (<jats:italic>\u03c3<\/jats:italic>\u202f=\u202f0.23\u202fmm vs. 0.39\u202fmm) compared to traditional dual-hand control. The framework achieved 320\u202fms activation latency and 22% NASA-TLX workload reduction through adaptive cognitive load management. Time-frequency analysis revealed characteristic beta-band (15-20\u202fHz) energy modulations during successful virtual limb control, providing neurophysiological evidence for attention-mediated supernumerary limb embodiment. These findings demonstrate that sophisticated algorithmic approaches can compensate for consumer-grade hardware limitations, enabling laboratory-grade precision in accessible tri-manual VR applications for rehabilitation, training, and assistive technologies.<\/jats:p>","DOI":"10.3389\/fnbot.2025.1628968","type":"journal-article","created":{"date-parts":[[2025,8,14]],"date-time":"2025-08-14T05:35:24Z","timestamp":1755149724000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":6,"title":["Tri-manual interaction in hybrid BCI-VR systems: integrating gaze, EEG control for enhanced 3D object manipulation"],"prefix":"10.3389","volume":"19","author":[{"given":"Jian","family":"Teng","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sukyoung","family":"Cho","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaw-mung","family":"Lee","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,8,14]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"21558","DOI":"10.1038\/s41598-024-72358-3","article-title":"Neural signatures of motor imagery for a supernumerary thumb in VR: an EEG analysis","volume":"14","author":"Alsuradi","year":"2024","journal-title":"Sci. Rep."},{"key":"ref2","doi-asserted-by":"publisher","first-page":"9769","DOI":"10.1038\/s41598-022-13981-w","article-title":"Embodiment of supernumerary robotic limbs in virtual reality","volume":"12","author":"Arai","year":"2022","journal-title":"Sci. Rep."},{"key":"ref3","doi-asserted-by":"publisher","first-page":"3171","DOI":"10.3390\/electronics11193171","article-title":"Hybrid asynchronous brain-computer interface combining SSVEP and eye-tracking for dynamic threatening pedestrian identification in driving","volume":"11","author":"Chen","year":"2022","journal-title":"Electronics"},{"key":"ref4","first-page":"3341","article-title":"Hybrid asynchronous brain-computer interface combining SSVEP and eye-tracking for dynamic threatening pedestrian identification in driving","volume-title":"IEEE","author":"Chin","year":"2010"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"947","DOI":"10.1016\/j.procs.2019.04.132","article-title":"A novel helmet design and implementation for drowsiness and fall detection of workers on-site using EEG and Random-Forest Classifier","volume":"151","author":"Dhole","year":"2019","journal-title":"Proc. Comput. Sci."},{"key":"ref6","doi-asserted-by":"publisher","first-page":"1146415","DOI":"10.3389\/fnbot.2023.1146415","article-title":"A robotic arm control system with simultaneous and sequential modes combining eye-tracking with steady-state visual evoked potential in virtual reality environment","volume":"17","author":"Guo","year":"2023","journal-title":"Front. Neurorobot."},{"key":"ref7","first-page":"904","article-title":"NASA-task load index (NASA-TLX); 20 years later","author":"Hart","year":"2006"},{"key":"ref8","first-page":"139","article-title":"Development of NASA-TLX (Task Load Index): Results of empirical and theoretical research","volume-title":"Advances in psychology","author":"Hart","year":"1988"},{"key":"ref9","doi-asserted-by":"publisher","first-page":"484","DOI":"10.1080\/10447318.2020.1826190","article-title":"Comparison of eye-based and controller-based selection in virtual reality","volume":"37","author":"Hou","year":"2021","journal-title":"Int. J. Human Comput. Interact."},{"key":"ref9001","doi-asserted-by":"crossref","first-page":"65745","DOI":"10.1109\/ACCESS.2019.2917918","article-title":"Resting state EEG-based biometric system using concatenation of quadrantal functional networks","volume":"7","author":"Kim","year":"2019","journal-title":"Ieee Access."},{"key":"ref10","doi-asserted-by":"crossref","DOI":"10.1109\/COINS61597.2024.10622556","article-title":"Acceleration of eeg signal processing on fpga: a step towards embedded bci","author":"Kundu","year":"2024"},{"key":"ref11","doi-asserted-by":"publisher","first-page":"1347974","DOI":"10.3389\/fnhum.2024.1347974","article-title":"A method for synchronized use of EEG and eye tracking in fully immersive VR","volume":"18","author":"Larsen","year":"2024","journal-title":"Front. Hum. Neurosci."},{"key":"ref12","doi-asserted-by":"publisher","first-page":"29","DOI":"10.1145\/3670653.3670657","article-title":"Multimodal detection of external and internal attention in virtual reality using EEG and eye tracking features","volume":"2024","author":"Long","year":"2024","journal-title":"Proc. Mensch Comput."},{"key":"ref13","doi-asserted-by":"publisher","first-page":"031005","DOI":"10.1088\/1741-2552\/aab2f2","article-title":"A review of classification algorithms for EEG-based brain-computer interfaces: a 10 year update","volume":"15","author":"Lotte","year":"2018","journal-title":"J. Neural Eng."},{"key":"ref14","first-page":"249","article-title":"A serious game application using EEG-based brain computer interface","volume-title":"In Special Session on Brain-computer Interfaces and Brain Stimulation for Neurorehabilitation.","author":"Perales","year":"2013"},{"key":"ref15","doi-asserted-by":"publisher","first-page":"1134389","DOI":"10.3389\/fpsyg.2023.1134389","article-title":"Exercise and cognitive training interventions for older adults: from isolated behaviors to complex multimodal programs","volume":"14","author":"Perrot","year":"2023","journal-title":"Front. Psychol."},{"key":"ref16","doi-asserted-by":"publisher","first-page":"88","DOI":"10.1016\/j.cag.2022.05.024","article-title":"Understanding multi-modal brain network data: An immersive 3D visualization approach","volume":"106","author":"Pester","year":"2022","journal-title":"Comput. Graph."},{"key":"ref17","doi-asserted-by":"publisher","first-page":"9855","DOI":"10.3390\/app14219855","article-title":"Connecting the brain with augmented reality: a systematic review of BCI-AR systems","volume":"14","author":"Prapas","year":"2024","journal-title":"Appl. Sci."},{"key":"ref18","doi-asserted-by":"publisher","first-page":"377","DOI":"10.1504\/EG.2017.087994","article-title":"Behaviour state analysis through brain computer interface using wearable EEG devices: a review","volume":"13","author":"Ramakuri","year":"2017","journal-title":"Electron. Gov. Int. J."},{"key":"ref19","first-page":"1","article-title":"Towards an eye-brain-computer interface: combining gaze with the stimulus-preceding negativity for target selections in XR","author":"Reddy","year":"2024"},{"key":"ref20","doi-asserted-by":"publisher","first-page":"1134","DOI":"10.3390\/bios12121134","article-title":"A systematic review of virtual reality and robot therapy as recent rehabilitation technologies using EEG-brain-computer interface based on movement-related cortical potentials","volume":"12","author":"Said","year":"2022","journal-title":"Biosensors"},{"key":"ref21","doi-asserted-by":"publisher","first-page":"51","DOI":"10.1016\/j.cad.2014.01.006","article-title":"Human factors study on the usage of BCI headset for 3D CAD modeling","volume":"54","author":"Shankar","year":"2014","journal-title":"Comput. Aided Des."},{"key":"ref22","doi-asserted-by":"publisher","first-page":"59","DOI":"10.1016\/j.cag.2018.05.024","article-title":"Embodied VR environment facilitates motor imagery brain\u2013computer interface training","volume":"75","author":"\u0160kola","year":"2018","journal-title":"Comput. Graph."},{"key":"ref23","doi-asserted-by":"publisher","first-page":"109428","DOI":"10.1016\/j.jneumeth.2021.109428","article-title":"An autonomous hybrid brain-computer interface system combined with eye-tracking in virtual environment","volume":"366","author":"Tan","year":"2022","journal-title":"J. Neurosci. Methods"},{"key":"ref24","doi-asserted-by":"publisher","first-page":"3331","DOI":"10.3390\/s22093331","article-title":"Past, present, and future of EEG-based BCI applications","volume":"22","author":"V\u00e4rbu","year":"2022","journal-title":"Sensors"},{"key":"ref25","article-title":"Creating by imagining: use of natural and intuitive BCI in 3D CAD modeling","author":"Verma","year":"2013"},{"key":"ref26","doi-asserted-by":"publisher","first-page":"69","DOI":"10.1186\/s12984-016-0173-2","article-title":"Motor priming in virtual reality can augment motor-imagery training efficacy in restorative brain-computer interaction: a within-subject analysis","volume":"13","author":"Vourvopoulos","year":"2016","journal-title":"J. Neuro Engineering Rehabil."},{"key":"ref27","first-page":"90","article-title":"Combination of augmented reality based brain-computer interface and eye tracking for control of a multi-robot system","author":"Xu","year":"2024"},{"key":"ref28","doi-asserted-by":"crossref","DOI":"10.1007\/978-1-84996-272-8_11","article-title":"Enhancing human-computer interaction with input from active and passive brain-computer interfaces","volume-title":"Brain-Computer Interfaces","author":"Zander","year":"2010"},{"key":"ref29","doi-asserted-by":"publisher","first-page":"1426055","DOI":"10.3389\/fnhum.2024.1426055","article-title":"ChatGPT and BCI-VR: a new integrated diagnostic and therapeutic perspective for the accurate diagnosis and personalized treatment of mild cognitive impairment","volume":"18","author":"Zhang","year":"2024","journal-title":"Front. Hum. Neurosci."},{"key":"ref30","doi-asserted-by":"publisher","first-page":"5725","DOI":"10.3390\/s24175725","article-title":"Brain neuroplasticity leveraging virtual reality and brain-computer interface technologies","volume":"24","author":"Zheng","year":"2024","journal-title":"Sensors"},{"key":"ref31","doi-asserted-by":"publisher","first-page":"15","DOI":"10.1186\/s40779-024-00558-6","article-title":"Recent applications of EEG-based brain-computer-interface in the medical field","volume":"11","author":"Zhou","year":"2024","journal-title":"Mil. Med. Res."}],"container-title":["Frontiers in Neurorobotics"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fnbot.2025.1628968\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,14]],"date-time":"2025-08-14T05:35:25Z","timestamp":1755149725000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fnbot.2025.1628968\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,8,14]]},"references-count":32,"alternative-id":["10.3389\/fnbot.2025.1628968"],"URL":"https:\/\/doi.org\/10.3389\/fnbot.2025.1628968","relation":{},"ISSN":["1662-5218"],"issn-type":[{"value":"1662-5218","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,8,14]]},"article-number":"1628968"}}