title: Evaluation of a Compact Hybrid Brain-Computer Interface System.
abstract: We realized a compact hybrid brain-computer interface (BCI) system by integrating a portable near-infrared spectroscopy (NIRS) device with an economical electroencephalography (EEG) system. The NIRS array was located on the subjects' forehead, covering the prefrontal area. The EEG electrodes were distributed over the frontal, motor/temporal, and parietal areas. The experimental paradigm involved a Stroop word-picture matching test in combination with mental arithmetic (MA) and baseline (BL) tasks, in which the subjects were asked to perform either MA or BL in response to congruent or incongruent conditions, respectively. We compared the classification accuracies of each of the modalities (NIRS or EEG) with that of the hybrid system. We showed that the hybrid system outperforms the unimodal EEG and NIRS systems by 6.2% and 2.5%, respectively. Since the proposed hybrid system is based on portable platforms, it is not confined to a laboratory environment and has the potential to be used in real-life situations, such as in neurorehabilitation.
authors.affiliation: Machine Learning Group, Berlin Institute of Technology, Berlin, Germany.
authors.forename: Jaeyoung
authors.identifier: 0000-0003-2899-6893
authors.initials: J
authors.lastname: Shin
authors.affiliation: Machine Learning Group, Berlin Institute of Technology, Berlin, Germany; Department of Brain and Cognitive Engineering, Korea University, Seoul, Republic of Korea.
authors.forename: Klaus-Robert
authors.initials: KR
authors.lastname: Müller
authors.affiliation: NIRx Medizintechnik GmbH, Berlin, Germany.
authors.forename: Christoph H
authors.initials: CH
authors.lastname: Schmitz
authors.affiliation: Machine Learning Group, Berlin Institute of Technology, Berlin, Germany; Department of Biomedical Engineering, Chonnam National University, Yeosu, Republic of Korea.
authors.forename: Do-Won
authors.identifier: 0000-0002-4397-0774
authors.initials: DW
authors.lastname: Kim
authors.affiliation: Department of Medical IT Convergence Engineering, Kumoh National Institute of Technology, Gumi, Republic of Korea.
authors.forename: Han-Jeong
authors.identifier: 0000-0002-1183-1219
authors.initials: HJ
authors.lastname: Hwang
mesh_terms: D000328:Adult; D062207:Brain-Computer Interfaces; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008433:Mathematics; D017397:Prefrontal Cortex / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D012815:Signal Processing, Computer-Assisted; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation