title: Enhancing performance of a motor imagery based brain-computer interface by incorporating electrical stimulation-induced SSSEP.
abstract: We proposed a novel simultaneous hybrid brain-computer interface (BCI) by incorporating electrical stimulation into a motor imagery (MI) based BCI system. The goal of this study was to enhance the overall performance of an MI-based BCI. In addition, the brain oscillatory pattern in the hybrid task was also investigated.
  
  
  
  64-channel electroencephalographic (EEG) data were recorded during MI, selective attention (SA) and hybrid tasks in fourteen healthy subjects. In the hybrid task, subjects performed MI with electrical stimulation which was applied to bilateral median nerve on wrists simultaneously.
  
  
  
  The hybrid task clearly presented additional steady-state somatosensory evoked potential (SSSEP) induced by electrical stimulation with MI-induced event-related desynchronization (ERD). By combining ERD and SSSEP features, the performance in the hybrid task was significantly better than in both MI and SA tasks, achieving a ~14% improvement in total relative to the MI task alone and reaching ~89% in mean classification accuracy. On the contrary, there was no significant enhancement obtained in performance while separate ERD feature was utilized in the hybrid task. In terms of the hybrid task, the performance using combined feature was significantly better than using separate ERD or SSSEP feature.
  
  
  
  The results in this work validate the feasibility of our proposed approach to form a novel MI-SSSEP hybrid BCI outperforming a conventional MI-based BCI through combing MI with electrical stimulation.
authors.affiliation: Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, People's Republic of China. Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin, People's Republic of China.
authors.forename: Weibo
authors.initials: W
authors.lastname: Yi
authors.forename: Shuang
authors.initials: S
authors.lastname: Qiu
authors.forename: Kun
authors.initials: K
authors.lastname: Wang
authors.forename: Hongzhi
authors.initials: H
authors.lastname: Qi
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.forename: Feng
authors.initials: F
authors.lastname: He
authors.forename: Peng
authors.initials: P
authors.lastname: Zhou
authors.forename: Jiajia
authors.initials: J
authors.lastname: Yang
authors.forename: Dong
authors.initials: D
authors.lastname: Ming
mesh_terms: D000328:Adult; D062207:Brain-Computer Interfaces; D004558:Electric Stimulation / Q000379:methods*; D004569:Electroencephalography / Q000379:methods*; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007092:Imagination / Q000502:physiology*; D008297:Male; D009068:Movement / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult