title: Asynchronous BCI control using high-frequency SSVEP.
abstract: BACKGROUND
  Steady-State Visual Evoked Potential (SSVEP) is a visual cortical response evoked by repetitive stimuli with a light source flickering at frequencies above 4 Hz and could be classified into three ranges: low (up to 12 Hz), medium (12-30) and high frequency (> 30 Hz). SSVEP-based Brain-Computer Interfaces (BCI) are principally focused on the low and medium range of frequencies whereas there are only a few projects in the high-frequency range. However, they only evaluate the performance of different methods to extract SSVEP.
  
  
  METHODS
  This research proposed a high-frequency SSVEP-based asynchronous BCI in order to control the navigation of a mobile object on the screen through a scenario and to reach its final destination. This could help impaired people to navigate a robotic wheelchair. There were three different scenarios with different difficulty levels (easy, medium and difficult). The signal processing method is based on Fourier transform and three EEG measurement channels.
  
  
  RESULTS
  The research obtained accuracies ranging in classification from 65% to 100% with Information Transfer Rate varying from 9.4 to 45 bits/min.
  
  
  CONCLUSIONS
  Our proposed method allows all subjects participating in the study to control the mobile object and to reach a final target without prior training.
authors.affiliation: Gabinete de Tecnología Médica, Facultad de Ingeniería, Universidad Nacional de San Juan, San Juan, Argentina. pdiez@gateme.unsj.edu.ar
authors.forename: Pablo F
authors.initials: PF
authors.lastname: Diez
authors.forename: Vicente A
authors.initials: VA
authors.lastname: Mut
authors.forename: Enrique M
authors.initials: EM
authors.lastname: Avila Perona
authors.forename: Eric
authors.initials: E
authors.lastname: Laciar Leber
mesh_terms: D000328:Adult; D000465:Algorithms; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D058765:Neurofeedback / Q000295:instrumentation* / Q000379:methods*; D010775:Photic Stimulation; D012984:Software; D014584:User-Computer Interface