title: Exploring methodological frameworks for a mental task-based near-infrared spectroscopy brain-computer interface.
abstract: BACKGROUND
  Near-infrared spectroscopy (NIRS) brain-computer interfaces (BCIs) enable users to interact with their environment using only cognitive activities. This paper presents the results of a comparison of four methodological frameworks used to select a pair of tasks to control a binary NIRS-BCI; specifically, three novel personalized task paradigms and the state-of-the-art prescribed task framework were explored.
  
  
  METHODS
  Three types of personalized task selection approaches were compared, including: user-selected mental tasks using weighted slope scores (WS-scores), user-selected mental tasks using pair-wise accuracy rankings (PWAR), and researcher-selected mental tasks using PWAR. These paradigms, along with the state-of-the-art prescribed mental task framework, where mental tasks are selected based on the most commonly used tasks in literature, were tested by ten able-bodied participants who took part in five NIRS-BCI sessions.
  
  
  RESULTS
  The frameworks were compared in terms of their accuracy, perceived ease-of-use, computational time, user preference, and length of training. Most notably, researcher-selected personalized tasks resulted in significantly higher accuracies, while user-selected personalized tasks resulted in significantly higher perceived ease-of-use. It was also concluded that PWAR minimized the amount of data that needed to be collected; while, WS-scores maximized user satisfaction and minimized computational time.
  
  
  CONCLUSIONS
  In comparison to the state-of-the-art prescribed mental tasks, our findings show that overall, personalized tasks appear to be superior to prescribed tasks with respect to accuracy and perceived ease-of-use.
  
  
  CONCLUSIONS
  The deployment of personalized rather than prescribed mental tasks ought to be considered and further investigated in future NIRS-BCI studies.
authors.affiliation: Bloorview Research Institute, Holland Bloorview Kids Rehabilitation Hospital, 150 Kilgour Road, Toronto, ON, Canada M4G 1R8; Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College St, Toronto, ON, Canada M5S 3G9.
authors.forename: Sabine
authors.initials: S
authors.lastname: Weyand
authors.affiliation: Department of Psychology, University of Toronto, 100 St. George Street, Toronto, ON, Canada M5S 3G3.
authors.forename: Kaori
authors.initials: K
authors.lastname: Takehara-Nishiuchi
authors.affiliation: Bloorview Research Institute, Holland Bloorview Kids Rehabilitation Hospital, 150 Kilgour Road, Toronto, ON, Canada M4G 1R8; Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College St, Toronto, ON, Canada M5S 3G9. Electronic address: tom.chau@utoronto.ca.
authors.forename: Tom
authors.initials: T
authors.lastname: Chau
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000502:physiology*; D062207:Brain-Computer Interfaces; D005260:Female; D006801:Humans; D008297:Male; D008606:Mental Processes / Q000502:physiology*; D058765:Neurofeedback / Q000502:physiology; D009483:Neuropsychological Tests; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D013997:Time Factors; D055815:Young Adult
keywords: Accuracy; Brain–computer interface; Ease-of-use; Near-infrared spectroscopy; Personalized mental tasks; Prescribed mental tasks