title: Development, set-up and first results for a one-channel near-infrared spectroscopy system.
abstract: Abstract Near-infrared spectroscopy (NIRS) is a non-invasive optical technique that can be used to assess functional activity in the human brain. This work describes the set-up of a one-channel NIRS system designed for use as an optical brain-computer interface (BCI) and reports on first measurements of deoxyhemoglobin (Hb) and oxyhemoglobin (HbO(2)) changes during mental arithmetic tasks. We found relatively stable and reproducible hemodynamic responses in a group of 13 healthy subjects. Unexpected observations of a decrease in HbO(2) and increase in Hb concentrations measured over the prefrontal cortex were in contrast to the typical hemodynamic responses (increase in HbO(2), decrease in Hb) during cortical activation previously reported.
authors.affiliation: Laboratory of Brain-Computer Interfaces, Institute for Knowledge Discovery, Graz University of Technology, Graz, Austria. g.bauernfeind@tugraz.at
authors.forename: Günther
authors.initials: G
authors.lastname: Bauernfeind
authors.forename: Robert
authors.initials: R
authors.lastname: Leeb
authors.forename: Selina Christin
authors.initials: SC
authors.lastname: Wriessnegger
authors.forename: Gert
authors.initials: G
authors.lastname: Pfurtscheller
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D006801:Humans; D008029:Lighting / Q000295:instrumentation; D008297:Male; D010108:Oxyhemoglobins / Q000032:analysis*; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation* / Q000379:methods
chemical_list: D010108:Oxyhemoglobins