title: Near-infrared spectroscopy study of language activated hyper- and hypo-oxygenation in human prefrontal cortex.
abstract: Oxygenation changes in the left prefrontal cortex during language processing were assessed with near-infrared spectroscopy (NIRS). Oxyhemoglobin and deoxyhemoglobin concentrations at the Fp1 site during 5 min of resting with eyes closed (control), followed by 5 min of reading aloud, were monitored. A statistically significant change in the oxyhemoglobin concentration was observed by NIRS in all the subjects after execution of the experimental task. The observations of hyper-oxygenation as well as hypo-oxygenation in the present investigation extend past studies and suggest a complex phenomenon of activation that may be the result of a vascular steal mechanism, attenuated activation baselines, or active cortical deactivation.
authors.affiliation: Department of Physiology, Medical Sciences Building, University of Toronto, Toronto, Ontario, Canada.
authors.forename: K Ruth
authors.initials: KR
authors.lastname: Liu
authors.forename: Donald S
authors.initials: DS
authors.lastname: Borrett
authors.forename: Anita
authors.initials: A
authors.lastname: Cheng
authors.forename: Donna
authors.initials: D
authors.lastname: Gasparro
authors.forename: Hon C
authors.initials: HC
authors.lastname: Kwan
mesh_terms: D000293:Adolescent; D000328:Adult; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood*; D010108:Oxyhemoglobins / Q000378:metabolism; D017397:Prefrontal Cortex / Q000098:blood supply / Q000378:metabolism*; D011932:Reading; D019265:Spectroscopy, Near-Infrared
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; C100003:deoxyhemoglobin; D010100:Oxygen