title: Non-synchronous behavior of neuronal activity, oxidative metabolism and blood supply during mental tasks in man.
abstract: In near-infrared spectroscopic studies during mental tasks such as problem solving and mental arithmetic, we found that 9 of 33 healthy volunteers showed decreases in both the regional cerebral blood flow (r-CBF) and oxygen consumption rate (CMRO2) in the frontal region of the dominant hemisphere. To confirm these unexpected observations, we performed simultaneous measurements by positron emission tomography (PET) and near-infrared spectroscopy (NIRS) in two such subjects. PET images also showed that CBF decreased within the presumptive area illuminated by near-infrared light during mental task. However, CBF decreased in almost all regions while the subject gave a correct answer. Thus, the questions arose: Are mental tasks always associated with increases in r-CBF and/or CMRO2?
authors.affiliation: Institute for Electronic Science, Hokkaido University, Sapporo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hoshi
authors.forename: H
authors.initials: H
authors.lastname: Onoe
authors.forename: Y
authors.initials: Y
authors.lastname: Watanabe
authors.forename: J
authors.initials: J
authors.lastname: Andersson
authors.forename: M
authors.initials: M
authors.lastname: Bergström
authors.forename: A
authors.initials: A
authors.lastname: Lilja
authors.forename: B
authors.initials: B
authors.lastname: Långström
authors.forename: M
authors.initials: M
authors.lastname: Tamura
mesh_terms: D000328:Adult; D001923:Brain Chemistry / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008606:Mental Processes / Q000502:physiology*; D008875:Middle Aged; D009474:Neurons / Q000378:metabolism / Q000502:physiology*; D010084:Oxidation-Reduction; D010101:Oxygen Consumption / Q000502:physiology*; D010108:Oxyhemoglobins / Q000378:metabolism; D013055:Spectrophotometry, Infrared; D014055:Tomography, Emission-Computed
chemical_list: D010108:Oxyhemoglobins