title: Multiple-time replicability of near-infrared spectroscopy recording during prefrontal activation task in healthy men.
abstract: Near-infrared spectroscopy (NIRS) has the potential for clinical application in neuropsychiatry because it enables non-invasive and convenient measurement of hemodynamic response to cognitive activation. Using 24-channel NIRS in 12 healthy men, we examined the replicability of oxy- and deoxy-hemoglobin concentration ([oxyHb], [deoxyHb]) changes in the prefrontal cortex during the category fluency task over four repeated sessions (each 1-week apart). Multiple methods were employed to evaluate the replicability of magnitude, location, and time course of the NIRS signals ([oxyHb], [deoxyHb]). Task performances did not differ significantly across sessions, nor were they significantly correlated with NIRS signals. Repeated measures ANOVA and variance component analysis indicated high replicability of magnitude for both NIRS measures, whereas the effect sizes of between-session differences in [oxyHb] were not negligible. The number and spatial location of significantly activated channels were sufficiently replicable for both measures, except that the across-session overlap of significantly activated channels was weak in [deoxyHb]. The time course of the activation was acceptably replicable in both measures. Taken together, these findings suggest there is considerable replicability of multiple-time measurements of prefrontal hemodynamics during cognitive activation in men. Further studies using different conditions or assessing sensitivity to longitudinal changes following interventions are necessary.
authors.affiliation: Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan. tkono-tky@umin.ac.jp
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kono
authors.forename: Koji
authors.initials: K
authors.lastname: Matsuo
authors.forename: Koichi
authors.initials: K
authors.lastname: Tsunashima
authors.forename: Kiyoto
authors.initials: K
authors.lastname: Kasai
authors.forename: Ryu
authors.initials: R
authors.lastname: Takizawa
authors.forename: Mark A
authors.initials: MA
authors.lastname: Rogers
authors.forename: Hidenori
authors.initials: H
authors.lastname: Yamasue
authors.forename: Tetsu
authors.initials: T
authors.lastname: Yano
authors.forename: Yuji
authors.initials: Y
authors.lastname: Taketani
authors.forename: Nobumasa
authors.initials: N
authors.lastname: Kato
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D002560:Cerebrovascular Circulation; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D010108:Oxyhemoglobins / Q000378:metabolism; D017397:Prefrontal Cortex / Q000502:physiology*; D015203:Reproducibility of Results; D019265:Spectroscopy, Near-Infrared; D013997:Time Factors; D014705:Verbal Behavior / Q000502:physiology*
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins