title: Noninvasive imaging of prefrontal activation during attention-demanding tasks performed while walking using a wearable optical topography system.
abstract: Optical topography (OT) based on near-infrared spectroscopy is a noninvasive technique for mapping the relative concentration changes in oxygenated and deoxygenated hemoglobin (oxy- and deoxy-Hb, respectively) in the human cerebral cortex. In our previous study, we developed a small and light wearable optical topography (WOT) system that covers the entire forehead for monitoring prefrontal activation. In the present study, we examine whether the WOT system is applicable to OT measurement while walking, which has been difficult with conventional OT systems. We conduct OT measurements while subjects perform an attention-demanding (AD) task of balancing a ping-pong ball on a small card while walking. The measured time course and power spectra of the relative concentration changes in oxy- and deoxy-Hb show that the step-related changes in the oxy- and deoxy-Hb signals are negligible compared to the task-related changes. Statistical assessment of the task-related changes in the oxy-Hb signals show that the dorsolateral prefrontal cortex and rostral prefrontal area are significantly activated during the AD task. These results suggest that our functional imaging technique with the WOT system is applicable to OT measurement while walking, and will be a powerful tool for evaluating brain activation in a natural environment.
authors.affiliation: Hitachi, Ltd., Advanced Research Laboratory, Hatoyama, Saitama, Japan. hirokazu.atsumori.et@hitachi.com
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Atsumori
authors.forename: Masashi
authors.initials: M
authors.lastname: Kiguchi
authors.forename: Takusige
authors.initials: T
authors.lastname: Katura
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Funane
authors.forename: Akiko
authors.initials: A
authors.lastname: Obata
authors.forename: Hiroki
authors.initials: H
authors.lastname: Sato
authors.forename: Takaaki
authors.initials: T
authors.lastname: Manaka
authors.forename: Mitsumasa
authors.initials: M
authors.lastname: Iwamoto
authors.forename: Atsushi
authors.initials: A
authors.lastname: Maki
authors.forename: Hideaki
authors.initials: H
authors.lastname: Koizumi
authors.forename: Kisou
authors.initials: K
authors.lastname: Kubota
mesh_terms: D001288:Attention / Q000502:physiology*; D001931:Brain Mapping / Q000295:instrumentation*; D002540:Cerebral Cortex / Q000502:physiology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005071:Evoked Potentials / Q000502:physiology*; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D010100:Oxygen / Q000032:analysis; D013647:Task Performance and Analysis; D041622:Tomography, Optical / Q000295:instrumentation*; D016138:Walking / Q000502:physiology*
chemical_list: D010100:Oxygen