2017 年 17 巻 2 号 p. 99-107
In this study, we aimed to clarify comfortable lighting locations (on both the wall and ceiling) for office work. To this end, we measured brain activity using fNIRS during arithmetic and copying tasks for various lighting locations in a simulated office space, and had participants provide subjective evaluations of these lighting conditions. There were four main results: (1) for the subjective evaluations, we observed no differences in impressions according to lighting condition. (2) The cerebral blood flow in the “wall” condition was significantly lower than that during the “ceiling” condition. (3) Changes in oxy-HB concentrations were found to differ according to condition even when task performance was the same. (4) For cognitively demanding tasks, the walls-only lighting condition seems to be the most comfortable environment. Conversely, for tasks requiring little concentration, the environment seemed most comfortable by having the lighting on the walls be brighter than that on the ceiling.