Hemodynamic changes in response to the stimulated visual quadrants: a study with 24-channel near-infrared spectroscopy (特集脳機能計測と基礎心理学)

概要

論文の詳細を見る
Near-infrared spectroscopy (NIRS) is attracting growing interest as a powerful tool for monitoring cortical activation associated with various psychological phenomena. Many NIRS studies have aimed to explore brain functions associated with visual perception. However, how NIRS can monitor hemodynamic responses in the visual cortex corresponding to stimulation of each visual quadrant is not well known. Here we measured changes in concentration of oxygenated hemoglobin and deoxygenated hemoglobin in the human visual cortex with a 24-ch NIRS instrument. Through individual stimulation of visual quadrants we found that NIRS could differentially monitor activation of the left and right hemisphere when the lower visual field was stimulated, but hardly detected activation of both hemispheres when the upper visual field was stimulated. The result of fMRI scans using the same stimuli suggests that the different measurement responses to upper- and lower visual field stimulation are caused by the differences in the depth from the scalp of the region representing each visual field. On the basis of the present results, we discuss the limitations and potential of NIRS measurements.
2009-09-30