大脳皮質におけるヘモグロビン濃度と脳波複雑性変化の相互関係について  [in Japanese] A Study on the Relationship between Hemodynamics and EEG Dynamics of Cerebral Cortex  [in Japanese]

ヒトの大脳皮質と呼ばれる部分は,記憶や学習,さらには感情や心といった高度な精神活動を司っている.脳活動を調べる技術として,近赤外光トポグラフィ(NIRS),脳波計測(EEG)などがある.前者は酸素化・脱酸素化ヘモグロビン濃度変化を測定し,後者は頭皮上の2点問の電位差で記録する.本研究では,これらの相互関係について調査した.本報告では前頭葉近傍に着目し,「感性の分離」をタスク内容として与え,同時計測をした.4人の被験者に対して解析した結果,NIRSによる感性分離出力とEEGによる感性分離出力に同様の傾向が見られ,それらの類似度は,4人のうち2人は58.5[%],65.6[%]と算出された.また,NIRS信号とEEGのタイムラグが検出され,約2.4[sec]であると示唆された.

Cerebral cortex controls high-level mental activity such as not only memory, and learning but also emotion and mind. To examine brain activation, there are technologies such as Near Infrared Spectroscopy (NIRS), Electroencephalogram (EEG) and so on. NIRS measures the concentration change of oxy- and de-oxy-hemoglobin, while EEG measures the voltage difference between two points on the scalp. In this research, correlation between these two instruments was investigated. In this report, attention was focused on the part near the frontal lobe. We gave the "detachment of Kansei" as the task content, to the subjects, and simultaneously measured. The results of analysis of four subjects showed that the output of the detachment of Kansei with using NIRS and that with using EEG had similar tendencies, and calculated similarities between NIRS and EEG of two in four subjects were 58.5% and 65.6%. Furthermore, the time lag between NIRS signal and EEG was estimated approximately 2.4[sec].