ヒトの無侵襲計測―大脳皮質嗅覚野

Non-invasive measurements of human brain: olfactory active areas in the cerebral cortex

ニオイに対するヒトの脳内の嗅覚情報処理や大脳皮質嗅覚野については，これまで十分な解明が行われていなかったが，近年，生体計測技術や無侵襲的計測手法の急速な発達に伴い，ヒトの嗅覚の無侵襲計測が行えるようになってきた。本報では，まずアカゲザルの大脳皮質嗅覚野に関する概要，現在の知見について述べ，次にfMRI，PET，ならびに脳波（EEG），脳磁図（MEG）などの無侵襲計測法を用いたヒトの嗅覚計測研究の現状を紹介する。また，筆者らが行っている嗅覚脳磁図計測によって得たヒトの嗅覚中枢部位の特定，ニオイの認知に関する研究結果について述べる。

The mechanism of human olfaction and the olfactory information processing in the brain are not clear and its olfactory central area in the human brain is debatable now. However, non-invasive measurements have been recently applied to study the human olfaction. In the present paper the outline of olfactory nervous center was firstly shown by the monkey brain. Next, the current status on the human olfaction was introduced by using the non-invasive measurements such as fMRI, PET, EEG and MEG. Especially, MEG measurements of human olfaction were precisely reported. We have been shown the results of our studies on the estimation of human olfactory nervous center in the brain, and also the sensation and recognition function to odorants.