抄録
Analyses of experimental tasks for odorant stimulation and responses in higher center of olfaction, Life Electronics Laboratory, Kansai-center, AIST, Japan.
The present study is to develop the suitable odorant stimulation and to obtain the olfactory active areas using magnetoencephalography(MEG) non-invasively and to clear the first order olfactory center and the more higher olfactory center. The olfactory magnetic fields were measured by a 122-ch whole-cortex biomagnetometer with three different stimulation tasks, individually. In the first experiment the evoked response(latency: 300-400ms) were obtained using the odor stimulation synchronized with subject's respiration and active areas were estimated in the bilateral orbito-frontal areas which were coincident with regions found as the higher olfactory center in monkey. In our second experiment, we applied an odd-ball paradigm using two odors by the different present rates and obtained the more later component such as cognitive response in a few superior temporal or near the insular areas. In the third experiment, we tried to study active olfaction by self sniffing odor. Right hemisphere dominance was found in the orbito-frontal area and the attentive olfactory activity might be emphasized preliminary. These three experimental tasks and results suggest us the idea of mechanism on the higher order olfactory information processing in human. [Jpn J Physiol 54 Suppl:S19 (2004)]
