Abstract
Recent developments in non-invasive imaging techniques have made possible the identification of various cortical areas related to gustation. Among these methods, MEG has been highly effective in the localization of the primary gustatory cortex, exhibiting both fine temporal and spatial resolution. We measured gustatory-evoked magnetic fields using a tactile free taste stimulator, and found the shortest latencies of activation to occur at the transition area between the parietal operculum and insula (area G) and at the bottom of the central sulcus (CS). We found that the latency of area G activation differed among tastants, and the frontal operculum and anterior insula were activated after long latencies after area G activation. The magnitude of activity in area G increased in a tastant concentration-dependent manner to a greater degree than did perceived intensity; the latency, however, did not correlate with concentration. The identification of these two areas as the PGA is consistent with the aforementioned clinical symptoms associated with lesions or epileptic foci in the parietal lobe.
