Abstract
To investigate the functional organization essential for object vision the technique of optical imaging has been applied to the anterior part of the inferotemporal cortex, which represents the final stage of the visual cortical pathway critical for object vision. We first conducted unit recordings with electrodes and determined the features critical for the activation of single cells. In the subsequent optical imaging, presentation of the critical features activated patchy regions around 0.5mm in diameter covering the site of the electrode penetration at which the critical feature had been determined. In some cases in which more than one critical feature had been determined from a single penetration, the critical features activated partially overlapping regions extending in different directions from the penetration site. Especially, the spot activated by presentation of a face systematically moved in one direction as the face rotated in depth around its vertical axis. Thus, clustering of cells responding to the same stimulus is concluded, and overlapping of clusters representing different but related features is suggested.
