立体的visual flowに対するマカクザルMST野細胞の反応

抄録

Three-dimensional visual flow caused by self-movements provides important cues for the perception of space, and thus for the perception and control of own movement. At least 3 depth-cues built up by moving elements are contained in such a flow. One is purely dynamic signal independent of a visual pattern of a facing scene, i.e., ‘speed-gradient.’ The other two are rather static signal called ‘perspective,’ i.e., ‘size-gradient’ and ‘density-gradient’ in a texture pattern. We investigated relative contribution of the three cues for the perceptual impression of 3-dimensional space by presenting computer-generated virtual flow stimuli in which the three cues are controlled independently. As expected, the contribution of speed-gradient was most strong, a medium was texture size-gradient, and the weakest was texture density-gradient. We also investigated response-properties of cells in macaque MST-area using similar stimuli. MST cells are classified into three groups according to the different response-behaviors to 2-dimensional and 3-dimensional visual flow. Based on these results, a psychology-physiology correspondence is suggested.