Functional Roles of Receptive Field Structures in the Perception of Orientation

To investigate the cortical mechanisms underlying the determination of apparent tilt, including the tilt illusion, we developed and examined a V1 network model consisting of cortical neurons and phase-coupled oscillators for neural grouping. Grouping local orientations based on V1 colinear connections, the model showed quantitative agreement with psychophysically measured apparent tilt. Computational investigations on the functional roles of various receptive field structures suggest that even-phase receptive fields are crucial but not exclusive for the apparent orientation of a bar. Our results further suggest importance of the feedback of grouping information from complex cells, which are synchronized through colinear connections, to simple cells with specific phases