Neural coding of orientation information in early vision based on colinear synchronization

The perception of the global orientation of a bar originates from the population of V1 neurons which is retinotopically distributed. We carried out psychophysical experiments in order to investigate the phenomenological mechanisms of neural coding for the perception of bar orientations. We specifically examined whether perceptual segmentation affects the neural grouping. In order to further investigate cortical mechanisms for the coding, we developed a V1 network model including coupled oscillators based on colinear synchronization. Simulations of the model with various kinds of bar junctions show that the intersection of the bars is not taken into account for the determination of the global orientation of either bar, which agrees with the phenomenological mechanism observed in the psychophysical experiments