Motion Perception Neurodynamics Of Biological Vision Systems

Visual motion perception requires the solution of the two complementary problems of motion integration and of motion segmentation. A neural model is described how motion integration and segmentation processes, both within and across apertures, compute global motion percepts. The improvement and computer simulation of the model is given as well.The model proposes a solution to the global aperture problem by showing how feature tracking signals can propagate to ambiguous motion signals and capture the motion signals there. This integration process determines the global percept. It is the result of several processing stages: Directional transient cells respond to image transients and input to a directional short-range filter that selectively boosts feature tracking signals with the help of competitive signals. Then a long-range filter inputs to directional cells that pools signals over multiple orientations, opposite contrast polarities , and depth. This all happens no later than cortical area MT. The directional cells activate a directional grouping network, proposed to occur within cortical area MST. The interaction between the model MT and MST cells solves the aperture problem, accomplishes directional motion capture within that region. Model simulations include the barberpole illusion, motion capture, the spotted barberpole, the occluded translating square illusion. Qualitative explanation of those illusions are also given. Finally, we apply the model to processing the natural scene images.