Detection of First and Second Order Motion

A model of motion detection is presented. The model contains three stages. The first stage is unoriented and is selective for contrast polarities.The next two stages work in parallel. A phase insensitive stage pools across different contrast polarities through a spatiotemporal filter and thus can detect first and second order motion. A phase sensitive stage keeps contrast polarities separate, each of which is filtered through a spatiotemporal filter, and thus only first order motion can be detected.