Machine learning modelling for multi-order human visual motion processing

Visual motion perception is a key function for agents interacting with their environment. Although recent advances in optical flow estimation using deep neural networks have surpassed human-level accuracy, a notable disparity remains. In addition to limitations in luminance-based first-order motion perception, humans can perceive motions in higher-order features—an ability lacking in conventional optical flow models that rely on intensity conservation law. To address this, we propose a dual-pathway model that mimics the cortical V1-MT motion processing pathway. It uses a trainable motion energy sensor bank and a recurrent graph network to process luminance-based motion and incorporates an additional sensing pathway with nonlinear preprocessing using a multilayer 3D CNN block to capture higher-order motion signals. We hypothesize that higher-order mechanisms are critical for estimating robust object motion in natural environments that contain complex optical fluctuations, for example, highlights on glossy surfaces. By training on motion datasets with varying material properties of moving objects, our dual-pathway model naturally developed the capacity to perceive multi-order motion as humans do. The resulting model effectively aligns with biological systems while generalizing both luminance-based and higher-order motion phenomena in natural scenes.