Sequential causal estimation and learning from time-varying images

Dynamic models are used in modeling the perceptual systems with hierarchies. But most of the models assume Gaussian statistics on the underlying causes. In this paper we try to develop a basic building block for these hierarchical models where the causes are assumed to be non-Gaussian. We describe a sequential dual estimation framework for inferring the hidden states and unknown causes/inputs while learning the parameters of the model. It is observed that the algorithm is able to extract bases from the time varying image sequence that resembles receptive fields of the simple cells in V1. In addition, the dynamical model gives us the ability to deconvolve spatial and temporal changes in the image sequence.