15. The computer-readable storage medium of claim 14 , wherein the first top-down message is further based on history of a previous state of the node in the inference stage.
15. The computer-readable storage medium of claim 14 , wherein the first top-down message is further based on history of a previous state of the node in the inference stage. 20. The computer-readable storage medium of claim 15 , further comprising computer instructions to generate a bottom-up message representing information that the second input patterns received at the node in the inference stage correspond to the learned spatial co-occurrences based on the second input patterns, the spatial co-occurrences information, and history of a state of the node.