1. An artificial vision system training method, including the steps: forming a feature matrix including feature sample vectors and a corresponding response sample vector including response sample scalars; determining a linkage vector linking said feature matrix to said response sample vector, characterized by an iterative linkage vector determining method including the steps: determining a response sample vector error estimate in the response sample vector domain; transforming said response sample vector error estimate into a corresponding linkage vector error estimate in the linkage vector domain; determining a linkage vector estimate in the linkage vector domain by using said linkage vector error estimate; transforming said linkage vector estimate into a corresponding response sample vector estimate in the response sample vector domain; repeating the previous steps until the response sample vector error estimate is sufficiently small.