Roberto Moreno-Díaz

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Knowledge–based systems are here introduced according recent conceptions by separating knowledge representation methods from the methods for knowledge use. In each case, three fundamental levels (the user level, the knowledge engineering level and the tool development level) are distinguished. Neural Nets are classified according their function as models(More)
Our theoretical account for visual computation in a frog's retina is based on the concepts that: (a) outer retinal layers provide three spatial channels of information pertaining to local spatio-temporal properties of retinal stimuli; (b) prominent specialisation in a frog's retina is the result of a non-linear lateral interaction at the inner plexiform(More)
This paper presents a model of the spatiotemporal processes of simple ganglion cells of cat's retina. The model is based on the existence of two anatomical paths in the retina: a direct path, responsible for central excitatory effects, and a transversal path, responsible for peripherical inhibitory effects. Plausible spatial weighting functions and temporal(More)
To implement retinal models of some complexity a set of computer programs, coordinated by a main program is required. A set of said programs is presented here which permits the design and the experimentation with linear and non-linear retinal layered models. A main program, called RETINA, is the basis for the building of a model, the generation of the input(More)
The model is based on the concept that non-linear lateral interaction at the inner plexiform layer accounts for most of the specialization and marked non-linearities in cat's retinal ganglion cell responses. The inputs to the lateral interaction processes are a spatio-temporal signal and its retarded, as suggested by the behaviour of simple ganglion cells.(More)
Visual processing in avian retina is interpreted by means of a layered model in which: a) outer layers provide with spatio temporal fast and retarded versions of the stimuli incident on the retina; a possibility is that horizontal cells are involved in isotropically generating the retarded version which is transversally translated; b) prominent(More)
A theoretical general model of layered computation in the retina is presented. Each layer is functional in the sense that it may correspond or not to an anatomical layer. It is formed by computing elements which can perform in principle any non-linear arbitrary function on a three-dimensional input space. This space consists of 2 spatial dimensions, plus(More)