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T Kohonen

Publications and source records attributed to T Kohonen.

7 recordsLinked to original sources

Cortical maps.

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Animals

Self-organized formation of colour maps in a model cortex.

A report is presented of computer simulations which demonstrate the applicability of self-organization principles to the formation of a cortical colour map. A two-dimensional array of cortical units can be shown to become selectively sensitive to different colour stimuli in an orderly fashion. The precortical part of the simulation model contains three wavelength-sensitive receptors with overlapping sensitivity distributions, and a simple opponent processing stage. Each cortical unit receives the same activity from the precortical stage by adaptive connections. Initially the connections are arbitrary; during self-organization they are changed so that different way. Self-organization of the connections can be shown to take place even when the stimulation of the receptors is totally random, ie the wavelength and purity (and in some simulations the distribution) of each stimulus are selected randomly.

Color Perception

Associative memory and pattern recognition.

This tutorial review presents a model of neural associative memory along with a set of computer demonstrations showing the relevance of this memory mechanism in visual information processing. The model is based upon the hypothesis that adaptive changes in neural networks are intermediated by changes in synaptic efficacies. The signal patterns are stored by gradual changes of the network and they may be recalled later using a part of the original signal pattern as a key. The ability of this type of memory mechanism to process sensory information is emphasized.

Adaptation, Physiological