Self-organizing maps with refractory period

Self-organizing map (SOM) has been studied as a model of map formation in the brain cortex. Neurons in the cortex present a refractory period in which they are not able to be activated, restriction that should be included in the SOM if a better description is to be achieved. Altough several works have been presented in order to include this biological restriction to the SOM, they do not reflect biological plausibility. Here, we present a modification in the SOM that allows neurons to enter a refractory period (SOM-RP) if they are the best matching unit (BMU) or if they belong to its neighborhood. This refractory period is the same for all affected neurons, which contrasts with previous models. By including this biological restriction, SOM dynamics resembles in more detail behavior shown by the cortex, such as non-radial activity patterns and long distance influence, besides the refractory period. As a side effect, two error measures are lower in maps formed by SOM-RP than in those formed by SOM.