A strategy to combat uncertainty about neuronal activity is to materialize information by relative values instead of absolute ones. For instance, this is the way that sparse associative memories based on neural cliques [11] are recovered through the Winner-Takes-All (WTA) mechanism which has shown high biological plausibility [12] . Furthermore, the WTA principle is applied in several studies [13, 14,<cite> 15]</cite> for increase activation sparseness in neural networks.