Fig. 6

This figure represents the synapse strength modification when the post-synaptic neuron emits a spike. The y-axis corresponds to an additive or multiplicative update of the connectivity. For instance, in [28], this is $\frac{\mathrm{\Delta }{\mathbf{W}}_{ij}}{{\mathbf{W}}_{ij}}$ for the negative part of the curve. However, we assume an additive update in this paper. The x-axis is the time at which a pre-synaptic spike reaches the synapse, relatively to the time of post-synaptic time chosen to be 0.