Figure 8.

Time evolution of the average effective excitatory (violet) and inhibitory (green) synaptic weights ${\overline{w}}^{(exc)}$ and ${\overline{w}}^{(inh)}$, as defined by (6). The network contains 200 and 200 excitatory and inhibitory neurons. Also shown is the average balanced weight (red), given by ${\overline{w}}^{(exc)}+{\overline{w}}^{(inh)}$. Left: Using Oja’s rule (8). Right: Using the flux rule (2), as for Fig. 6, but this time with the limiting factor G(x) = x₀ + x(1 − 2y) replaced by a constant, G → 10. Both approaches fail to produce a balanced synaptic weight distribution.