Excitation inhibition balance.

The asymptotic value of the homogeneous inhibitory synaptic weight is shown as a function of the asymptotic mean excitatory synaptic weights, . Learning dynamics of a population of inhibitory and excitatory feed forward synapses onto a single integrate and fire post synaptic cell were simulated (see Methods). The firing rate statistics of the presynaptic neurons followed a Poisson process with uniform rates of 10 spikes/s. The firing of different inhibitory neurons were taken to be independent, whereas the excitatory neurons were modeled to have uniform correlations. To obtain different values for the mean excitatory input to the cell we varied the level of the uniform correlations between all presynaptic excitatory neurons , from bottom to top. Here we used the following parameters , , and . The dashed line shows a linear regression line, for comparison.