Dependence of the network activity on overall external input, as obtained from the mean field approximation (black solid curves) and from the network simulations (symbols), for <i>w</i>₊ = 1.62 (A) and <i>w</i>₊ = 1.75 (B).

<p>Thin solid curve: firing rates of both populations in a stable symmetric state (both populations at equal rates); thick solid curves: _ring rates of the two selective populations in an asymmetric state (one population at high rate, the other at low rate). Thick dashed lines show the position of the unstable fixed point. Dotted vertical lines indicate the boundaries of the three different regimes present in the system, as predicted by the mean field approximation. At <i>λ̅</i> = <i>λ̅</i><i>_c</i> the spontaneous state loses its stability. Error bars indicate the sample standard deviation of the firing rates.