Bistable, Irregular Firing and Population Oscillations in a Modular Attractor Memory Network
Figure 5
Balance of currents in a single cell during three different models of activity of the network.
From 0–0.5 s network is in its ground state, from 0.5–1.5 s it is in an active state. Between 0.5–1 s the cell is part of the foreground and between 1–1.5 s it is part of the background. A: Plot of the soma potential. Note that the soma was injected with a negative current (−0.2 nA), so that the cell did not spike while we measured the balance of currents. B: Net, i.e. total excitatory+inhibitory, currents into soma. C: Top line is the excitatory current into soma, and the bottom is the inhibitory current that almost perfectly balances the excitatory one. The middle line is the net synaptic current of panel B, the result of imbalance between excitatory and inhibitory currents. Notice its significantly smaller amplitude. D: Plot of firing frequency as a function of current injected into the soma in three different cells in ground state. The dashed line corresponds to the mean firing rate in the active state in the same network.