Integration of heterogeneous inputs. GP inputs are labeled red or blue for neurons increasing or decreasing their firing rate, respectively. (A) Raster plot of the activity of 10 simulated GP neurons that changed their firing rate for 200 ms. Half of the neurons increased their firing rate and half of the neurons decreased their firing rate. The four examples differ in terms of their baseline firing rate: 10 (i), 20 (ii), 40 (iii) and 60 Hz (iiii). (B) Predicted membrane potential of an EP neuron that receives input from 10 GP neurons in (A). Dashed red line indicates two SD below the mean membrane potential. (C) Predicted change in membrane potential as a function of the multiplication factor and the baseline firing rate. (D) Duration of the inhibitory phase (i) and excitatory phase (ii) induced by the change in presynaptic activity. The duration of inhibition was defined as the time during which the postsynaptic membrane potential was significantly hyperpolarized (more negative than 2 SD below the mean membrane potential).