Fig. 7.

Default network mode. A No external stimulus is applied to the cortical neural populations (NMDA and GABA-receptor populations) and the level of dopamine is defined by $\varphi (t)={\varphi }_{\mathit{tonic}}=0.5$ for all t. B Raster plot of the spiking activity of the simulated populations of the cortical neurons when no external stimulus is injected to the cortical network and the level of dopamine is defined by ${\varphi }_{\mathit{tonic}}=0.5$. The NMDA-cortical population’s excitatory response is applied to the $D_1$-MSNs, the $D_2$-MSNs, the STN and the thalamus, and the result is given in Fig. 8. Each black dot corresponds to a spike of the corresponding neuron at a given time. The green function on the raster plot shows the average firing rate of the NMDA-cortical neurons for the 20 simulations produced. The raster plot is for one of these simulations. The sparks indicate excitatory connections, whereas the circles are inhibitory connections