Response of the whole-brain network.

<p><b>A:</b> Spontaneous (<i>blue</i>) and evoked (<i>red</i>) activity of the network for the excitatory populations (<i>top</i>) and the inhibitory populations (<i>bottom</i>). The yellow dots indicate the eight brain regions receiving the external input, which are: r/lLOCC, r/lMT, r/lPCAL, r/lST. <b>B:</b> Trial-by-trial variance change (Δσ²) with respect to the spontaneous condition for the excitatory populations (<i>top</i>) and the inhibitory populations (<i>bottom</i>). Yellow dots indicate the eight brain regions receiving the external input. <b>C:</b> Relation between the amount of mean synaptic change (Δm) and the amount of variance change (Δσ²) for the excitatory populations (<i>black</i>) and the inhibitory populations (<i>gray</i>). <b>D:</b> Temporal dynamics of Δm (<i>top</i>) and Δσ² (<i>bottom</i>). Each line traces the time evolution of Δm (or Δσ²) of each brain region. The shaded area indicates the application of the stimulus. <b>E:</b> The stimulus-induced relative change of the power spectral density (ΔPSD) was computed for the excitatory populations (<i>left</i>) and the inhibitory populations (<i>right</i>). <i>Blue</i>: brain regions receiving a direct external input; <i>gray</i>: brain regions receiving an indirect external input; <i>black</i>: average across brain regions. <b>F:</b> The relation between Δm and Δσ² is shown for 20 random stimulations constructed by randomly selecting eight nodes to which and external input is imposed (each color represents a given stimulation). <b>G:</b> Probability density function (p.d.f) of the relative change of the covariances between excitatory nodes. For each pair of nodes (<i>i</i>,<i>j</i>) we calculate the relative difference between the spontaneous covariance and the covariance evoked in the 20 random stimulations. <b>H:</b> Change of the correlations between excitatory nodes. For each pair of nodes (<i>i</i>,<i>j</i>) we calculate the difference between the spontaneous correlation coefficient and the correlation coefficient evoked in the 20 random stimulations.