The triple-network model is a contemporary theoretical framework derived from empirical neuroimaging data to explain a wide range of observations stemming from multiple psychopathologies. Central to the model are interactions between the salience, default-mode, and central executive networks. The insula area is a central node of the salience network. Using acute photostimulation, we report evidence to support the existence of a triple-network system within the mouse brain. Further, by using sustained optogenetic neuromodulation, we show that inhibition of the insular area acts on homotopic functional connectivity but fails to affect wider interactions within triple-network system in a resting-state setting.