Figure 2.

Dynamic causal modeling was used to investigate the modulation of connections between the IFG and FFA/PPA by switch-related activity in the BG. A, The basic architecture of the model included connections from the IFG to the FFA and PPA (black) and the following inputs: novelty to the IFG, switch to the BG, attention to faces to the FFA, and attention to scenes to the PPA. B, We tested 16 alternative models that could include connections from IFG to BG (orange), from BG to IFG (blue), reciprocal connection between FFA and PPA (red), and modulation of IFG to FFA/PPA connectivity by the BG (green). Dark gray boxes indicate that this connection was included in the model. The best model (16) included all connections.