The cortical dynamics of context-dependent language processing

A previous functional magnetic resonance imaging study (Dietrich et al. [2019]. Discourse management during speech perception: A functional magnetic resonance imaging (fMRI) study. NeuroImage, 202, 116047. ) showed a contribution by the pre-supplementary motor area (pre-SMA), the inferior frontal gyrus (IFG), and the basal ganglia (BG) in the processing of discourse structure. By applying dynamic causal modelling (DCM) to the data of this previous study, we aimed to shed further light on the functional interrelationships of these areas. Discourse coherence had been manipulated by using presupposition triggers in a test sentence that either corresponded or failed to correspond to a contextual item. We found connections from pre-SMA to IFG and from pre-SMA to BG. Additionally, participants' ability to accommodate violations modulated the coupling from the BG to the pre-SMA. We discuss this pattern in light of the aslant tract transmitting control signals from the pre-SMA to the IFG that slow down procedural processing in case of errors. The pre-SMA itself seems to be regulated by the BG depending on whether participants accommodate a violation.