Follow the script: the role of vmPFC in the reinstatement and instantiation of event schemata during event construction

Previous evidence has shown that the ventromedial prefrontal cortex (vmPFC) has a role in schematic processing and event construction. Here, we tested whether vmPFC mediates the activation of event schemata (scripts; i.e. reinstatement), or their instantiation during event construction. vmPFC patients and healthy and brain-damaged controls performed (1) a script production task and (2) an event generation task in three experimental conditions: in one condition the to be imagined events did not obey a script (non-scripted condition), in one condition they obeyed a script (scripted condition), and in one condition they obeyed a script that served as an external cue for event generation (cued-scripted condition). At the script production task, vmPFC patients showed accurate knowledge of the main structure of scripts, but insufficient knowledge of their finer details, suggesting impaired script reinstatement. In line with previous studies, vmPFC patients' event construction performance was impaired in the non-scripted and scripted condition; however, it significantly improved when the script of the to be constructed events was externally cued during event generation, suggesting preserved schema instantiation. These findings indicate that vmPFC integrity is crucial for the reinstatement of scripts, but not for their instantiation when externally provided.