Cognitive control states and traits modulate lexical competition during word production.

Word production often involves resolving competition between multiple activated word candidates. This study investigated how cognitive control states and traits modulate lexical competition during production, combining behavioral and fMRI techniques. Cognitive control states were manipulated using a Stroop-embedded picture naming task, while lexical competition was manipulated via name agreement of pictures to be named. Cognitive control traits were measured using the AX version of the Continuous Performance, Flanker, and Simon tasks. Behaviorally, higher lexical competition was associated with worse naming responses, while Stroop conflict trials facilitated the subsequent picture naming. Neuroimaging results revealed greater activation in language-specific regions and domain-general multiple demand (MD) regions during higher lexical competition, reflecting their integrated role in managing cognitive demand. Neurally, transient cognitive control states did interact with lexical competition, albeit through competing mechanisms. Effective connectivity analyses further identified direct effects of MD regions on the activation of language regions. Additionally, individuals with lower cognitive control ability recruited additional neural domain-general resources to maintain the same level of performance as individuals with higher control ability. Overall, the results highlight how cognitive control states and traits dynamically modulate word production, through the interaction between domain-general and language networks.