Mestres Missé, A. , Turner, R. & Friederici, A. D.
Max Planck Institute for Human Cognitive and Brain Sciences
Lateral prefrontal cortex and basal ganglia work together to mediate working memory and top-down regulation of cognition. This system regulates the balance and interactions between automatic and high-order control responses. Using ultra-high-field high-resolution functional magnetic resonance imaging (fMRI), the present study examined the role of subcortical structures in cognitive control during language processing in humans. Participants were asked to judge the grammaticality of ambiguous, unambiguous and ungrammatical sentences. Unambiguous sentences require an automatic response, while ambiguous and ungrammatical sentences conflict with the automatic response and, hence, require a high-order control response. Furthermore, ambiguity and ungrammaticality represent two different dimensions of conflict resolution, while for ambiguity a correct alternative is available, that is not the case for ungrammaticality. The results reveal a rostroventral-caudodorsal axis in the head of the caudate nucleus with more rostroventral regions supporting higher levels of cognitive processing. This functional architecture mirrors the rostrocaudal hierarchical organization within the prefrontal cortex.