5. Organizational principles of semantic control in the human brain

COEX 

The human semantic system affords a multi-dimensional conceptual space through which we ascribe meaning to various words and objects around us. Notably, accessing concepts that are more remotely connected in this space is suggested to require higher levels of demand for semantic control [1]. However, the precise neural signature of semantic control, and its distributed organization within the cortical hierarchy remains unclear. By combining an fMRI-based semantic retrieval task [2], a natural language processing model [3] and multivoxel pattern analysis (MVPA) [4], here we captured a neural signature associated with varying demands for semantic control and charted its distribution within the cortical connectivity gradients [5]. We demonstrate that semantic control requires the engagement of multiple brain networks, dispersed along two principal gradients relevant to different aspects of semantic processing. This offers new insights into how the brain's functional networks are architecturally specialized to support semantic cognition.