AI-like parallelogram geometry of word relations in the human neocortex

The same semantic relation (e.g., queen-king and woman-man) is encoded as a shared vector direction in language AI, forming parallelogram geometry, whereas its presence in the human brain remains unknown. Our fMRI analysis revealed similar geometry in the neocortex, particularly in higher-order language regions. Our findings link the brain and AI through a common geometry, advancing understanding of how abstract relational knowledge is organized and used in human language processing.