2026/05/20 by Rui Xu, Alan Bush, Atsushi Takahashi +20 · 1 voice
Neuroscience · #Connectome #Connectomics #Cortex (anatomy) #Face Recognition and Perception #Functional Brain Connectivity Studies #Functional connectivity #Functional magnetic resonance imaging #Functional organization #Human Connectome Project #Human brain #Neural dynamics and brain function
paper · doi:10.64898/2026.05.19.726279
published in bioRxiv (Cold Spring Harbor Laboratory) (Cold Spring Harbor Laboratory)
openalex publication_date 2026/05/20 · openalex created_date 2026/05/21 · openalex updated_date 2026/07/14
ABSTRACT The functional organization of human cortex has been mapped in considerable detail 1–5 , yet the axonal connections linking these areas remain largely unknown. This gap precludes inferring either the computational pathways through cortical networks or the principles governing why each area connects to its particular target regions. Here, in patients undergoing intracranial monitoring for epilepsy, we used concurrent electrical stimulation and functional magnetic resonance imaging (es-fMRI), validated previously against tracer studies in nonhuman primates 6 , to map anatomical connectivity of cortical sites across the whole brain, and combined these maps with task and resting-state fMRI in the same individuals. Es-fMRI revealed four main findings. First, connectivity followed an asymmetric functional-similarity principle: connected sites tended to share similar functional profiles, but, because connectivity is sparse, most pairs of functionally similar sites were not connected. Second, although connectivity also declines with distance 7 , the functional profile explained three times as much variance in connectivity as distance did, and long-range connections were the most functionally specific. Third, es-fMRI revealed direct monosynaptic links between established functional regions, including between the fusiform face area (FFA) 2 and the temporoparietal junction (TPJ) 3 for social cognition. Fourth, resting-state functional connectivity (rsFC) of a stimulation site was only weakly correlated with that site’s es-fMRI connectivity. Together, these results provide a first principled link between anatomical connectivity and functional organization in the human cortex, and establish es-fMRI as a scalable approach to building a tracer-grade connectome of the human brain.