Functional anatomy and topographical organization of the frontotemporal arcuate fasciculus

Traditionally, the frontotemporal arcuate fasciculus (AF) is viewed as a single entity in anatomo-clinical models. However, it is unclear if distinct cortical origin and termination patterns within this bundle correspond to specific language functions. We used track-weighted dynamic functional connectivity, a hybrid imaging technique, to study the AF structure and function in a large cohort of healthy participants. Our results suggest the AF can be subdivided based on dynamic changes in functional connectivity at the streamline endpoints. An unsupervised parcellation algorithm revealed spatially segregated subunits, which were then functionally quantified through meta-analysis. This approach identified three distinct clusters within the AF - ventral, middle, and dorsal frontotemporal AF - each linked to different frontal and temporal termination regions and likely involved in various language production and comprehension aspects.