Decoding the functional architecture of the inferior fronto-occipital fasciculus: a multimodal neuroimaging approach.

The inferior fronto-occipital fasciculus (IFOF) is a prominent long-range association pathway connecting occipital cortex with prefrontal regions, including dorsolateral, ventrolateral, and orbitofrontal cortices. Growing clinical and cognitive neuroscience evidence implicates the IFOF in a variety of functions requiring integration of visual information with higher-order processing, such as semantic retrieval, emotion recognition, and reading. Emerging models suggest that the IFOF exhibits a functional gradient along its ventral-to-dorsal extent, spanning from perceptual to conceptual processing domains. However, the internal functional organization of the IFOF remains scarcely characterized. In this study, we systematically investigated the functional topography of the IFOF using an novel multimodal neuroimaging framework. We integrated tractography from di.usion MRI with dynamic connectivity analyses derived from resting-state fMRI, using data from two independent, high-quality datasets that include repeated scanning sessions. Additionally, we introduce a novel method to project large-scale, meta-analytic taskfMRI activation maps onto white matter tracts, allowing inference of cognitive domains associated with speci!c subregions of the IFOF.