# Bridging Continuous and Discrete Models of the Anterior Temporal Lobe via Cortical Gradients

## TL;DR

This paper investigates how the anterior temporal lobe is organized, finding that it likely follows a graded hub model with some discrete variations.

## Contribution

The study bridges continuous and discrete models of ATL organization by analyzing connectivity patterns across functional dimensions.

## Key findings

- ATL's structural and functional connectivity varies systematically along the heteromodal-unimodal dimension.
- Medial parcels in ATL show non-systematic deviations from expected connectivity patterns.
- Individual differences in structural connectivity predict task-related activation in auditory processing.

## Abstract

The anterior temporal lobe (ATL) is critical for semantic cognition, yet its organisation remains debated. Some evidence supports a patchwork of discrete, domain-specific parcels, while the graded hub hypothesis proposes smooth, ordered transitions. We examined regions along ATL’s curvature, testing whether connectivity profiles varied systematically or discontinuously along whole-brain dimensions of functional connectivity. The structural and functional connectivity of ATL varied largely systematically on the heteromodal-unimodal dimension, with intermediate ventral parcels showing stronger heteromodal connectivity; however, medial parcels deviated from this pattern. On the auditory-motor to visual dimension, there were partial dorsal-to-medial shifts in connectivity, but parcels at both ends did not follow this trend. There were also systematic dorsal-to-medial connectivity shifts between default and control networks. Individual differences in structural connectivity predicted activation in auditory tasks. These results largely support a graded hub model of ATL, while also revealing non-systematic functional variation that may enable flexible semantic processing.