Graded functional changes in ATL reflect both semantic content and process

Patients with semantic dementia have degraded conceptual knowledge, accompanied by atrophy of ATL; however, the organisation of ATL is less well-understood, due to signal loss/distortions in ATL in fMRI. We used MBME acquisition and the HCPex-Glasser parcellation to investigate how parcels within ATL respond across different types of semantic content (emotional, contextual, associative, feature) in generative and matching tasks. Areas closer to auditory cortex activated more for associative and emotion-based semantics. An intermediate area nearer to visual cortex was more multi-modal, with equal recruitment across judgments (associative/feature) and generation (emotion/context). The parcel closest to vision activated more for context than emotion. Recruitment was stronger for initial generation than switching to a second association, regardless of content, across ATL parcels. Left ATL activated more than right ATL across content and process (except aSTG). Our results are consistent with the graded-hub-perspective, showing graded transitions from both dorsal and medial ATL towards vATL.