HIPPOCAMPAL MEMORY SYSTEM CONNECTIVITIES WITH ANTERIOR TEMPORAL SEMANTIC CORTEX FOR SEMANTIC LEARNING

The hippocampal episodic memory system is implicated in the learning of new semantic representations (Rolls et al. 2025). The aim is to describe the connectivity between the hippocampal system and the anterior temporal lobe semantic systems in humans using diffusion tractography, and functional and effective connectivity with Human Connectome Project data analysed with the HCP-Multimodal Parcellation.
The lateral parahippocampal cortex region TF has connectivity with the inferior temporal visual cortex involved in object and face representations; with the orbitofrontal cortex providing for reward value to be incorporated into memories; with the anterior temporal lobe semantic network including STSda, STSva, TE2a, and temporal pole TGd; with temporo-parieto-occipital junction regions TPOJ2 and TPOJ3 that are implicated in language; and with inferior frontal cortex regions IFSp and IFJa, which are highly connected with Broca's area regions 44 and 45.
The medial parahippocampal cortex regions PHA1-3 have connectivity with the ventromedial cortical visual pathway regions VMV1-3 and ProStriate Cortex; with TPOJ3, a semantic region; with inferior parietal PGs and some area 7 parietal regions for information about actions for semantic representations.
These resting state results have been extended to task-related functional and effective connectivity, which confirm and extend the results.
A theory and model is described for how these connectivities help the hippocampal episodic memory system to contribute to the learning of new semantic representations.
Rolls 2026. Brain Computations and Principles; and AI. Oxford University Press. Open Access.
Rolls et al 2025 Slow semantic learning in the cerebral cortex. Cerebral Cortex 35: bhaf107.