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bioRxiv · 10.64898/2026.02.13.705708

Temporo-Occipital and Medial Temporal Networks Underlying Object-Location Learning

Abstract

Object-location memory (OLM), a fundamental component of spatial memory, is essential for everyday functioning yet declines with aging and neurodegenerative disorders. Functional neuroimaging studies have consistently implicated medial temporal lobe (MTL) structures, including the hippocampus and parahippocampal gyrus, as well as medial and lateral temporo-occipital regions, in object-location associative learning. However, the neural mechanisms and functional network interactions supporting OLM acquisition remain largely unknown. To address this gap, we examined twenty healthy adults (18-45 years) performing an object-location learning task during functional MRI. As a first main finding, task-related functional connectivity analyses revealed enhanced coupling between MTL structures, ventral visual regions, and temporo-occipital cortices during OLM learning. Secondly, stronger connectivity within this network was associated with higher learning accuracy, highlighting the behavioral relevance of coordinated cortical-MTL interactions. Thirdly, these connectivity patterns were not static but evolved across learning stages: interregional coupling was strongest during early learning and progressively attenuated as performance stabilized, suggesting sharpening and increased efficiency of network interactions with learning. Together, our results provide mechanistic insight into OLM acquisition at the functional network level and offer an evidence-based framework for identifying target networks to enhance spatial memory through non-invasive brain stimulation.

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BibTeXRIS

Abdelmotaleb, M., Kocatas, H., Caisachana Guevara, L. M., Niemann, F., Shahbabaie, A., Kuhnke, P., Malinowski, R., Antonenko, D., Hartwigsen, G., Meinzer, M., Flöel, A.. 2026-02-16. Temporo-Occipital and Medial Temporal Networks Underlying Object-Location Learning. https://doi.org/10.64898/2026.02.13.705708

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