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bioRxiv · 10.1101/2025.07.03.663054

Long-Term Potentiation and Closed-Loop Learning in Paired Brain Organoids for CNS Drug Discovery

Rountree, C.·Schmidt, E.·Coungeris, N.·Alstat, V.·LaCroix, A. S.·Morris, M.·Moore, M. J.·Curley, J. L.
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Abstract

Learning and memory, central to cognitive function and critical targets for drug discovery in neurological disorders, fundamentally rely on synaptic plasticity, such as long-term potentiation (LTP). We developed an embedded electrode array (EEA) capable of supporting paired CNS-3D brain organoids, derived from human, induced pluripotent stem cells (iPSCs), that were interconnected via guided axonal growth, as a novel functional biomarker model for probing learning-related plasticity in vitro. Using open-loop stimulation protocols, a robust, network-level LTP in trained organoids was demonstrated that was not observed in untrained organoids. Importantly, LTP was enhanced in the presence of elevated levels of brain-derived neurotrophic factor (BDNF), and it was prevented by the NMDA receptor antagonist AP5. Furthermore, a closed-loop "maze-game", inspired by Pac-Man(R), demonstrated that paired brain organoids could learn to perform better in the game when given reinforcement feedback, and that this effect depended on BDNF. This integrated platform provides a human-relevant in vitro model of synaptic plasticity and cognitive function, establishing a functional biomarker platform for central nervous system (CNS) drug discovery and linking game performance as a measurable readout of learning-related plasticity to the emerging field of organoid intelligence.

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Rountree, C., Schmidt, E., Coungeris, N., Alstat, V., LaCroix, A. S., Morris, M., Moore, M. J., Curley, J. L.. 2025-07-07. Long-Term Potentiation and Closed-Loop Learning in Paired Brain Organoids for CNS Drug Discovery. https://doi.org/10.1101/2025.07.03.663054

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