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Acetylcholine-modulated plasticity in reward-driven navigation: a computational study.

ABSTRACT: Neuromodulation plays a fundamental role in the acquisition of new behaviours. In previous experimental work, we showed that acetylcholine biases hippocampal synaptic plasticity towards depression, and the subsequent application of dopamine can retroactively convert depression into potentiation. We also demonstrated that incorporating this sequentially neuromodulated Spike-Timing-Dependent Plasticity (STDP) rule in a network model of navigation yields effective learning of changing reward locations. Here, we employ computational modelling to further characterize the effects of cholinergic depression on behaviour. We find that acetylcholine, by allowing learning from negative outcomes, enhances exploration over the action space. We show that this results in a variety of effects, depending on the structure of the model, the environment and the task. Interestingly, sequentially neuromodulated STDP also yields flexible learning, surpassing the performance of other reward-modulated plasticity rules.

SUBMITTER: Zannone S

PROVIDER: S-EPMC6013476 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Acetylcholine-modulated plasticity in reward-driven navigation: a computational study.

Zannone Sara S Brzosko Zuzanna Z Paulsen Ole O Clopath Claudia C

Scientific reports 20180621 1

Neuromodulation plays a fundamental role in the acquisition of new behaviours. In previous experimental work, we showed that acetylcholine biases hippocampal synaptic plasticity towards depression, and the subsequent application of dopamine can retroactively convert depression into potentiation. We also demonstrated that incorporating this sequentially neuromodulated Spike-Timing-Dependent Plasticity (STDP) rule in a network model of navigation yields effective learning of changing reward locati ...[more]

PMID: 29930322

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Dataset Information

Acetylcholine-modulated plasticity in reward-driven navigation: a computational study.

Publications

Acetylcholine-modulated plasticity in reward-driven navigation: a computational study.

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