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A stochastic model of hippocampal synaptic plasticity with geometrical readout of enzyme dynamics.

ABSTRACT: Discovering the rules of synaptic plasticity is an important step for understanding brain learning. Existing plasticity models are either (1) top-down and interpretable, but not flexible enough to account for experimental data, or (2) bottom-up and biologically realistic, but too intricate to interpret and hard to fit to data. To avoid the shortcomings of these approaches, we present a new plasticity rule based on a geometrical readout mechanism that flexibly maps synaptic enzyme dynamics to predict plasticity outcomes. We apply this readout to a multi-timescale model of hippocampal synaptic plasticity induction that includes electrical dynamics, calcium, CaMKII and calcineurin, and accurate representation of intrinsic noise sources. Using a single set of model parameters, we demonstrate the robustness of this plasticity rule by reproducing nine published ex vivo experiments covering various spike-timing and frequency-dependent plasticity induction protocols, animal ages, and experimental conditions. Our model also predicts that in vivo-like spike timing irregularity strongly shapes plasticity outcome. This geometrical readout modelling approach can be readily applied to other excitatory or inhibitory synapses to discover their synaptic plasticity rules.

SUBMITTER: Rodrigues YE

PROVIDER: S-EPMC10435238 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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A stochastic model of hippocampal synaptic plasticity with geometrical readout of enzyme dynamics.

Rodrigues Yuri Elias YE Tigaret Cezar M CM Marie Hélène H O'Donnell Cian C Veltz Romain R

eLife 20230817

Discovering the rules of synaptic plasticity is an important step for understanding brain learning. Existing plasticity models are either (1) top-down and interpretable, but not flexible enough to account for experimental data, or (2) bottom-up and biologically realistic, but too intricate to interpret and hard to fit to data. To avoid the shortcomings of these approaches, we present a new plasticity rule based on a geometrical readout mechanism that flexibly maps synaptic enzyme dynamics to pre ...[more]

PMID: 37589251

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A stochastic model of hippocampal synaptic plasticity with geometrical readout of enzyme dynamics.

Publications

A stochastic model of hippocampal synaptic plasticity with geometrical readout of enzyme dynamics.

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