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Synaptic Transmission Optimization Predicts Expression Loci of Long-Term Plasticity.

ABSTRACT: Long-term modifications of neuronal connections are critical for reliable memory storage in the brain. However, their locus of expression-pre- or postsynaptic-is highly variable. Here we introduce a theoretical framework in which long-term plasticity performs an optimization of the postsynaptic response statistics toward a given mean with minimal variance. Consequently, the state of the synapse at the time of plasticity induction determines the ratio of pre- and postsynaptic modifications. Our theory explains the experimentally observed expression loci of the hippocampal and neocortical synaptic potentiation studies we examined. Moreover, the theory predicts presynaptic expression of long-term depression, consistent with experimental observations. At inhibitory synapses, the theory suggests a statistically efficient excitatory-inhibitory balance in which changes in inhibitory postsynaptic response statistics specifically target the mean excitation. Our results provide a unifying theory for understanding the expression mechanisms and functions of long-term synaptic transmission plasticity.

SUBMITTER: Costa RP

PROVIDER: S-EPMC5626823 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Synaptic Transmission Optimization Predicts Expression Loci of Long-Term Plasticity.

Costa Rui Ponte RP Padamsey Zahid Z D'Amour James A JA Emptage Nigel J NJ Froemke Robert C RC Vogels Tim P TP

Neuron 20170901 1

Long-term modifications of neuronal connections are critical for reliable memory storage in the brain. However, their locus of expression-pre- or postsynaptic-is highly variable. Here we introduce a theoretical framework in which long-term plasticity performs an optimization of the postsynaptic response statistics toward a given mean with minimal variance. Consequently, the state of the synapse at the time of plasticity induction determines the ratio of pre- and postsynaptic modifications. Our t ...[more]

PMID: 28957667

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Dataset Information

Synaptic Transmission Optimization Predicts Expression Loci of Long-Term Plasticity.

Publications

Synaptic Transmission Optimization Predicts Expression Loci of Long-Term Plasticity.

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