title: Equalization of synaptic efficacy by synchronous neural activity.
abstract: It is commonly believed that spike timings of a postsynaptic neuron tend to follow those of the presynaptic neuron. Such orthodromic firing may, however, cause a conflict with the functional integrity of complex neuronal networks due to asymmetric temporal Hebbian plasticity. We argue that reversed spike timing in a synapse is a typical phenomenon in the cortex, which has a stabilizing effect on the neuronal network structure. We further demonstrate how the firing causality in a synapse is perturbed by synchronous neural activity and how the equilibrium property of spike-timing dependent plasticity is determined principally by the degree of synchronization. Remarkably, even noise-induced activity and synchrony of neurons can result in equalization of synaptic efficacy.
authors.affiliation: BK21 Frontier Physics Research Division, Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea.
authors.forename: Myoung Won
authors.initials: MW
authors.lastname: Cho
authors.forename: M Y
authors.initials: MY
authors.lastname: Choi
mesh_terms: D000200:Action Potentials / Q000502:physiology; D016571:Neural Networks, Computer; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D013569:Synapses / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology