Neuronal PlasticityCerebellumLong-Term PotentiationSynapsesHippocampusSynaptic TransmissionLearningExcitatory Postsynaptic PotentialsNeuronsElectric StimulationRats, Sprague-DawleyTime FactorsLong-Term Synaptic DepressionDominance, OcularDendritic SpinesReceptors, N-Methyl-D-AspartateCritical Period (Psychology)Receptors, AMPAMemoryDendritesModels, Neurological