Synaptic modification of transmission is a general phenomenon expressed at al-most every excitatory synapse in the mammalian brain.Over the last three decades,much has been discovered about the cellular,synaptic,molecular,and signalingmechanisms responsible for controlling synaptic transmission and plasticity.Here,we present a brief review of these mechanisms with emphasis on the currentunderstanding of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid recep-tor (AMPA-R) trafficking and Ras-mitogen-activated protein kinase (MAPK)signaling events involved in controlling synaptic transmission. Synaptic modification of transmission is a general response expressed in al-most every excitatory synapse in the mammalian brain. Over the last three decades, much has been discovered about the cellular, synaptic, molecular, and signaling mechanisms responsible for controlling synaptic transmission and plasticity. Here , we present a brief review of these mechanisms with emphasis on the current understanding of a-amino-3-hydroxy-5-methyl- 4-isoxazole propionic acid recep-tor (AMPA-R) trafficking and Ras-mitogen- activated protein kinase MAPK) signaling events involved in controlling synaptic transmission.