LONG-TERM SYNAPTIC DEPRESSION IN THE MAMMALIAN BRAIN

A generally accepted hypothesis in neurobiology has been that at the cellular level, memories are stored, at least in part, as long-term alterations in the strength of synaptic transmission. In recent years, considerable attention has been paid to persistent, use-dependent mechanisms that increase synaptic strength, which are collectively referred to as long-term potentiation (LTP). This review shall examine the opposite phenomenon, use-dependent decreases in synaptic strength, or long-term depression (LTD). LTD is a broad term that is used to describe synaptic depression according to several different learning rules and in a wide variety of brain structures.