Long-Term Memory (LTM)

The third stage in an information-processing model of memory that proposes three distinct stages of memory, which differ in the length of time that information is stored. The first two stages are sensory memory and short-term (or working) memory. Long-term memory allows the information to be retained for periods of time beyond the capacity of short-term memory; some information is stored in long-term memory for days or weeks, but other information may remain across a lifetime, and the capacity of long-term memory is believed to be limitless. During REM (rapid eye movement) sleep and deep, slow-wave sleep, information from short-term memory is converted, through a process called consolidation, into long-term memories. Information can also be transferred from short-term to long-term memory through rehearsal, particularly elaborative rehearsal, since long-term memory depends largely on semantic coding (coding by meaning). Conceptual models of long-term memory posit that this memory system holds declarative and procedural memory and is organized according to semantic networks.