LONG-TERM MEMORY

Long term memory (or, for the acronym lovers, LTM) has a potentially limitless capacity. Or, it could be that there is a limit to it, and we just don't live long enough to discover that limit.

This is but one of the mysteries surrounding long term memory. Like all brain functions, modern science is busily at work to work out the technicalities of how we create, store, and recall memories. This much is known: long term memory is stored as meaning. This differs from short term memory, which stores an item for no longer than thirty seconds, is a temporary strengthening of neural connections. Neurobiologists believe short term memory becomes long term memory through a process of rehearsal and meaningful association. Through this process, what was a temporary strengthening of neural connections is repeated and "set" long enough that the actual structure of the neurons is physically changed. Once the neural connection is made more solid, long term memory can last from anywhere from thirty seconds to as long as decades and beyond.

Once established as long term, each memory is subject to fading, for assorted reasons, in the natural forgetting process. As such, multiple recalls or retrievals of a memory may be necessary for long term memories to last to their full potential. This also depends on the depth at which the memory is processed (how strong the neural connection becomes, through meaning and association). To put this all simply: long term memories are stored at a rate and depth dependant on the amount of meaning associated with the memory, and will last potentially all our lives, depending on how often and meaningfully we recall them. This recall can be deliberate or happen naturally, and is often dependent on our individually perceived importance of the material.