Memory Reconsolidation is a process by which a memory can be returned to a labile (subject to change) state, after it has already entered long term memory.
For some time, the scientific consensus was that memory was only consolidated once, but there is now growing evidence for reconsolidation processes.
There is speculation that some therapies and change modalities work through the mechanism of memory reconsolidation, changing the emotional valence of memories by accessing them, bringing them to a labile state, then reconsolidating them.