Forgetting refers to the apparent loss of information already encoded and stored in an individual’s long term memory.
Theories of forgetting:
Cue-dependent forgetting or retrieval failure states that a memory is sometimes temporarily forgotten purely because it cannot be retrieved, but the proper cue can bring it to mind.
Interference theory states that forgetting can be caused by two competing memories. Retroactive interference happens when new information interferes with the retrieval of old information and proactive interference happens when old information interferes with the retrieval of new information.
Decay theory states that forgetting may occur due to memories fading with time.
Motivated forgetting may occur when there is something we would rather forget.
Encoding failure happens when we decide that an event or fact is not important, and not worthy of encoding and storing in long-term memory.