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 easily be retrieved, but that specific cues might reactivate the memory.

Interference theory states that forgetting can be caused by competing memories. Retroactive interference occurs when new information interferes with the retrieval of old information, and proactive interference takes place 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 occurs when an event has not been encoded and stored in long-term memory.

See related concepts.