Why Do We Forget?

Memory isn’t static. How we remember an event or a situation is determined by a number of factors, including everything from our personal beliefs, attitudes and expectations to our feelings and emotions. Memories aren’t always permanent either — they can be replaced by other memories, or gradually disappear. This process is called forgetting, but why do we forget?

In principle, there are two answers to this question. One is that the memory has disappeared and, as such, can’t be retrieved, and the other is that the memory is still stored but not accessible. These two answers are based on some major theories of forgetting, namely encoding and retrieval failures, decay, displacement, interference, and lack of consolidation.

These theories, however, don’t explain every reason why memory fails us. There are many others, including absent-mindedness, suggestibility, misattribution, and much more serious ones, such as dementia.