What affects the accuracy of memory?
Human memory is an amazing thing, but there are many ways memory
can fail. Here is a brief explanation of Daniel Schacter's "seven
sins of memory."
Three sins of forgetting:
- Encoding failure from absent-mindedness. If we paid attention
to every single detail it would be really overwhelming, so
oftentimes certain information never enters our long-term memories
and thus we cannot recall it later.
- Storage decay over time, which is called transience. Oftentimes
the memory we have successfully stored is just forgotten
later on. This is usually caused by lack of rehearsal (e.g. using
the Spanish vocabulary you learned three years ago) and a weakening
of neural connections.
- Blocking or retrieval failure. When we are given a lot of
similar information, we may store everything but it can be
difficult to recall one particular thing out of a large collection.
We learn a lot of names in our lives but cannot always remember
them all. New information can interfere with recalling old
information, and vice versa. Retrieval cues, such as seeing the
face of the person, may help.
Three sins of distortion:
- Misattribution. If you've ever thought Sally disliked chocolate
when it was really Hannah, you've misattributed your information.
When we encode memories, different aspects are distributed to the
part of the brain that deals with that type of info. In these
cases, the source part of the memory hasn't been sent
- False memories due to our suggestibility. Sometimes we are
given or imagine misinformation and incorporate it into our memory,
so later on we remember it as true.
- Bias can also distort our recollections. If students are given
cumbersome projects periodically throughout the year, they may
remember the teacher as tough or unfair despite having a lot of fun
in the class initially.
One sin of intrusion:
- Persistence of unwanted memories. If we are reliving memories
constantly, the theory would be that they stay accurate and fresh
in the mind. However there is a likelihood for our imaginations to
get away with us and exaggerate/add details - particularly with
unwanted or fear-inducing memories.