This post is a continuation of “The Experience Wall” series of posts. You can check out the first 2 posts here and here. In the first post I spoke generally about experience and broke it up into 3 parts.
1) The perception of clinical events (seeing, hearing, feeling, etc)
2) The memories of those events
3) The interpretation of those perceptions (cause and effect, etc)
This post will look at memories in more detail.
Just like with perception, it is easy to feel that our memories are accurate and unaffected by our biases. However it turns out that memory is often inaccurate and influenced by beliefs, biases and perspective. In this article and this book Daniel Schacter describes “The seven sins of memory” These seven sins describe 7 ways our memories fail us.
Sometimes these failures of our memory are very obvious. For example, forgetting the name of someone you have not seen in years or losing your car in a mall parking lot. Other times, errors in memory go undetected. These hidden errors have been highlight by lost in the mall studies. These studies expose a person to fictitious stories about them being lost in the mall as a child. After hearing this enough times (often told by relatives) they adopt the memory and truly remember that it happened (even though it didn’t), sin #5.
These hidden errors in memory are dangerous because we are often very confident that our memory is accurate, even though it is not. This over confidence can lead to serious errors, such as those seen with eye witness testimony. The confident testimony of eye witnesses has resulted in numerous convictions, which have later been overturned by more objective information, such as DNA analysis.
These examples demonstrate that memory is incomplete, constructed after events and continually influenced and changed by our current needs, biases and expectations. Furthermore, extreme confidence in a memory is not strongly correlated with the accuracy of those memories.
Memory of past patients and past outcomes makes up a big part of clinical experience. We use our recollection of past cases to make judgments on diagnosis, prognosis and treatment effectiveness. Unfortunately, we may be more likely to remember patients who got better and less likely to remember those who did not (or vice versa). This can leave us with a skewed and biased view of our past performance. For example, a clinician may remember that in the past “correcting” an anteriorly rotated pelvis has been very effective. However, due to bias or other errors of memory, the clinician may have forgotten all of the cases in which this “correction” did not work.
As with errors in perception, errors of memory cannot be avoided. We have to understand that our recall of events is imperfect and adjust our confidence in memory accordingly.