8.3: Confidence and Accuracy

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Flashbulb Memories

Memories of some highly emotional moments seem particularly vivid and indelible; we are very certain that we accurately remember the details surrounding them. Most of you will have a clear and confident answer to the first question (and if you are old enough, to the other two as well).

Where were you when you learned about the Boston Marathon Bombing (April 15, 2013)? How did you hear about it? What else was going on around you then?
Where were you when you learned that two airplanes had crashed into the World Trade Center (September 11, 2001)? How did you hear about it? What else was going on around you then?
Where were you when you learned that the Challenger spacecraft had exploded (January 28, 1986)? How did you hear about it? What else was going on around you then?

The events are so dramatic that it feels like a mental flashbulb went off, freezing a snapshot of things indelibly in our minds.

How likely is it that your memory about how you learned of the bombing is mistaken? How would you feel if it turned out to be dramatically wrong?

The day after the Challenger disaster, the psychologists Ulric Neisser and N. Harsch asked a large group of undergraduates to write down where they were when they learned about it, who they heard it from, and so on.

Two and a half years later, these people were again interviewed about the setting in which they learned about the explosion. The accounts of over one third of the people were quite wrong, and another third were partly wrong. When they were shown the statements they wrote right after the explosion, many of the people were very distressed. Most of them preferred their recent account to the original one; they thought it more likely that they had been mistaken the day after the disaster than two and a half years later.

We are so confident of these memories that the possibility they could be distorted disturbs us. But it turns out that there is not a high correlation between the vividness of a person’s memory and its accuracy. Nor is there a high correlation between a person’s confidence in a memory and its accuracy. Confidence and vividness are very fallible indicators of the accuracy of a memory.