Our memories are inaccurate, more than we’d like to believe. And now a study demonstrates one reason: we apparently add current experiences onto memories.
Study subjects examined the location of objects on a computer screen against a background of an underwater ocean scene. Researchers then showed the subjects a fresh screen with a different background, this time a photo of farmland. And the subjects had to place an object in the same position it was in on the original screen. And they always placed the object in the wrong position.
The researchers then presented three objects on the original ocean background. One was in the original location, another was in the location the subject just chose in the previous task and the third was in a new location. The subject was asked to pick the original location of the object in the original ocean background.
And instead of choosing the original correct location, they always picked the position they had chosen. That is, they now believed the position they’d picked on the farm scene was the original position on the ocean background. The study is in The Journal of Neuroscience. [Donna J. Bridge and Joel L. Voss, Hippocampal Binding of Novel Information with Dominant Memory Traces Can Support Both Memory Stability and Change]
The researchers note that recent and easily retrievable information “can overwrite what was there to begin with.” Consider that next time you hear eyewitness testimony.
[The above text is a transcript of this podcast.]