OK, our memories are malleable. We can easily be made to misre-member, and easily be made to adopt memories of things that never happened. But what actually goes on in our brains as we code bad information? Can we see misinformation taking hold?
Researchers Yoko Okado and Craig Stark can.
They showed subjects slides (correct information), and then showed them another set of slides with details changed (incorrect information). And they watched as subjects’ hippocampi coded memories for both sets. Sure enough, the set of slides that most brightly lit subjects’ hippocampi is the set subjects remembered—whether correct or incorrect.
Next, Okado and Stark monitored the prefrontal cortex, which remembers the sources of our memories. If the PFC’s source tag was stronger for the fist set of slides, subjects thought that whatever they remembered had been shown in this first set. If the PFC lit brighter for the second set, subjects thought their information came from the second set.
Thus is a false memory born: The hippocampus remembers the wrong information and the prefrontal cortex believes it’s from the original scene.