Wait! What did I say last time?
We know eye witness recollections are not reliable but trusting eyewitnesses has just gotten worse! New research (from brain scientists, no less) tells us that our memory is altered with each retelling of a story. We’ve written before about how we may be “sure” we recall certain things that simply cannot be true.
New research out of the Journal of Neuroscience shows (for the first time) that the mere act of traveling back in your mind to a prior event can alter the recollection of what actually happened. Essentially, the study shows the first recitation of events occurring may be fairly accurate, but it goes downhill from there! While the research article looks at 12 subjects (9 women and 3 men)–an interview with the lead author reveals she has run variations on the study with 70 total participants. “Every single person has shown this effect. It’s really huge.”
The reality seems to be that our memories are not static–contrary to what we might believe. If you are in a new environment, a different mood, or tired (for example) you may recall things in a different way and that potential error is then incorporated into the memory itself. To verify this, the researchers measured the brain’s electrical activity and found that electrical signals in the brain were stronger when research participants were recalling a memory. Researchers believe the stronger brain signal indicated a new memory was being formulated and then future requests for repeating the same memory were contaminated. That is, memory error was encoded with the “real” memory and then was repeated in future retrieval efforts.
In other words, what is recalled about a memory may not be the memory itself but what we recalled on a subsequent telling or retelling! The article is written by brain scientists and published in a brain scientist journal. It’s a very tough read. You can find a more user-friendly write-up over at ScienceDaily.
One might argue that the research stimuli (a sort of brain scientist variation on the memory card game but with 180 pairs!) is not nearly as compelling as our memories of critical events. When events are meaningful to us we file them differently in our memories. Brain scientists would likely counter that memory is memory–and subsequent revisits to our recollections (whether of cards or landmark events in our lives) modifies our memories so that they ultimately are not retrievable in their actual how-it-really-happened form. It doesn’t seem that follow-up studies on more ‘memorable’ information (like witnessing an important event) would be too difficult, and it would certainly add to our understanding of how memories are recalled, reported, and maybe rewritten.
It raises questions about the importance of the idea of videotaping initial witnesses statements. If the memory in the moment is likely to be the most valid, subsequent changes and elaborations are more likely to be distortions. But what if the initial statement was made under stress? Or in a hurry? Or when the witness is distracted by circumstances?
According to this research, you may only think you recall that distant memory accurately. Instead, what you may hold dear is a recreated memory of what you wish had happened and now believe to be true. A more disturbing interpretation is taken from the evidence errors often found in false confessions cases. When witnesses hear that someone has confessed, they may (unknowingly) refine their recollection to support the believed-to-be true but false confession. And that is frightening indeed.
Bridge DJ, & Paller KA (2012). Neural correlates of reactivation and retrieval-induced distortion. The Journal of neuroscience : the official journal of the Society for Neuroscience, 32 (35), 12144-51 PMID: 22933797