The Brain’s Updating Mechanisms Can Create False Memories
By: Sai Srihaas Potu
We remember a considerable number of personal experiences because we are frequently reminded of them, a process known as memory reactivation. Although memory reactivation helps to stabilize and update memories, reactivation may also introduce distortions if novel information becomes incorporated with memory.
Two recent studies have shown that the brain can update poorly formed memories with incorrect information, leading to the creation of false memories.
Reactivation is a key process that updates memory by strengthening existing memories and incorporating relevant new information, thus supporting the dynamic and flexible nature of memory. This adaptive function, however, can sometimes contribute to memory distortions. The first study examined how neural mechanisms that operate during reactivation of memories contribute to the enhancement of existing memories, while also supporting the integration of novel information that can contribute to false memories.
The results revealed the similarities and differences in the neural mechanisms of reactivation associated with subsequent true and false memories for real-world events, thereby illuminating how memories change over time as a consequence of reactivation—a process that has important implications for understanding the unreliability of eyewitness memories. They also showed that the quality of reactivation modulated subsequent true and false memories via recruitment of left posterior parahippocampal, bilateral retrosplenial, and bilateral posterior inferior parietal cortices. Ultimately, these results reveal the neural mechanisms recruited during memory reactivation that modify how memories will be subsequently retrieved, supporting the flexible and dynamic aspects of memory.
The second study analyzed the effects of novel behavioral, molecular, and computational techniques to investigate memories that have not been well-formed, and how the brain deals with them.
The 6-year study shows that the same mechanism that updates poor memories can also severely distort them if it occurs in the wrong situation.
Professor Vissel, from the UTS Centre for Neuroscience & Regenerative Medicine, said these findings could be useful for understanding memory fallibility in everyday life; fear and memory disorders, post-traumatic stress disorder (PTSD); and situations where accurate recall is critical, like witness testimony in courtrooms.
Research in the field of neuroscience supports the idea that memory is not an exact reproduction of past experiences, but is instead a constructive process subject to a variety of errors and distortions. Both in the laboratory and everyday life, much evidence shows that people sometimes remember events differently from the way they unfolded and under some conditions remember events that never happened. Memory distortions can have serious consequences in everyday life, as we see one a day to day basis, and need to be taken seriously to protect the people harmed and those around them.
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