False Memories Under Fire: Surprising Science Behind What We Really Recall

New research challenges the ease of implanting false memories, highlighting flaws in the influential “Lost in the Mall” study.

By reexamining the data from a previous study, researchers found that many supposed false memories might actually be based on real experiences, casting doubt on the use of such studies in legal contexts.

Reevaluating the “Lost in the Mall” Study

False memories are much harder to implant than previously believed, according to a new study by researchers at UCL and Royal Holloway, University of London.

The 1995 “Lost in the Mall” study has been widely referenced in criminal trials, especially in cases of historical sexual abuse — most notably by Harvey Weinstein’s defense team — to question the reliability of accusers’ memories.

This well-known study suggested that implanting false memories of events that never happened is relatively easy. In the original study, 25% of the 24 participants falsely remembered being lost in a supermarket at the age of five.

In 2023, psychologists from University College Cork and University College Dublin replicated the study using the same methods but with a larger sample of 123 participants. They reported a higher rate of false memories, claiming that 35% of participants recalled the fabricated event.

Scrutiny of Recent Findings

However, a new analysis of the 2023 data, published in Applied Cognitive Psychology, has cast significant doubt on these findings. It revealed that none of the 35% classified as having a false memory fully recalled the fabricated event, and many did not even remember being lost at all.

According to the new analysis, half of those judged to have false memories had actually been lost before and were likely to be reporting on real events (albeit at a different time/place). Meanwhile, others were so unsure about the suggested details in the fake story that their testimony would have been of little value in court.

Implications for Legal Proceedings

Emeritus Professor Chris Brewin (UCL Psychology & Language Sciences) said: “The findings underscore the dangers of applying laboratory research findings to the real world of witnesses in court. People in these studies are cautious in what they claim to remember and seem to be much less likely than the investigators to agree they had a false memory. Experts need to be very careful in how they present research findings so as not to mislead the justice system.”

As part of their analysis, the researchers focused on six core details of the fake event, including: being lost; crying; being helped by an elderly woman; being reunited with their family; the location of the event; the time of the event.

Participant Reliability and Memory

They found that participants who were deemed to have a false memory on average recalled one and a half details with any confidence, and 30% recalled none at all.

This was consistent with previous reports that investigators’ false memory judgments were often not backed up by the views of the participants themselves.

Lead author Emeritus Professor Bernice Andrews (Royal Holloway Department of Psychology) added: “This is the first time that the raw data from a false memory implantation study have been made publicly available and subjected to independent scrutiny.”

Reference: “Lost in the Mall? Interrogating Judgements of False Memory” by Bernice Andrews and Chris R. Brewin, 12 December 2024, Applied Cognitive Psychology.
DOI: 10.1002/acp.70012