The Misinformation Effect

When you are in a relationship for a long time, you often tell stories together. Have you ever noticed how your story begins to change its mold as you retell it countless times at brunch? Perhaps it gets a little more dramatic, funnier, or scarier. Sometimes you and your partner might disagree on some of the details before agreeing on a middle ground. Other times you might recall the event with such great differences that you aren’t even sure your partner was there. “What are you talking about? You’re such a liar! We were in Montreal, not Toronto, and your mother wasn’t there, but the dog was.” However, both you and your partner could be telling the version that you wholeheartedly believe happened. One explanation for such occurrences is our mind’s tendency to experience the misinformation effect: when post-event information interferes with the original memory of an event.  

The misinformation effect: When our memory for past events is altered after exposure to misleading information.²

False memory: A memory of an event that is entirely false or partially distorted.

In the 1970s, researcher Elizabeth Loftus conducted a now-famous experiment on memory malleability using police tapes of car accidents.³ She showed the tape of a car crash and asked participants to predict the speed of the cars. In one condition, participants were asked about the cars’ speed after they “hit” each other; in another condition, participants were asked the same question using the word “smashed.” The group asked using the word “smashed” gave a higher speed prediction than the other participants and were more likely to incorrectly recall broken glass at the scene when interviewed a week later.

Since this study, research into the suggestibility of memory exploded. In 2005, Loftus published an overview spanning thirty years of memory research.²  Many researchers investigated which variables make the misinformation effect more likely to occur. One variable includes the duration of time since the event transpired: the effect is more likely when the passage of time allows the original memory to fade.³ Unsurprisingly, changing someone’s state (e.g. through hypnosis) can also increase the likelihood of the misinformation effect.⁴ Finally, age is another major variable: young children and the elderly are more susceptible, although studies on the latter group present conflicting results.^5,6 

Some researchers sought to find ways to prevent the misinformation effect. One solution involves warning people prior to receiving misinformation.² However, warning people after they’ve already been misinformed is less likely to help.²

Most people don’t appreciate how much misinformation can alter memory. In the 1990s, experiments suggested that even fully fake, traumatic false memories can be planted in someone’s mind, such as memories of animal attack or drowning.^7,8  Participants can even recite these false memories confidently and vividly.² Later studies suggested misinformation doesn’t always arise externally—we can misinform our own memories as we retrieve and reconstruct them.

Studies continue to explore the misinformation effect today, finding more factors that either promote or reduce the misinformation effect. One recent study found that post-learning stress can reduce the misinformation effect.¹⁰ While another study found that bilingual witnesses are more susceptible to the misinformation effect in their less proficient language.¹¹ Today, however, studies on misinformation aren’t limited to behavioral experiments but also attempt to understand the neural mechanisms that can explain the malleability of memory.

Studies investigating the misinformation effect are heavily applied in law. Since Loftus’s research, many legal scholars have questioned the validity of eyewitness testimonies since even minute misinformation before and during cross-examination can substantially alter witnesses’ memory. Psychologists began emphasizing the importance of following more careful protocols in police line-ups and interviews to avoid suggestibility.¹² One study found that crime reenactments used to elicit eyewitness accounts can contribute to the misinformation effect and should be avoided.¹³ A 2015 meta-analysis also demonstrated that enhancing the self-confidence of witnesses through a method called reinforced self-affirmation can significantly reduce the misinformation effect and suggested it be used in real cases.¹⁴

Within academia, critics of the misinformation effect often question the ethics of implanting false memories in subjects, especially if the subjects are children. In response, Loftus argued that follow-up studies have not revealed any adverse effects from participating in memory distortion studies. ¹⁵ The same critics who proclaimed ethical violations also criticized Loftus for exaggerating her work and misleading the public. Loftus addressed each criticism in 1999 and concluded the attack on her work seemed more personal than academically accurate.

Loftus also received great criticism from both the public and academics due to her frequent participation as an expert witness for the defense. Her research suggested that eyewitness accounts alone may not be sufficient for an accusation due to the malleability of memory. This sentiment became even more popular 1990s when DNA testing began uncovering convictions of innocent people, which were often based on eyewitness accounts.¹² While some applauded the value of misinformation research to promote a fair trial,  critics have stated the research was a tool used to discredit the experiences of women and promote complicity to the current institutions of power.^16,17  Some researchers argue Loftus should broaden her scope to present a more balanced opinion, such as discussing instances in which memory can be fairly accurate.

The criticisms grew stronger after Loftus responded to a wave of sexual abuse accusations based on previously suppressed memories. Loftus argued that little evidence supports the spontaneous recovery of memories and sparked worries that psychologists, through the power of suggestion, could implant traumatic memories into their patients’ minds. While investigating one case in which Loftus believed a mother was falsely accused of sexually abusing her daughter, Loftus was sued for defamation and an invasion of privacy.¹⁷

Opinions on Loftus vary dramatically depending on who you ask. She’s received death threats from survivors and good graces from the wrongfully convicted. Within academia, she’s experienced both estrangements from her colleagues and the highest academic honors. Loftus has claimed that “science belongs to all of us” and it doesn’t seem that any of the aforementioned controversies will stop her from conducting research or sharing her work with the public.¹⁶

Preventing Misinformation through Investigative Interviewing

As mentioned earlier, the effects of misinformation are particularly pronounced in children. For this reason, the National Institute for Child Health and Development (NICHD) created a protocol for interviewing children who have experienced traumatic events, which is a developmentally sensitive interviewing tool aimed at minimizing suggestibility effects. It emphasizes the use of open-ended questions and includes other procedures to ensure accurate reporting, such as a pre-emptive explanation that it is okay to not know the answer to the questions. In a 2020 study, researchers confirmed that conducting this interview process after an event protects children from incorporating misinformation into their accounts.¹⁸ The study emphasized that when children must discuss traumatic events, empirically validated interviewing is the most optimal approach.

The Misinformation Effect of Fake News

To test the effects of misinformation outside of the lab, researcher Gillian Murphy along with Loftus and their colleagues examined how eligible voters in the 2018 abortion referendum in Ireland would react to fabricated news articles.¹⁹ Participants were presented with news articles and asked to report whether they had any memories regarding the event. They were then told that some articles were fabricated and asked to identify the fakes.

Nearly half of the respondents claimed to remember a fabricated news article. They were more likely to remember a false memory about the opposing side and many failed to reconsider despite being told the articles could be fake. This study is proof that the misinformation effect occurs quickly and frequently in the real world, an issue researchers warn will only worsen with the proliferation of technology. It seems that Loftus’s research will continue to stay relevant for years to come

How To Fight Fake News With Behavioral Science

Most people would agree misinformation effects caused by fake news is one of the most pressing issues of our time. This TDL article describes how behavioral science can help separate fact from fiction and overcome blind spots in information processing.

How do our memories differ from our experiences?

The misinformation effect is only one of the many ways our memories of the past become distorted. The peak-end rule is a psychological heuristic that describes another mechanism of misremembering. The peak-end rule describes our tendency to remember an event or judge an experience based on how it felt at the peak moments, as well as the end. Read this article to learn more about the pleasant and unfortunate ways this bias shapes our memories.

The Human Error behind Fake News with David Rand

What’s the difference between disinformation and misinformation? Misinformation expert David Rand sits down with the TDL’s Research Director, Brooke, to discuss the role of behavior in the perpetuation of false information online.

1. Causes of wrongful convictions. Innocence Canada. (n.d.). https://www.innocencecanada.com/causes-of-wrongful-convictions/.
2.     Loftus, E. F. (2005). Planting misinformation in the human mind: A 30-year investigation of the malleability of memory. Learning & Memory, 12(4), 361–366. https://doi.org/10.1101/lm.94705
3.     Loftus, E. F., Miller, D. G., & Burns, H. J. (1978). Semantic integration of verbal information into a visual memory. Journal of Experimental Psychology: Human Learning and Memory, 4(1), 19–31. https://doi.org/10.1037/0278-7393.4.1.19
4.     Scoboria, A., Mazzoni, G., Kirsch, I., & Milling, L. S. (2002). Immediate and persisting effects of misleading questions and hypnosis on memory reports. Journal of Experimental Psychology: Applied, 8(1), 26–32. https://doi.org/10.1037/1076-898x.8.1.26
5.     Ceci, S. J., & Bruck, M. (1993). Suggestibility of the child Witness: A historical review and synthesis. Psychological Bulletin, 113(3), 403–439. https://doi.org/10.1037/0033-2909.113.3.403
6.     Karpel, M. E., Hoyer, W. J., & Toglia, M. P. (2001). Accuracy and qualities of real and suggested memories: Nonspecific age differences. The Journals of Gerontology Series B: Psychological Sciences and Social Sciences, 56(2). https://doi.org/10.1093/geronb/56.2.p103
7.     Porter, S., Yuille, J. C., & Lehman, D. R. (1999). The nature of real, implanted, and fabricated memories for emotional childhood events: Implications for the recovered memory debate. Law and Human Behavior, 23(5), 517–537. https://doi.org/10.1023/a:1022344128649
8.     Heaps, C. M., & Nash, M. (2001). Comparing recollective experience in true and false autobiographical memories. Journal of Experimental Psychology: Learning, Memory, and Cognition, 27(4), 920–930. https://doi.org/10.1037/0278-7393.27.4.920
9.     Zagorski, N. (2005). Profile of Elizabeth F. loftus. Proceedings of the National Academy of Sciences, 102(39), 13721–13723. https://doi.org/10.1073/pnas.0506223102
10. Nitschke, J. P., Chu, S., Pruessner, J. C., Bartz, J. A., & Sheldon, S. (2019). Post-learning stress reduces the misinformation effect: Effects of psychosocial stress on memory updating. Psychoneuroendocrinology, 102, 164–171. https://doi.org/10.1016/j.psyneuen.2018.12.008
11. Calvillo, D. P., & Mills, N. V. (2018). Bilingual witnesses are more susceptible to the misinformation effect in their less Proficient language. Current Psychology, 39(2), 673–680. https://doi.org/10.1007/s12144-018-9787-9
12. Quigley-McBride, A., Smalarz, L., Wells, G., Quigley-McBride, A., Smalarz, L., & Wells, G. (2011). Eyewitness testimony. Oxford Bibliographies Online Datasets. https://doi.org/10.1093/obo/9780199828340-0026
13. Cullen, H. J., Paterson, H. M., & van Golde, C. (2020). Stopping crime? The effect of crime re-enactments on eyewitness memory. Psychiatry, Psychology and Law, 1–24. https://doi.org/10.1080/13218719.2020.1775151
14. Szpitalak, M., & Polczyk, R. (2019). Inducing resistance to the misinformation effect by means of reinforced self-affirmation: The importance of positive feedback. PLOS ONE, 14(1). https://doi.org/10.1371/journal.pone.0210987
15. Loftus, E. F. (1999). Lost in the Mall: Misrepresentations and misunderstandings. Ethics & Behavior, 9(1), 51–60. https://doi.org/10.
16. Newberry, L. (2020, February 6). This ‘false memory’ expert has testified in hundreds of Trials. now she’s been hired by Harvey Weinstein. Los Angeles Times. https://www.latimes.com/california/story/2020-02-06/false-memory-expert-testify-harvey-weinstein-trial
17. Aviv, R. (2021, March 26). How Elizabeth loftus changed the meaning of memory. The New Yorker. https://www.newyorker.com/magazine/2021/04/05/how-elizabeth-loftus-changed-the-meaning-of-memory.
18. Otgaar, H., de Ruiter, C., Sumampouw, N., Erens, B., & Muris, P. (2020). Protecting against misinformation: Examining the effect of empirically based investigative interviewing on misinformation reporting. Journal of Police and Criminal Psychology. https://doi.org/10.1007/s11896-020-09401-2
19. Murphy, G., Loftus, E. F., Grady, R. H., Levine, L. J., & Greene, C. M. (2019). False memories for fake news during ireland’s abortion referendum. Psychological Science, 30(10), 1449–1459. https://doi.org/10.1177/0956797619864887