Fool me twice: how effective is debriefing in false memory studies?

Unringing the bell: Successful debriefing following a rich false memory study

In rich false memory studies, familial informants often provide information to support researchers in planting vivid memories of events that never occurred. The goal of the current study was to assess how effectively we can retract these false memories via debriefing - i.e., to what extent can we put participants back the way we found them? We aimed to establish (1) what proportion of participants would retain a false memory or false belief following debriefing, and (2) whether richer, more detailed memories would be more difficult to retract. Participants (N = 123) completed a false memory implantation protocol as part of a replication of the "Lost in the Mall" study (Loftus & Pickrell, Psychiatric Annals, 25, 720-725, 1995). By the end of the protocol, 14% of participants self-reported a memory for the fabricated event, and a further 52% believed it had happened. Participants were then fully debriefed, and memory and belief for the false event were assessed again. In a follow-up assessment 3 days post-debriefing, the false memory rate had dropped to 6% and false belief rates also fell precipitously to 7%. Moreover, virtually all persistent false memories were found to be nonbelieved memories, where participants no longer accepted that the fabricated event had occurred. Richer, more detailed memories were more resistant to correction, but were still mostly retracted. This study provides evidence that participants can be "dehoaxed", and even very convincing false memories can be retracted.

Conducting ethical misinformation research: Deception, dialogue, and debriefing

Misinformation research can present many ethical challenges to researchers. These challenges are not insurmountable, but recent research suggests that as a field, we should be adopting and reporting stronger ethical practices. In this review, we consider the three D's of ethical misinformation research; the need to balance deception with informed consent, the value of maintaining an open dialogue with research participants to gather their insights and perspectives, and perhaps most importantly, the essential requirement for effective post-experimental debriefing. We make some specific and straightforward recommendations for misinformation researchers to increase the visibility of their ethical practices and outline the benefits for individual researchers and for the field.

Face/Off: Changing the face of movies with deepfakes

There are growing concerns about the potential for deepfake technology to spread misinformation and distort memories, though many also highlight creative applications such as recasting movies using other actors, or younger versions of the same actor. In the current mixed-methods study, we presented participants (N = 436) with deepfake videos of fictitious movie remakes (such as Will Smith staring as Neo in The Matrix). We observed an average false memory rate of 49%, with many participants remembering the fake remake as better than the original film. However, deepfakes were no more effective than simple text descriptions at distorting memory. Though our findings suggest that deepfake technology is not uniquely placed to distort movie memories, our qualitative data suggested most participants were uncomfortable with deepfake recasting. Common concerns were disrespecting artistic integrity, disrupting the shared social experience of films, and a discomfort at the control and options this technology would afford.

How do participants feel about the ethics of rich false memory studies?

ABSTRACTDeception is often a necessity in rich false memory studies, but is this deception acceptable to participants? In the current study, we followed up with 175 participants who had taken part in a replication of the Lost in the Mall childhood false memory study (Loftus & Pickrell, 1995), as either a research subject or a familial informant. We found that both participants and informants were generally very positive about their experience, did not regret taking part and found the deceptive methods acceptable. Importantly, the vast majority reported that they would still have taken part had they known the true objectives from the beginning. Participants also reported learning something interesting about memory and enjoying the nostalgia and family discussions that were prompted by the study. We would encourage other researchers to assess the ethical implications of false memory research paradigms and to incorporate the valuable feedback from participants and informants.

Debriefing works: Successful retraction of misinformation following a fake news study

In recent years there has been an explosion of research on misinformation, often involving experiments where participants are presented with fake news stories and subsequently debriefed. In order to avoid potential harm to participants or society, it is imperative that we establish whether debriefing procedures remove any lasting influence of misinformation. In the current study, we followed up with 1547 participants one week after they had been exposed to fake news stories about COVID-19 and then provided with a detailed debriefing. False memories and beliefs for previously-seen fake stories declined from the original study, suggesting that the debrief was effective. Moreover, the debriefing resulted in reduced false memories and beliefs for novel fake stories, suggesting a broader impact on participants' willingness to accept misinformation. Small effects of misinformation on planned health behaviours observed in the original study were also eliminated at follow-up. Our findings suggest that when a careful and thorough debriefing procedure is followed, researchers can safely and ethically conduct misinformation research on sensitive topics.

Partisan bias in false memories for misinformation about the 2021 U.S. Capitol riot

ABSTRACTMemory for events can be biased. For example, people tend to recall more events that support than oppose their current worldview. The present study examined partisan bias in memory for events related to the January 6, 2021, Capitol riot in the United States. Participants rated their memory for true and false events that were either favourable to their political party or the other major political party in the United States. For both true and false events, participants remembered more events that favoured their political party. Regression analyses showed that the number of false memories that participants reported was positively associated with their tendency to support conspiracy beliefs and with their self-reported engagement with the Capitol riot. These results suggest that Democrats and Republicans remember the Capitol Riot differently and that certain individual difference factors can predict the formation of false memories in this context. Misinformation played an influential role in the Capitol riot and understanding differences in memory for this event is beneficial to avoiding similar tragedies in the future.

A single exposure to cancer misinformation may not significantly affect related behavioural intentions

Background: In recent years, rates of online cancer misinformation have grown, with many concerned that this could lead patients to alter their daily behaviours or forego conventional treatment. However, no published study has investigated whether exposure to cancer misinformation can affect health behaviours or behavioural intentions. Method: In this preregistered study, participants (N = 774) were exposed to cancer misinformation in the form of news stories before rating their intentions to engage in related behaviours. Each participant was randomly presented with two of four possible false cancer headlines such as “Drinking fluoridated water shown to increase cancer risk by a factor of 3”, before rating their intentions to engage in certain behaviours (such as avoiding fluoridated water). Participants were also randomly assigned to either an accuracy-nudge intervention intended to reduce susceptibility to misinformation or a control condition with no intervention. Results: Viewing the fake cancer headlines did not significantly affect participants’ behavioural intentions – e.g., those who saw the headline regarding fluoridated water were not more likely to report intentions to reduce their fluoridated water intake. The accuracy-nudge intervention did not affect behavioural intentions. Conclusion: Although cancer misinformation is considered a threat to public health, we conclude that once-off exposures to cancer misinformation may not be sufficient to significantly alter behavioural intentions. We note that claims about the effects of cancer misinformation on behaviour have not been adequately researched and we therefore call for more research into the behavioural effects of cancer misinformation exposure, particularly repeated exposure or information passed from trusted sources.

Best Practices for Ethical Conduct of Misinformation Research

Abstract. Misinformation can have noxious impacts on cognition, fostering the formation of false beliefs, retroactively distorting memory for events, and influencing reasoning and decision-making even after it has been credibly corrected. Researchers investigating the impacts of real-world misinformation are therefore faced with an ethical issue: they must consider the immediate and long-term consequences of exposing participants to false claims. In this paper, we first present an overview of the ethical risks associated with real-world misinformation. We then report results from a scoping review of ethical practices in misinformation research. We investigated (1) the extent to which researchers report the details of their ethical practices, including issues of informed consent and debriefing, and (2) the specific steps that researchers report taking to protect participants from the consequences of misinformation exposure. We found that fewer than 30% of misinformation papers report any debriefing, and almost no authors assessed the effectiveness of their debriefing procedure. Building on the findings from this review, we evaluate the balance of risk versus reward currently operating in this field and propose a set of guidelines for best practices. Our ultimate goal is to allow researchers the freedom to investigate questions of considerable scientific and societal impact while meeting their ethical obligations to participants.

Memories people no longer believe in can still affect them in helpful and harmful ways

People can come to “remember” experiences they never had, and these false memories—much like memories for real experiences—can serve a variety of helpful and harmful functions. Sometimes, though, people realize one of their memories is false, and retract their belief in it. These “retracted memories” continue to have many of the same phenomenological characteristics as their believed memories. But can they also continue to serve functions? Across four experiments, we asked subjects to rate the extent to which their retracted memories serve helpful and harmful functions and compared these functions with those served by “genuine” autobiographical memories. People rated their retracted memories as serving both helpful and harmful functions, much like their genuine memories. In addition, we found only weak relationships between people’s belief in their memories and the extent to which those memories served perceived functions. These results suggest memories can serve functions even in the absence of belief and highlight the potential for false memories to affect people’s thinking and behavior even after people have retracted them.

What happens after debriefing? The effectiveness and benefits of postexperimental debriefing

After participating in an experiment, people are routinely debriefed. How effective is debriefing when the experiments involve deception, as occurs in studies of misinformation and memory? We conducted two studies addressing this question. In Study 1, participants (N = 373) watched a video, were exposed to misinformation or not, and completed a memory test. Participants were either debriefed or not and then were interviewed approximately one week later. Results revealed that, after debriefing, some participants continued to endorse misinformation. Notably, however, debriefing had positive effects; participants exposed to misinformation reported learning significantly more from their study participation than control participants. In Study 2 (N = 439), we developed and tested a novel, enhanced debriefing. The enhanced debriefing included more information about the presence of misinformation in the study and how memory errors occur. This enhanced debriefing outperformed typical debriefing. Specifically, when the enhanced debriefing explicitly named and described the misinformation, the misinformation effect postdebriefing was eliminated. Enhanced debriefing also resulted in a more positive participant experience than typical debriefing. These results have implications for the design and use of debriefing in deception studies.

Push polls increase false memories for fake news stories

Push polls are an insidious means of disseminating information under the guise of a legitimate information-gathering poll (e.g., "Would you be more or less likely to vote for X if you heard they were being investigated for tax fraud?"). While previous research has shown that push polls can affect attitudes, the current study assessed whether exposure to push polls can increase false memories for corresponding fake news stories. Across four studies, we found that participants (N = 1,290) were significantly more likely to report a false memory for a corresponding fabricated news story after push poll exposure. This was true for positive and negative stories, concerning both fictitious characters and well-known public figures. Furthermore, this effect was stronger after a delay of one week between the push poll and the news story. Our findings suggest that push polls are a potent applied example of the misinformation effect and can significantly increase susceptibility to fake news stories.

Deepfake false memories

Machine-learning has enabled the creation of "deepfake videos"; highly-realistic footage that features a person saying or doing something they never did. In recent years, this technology has become more widespread and various apps now allow an average social-media user to create a deepfake video which can be shared online. There are concerns about how this may distort memory for public events, but to date no evidence to support this. Across two experiments, we presented participants (N = 682) with fake news stories in the format of text, text with a photograph or text with a deepfake video. Though participants rated the deepfake videos as convincing, dangerous, and unethical, and some participants did report false memories after viewing deepfakes, the deepfake video format did not consistently increase false memory rates relative to the text-only or text-with-photograph conditions. Further research is needed, but the current findings suggest that while deepfake videos can distort memory for public events, they may not always be more effective than simple misleading text.

Remembering facts versus feelings in the wake of political events

Amid rising political polarisation, inaccurate memory for facts and exaggerated memories of grievances can drive individuals and groups further apart. We assessed whether people with more accurate memories of the facts concerning political events were less susceptible to bias when remembering how events made them feel. Study 1 assessed participants' memories concerning the 2016 U.S. presidential election (N = 571), and included 33 individuals with Highly Superior Autobiographical Memory (HSAM). Study 2 assessed participants' memories concerning the 2018 referendum on abortion in Ireland (N = 733). Participants rated how happy, angry, and scared they felt days after these events. Six months later, they recalled their feelings and factual information. In both studies, participants overestimated how angry they had felt but underestimated happiness and fear. Adjusting for importance, no association was found between the accuracy of memory for facts and feelings. Accuracy in remembering facts was predicted by media exposure. Accuracy in remembering feelings was predicted by consistency over time in feelings and appraisals about past events. HSAM participants in Study 1 remembered election-related facts better than others, but not their feelings. Thus, having a good grasp of the facts did not protect against bias in remembering feelings about political events.

Rich false memories of autobiographical events can be reversed

False memories of autobiographical events can create enormous problems in forensic settings (e.g., false accusations). While multiple studies succeeded in inducing false memories in interview settings, we present research trying to reverse this effect (and thereby reduce the potential damage) by means of two ecologically valid strategies. We first successfully implanted false memories for two plausible autobiographical events (suggested by the students' parents, alongside two true events). Over three repeated interviews, participants developed false memories (measured by state-of-the-art coding) of the suggested events under minimally suggestive conditions (27%) and even more so using massive suggestion (56%). We then used two techniques to reduce false memory endorsement, source sensitization (alerting interviewees to possible external sources of the memories, e.g., family narratives) and false memory sensitization (raising the possibility of false memories being inadvertently created in memory interviews, delivered by a new interviewer). This reversed the false memory build-up over the first three interviews, returning false memory rates in both suggestion conditions to the baseline levels of the first interview (i.e., to ∼15% and ∼25%, respectively). By comparison, true event memories were endorsed at a higher level overall and less affected by either the repeated interviews or the sensitization techniques. In a 1-y follow-up (after the original interviews and debriefing), false memory rates further dropped to 5%, and participants overwhelmingly rejected the false events. One strong practical implication is that false memories can be substantially reduced by easy-to-implement techniques without causing collateral damage to true memories.

Individual differences in susceptibility to false memories for COVID-19 fake news

Exposure to 'fake news' can result in false memories, with possible consequences for downstream behaviour. Given the sharp rise in online misinformation during the coronavirus pandemic, it is important to understand the factors that influence the development of false memories. The present study measured susceptibility to false memories following exposure to fabricated news stories about the pandemic in a sample of 3746 participants. We investigated the effect of individual differences in (1) knowledge about COVID-19, (2) engagement with media or discussion about the coronavirus, (3) anxiety about COVID-19 and (4) analytical reasoning. Notably, objectively and subjectively assessed knowledge about COVID-19 were not significantly correlated. Objectively assessed knowledge was associated with fewer false memories but more true memories, suggesting a true discrimination between true and fake news. In contrast, participants who merely believed themselves to be very knowledgeable were more likely to report a memory for true stories, but showed no reduction in false memories. Similarly, individuals who reported high levels of media engagement or anxiety about COVID-19 reported an increase in true (but not false) memories. Finally, higher levels of analytical reasoning were associated with fewer memories for both true and fabricated stories, suggesting a stricter threshold for reporting a memory for any story. These data indicate that false memories can form in response to fake COVID-19 news and that susceptibility to this misinformation is affected by the individual's knowledge about and interaction with COVID-19 information, as well as their tendency to think critically.