Postevent Narrative Research Articles

How prior testing impacts misinformation processing: A dual-task approach.

Research suggests that testing prior to the presentation of misinformation influences how that misinformation is processed. The present study examined the relationship between testing, the demands of misinformation narrative processing, and memory for original and post-event information. Using response latencies to a secondary task, we tested whether prior testing influenced the available resources for secondary task processing. Additionally, we investigated whether changes in narrative processing were specific to critical details tested earlier. Participants engaged in an eyewitness memory paradigm in which half were tested prior to receiving the post-event narrative. Participants responded to the secondary task at specified time points during the narrative. All participants took a final memory test after listening to the post-event narrative. We found that testing interacted with the placement of the secondary task. When responding on the secondary task was closely linked to the presentation of previously tested critical details in the narrative, retrieval-enhanced suggestibility was reduced on tests of event memory (Experiment 1) and increased post-event information learning was revealed on tests of narrative memory (Experiment 2).

An experimental examination of the effects of alcohol consumption and exposure to misleading postevent information on remembering a hypothetical rape scenario.

SummaryWe experimentally examined the effects of alcohol consumption and exposure to misleading postevent information on memory for a hypothetical interactive rape scenario. We used a 2 beverage (alcohol vs. tonic water) × 2 expectancy (told alcohol vs. told tonic) factorial design. Participants (N = 80) were randomly assigned to conditions. They consumed alcohol (mean blood alcohol content = 0.06%) or tonic water before engaging in the scenario. Alcohol expectancy was controlled by telling participants they were consuming alcohol or tonic water alone, irrespective of the actual beverage they were consuming. Approximately a week later, participants were exposed to a misleading postevent narrative and then recalled the scenario and took a recognition test. Participants who were told that they had consumed alcohol rather than tonic reported fewer correct details, but they were no more likely to report incorrect or misleading information. The confidence–accuracy relationship for control and misled items was similar across groups, and there was some evidence that metacognitive discrimination was better for participants who were told that they had consumed alcohol compared with those told they had tonic water. Implications for interviewing rape victims are discussed.

Bilingual witnesses are more susceptible to the misinformation effect in their less proficient language

The misinformation effect occurs when a witness views an event, is exposed to misleading post-event information, and remembers some misleading details as having occurred in the original event. The present study examined the effect of receiving post-event information and being tested in different languages on bilingual participants’ susceptibility to the misinformation effect. English-Spanish bilingual participants (N = 234; 78% claimed English was their dominant language) watched a video, read a post-event narrative in English or in Spanish, and then were tested on details of the video in English or in Spanish. Regardless of the language in which participants read the post-event narrative, participants who were tested in English correctly recognized more true details and falsely recognized fewer misinformation details than those tested in Spanish. These results suggest that bilingual participants are more susceptible to the misinformation effect in their less proficient language, a finding that has important implications for interviewing bilingual witnesses. Even when witnesses claim to be fluent in two languages, testing their memory in their less fluent language may result in fewer true memories and more false memories.

Discrepancy detection in the retrieval-enhanced suggestibility paradigm

ABSTRACTRetrieval-enhanced suggestibility (RES) refers to the finding that immediately recalling the details of a witnessed event can increase susceptibility to later misinformation. In three experiments, we sought to gain a deeper understanding of the role that retrieval plays in the RES paradigm. Consistent with past research, initial testing did increase susceptibility to misinformation – but only for those who failed to detect discrepancies between the original event and the post-event misinformation. In all three experiments, subjects who retrospectively detected discrepancies in the post-event narratives were more resistant to misinformation than those who did not. In Experiments 2 and 3, having subjects concurrently assess the consistency of the misinformation narratives negated the RES effect. Interestingly, in Experiments 2 and 3, subjects who had retrieval practice and detected discrepancies were more likely to endorse misinformation than control subjects who detected discrepancies. These results call attention to limiting conditions of the RES effect and highlight the complex relationship between retrieval practice, discrepancy detection, and misinformation endorsement.

Looking for answers in all the wrong places: How testing facilitates learning of misinformation

Abstract Research has consistently demonstrated that taking a test prior to receiving misleading information increases eyewitness suggestibility (Chan, Thomas, & Bulevich, 2009). Retrieval Enhanced Suggestibility (RES) is characterized by two typical findings: (1) reduced access to the originally witnessed event, which has been contextualized within a reconsolidation framework (e.g., Chan & LaPaglia, 2013), and (2) increased production of misleading post-test narrative details, which has been discussed as an example of test-potentiated learning (Gordon & Thomas, 2014). The present study focused on this latter finding, and examined attention as a potential factor moderating the relationship between initial testing and narrative detail production. We hypothesized that initial testing would influence endogenous attention allocation to details in the post-event narrative, thereby impacting narrative learning. We found that compared to participants who did not take an initial test, participants who took an initial test focused efforts on processing narrative details that were directly relevant to initial test questions, and this differential attention allocation was directly related to final test misinformation production. These experiments provide support for the view that testing enhances susceptibility to misinformation by potentiating learning of post-event information. In addition, the present findings support the conclusion that initial test questions and answers function as endogenous cues to direct attention during post-test learning.

Testing potentiates new learning in the misinformation paradigm

Retrieval enhanced suggestibility (RES) is the finding that the misinformation effect is exacerbated when a test precedes misleading postevent information (Chan, Thomas, & Bulevich Psychological Science 20: 66-73, 2009). In the present study, we tested three hypotheses relevant to RES. First, we examined whether retrieval of critical details was necessary for the RES effect. Second, we examined whether initial testing influenced the allocation of attention to critical details during postevent information processing. Finally, we examined whether RES resulted in impaired access to the originally learned information. We compared three groups of participants in three experiments: an identical-test group, a related-test group, and a standard misinformation group. Both testing groups were tested on the original event before the introduction of misinformation; however, the identical-test group took the same test before and after the misinformation, whereas the related-test group took different tests before and after misinformation. We found that testing before misleading postevent information affected attention allocation to details in the postevent narrative. Furthermore, the RES effect did not accompany reduced accessibility to the original information, as measured by a modified-modified free recall test. These data have implications for how testing may potentiate new learning.

Post‐event information presented in a question form eliminates the misinformation effect

This study investigated the influences of sentence surface forms on the misinformation effect. After viewing a film clip, participants received a post-event narrative describing the events in the film. Critical sentences in the post-event narrative, presented in either a statement or a question form, contained misinformation instead of questions with embedded false presuppositions; thus participants did not have to answer questions about the original event. During the final cued-recall test, participants were informed that any relevant information presented in the post-event narrative was not in the original event and that they should not report it. Consistent with previous findings, Experiment 1 demonstrated that post-event information presented as an affirmative statement produced the misinformation effect. More importantly, post-event information presented in a question form, regardless of whether it contained a misleading or studied item, increased the recall of correct information and reduced false recall. Experiment 2 replicated the main finding and ruled out an alternative explanation based on the salience of misleading items. Post-event information presented in a question form created a condition similar to that which produces the testing effect.

Testing promotes eyewitness accuracy with a warning: Implications for retrieval enhanced suggestibility

Numerous studies have demonstrated that repeated retrieval boosts later retention. However, recent research has shown that testing can increase eyewitness susceptibility to misleading post-event information (e.g., Chan, Thomas, & Bulevich, 2009). The present study examines the effects of warning on this counterintuitive finding. In two experiments, subjects either took an initial test or performed a filler task after they viewed a video event. They were then given post-event information before they took a final test. Critically, one group of subjects was warned about potential inaccuracies in the post-event narrative and the other group was not. Without a warning, subjects who received an initial test were more likely to endorse misleading post-event information, replicating the retrieval-enhanced suggestibility (RES) effect. However, this RES effect was eliminated when subjects were warned about the veracity of the narrative. These results are consistent with a retrieval fluency account of RES.

Psychotropic placebos reduce the misinformation effect by increasing monitoring at test

A psychotropic placebo can help people resist the misinformation effect, an effect thought to be caused by a shift to more stringent source monitoring. When this shift occurs has been unclear. To address this issue we gave some people—but not others—a phoney cognitive-enhancing drug we called R273. Shortly afterwards, everyone took part in a misinformation effect experiment. To gather evidence about source monitoring we surreptitiously recorded time to read the misleading postevent narrative, and response time at test. Our findings suggest that people shifted to more stringent source monitoring at test. Moreover, people with higher working memory capacity (WMC) performed better than people with lower WMC—but only when they were told they had received R273, a finding that fits with research showing that WMC can confer advantages in situations demanding effortful control, but not when automatic heuristics suffice.

Tainted Truth: Overcorrection for Misinformation Influence on Eyewitness Memory

Existing research shows that the postevent misinformation effect on eyewitness memory can be successfully reduced by retrospective warnings. Exploring potential costs of such warnings, we investigated whether warned eyewitnesses might overcorrect for misinformation influence from the postevent source. Across three experiments, warned participants recognized relatively fewer event items that were truthfully described in a postevent narrative (“tainted” event items) than did unwarned participants. This tainted truth effect was obtained for peripheral but not for central event items (Experiments 1–3); it persisted when the warning took the form of an explicit source–monitoring instruction (Experiment 2) and when the accessibility of the postevent information was increased (Experiment 3). Overall, the effect was stronger with a socially framed warning than with more direct, explicitly phrased warnings. The findings suggest that the tainted truth effect is due to more careful monitoring for information from a suspicious postevent source rather than mere memory impairment.

The cognitive interview and its effect on misleading postevent information

The present study investigated the effectiveness of the cognitive interview on reducing the impact of the misinformation effect. A 2×2 between-groups design was used, with interview type (cognitive or structured) and narrative type (misleading or neutral) as the independent variables. Adults (n=40) viewed video footage depicting a bank robbery and then received either a misleading or neutral postevent narrative. Participants were interviewed with either a cognitive or a structured interview regarding their memory for the original footage. The cognitive interview produced significantly more correct pieces of information than the structured interview, without an increase in errors or confabulations. An anomalous significant interaction was found regarding the number of incorrect pieces of information, where recipients of the structured interview made more recall errors when receiving neutral postevent information compared to neutral postevent information. A misinformation effect was successfully achieved but the enhancing effects of the cognitive interview were unable to reduce it. Results are discussed within the misinformation effect theoretical framework. The limitations of the present study are also discussed.

Pre-event stereotypes and misinformation effects in young children

This study examined the effects of pre-event stereotypes on 5-year-old children's memories for the visit of an adult male to their school. Children were read three stories in which this man was described in positive, negative, or neutral terms. Following the visit, children were read post-event narratives which contained positive and negative misinformation that was consistent and inconsistent with the pre-event stereotype. Children were then given a recognition test under inclusion and exclusion instructions. Negative misinformation was correctly rejected more often than positive misinformation. Children given a positive pre-event stereotype were more likely to accept positive misinformation than those in the other stereotype conditions. Process dissociation analyses revealed that recollection for negative misinformation was larger than for positive misinformation; the opposite was the case for familiarity.

The power of the spoken word: Sociolinguistic cues influence the misinformation effect

We investigated whether the sociolinguistic information delivered by spoken, accented postevent narratives would influence the misinformation effect. New Zealand subjects listened to misleading postevent information spoken in either a New Zealand (NZ) or North American (NA) accent. Consistent with earlier research, we found that NA accents were seen as more powerful and more socially attractive. We found that accents per se had no influence on the misinformation effect but sociolinguistic factors did: both power and social attractiveness affected subjects' susceptibility to misleading postevent suggestions. When subjects rated the speaker highly on power, social attractiveness did not matter; they were equally misled. However, when subjects rated the speaker low on power, social attractiveness did matter: subjects who rated the speaker high on social attractiveness were more misled than subjects who rated it lower. There were similar effects for confidence. These results have implications for our understanding of social influences on the misinformation effect.

Amalgamations of memories: intrusion of information from one event into reports of another

SUMMARY Numerous researchers have reported that exposure to misleading postevent information (MPI) regarding details in a witnessed event can lead people to report false details from the MPI when asked to report the witnessed event. In such studies, the MPI is presented to participants in the context of information about the witnessed event. This experiment tests the hypothesis that postevent exposure to information that participants know is not about the witnessed event can, nonetheless, aAect performance on tests of memory for that event. As predicted, when asked to report details of an event depicted in a slide show, participants tended to intrude details mentioned in a recent postevent narrative that described a diAerent event. #1998 John Wiley & Sons, Ltd.

Cross-language postevent misinformation effects in Spanish–English bilingual witnesses.

Three experiments examined whether postevent misinformation affects eyewitness memory across languages in bilingual witnesses. Participants watched a videotaped simulation of a robbery, read a postevent narrative that contained misleading information about the robbery, and answered either forced-choice or cued-recall questions about 6 target items from the videotape. Experiment 1 was conducted entirely in English, but Experiments 2 and 3 tested Spanish-English bilingual participants who were exposed to 1 of 3 language combinations of the postevent narrative and memory test-Spanish-Spanish, English-Spanish, or Spanish-English (as well as English-English in Experiment 3). Across all 3 experiments, the effects of postevent misinformation were as large in the cross-language conditions as in the same-language conditions. This study has important implications for the justice system, and the results suggest new ways to study postevent misinformation effects and bilingual memory.

The Effect of Memory Trace Strength on Suggestibility

This experiment tests the memory trace strength theory of suggestibility, that stronger memories are more resistant to suggestibility than weaker memories, with strength of memory manipulated by means of frequency of presentation of target items. Four- and 10-year-old children viewed a slide sequence in which four target slides were presented one or two times each. In a postevent narrative, participants were misled about two target items, and two target items served as controls. In a subsequent recognition memory test, the hypothesis was confirmed. The d′ difference between control and misled items was greater for frequency one than for frequency two; stronger memories (items viewed twice) were more resistant to suggestibility than weaker memories (items viewed once). This pattern was consistent for both 4- and 10-year-old children, indicating that similar cognitive processes underlie suggestibility at each age. These results suggest that if children′s memory is tested for an event that occurred to them frequently, they would be expected to have more accurate memory for this event and be less vulnerable to suggestive influences such as biased interviewing procedures than they would for an event that occurred only a single time.

Memory impairment and source misattribution in postevent misinformation experiments with short retention intervals.

The four experiments reported here provide evidence that (1) misleading postevent suggestions can impair memory for details in a witnessed event and (2) subjects sometimes remember suggested details as things seen in the event itself. All four experiments used recall tests in which subjects were warned of the possibility that the postevent information included misleading suggestions and were instructed to report both what they witnessed in the event and what was mentioned in the postevent narrative. Recall of event details was poorer on misled items than on control items, and subjects sometimes misidentified the sources of their recollections. Our results suggest that these findings are not due to guessing or response biases, but rather reflect genuine memory impairment and source monitoring confusions.

Discrepancy detection and vulnerability to misleading postevent information.

When people are exposed to misleading details after a witnessed event, they often claim that they saw the misleading details as part of the event. We refer to this as themisinformation effect. In four experiments, involving 570 subjects, we explored the role that discrepancy detection plays in the misinformation effect. Experiment 1 showed that subjects who naturally read a post-event narrative more slowly were more resistant to the effects of misleading information contained in the narrative. In Experiment 2, subjects who naturally read more slowly were more likely to detect a discrepancy between what they were reading and what was stored in their memory. In Experiment 3, subjects who were instructed to read slowly were more likely to detect a discrepancy than were those who were instructed to read quickly. In Experiment 4, subjects who were instructed to read slowly were more resistant to misleading postevent information. Taken together, these results suggest that longer reading times are associated with a greater scrutiny of postevent information. This leads to an increased likelihood that discrepancies will be detected and that the misinformation will be resisted.