Retrieval-Enhanced Suggestibility: A Retrospective and a New Investigation

Guessing as a learning intervention: A meta-analytic review of the prequestion effect

Giving students test questions before they have learned the correct answers (i.e., prequestions) enhances learning. However, existing research has provided conflicting evidence on whether the benefits of prequestions are specific to the initially tested material or if they generalize to new, nontested material. In this review, we summarize the literature on the prequestion effect, describe the attention-based account underlying this effect, report a meta-analysis of the magnitude of the specific and general effects, and explore theoretically and empirically relevant moderator variables that influence the size and direction of the prequestion effect. This preregistered meta-analysis demonstrated a moderate specific effect (g = 0.54, k = 97) but a virtually nonexistent general effect (g = 0.04, k = 91). Overall, the attention-based account received support from some theoretically relevant moderator analyses. Future researchers are encouraged to conduct theoretically motivated studies to help clarify the mechanisms that underlie the attention-enhancing effects of prequestions and to explore the benefits of prequestions in educational domains to establish the extent to which these effects translate into the classroom.

Intrinsic functional connectivity in medial temporal lobe networks is associated with susceptibility to misinformation

Memory is notoriously fallible and susceptible to misinformation. Yet little is known about the underlying cognitive and neural mechanisms that render individuals vulnerable to this type of false memory. The current experiments take an individual differences approach to examine whether susceptibility to misinformation reflects stable underlying factors related to memory retrieval. In Study 1, we report for the first time the existence of substantial individual variability in susceptibility to misinformation in the context of repeated memory retrieval, when the misinformation effect is most pronounced. This variability was not related to an individual's tendency to adopt an episodic retrieval style during remembering (trait mnemonics). In Study 2, we next examined whether susceptibility to misinformation is related to intrinsic functional connectivity in medial temporal lobe (MTL) networks known to coordinate memory reactivation during event retrieval. Stronger resting-state functional connectivity between the MTL and cortical areas associated with visual memory reactivation (occipital cortex) was associated with better protection from misinformation. Together, these results reveal that while memory distortion is a universal property of our reconstructive memory system, susceptibility to misinformation varies at the individual level and may depend on one's ability to reactivate visual details during memory retrieval.

Memory accuracy, suggestibility and credibility in investigative interviews with native and non-native eyewitnesses

Legal practitioners sometimes obtain eyewitness testimonies from non-native language speakers, yet few studies examine the effects of language in investigative interviews. Here, we investigate how testifying in a non-native vs. native language affects memory accuracy, susceptibility to suggestions, and witnesses perceived credibility. After viewing a mock-crime film, participants in Study 1 (N = 121) testified through (1) free recall, (2) cued recall and (3) the Gudjonsson Suggestibility Scales adapted to the crime scenario used in the present study either in their native (Swedish) or a non-native (English) language. They also rated their confidence in their memories, self-perceived credibility and cognitive effort. Native and non-native witnesses did not differ in memory accuracy, susceptibility to suggestions, self-rated credibility or cognitive effort. Non-native (vs. native) speakers did however report lower confidence in their memories. In Study 2, another group of participants (N = 202) were presented with the testimonies from Study 1, and judged witnesses’ credibility. Non-native witnesses were judged as less credible than native speakers. Thus, while the lower confidence exhibited by non-native eyewitnesses did not correspond to their actual memory accuracy, it influenced observers’ judgments of their performance. The results provide important knowledge for legal practices when evaluating the reliability of testimonies from non-native vs. native speaking eyewitnesses.

Experimental and meta-analytic evidence that source variability of misinformation does not increase eyewitness suggestibility independently of repetition of misinformation

Considerable evidence has shown that repeating the same misinformation increases its influence (i.e., repetition effects). However, very little research has examined whether having multiple witnesses present misinformation relative to one witness (i.e., source variability) increases the influence of misinformation. In two experiments, we orthogonally manipulated repetition and source variability. Experiment 1 used written interview transcripts to deliver misinformation and showed that repetition increased eyewitness suggestibility, but source variability did not. In Experiment 2, we increased source saliency by delivering the misinformation to participants via videos instead of written interviews, such that each witness was visibly and audibly distinct. Despite this stronger manipulation, there was no effect of source variability in Experiment 2. In addition, we reported a meta-analysis (k = 19) for the repeated misinformation effect and a small-scale meta-analysis (k = 8) for the source variability effect. Results from these meta-analyses were consistent with the results of our individual experiments. Altogether, our results suggest that participants respond based on retrieval fluency rather than source-specifying information.

Interpolated retrieval retroactively increases recall and promotes cross-episode memory interdependence

Retrieving existing memories before new learning can lead to retroactive facilitation. Three experiments examined whether interpolated retrieval is associated with retroactive facilitation and memory interdependence that reflects integrative encoding. Participants studied two lists of cue-response word pairs that repeated across lists (A-B, A-B), appeared in list 1 (A-B, -), or included the same cues with changed responses in each list (A-B, A-C). For A-B, A-C pairs, the tasks interpolated between lists required recall of list 1 (B) responses (with or without feedback) or restudy of complete list 1 (A-B) pairs. In list 2, participants only studied pairs (experiment 1) or studied pairs, attempted to detect changed (C) responses, and attempted to recall list 1 responses for detected changes (experiments 2 and 3). On a final cued recall test, participants attempted to recall list 1 responses, indicated whether responses changed between lists, and if so, attempted to recall list 2 responses. Interpolated retrieval was associated with subsequent retroactive facilitation and greater memory interdependence for B and C responses. These correlational findings are compatible with the view that retrieval retroactively facilitates memories, promotes coactivation of existing memories and new learning, and enables integrative encoding that veridically binds information across episodes.

If you express it in the form of a negation, you can expect an effect similar to misinformation

The primary goal of the presented research was to investigate how processing post-event information affects memory of details in an event viewed on video. We used two forms of post-event information: classic misinformation (changing or implanting new information into memory) and a new form that involves a correct explicit or implicit negation of the existence of an object in the video. We followed the three-step procedure used in studies on the misinformation effect, with a final memory test that was either immediate or delayed by a week and consisted in indicating which objects appeared in the video. We replicated the misinformation effect. More importantly, in the delayed test condition, both explicitly and implicitly negated objects were falsely recalled more often than unmentioned objects. These results indicate that it is possible to induce negation-related false memories; they also show that memory is impaired by negated post-event information or misleading post-event information.

Imagined places of the past: the interplay of time and memory in the maintenance of place attachment

Place attachment describes the emotional connection that people hold with a physical space, and such bonds have been shown to be associated with higher levels of life satisfaction, as well as physical and mental well-being. Although a temporal element of place attachment is acknowledged, the exact nature of time’s role in such relationships is yet to be fully understood. The current study addressed this using qualitative interviews with nine long-term residents of an urban centre in Northwest England. Interpretative phenomenological analysis was applied to explore the underlying mechanisms through which time asserts its influence on place attachment. Analysis developed three interrelated super-ordinate themes: what time brings, accumulated attachment, and time as a dialectic. As time passes, life events, cultural changes, and physical transformation to the environment affect individuals’ interactions with place, and thus their relationship with it. Continued inhabitation leads to an accumulation of emotional salience. Ultimately, time interacts with human memory, offering individuals multiple perspectives through which to make sense of their present environment. Issues may then arise, as memory is heavily influenced by the passing of time. Consequently, present-day perceptions of the place’s past are often viewed through a prism of nostalgia, with implications for the person-place bond.

Social Influence and Autobiographical Recall: Shared Reality and Epistemic Trust Shape Perceptions of Autobiographical Events

Two experiments studied the evaluative adaptation process at the outset of a communication event to examine how autobiographical memory could be shaped by audience attitude, shared reality, and epistemic trust. Experiment 1 found that audience attitude influenced communicator perceptions of their own autobiographical memories and attitudes toward the memory topic. These effects were more pronounced when communicators experienced a shared reality with their audience. Experiment 2 found that epistemic trust in the audience increased shared reality with the audience, which in turn led to greater audience-congruent memory bias in which communicators had memory perceptions and attitudes that were evaluatively consistent with the attitudes of their audience. This project underscores the prevalence of social influence processes in autobiographical recall and identifies how processes that occur at the initial stages of interpersonal communication (i.e., perceived audience attitude, trust, and shared reality) can influence how individuals construe their own life events.

Are witnesses able to avoid highly accessible misinformation? Examining the efficacy of different warnings for high and low accessibility postevent misinformation

The reliability of eyewitness memory continues to be an area of concern, particularly in situations that involve conflicting sources of information (e.g., the misinformation effect; Loftus et al., 1978, Journal of Experimental Psychology: Human Learning and Memory, 4[1], 19-31). To mitigate the negative effects of misinformation, researchers have examined the efficacy of warnings that highlight the unreliability of postevent information. However, warnings have proven less effective for highly accessible misinformation (Eakin et al., 2003, Journal of Experimental Psychology: Learning, Memory, and Cognition, 29[5], 813-825). In the present study, we examined the effects of different types of warnings for low accessibility misinformation in a standard single test misinformation paradigm, and highly accessible misinformation in a repeated testing misinformation paradigm (Chan et al., 2009, Psychological Science, 20[1], 66-73). We modeled these warnings after Eakin et al. (2003) to include both general warnings and specific question-by-question warnings. We found that warnings were effective in both types of misinformation paradigms. Additionally, memory accuracy in situations where participants were exposed to misleading information was improved when specific and general warnings were combined. We argue that both retrieval blocking of low accessibility items and enhanced contextual discrimination account for these findings.

Does testing enhance new learning because it insulates against proactive interference?

Taking a test on previously learned material can enhance new learning. One explanation for this forward testing effect is that retrieval inoculates learners from proactive interference (PI). Although this release-from-PI account has received considerable empirical support, most extant evidence is correlational rather than causal. We tested this account by manipulating the level of PI that participants experience as they studied several lists while receiving interpolated tests or not. In Experiments 1 and 2, we found that testing benefited new learning similarly regardless of PI level. These results contradict those from Nunes and Weinstein (Memory, 20(2), 138-154, 2012), who found no forward testing effect when encoding conditions minimized PI. In Experiments 3 and 4, we failed to replicate their results. Together, our data indicate that reduced PI might be a byproduct, rather than a causal factor, of the forward testing effect.

Memory updating after retrieval: when new information is false or correct

We conducted three experiments testing the malleability of memory in incorporating new information following retrieval. All experiments used associative lists typical of the DRM paradigm [Deese, J. (1959). On the prediction of occurrence of particular verbal intrusions in immediate recall. Journal of Experimental Psychology, 58(1), 17-22; Roediger, H. L., & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21(4), 803-814]. This paradigm enabled the evaluation of the integration of false information and correct information with the original information. In Experiment 1, participants studied DRM lists, and in a later phase either retrieved or restudied the lists and were presented with never-presented critical lures. The results of Experiment 1 showed that compared to restudy, retrieval enhanced the integration of subsequent false information, as measured by later recall in a follow-up test. In Experiments 2 and 3, after initial study, participants retrieved or studied incorrect information and received corrective feedback. The results showed that retrieval led to more error correction than restudy, when feedback was presented immediately. In general, this research suggests retrieval facilitates incorporation of new, related information, regardless of whether it is false or correct.

Effects on Memory of Early Testing and Accuracy Assessment for Central and Contextual Content

Memory for an event is influenced by many factors including retention interval, frequency of assessment, and type of information assessed concerning the event. We examined the usefulness of observer memory for contextual information in assessing accuracy of memory for central information. Participants viewed a video of a purse being stolen and were asked questions concerning the perpetrator and surrounding context of the event, including where and when the event occurred and who else was present. Participants tested immediately after seeing the video exhibited better memory than those tested for the first time 48-hour after the event. Additionally, testing immediately after viewing the video reduced forgetting over the 48-hour delay (i.e., early testing attenuated subsequent forgetting). Moreover, memory for the context of the event correlated positively with memory of the central information (i.e., perpetrator), and memory concerning other people at the event tended to have the highest correlation with perpetrator memory.

Protective effects of testing across misinformation formats in the household scene paradigm

Many studies have demonstrated retrieval-enhanced suggestibility (RES), in which taking an initial recall test after witnessing an event increases suggestibility to subsequent misinformation introduced via a narrative. Recently, however, initial testing has been found to have a protective effect against misinformation introduced via cued-recall questions. We examined whether misinformation format (narrative vs. cued-recall questions) yields a similar dissociation in a paradigm that, to date, has consistently yielded a protective effect of testing (PET). After studying photos of household scenes (e.g., kitchen), some participants took an initial recall test. After a 48-hr delay, items not presented in the scenes (e.g., knives/plates) were suggested either via narrative or questions. Regardless of the misinformation format, we found a PET on both initial-test-conditionalised free recall and source-monitoring tests. However, initial testing also yielded memory costs, such that suggested items reported on the initial test were likely to persist on a final recall test. Thus, initial testing can protect against suggestibility, but can also precipitate memory errors when intrusions emerge on an initial test.

The feature boost in false memory: the roles of monitoring and critical item identifiability

The feature boost refers to increased false memories for word lists that are both associatively and categorically (C + A) related to a non-presented critical item (CI) relative to lists that are only associatively (NC-A) related [Coane, J. H., McBride, D. M., Termonen, M.-L., & Cutting, J. C. (2016). Categorical and associative relations increase false memory relative to purely associative relations. Memory & Cognition, 44(1), 37-49. doi:10.3758/s13421-015-0543-1]. We explored the replicability of the feature boost and its dependance on monitoring processes by explicitly warning participants about the nature of the lists or by asking participants to guess the CI (implicit warning). Overall, the feature boost was replicated. Guessing performance was higher for C + A lists than for NC-A lists. Explicit warnings were equally effective for both list types in reducing false memory relative to recall and to a no-recall math condition. When the CI was not guessed or recalled, the feature boost emerged. However, when the CI was guessed or previously recalled, false alarms did not differ as a function of list type. The feature boost seems to be driven in part by differences in the identifiability of the CI, such that CIs related to C + A lists are harder to identify and thus reject. These results suggest that differences in monitoring processes that are sensitive to CI identifiability contribute to the effect.

Telling a good story: The effects of memory retrieval and context processing on eyewitness suggestibility

Witnesses are likely to describe a crime many times before testifying or encountering misinformation about that crime. Research examining the effect of retrieval on later suggestibility has yielded mixed results. LaPaglia and Chan manipulated whether misinformation was presented in a narrative or misleading questions, and they found that retrieval increased suggestibility when misinformation was presented in a narrative, but reduced suggestibility when the same misinformation was presented in questions. In the current study, we aimed to address why these differences occurred. Specifically, we examined whether contextual detail and narrative coherence during misinformation exposure influenced the relation between retrieval and suggestibility. Participants watched a robbery video and some were questioned about the event afterwards. They were then exposed to misinformation presented in a narrative (Experiment 1) or questions (Experiment 2) before taking a final memory test. Testing enhanced suggestibility when the misinformation phase reinstated contextual information of the event, but not when the misinformation phase included few contextual details–regardless of whether the misinformation was in a narrative or questions. In Experiment 3, disrupting narrative coherence by randomizing the order of contextual information eliminated retrieval-enhanced suggestibility. Therefore, context processing during the post-event information phase influences whether retrieval enhances or reduces eyewitness suggestibility.