How schemas affect eyewitness memory over repeated retrieval attempts

After observing a crime eyewitnesses are typically interviewed many times over an extended period of time. We examined how schema for a crime influenced the types of information eyewitnesses remembered and forgot across multiple interviews. People's schema for a bank robbery were identified, and recall of schema‐consistent, schema‐inconsistent and schema‐irrelevant information was extracted from eyewitness interviews conducted in two experiments which manipulated retention interval (3 days–12 weeks) and number of interviews (2–4). Consistent with fuzzy‐trace and associative network theories, schemas preserved accuracy for information central to the crime (schema‐consistent and inconsistent) at the expense of schema‐irrelevant information. Schema‐consistent intrusions did not increase across interviews. Copyright © 2003 John Wiley & Sons, Ltd.     

The influence of alcohol and weapon presence on eyewitness memory and confidence

In this quasi-experimental field study, bar drinkers (0.00–0.23% blood alcohol content) viewed a photographic sequence in which a male took a laptop from a helpdesk assistant, either on loan or at gunpoint. Following a brief retention period, participants answered 20 multiple-choice questions about the male, his actions, and details of the scene, then attempted to identify him from a simultaneous target-present or target-absent line-up. Alcohol was associated with a reduction in correct identifications and an increase in false identifications. Surprisingly, the presence of a weapon in the scene enhanced identification accuracy, though wider scene memory was not influenced by alcohol or the weapon. Findings offer some support for the view that alcohol restricts face encoding, perhaps through the narrowing of attention to salient external features (e.g., hair). We also suggest that curiosity about mock-crime perpetrators may produce weapon focus reversals, although the factors that might elicit such curiosity remain unclear.     

Short-term memory loss over time without retroactive stimulus interference

A key question in cognitive psychology is whether information in short-term memory is lost as a function of time. Lewandowsky, Duncan, and Brown (2004) argued against that memory loss because forgetting in serial recall occurred to the same extent across serial positions regardless of the rate of recall. However, we believe Lewandowsky et al. (2004) only prevented one of two types of rehearsal; they did not prevent nonarticulatory rehearsal via attention. To prevent articulatory and nonarticulatory rehearsal without introducing interference, we presented unevenly timed stimuli for serial recall and, on some trials, required that the timing of stimuli be reproduced in the response. In those trials only, evidence of memory loss over time emerged. Further research is needed to identify whether this memory loss is decay or lost distinctiveness.     

Undoing suggestive influence on memory: The reversibility of the eyewitness misinformation effect

Presenting inconsistent postevent information about a witnessed incident typically decreases the accuracy of memory reports concerning that event (the misinformation effect). Surprisingly, the reversibility of the effect (after an initial occurrence) has remained largely unexplored. Based on a memory conversion theoretical framework and associated refined assessment strategy, we report three experiments to demonstrate that suggestive influence can be completely undone. Initially established misinformation effects were eliminated - even after a period of 5weeks (Exp. 3) - through (a) an enlightenment procedure ensuring an adequate representation of the memory task as a search for potentially two contradictory items (instead of "the" single "correct" answer) and (b) using a memory state test that unconfounds the performance contributions of item and source memory by assessing them separately. Specifically, memory for original event details that were the target of misinformation was restored to the level of non-misled control performance, and even beyond (Exp. 3). This remarkable reversibility of misinformation influence highlights the central role of memory conversion processes in the misinformation effect (but does not principally exclude the contribution of traditional interference processes). We discuss the compatibility of our findings with previous research and make suggestions for real-world eyewitness interrogation.     

Worry and working memory influence each other iteratively over time

Little research has examined whether the relationship between working memory (WM) and anxiety/worry remains stable or changes over time; and, if changes occur, the factor(s) influencing change. Claims about influence are typically inferred from data collected at a single time point, and may misrepresent the nature of influence. To investigate the iterative influence of WM and Worry and/or vice versa, 133 fourteen-year-olds completed WM and Worry measures several times over the course of a single day as they prepared for a math test. We used a bivariate latent difference score model to analyse possible changes in WM–Worry relationships. The best fitting model indicated high Worry predicts decreases in WM, and low or decreased WM predicts increases in Worry; high WM with low Worry predicts accurate problem solving; low WM with high Worry predicts inaccurate problem solving. Findings show relationships between WM and Worry varies considerably over a single day, and initial disadvantages become worse over time.     

The influence of the lexicon on phonetic categorization: stimulus quality in word-final ambiguity.

The categorization of word-final phonemes provides a test to distinguish between an interactive and an autonomous model of speech recognition. Word-final lexical effects ought to be stronger than word-initial lexical effects, and the models make different reaction time (RT) predictions only for word-final decisions. A first experiment found no lexical shifts between the categorization functions of word-final fricatives in pairs such as fish-fiss and kish-kiss. In a second experiment, with stimuli degraded by low-pass filtering, reliable lexical shifts did emerge. Both models need revision to account for this stimulus-quality effect. Stimulus quality rather than stimulus ambiguity per se determines the extent of lexical involvement in phonetic categorization. Furthermore, the lexical shifts were limited to fast RT ranges, contrary to the interactive model's predictions. These data therefore favor an autonomous bottom-up model of speech recognition.     

Reliance on schemas in source memory: age differences and similarity of schemas

The present study has examined the effects of source-schema-consistency, schematic distinctiveness and encoding time of schematic information on source memory of younger and older adults. Participants were administered a source memory test, in which two sources presented statements that were congruent with, incongruent with or irrelevant to sources' professions. Professions of sources were schematically similar or distinct, and they were revealed before or after the presentation of items. The results yielded that revelation of profession information before presentation of items enhanced source memory for incongruent items. Aging was associated with a general decrease in source monitoring processes. Participants who were assigned to similar-source condition and had their schemas activated before learning phase had higher source monitoring scores. Results are discussed in relation to source monitoring framework and aging of memory.     

The eyewitness suggestibility effect and memory for source

We examined the possibility that eyewitness suggestibility reflects failures of the processes by which people normally discriminate between memories derived from different sources. To test this hypothesis, misled and control subjects were tested either with a yes/no recognition test or with a "source monitoring" test designed to orient subjects to attend to information about the sources of their memories. The results demonstrate that suggestibility effects obtained with a recognition test can be eliminated by orienting subjects toward thinking about the sources of their memories while taking the test. Our findings indicate that although misled subjects are capable of identifying the source of their memories of misleading suggestions, they nonetheless sometimes misidentify them as memories derived from the original event. The extent to which such errors reflect genuine memory confusions (produced, for example, by lax judgment criteria) or conscious misattributions (perhaps due to demand characteristics) remains to be specified.     

Creating shared reality about ambiguous sexual harassment: The role of stimulus ambiguity in audience-tuning effects on memory

By tuning messages about ambiguous information to their audience's attitude, communicators can reduce uncertainty and form audience-congruent memories. This effect has been conceptualized as the creation of shared reality with the audience. We applied this approach to representations of ambiguous antecedents of sexual harassment and examined whether the effect depends on the event's perceived ambiguity. Participants read a testimony about a supervisor's ambiguous behaviors toward a female employee and described the behaviors to an audience who had previously evaluated him positively or negatively. We manipulated perceived ambiguity of the testimony by including or omitting information about eventual, clear-cut harassment (known vs. unknown outcome). As predicted, participants aligned their messages and memory with their audience's evaluation only in the unknown-outcome condition, where epistemic uncertainty was higher. The findings highlight the role of epistemic needs in the communicative creation of a shared reality about a ubiquitous social situation with potentially harmful outcomes.     

Some effects of alcohol on eyewitness memory

Male volunteers (N = 120) in small groups of 5 to 10 watched a staged theft involving live actors. Some (n = 47) were under the influence of alcohol (average blood alcohol level of .10) at the time. Some subjects (n = 58) were interviewed immediately after the event, and all were interviewed 1 week later. The delayed interview included the presentation of a photospread that either did or did not contain the picture of the "thief." Alcohol suppressed the amount recalled during the immediate interview and both the amount and accuracy of recall after the 1-week delay. Alcohol had no influence on the ability of witnesses to recognize the thief's picture. When the thief's picture was not present in the photospread, however, alcohol increased the rate of false identifications. An immediate interview substantially improved the amount of information subjects were able to recall 1 week later.     

Reinstating salience effects over time: the influence of stimulus changes on visual selection behavior over a sequence of eye movements

Recently, we showed that salience affects initial saccades only in a static stimulus environment; subsequent saccades were unaffected by salience but, instead, were directed in line with task requirements (Siebold, van Zoest, & Donk, PLoS ONE 6(9): e23552, 2011). Yet multiple studies have shown that people tend to fixate salient regions more often than nonsalient ones when they are looking at images—in particular, when salience is defined by dynamic changes. The goal of the present study was to investigate how oculomotor selection beyond an initial saccade is affected by salience as derived from changing, as opposed to static, stimuli. Observers were presented with displays containing two fixation dots, one target, one distractor, and multiple background elements. They were instructed to fixate on one of the fixation dots and make a speeded eye movement to the target, either directly or preceded by an initial eye movement to the other fixation dot. In Experiment 1, target and distractor differed in orientation contrast relative to the background, such that one was more salient than the other, whereas in Experiments 2 and 3, the orientation contrast between the two elements was identical. Here, salience was implemented by a continuous luminance flicker or by a difference in luminance contrast, respectively, which was presented either simultaneously with display onset or contingent upon the first saccade. The results showed that in all experiments, initial saccades were strongly guided by salience, whereas second saccades were consistently goal directed if the salience manipulation was present from display onset. However, if the flicker or luminance contrast was presented contingent upon the initial saccade, salience effects were reinstated. We argue that salience effects are short-lived but can be reinstated if new information is presented, even when this occurs during an eye movement.     

The impact of misleading questions on eyewitness memory in children and adults

The study examined developmental patterns of the negative effect of misleading post‐event information in two different kinds of eyewitness interviews. A total of 284 subjects aged between five and 64 years were shown a short video about a theft and three weeks as well as four weeks later questioned about it. The social pressure in the interview after three weeks was manipulated by asking half of the subjects suggestive and misleading questions. The other half was asked open‐ended and unbiased questions. In the neutral interview four weeks later, all subjects were asked the same set of recognition questions about the event. The results revealed that preschoolers in particular had problems with the interplay between cognitive and social factors (social pressure induced through the wording of the misleading questions) in the interview setting after three weeks. In the neutral recognition test, all age groups were shown to suffer from prior misinformation to about the same extent. However, with an exception in the group of 6‐year‐old children the negative effect of prior misinformation on the accuracy of recognition proved to be due to items that were peripheral to the observed event. Copyright © 2000 John Wiley & Sons, Ltd.     

The effects of varied retrieval cues on reminiscence in eyewitness memory

Eyewitnesses sometimes recall things at later interviews that they did not recall at previous interviews (reminiscence). When these cases are argued in the courtroom, attorneys may claim (and judges may warn jurors) that eyewitnesses who provide reminiscences are necessarily inaccurate witnesses. Consequently, their testimony may be prematurely discredited or dismissed. We examined here the role of varying the retrieval cues across interviews to account for reminiscence. Participants watched a videotaped mock crime and were tested for recall on two occasions using the same or different cues. Results supported the hypothesis that varying retrieval cues increases the amount of reminiscence. Furthermore, nearly all participants exhibited some reminiscence. Finally, reminiscence was not significantly correlated with overall accuracy of testimony. These findings suggest that many of the assumptions underlying legal tactics and judges' instructions regarding reminiscent inconsistencies are erroneous. Copyright © 2006 John Wiley & Sons, Ltd.     

The role of stimulus ambiguity and movement in spatial navigation: a multiple memory systems analysis of location discrimination

This paper reviews recent findings about how rats navigate by learning to discriminate among locations. The assumption underlying the experiments and their interpretation is that the information required to do this is learned by three independent, parallel memory systems. One system processes cognitive information (or "knowledge"), a second system processes reinforced stimulus-response associations and a third processes Pavlovian conditioned responses in the form of stimulus-affect associations. The information stored in each system produces behavior that, in some cases, results in a location discrimination. The present experiments focus on three factors that influence what each system learns and whether the resulting memory produces behavior that results in a location discrimination. One factor is whether the locations to be discriminated can be identified by unique, unambiguous stimuli or whether they are ambiguously associated with the same stimuli. The second factor is whether the stimuli are observed passively or whether the rats move among them, voluntarily or involuntarily. The third factor is whether or not the rats perform specific reinforced responses in the presence of the stimuli. Instances of co-operative behavioral outputs from memory systems that facilitate location discriminations and of competitive outputs that impede discriminations are described.     

Effects of reiteration,hindsight bias,and memory on realism in eyewitness confidence

This study investigated the effects of repetition, memory, feedback, and hindsight bias on the realism in confidence in answers to questions on a filmed kidnapping. In Experiment 1 the participants showed overconfidence in all conditions. In the Repeat condition (‘how confident are you now that your previous answers are correct’) overconfidence was reduced as a consequence of the decrease in confidence in both correct and incorrect answers compared with the Repeat condition when the participants received feedback on their answers and were asked to remember their initial confidence, the confidence level was higher for correct and lower for incorrect answers. In Experiment 2, recalled confidence (the Memory condition) increased compared with the original confidence both for correct and incorrect answers; the effect of this was increased overconfidence. The Hindsight condition showed a decrease in confidence in incorrect answers. The results suggest that a unique hindsight effect may be more clearly present for incorrect than for correct answers. Our study gives further evidence for the malleability of the realism in eyewitness confidence and we discuss both the theoretical and forensic implications of our findings. Copyright © 2000 John Wiley & Sons, Ltd.     

The effects of co-witness discussion on confidence and precision in eyewitness memory reports

We examined the influence of co-witness discussion on the metacognitive regulation of memory reports. Participants (N?=?92) watched a crime video. Later, a confederate confidently agreed with (gave confirming feedback), disagreed with (gave disconfirming feedback), or gave no feedback (control) regarding participants’ answers to questions about the video. Participants who received disconfirming feedback reported fewer fine-grain details than participants in the confirming and control conditions on a subsequent, individual recall test for a different question set. Unexpectedly, this decrease in fine-grain reporting was not accompanied by a decrease in participants’ confidence in the accuracy of their fine-grain responses. These results indicate that receiving social comparative feedback about one’s memory performance can affect rememberers’ metamemorial control decisions, and potentially decrease the level of detail they volunteer in later memory reports. Further research is needed to assess whether these results replicate under different experimental conditions, and to explore the effects of social influences on metamemory.     

The effects of repeatedly recalling a traumatic event on eyewitness memory and suggestibility

ABSTRACT

The aims of this study were to examine the effects of repeatedly recalling a traumatic event on recall performance and eyewitness suggestibility. We also investigated whether these effects were moderated by the type of details recalled and the completeness of retrieval. Participants watched a video depicting a fatal car accident and were randomly allocated to one of four conditions in which they: (1) repeatedly recalled the traumatic (central) details of the event only (trauma-focused); (2) repeatedly recalled the non-traumatic (peripheral) details of the event only (non-trauma focused); (3) repeatedly recalled the entire video (complete); or (4) did not recall the video at all (no-recall control). Results indicated that repeated complete recall was beneficial for memory retention of the entire traumatic event and that, in general, trauma-related (central) post-event information (PEI) was less likely to be reported than trauma-unrelated (peripheral) PEI. It was also found that repeated trauma-focused recall increased trauma-related confabulations. These results not only illustrate the value of repeated complete recall to best preserve the integrity of eyewitness memory, but, perhaps more critically, warn of the dangers of repeatedly questioning witnesses specifically about the central or traumatic details of an event.