Examining the effects of memory specificity and perceptual load on susceptibility to misleading information

Our study aimed to examine the role of perceptual load in eyewitness memory and susceptibility to misinformation and establish whether trait-based memory specificity protects against misinformation. Participants (n = 264) viewed a video depicting a crime and completed a memory questionnaire immediately afterwards and 1 week later. Memory specificity was measured using the Autobiographical Memory Test (AMT). Higher AMT scores were associated with better memory accuracy. Performance was worse in the high load compared to the low load condition at immediate recall. However, this effect was not seen for every question and load did not influence eyewitness identifications. To test the possibility that load effects were not fully captured by the questionnaire in experiment 1, we conducted a second experiment (n = 120) where we systematically manipulated misinformation about central and peripheral details. We found no effects. Our findings suggest that high perceptual load enhances eyewitness suggestibility, while specific autobiographical memory protects against misinformation.     

Editing misleading information from memory: Evidence for the coexistence of original and postevent information

When misleading postevent information biases one’s memory for an event, what is the fate of the original, accurate information? One possibility is that the new information and the original information coexist in memory, but that the former is simply more accessible. A second hypothesis suggests that the new information replaces the old, and memory is irreversibly altered. Using various retrieval techniques, Loftus and her associates (Greene, Flynn, & Loftus, 1982; Loftus, 1979a, 1979b) have failed repeatedly in attempts to recover original memories after postevent biasing, a finding that supports the alteration hypothesis. In the present study, postevent biasing was demonstrated in two experiments. In each experiment, some subjects were given a warning that the postevent information had included a few inaccurate details. These subjects were able to edit out the inaccurate details and to recover the original facts when the warning came as much as 45 rain after they had read the misleading information, a result that argues for the coexistence of memories. Successful recovery of the original memories was apparently due to the clarity of the warning and to an improved technique for assessing the retrieval of original memories.     

Context reinstatement effects on eyewitness memory in autism spectrum disorder

The Cognitive Interview is among the most widely accepted forms of police interviewing techniques; however, it is ineffective for witnesses with autism spectrum disorder (ASD). One of its main components involves mentally reinstating the internal and external context that was experienced at encoding. We report evidence showing that it is the mental reinstatement instructions in the absence of any physical cues that individuals with ASD find difficult. In more supported conditions where they physically return to the same environment in which they learnt the material, they recall as much as their typical counterparts. Our findings indicate that recall in ASD is aided by context, but only when supported by the physical environment. These findings have important implications for investigative interviewing procedures for witnesses with ASD.     

Immediate and persisting effects of misleading questions and hypnosis on memory reports

Immediate and persisting effects of misleading questions and hypnosis on memory reports were assessed. After listening to a story, 52 highly suggestible students and 59 low and medium suggestible students were asked misleading or neutral questions in or out of hypnosis. All participants were then asked neutral questions without hypnosis. Both hypnosis and misleading questions significantly increased memory errors, and misleading questions produced significantly more errors than did hypnosis. The 2 effects were additive, so that misleading questions in hypnosis produced the greatest number of errors. There were no significant interactions with level of hypnotic suggestibility. Implications of these findings for the per se exclusion of posthypnotic testimony are discussed.     

The effects of misleading and inconsistent postevent information on children's recollections of criterion-learned information.

Similar experimental procedures are used in misinformation studies and in retroactive inhibition studies. Despite these similarities, the findings of these studies have suggested that misleading postevent information and inconsistent postevent information would have different effects on children's recollections. To examine this hypothesis, 28 seven-year-olds learned a target game to criterion. Two days later, they were administered either type of postevent information on either one or three occasions. When the children were tested 3 weeks later, the results showed that even criterion-learned information could be affected detrimentally by exposure to misleading or inconsistent postevent information. Notably, children who were administered misinformation on one occasion reported more target information than children in all other groups. It is suggested that exposure to misinformation had a facilitative effect on these children's recollections.     

But I thought it was Mickey Mouse: the effects of new postevent information on 18-month-olds' memory

Two experiments examined the effects of postevent information on 18-month-olds' event memory. Experiment 1 (N=60) explored whether children's memory was reinstated when action information was eliminated from the reinstatement and only object information was introduced. Experiment 2 (N=48) examined children's recall when either (a). information about the objects' target actions was replaced with new action information or (b). the original training objects were replaced with new objects. In an elicited-imitation paradigm, children were trained to perform six target actions, watched a video reinstatement 10 weeks later, and were tested for recall 24 h after reinstatement. Two results were found. First, a video reminder eliminating action information reinstated children's memory as effectively as a video containing object and action information. Second, children were reminded of their past training when during reinstatement action information was preserved and new objects were presented but were not reminded when object information was preserved and new actions were presented.     

Visual memory,the long and the short of it: A review of visual working memory and long-term memory

The majority of research on visual memory has taken a compartmentalized approach, focusing exclusively on memory over shorter or longer durations, that is, visual working memory (VWM) or visual episodic long-term memory (VLTM), respectively. This tutorial provides a review spanning the two areas, with readers in mind who may only be familiar with one or the other. The review is divided into six sections. It starts by distinguishing VWM and VLTM from one another, in terms of how they are generally defined and their relative functions. This is followed by a review of the major theories and methods guiding VLTM and VWM research. The final section is devoted toward identifying points of overlap and distinction across the two literatures to provide a synthesis that will inform future research in both fields. By more intimately relating methods and theories from VWM and VLTM to one another, new advances can be made that may shed light on the kinds of representational content and structure supporting human visual memory.     

The effects of cortisol increase on long-term memory retrieval during and after acute psychosocial stress

In this study the effects of stress-induced cortisol increases on long-term memory retrieval during and after acute psychosocial stress were examined. Seventy male students were exposed to either a psychosocial stress task or to a non-stressful control task. During and after this task, retrieval was tested for idiosyncratic emotionally negative and neutral word pair associations that were learned 1 day or 5 weeks earlier. Within the stress condition, retrieval of negative words, 5 weeks after learning, was impaired both during and after the stress task compared to the control group. Further, during the stress task, when sympathetic activity was enhanced, impaired retrieval of both neutral and emotional words was significantly related to enhanced cortisol response. In contrast, after the stress task, when cortisol levels were still increased but sympathetic activity was low again, no association was found between cortisol increase and retrieval of either neutral or emotional material. These results are in line with the previous animal research showing that when arousal is high, cortisol increase can impair memory retrieval.     

The personalisation method applied to a working memory task: Evidence of long-term working memory effects

Ericsson and Kintsch (1995) proposed that, in situations of expertise, individuals can overcome working memory limitations by using long-term working memory. It allows a greater capacity than working memory thanks to long-term memory encoding and retrieving. To test this characteristic, an adaptation of Daneman and Carpenter's (1980) reading span was used. To operationalise expertise, the personalisation method (Guida & Tardieu, 2005) was employed. In Experiment 1, a personalised group, which read reading span sentences that mentioned familiar locations, was compared to a nonpersonalised group, which read sentences with unfamiliar locations. In Experiment 2, a personalised group, which read reading span sentences with neutral locations, was encouraged to mentally personalise these locations by thinking about known locations. This group was compared to a nonpersonalised group, which was encouraged to think about unknown locations. The personalised groups were expected to store and retrieve information in long-term memory via long-term working memory more easily than the nonpersonalised groups, which had to count massively on working memory. The results showed that personalisation enhanced reading span and confirmed one implication of the long-term working memory theory: high- and low-reading-span differences could also be due to long-term memory retrieval. Finally, these results are interpreted in terms of interaction between working memory size and long-term memory knowledge, showing that participants with a lower reading span benefited more from high domain knowledge than participants with a higher reading span.     

d-Cycloserine: effects on long-term retention of a conditioned response and on memory for contextual attributes.

d-Cycloserine (DCS), a partial agonist of the glycine recognition site of the N-methyl d-aspartate receptor, has beneficial effects on learning and memory. In order to investigate its potential to influence learning and memory of both the response and the stimulus attributes of training, male Sprague-Dawley albino rats were trained in a one-trial inhibitory avoidance task following an acute intraperitoneal injection of DCS (3 mg/kg) or an equal volume of saline. In order to measure memory for stimulus attributes, testing involved a context shift paradigm, in which subjects are tested in either the environment of training or a different one. Good memory for the contextual attributes of training is indicated by poor performance in the alternate context. Retention was assessed either 1, 7, or 14 days after training. At 1 day, Saline subjects were affected by a change in context, while DCS subjects were not. In subjects tested 1 week following training, Saline subjects were no longer affected by a change in context, in that they performed the avoidance response in both contexts. This indicates the forgetting of stimulus attributes in Saline subjects. DCS subjects did show the context shift effect at 1 week, indicating the retention of stimulus attributes. Finally, Saline subjects demonstrated the context shift rebound at 14 days, while DCS subjects performed equivalently in both contexts. Taken together, these data suggest that DCS may enhance retention of fear and slow the forgetting of stimulus attributes.     

Visual long-term memory and change blindness: Different effects of pre- and post-change information on one-shot change detection using meaningless geometric objects

To clarify the relationship between visual long-term memory (VLTM) and online visual processing, we investigated whether and how VLTM involuntarily affects the performance of a one-shot change detection task using images consisting of six meaningless geometric objects. In the study phase, participants observed pre-change (Experiment 1), post-change (Experiment 2), or both pre- and post-change (Experiment 3) images appearing in the subsequent change detection phase. In the change detection phase, one object always changed between pre- and post-change images and participants reported which object was changed. Results showed that VLTM of pre-change images enhanced the performance of change detection, while that of post-change images decreased accuracy. Prior exposure to both pre- and post-change images did not influence performance. These results indicate that pre-change information plays an important role in change detection, and that information in VLTM related to the current task does not always have a positive effect on performance.     

The effects of word co-occurrence on short-term memory: associative links in long-term memory affect short-term memory performance

In immediate serial recall tasks, high-frequency words are recalled better than low-frequency words. This has been attributed to high-frequency words' being better represented and providing more effective support to a redintegration process at retrieval (C. Hulme et al., 1997). In studies of free recall, there is evidence that frequency of word co-occurrence, rather than word frequency per se, may explain the recall advantage enjoyed by high-frequency words (J. Deese, 1960). The authors present evidence that preexposing pairs of low-frequency words, so as to create associative links between them, has substantial beneficial effects on immediate serial recall performance. These benefits, which are not attributable to simple familiarization with the words per se, do not occur for high-frequency words. These findings indicate that associative links between items in long-term memory have important effects on short-term memory performance and suggest that the effects of word frequency in short-term memory tasks are related to differences in interitem associations in long-term memory.     

Influences of misleading postevent information: misinformation interference and acceptance

Because of the biasing nature of retrieval tests, evidence that the introduction of misleading postevent information will impair the memory for an original event has recently been in dispute. In two experiments, a retrieval test sensitive to both biasing effects of misinformation (misinformation acceptance) and influences of the misinformation on memory (misinformation interference) was used. Both experiments demonstrated misinformation acceptance, and one of the experiments suggested that misinformation interferes with the ability to remember the original event. Two misinformation interference hypotheses are evaluated; they suggest that the misinformation may have either impaired memory or led to confusion regarding what had occurred during the event.     

Cuing effects and associative information in recognition memory

Item recognition requires discrimination of studied words from nonstudied words. Associative recognition requires subjects to discriminate studied word groups from recombinations of words from different groups. Cued recognition requires the same old-new discrimination as item recognition, but list items are presented as cues along with the test item. The results from three experiments show (1) little or no effect of cuing for low-frequency words, but (2) positive cuing effects for high-frequency words; (3) increasing levels of overall performance with increases in study time, but (4) unchanging effects of cuing with study time; and (5) stronger positive cuing effects for two cues than for one cue. Five models (Independent Cue Model, Matrix model, MINERVA 2, SAM, and TODAM) were fit to the data of Experiment 1. Each model has trouble with at least one aspect of the results. Theoretical implications and modifications are discussed at length.     

Complexity effects in visuo-spatial working memory: Implications for the role of long-term memory

Several studies have shown that the capacity of visuo-spatial working memory is limited by complexity. Using a variant of the Corsi blocks task, this paper investigates the effect of complexity of the to-beremembered path on visuo-spatial memory span. Redundancy was determined by three Gestalt principles: symmetry, repetition, and continuation. Experiment 1 revealed an effect of path complexity. The subsequent experiments explored whether the superiority for recall of structured over complex paths can be attributed solely to the operation of visuo-spatial working memory, or whether it also reflects the use of long-term knowledge. Experiment 2 demonstrated that the effect of complexity remained, even when the mechanisms for visuo-spatial coding were removed by a secondary visuo-spatial task. In Experiments 3 and 4 subjects were trained in the recall of complex paths. This led to the creation of long-term memory representations for these paths, as shown by an improvement in their span, and a concomitant lack of transfer to new paths. Finally, Experiment 5 showed that one prior repetition of a complex path was sufficient to produce specific and long-term learning effects. These results point to the involvement of long-term memory processes in the temporary retention of visuo-spatial material for which representations exist in long-term memory. They also suggest that the effect of complexity may provide a tractable technique for investigating the mechanisms underlying the limits of visuo-spatial short-term storage.     

Complexity effects in visuo-spatial working memory: implications for the role of long-term memory

Several studies have shown that the capacity of visuo-spatial working memory is limited by complexity. Using a variant of the Corsi blocks task, this paper investigates the effect of complexity of the to-be-remembered path on visuo-spatial memory span. Redundancy was determined by three Gestalt principles: symmetry, repetition, and continuation. Experiment 1 revealed an effect of path complexity. The subsequent experiments explored whether the superiority for recall of structured over complex paths can be attributed solely to the operation of visuo-spatial working memory, or whether it also reflects the use of long-term knowledge. Experiment 2 demonstrated that the effect of complexity remained, even when the mechanisms for visuo-spatial coding were removed by a secondary visuo-spatial task. In Experiments 3 and 4 subjects were trained in the recall of complex paths. This led to the creation of long-term memory representations for these paths, as shown by an improvement in their span, and a concomitant lack of transfer to new paths. Finally, Experiment 5 showed that one prior repetition of a complex path was sufficient to produce specific and long-term learning effects. These results point to the involvement of long-term memory processes in the temporary retention of visuo-spatial material for which representations exist in long-term memory. They also suggest that the effect of complexity may provide a tractable technique for investigating the mechanisms underlying the limits of visuo-spatial short-term storage.     

Telling a story or telling it straight: the effects of entertaining versus accurate retellings on memory

People retell events for different reasons. Sometimes they try to be accurate, other times entertaining. What characterizes retellings from different perspectives? How does retelling perspective affect later recall of events? In the current research, participants retold a story either three times or not at all. By instruction, retellings were either entertaining or accurate. Compared to accurate retellings, entertaining retellings contained more affect, but fewer sensory references. On a subsequent memory test, participants who retold with an accuracy goal recalled the greatest number of story events, and their recall protocols were the most accurate and detailed, and least exaggerated. However, recognition memory did not differ across groups, suggesting that differences in retrieval structures (necessary for recall but not recognition) were key to understanding later differences in memory. Compared to telling it straight, the creative process of telling a story leads to qualitative and quantitative changes in later recall. Copyright © 2004 John Wiley & Sons, Ltd.     

Intrusive effects of implicitly processed information on explicit memory

This study described the interference of implicitly processed information on the memory for explicitly processed information. Participants studied a list of words either auditorily or visually under instructions to remember the words (explicit study). They were then visually presented another word list under instructions which facilitate implicit but not explicit processing. Following a distractor task, memory for the explicit study list was tested with either a visual or auditory recognition task that included new words, words from the explicit study list, and words implicitly processed. Analysis indicated participants both failed to recognize words from the explicit study list and falsely recognized words that were implicitly processed as originating from the explicit study list. However, this effect only occurred when the testing modality was visual, thereby matching the modality for the implicitly processed information, regardless of the modality of the explicit study list. This "modality effect" for explicit memory was interpreted as poor source memory for implicitly processed information and in light of the procedures used. as well as illustrating an example of "remembering causing forgetting."     

The effects of anxious mood induction on suggestibility to misleading post‐event information

Little research has been carried out into the effects of anxious mood at the time of either the encoding of misleading post‐event information or the time of its possible retrieval, on subsequent suggestibility. Participants comprised 160 first‐year undergraduates. Using a standard suggestibility paradigm, half of all participants were exposed to misleading information while half were non‐misinformed controls. In addition there were four state anxiety conditions, dependent on the timing of the anxious mood induction: at the time of encoding misleading information; at retrieval only; at both encoding and retrieval; or at neither encoding nor retrieval (controls). Results showed memory accuracy for non‐suggestible items was unaffected by the anxious mood induction. With respect to suggestibility, there was a strong effect of misleading information. In addition, within the misinformed group, all three groups who experienced the anxious mood induction were significantly less suggestible than controls. These findings are discussed both in terms of theories of anxiety and cognition and the applied implications for the increasing use by the police of video‐recorded witness interviews. Copyright © 2004 John Wiley & Sons, Ltd.