Individual differences in children's event memory reports and the narrative elaboration technique

Children between 7 and 8 years old took part in a staged event at school and 1 week later were assessed using a short form of the Wechsler Intelligence scale for children (third edition) and measures of metamemory, narrative ability, and socioeconomic status. Two weeks following the event, children either received narrative elaboration training (NET; K.J. Saywitz & L. Snyder, 1996) and were prompted with the four NET cue cards at interview; received verbal prompts corresponding to the cue card categories, but without prior training; or were presented with the cards at interview without prior training. Children given verbal labels as prompts recalled as much information as children who received NET training and cue cards. Measures of intelligence were predictive of amount recalled for cards-only children but not for the other 2 groups, indicating that differences in recall between low- and high-IQ groups were attenuated when recall was supported by NET training or verbal prompting.     

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 social influence on children's memory reports: the omission and commission error asymmetry

Children in two age groups (7 vs. 12 yrs, N= 174) individually interacted with a stranger and were later interviewed about this event. Right before the interview, each child encountered the stranger once again and he engaged in a conversation where he either suggested that a (central or peripheral) detail originally present in the event had actually not been there or that an originally non-present (central or peripheral) detail had in fact been there. It was hypothesized that the two types of misinformation would result in omission and commission errors respectively. The results showed that the social influence resulted in an asymmetric effect (i.e., more commission than omission errors). Importantly, we also found that the children made more errors with respect to the peripheral detail (a suitcase), compared to the central detail (a passenger). Younger children did not make more errors (neither omission nor commission errors) than older children.     

Reliability of children's reports of depressive symptomatology

The use of self-report measures for the assessment of depression in children has gained wide popularity as a component in the evaluation of children's mental health and wellbeing. However, the extent to which children are reliable and consistent reporters of their depressive symptoms is sometimes called into question. This study examined the test-retest reliability of children's reports of depressive symptomatology on the Reynolds Child Depression Scale (RCDS;Reynolds, 1989a). The sample consisted of 220 children, in grades 3 through 6, representing a crosssection of ethnic groups. Children were tested twice, with a 4-week interval between testings. Results showed a high degree of stability in children's responses to the RCDS, with a test-retest reliability coefficient of 85 for the total sample, and a mean difference between testings of less than 2 points. Test-retest reliability coefficients were also computed for males and females, for each grade, and for white, black, Hispanic, and Asian children. Overall, the results lend strong support for the reliability and stability of children's self-reported depressive symptomatology as assessed by the RCDS.The authors wish to express their appreciation to Dr. Eleanor Chiang and Rovida Mott of the Sacramento Public Schools for their assistance in obtaining school and subject participation.     

Young children's reports of when learning occurred

This study investigated young children's reports of when learning occurred. A total of 96 4-, 5-, and 6-year-olds were recruited from suburban preschools and elementary schools. The children learned an animal fact and a body movement. A week later, children learned another animal fact and another body movement and then answered questions about when the different learning events occurred. Responses of children who responded correctly to control questions about time supported the hypothesis that temporal distance questions would elicit more correct responses than would temporal location questions. Partial support was also found for the hypothesis that behavior learning would generate more correct reports than would fact learning. Implications for characterizations of children's developing understanding of knowledge and for applications of those characterizations in education and eyewitness testimony are discussed.     

Presentation modality affects false memory

Roediger and McDermott (1995) rejuvenated interest in Deese’s (1959) paradigm for producing reliable intrusions and false alarms. Using this paradigm in three experiments, we demonstrated that visual study presentation dramatically reduces the rate of false memories. Only auditory study presentation resulted in equal production of studied and critical items. Correct recall and recognition were unaffected. The suggestion that visual presentation provides a means for discriminating between false and true memories was supported by Experiment 3: Pleasantness rating of study items significantly reduced the creation of false memories regardless of modality.     

How generation affects source memory

Generation effects (better memory for self-produced items than for provided items) typically occur in item memory. Jurica and Shimamura (1999) reported a negative generation effect in source memory, but their procedure did not test participants on the items they had generated. In Experiment 1, participants answered questions and read statements made by a face on a computer screen. The target word was unscrambled, or letters were filled in. Generation effects were found for target recall and source recognition (which person did which task). Experiment 2 extended these findings to a condition in which the external sources were two different faces. Generation had a positive effect on source memory, supporting an overlap in the underlying mechanisms of item and source memory.     

Developmental differences in the effects of repeated interviews and interviewer bias on young children's event memory and false reports

The present study investigated developmental differences in the effects of repeated interviews and interviewer bias on children's memory and suggestibility. Three- and 5-year-olds were singly or repeatedly interviewed about a play event by a highly biased or control interviewer. Children interviewed once by the biased interviewer after a long delay made the most errors. Children interviewed repeatedly, regardless of interviewer bias, were more accurate and less likely to falsely claim that they played with a man. In free recall, among children questioned once after a long delay by the biased interviewer, 5-year-olds were more likely than were 3-year-olds to claim falsely that they played with a man. However, in response to direct questions, 3-year-olds were more easily manipulated into implying that they played with him. Findings suggest that interviewer bias is particularly problematic when children's memory has weakened. In contrast, repeated interviews that occur a short time after a to-be-remembered event do not necessarily increase children's errors, even when interviews include misleading questions and interviewer bias. Implications for developmental differences in memory and suggestibility are discussed.     

Working memory affects false memory production for emotional events

Whereas a link between working memory (WM) and memory distortions has been demonstrated, its influence on emotional false memories is unclear. In two experiments, a verbal WM task and a false memory paradigm for negative, positive or neutral events were employed. In Experiment 1, we investigated individual differences in verbal WM and found that the interaction between valence and WM predicted false recognition, with negative and positive material protecting high WM individuals against false remembering; the beneficial effect of negative material disappeared in low WM participants. In Experiment 2, we lowered the WM capacity of half of the participants with a double task request, which led to an overall increase in false memories; furthermore, consistent with Experiment 1, the increase in negative false memories was larger than that of neutral or positive ones. It is concluded that WM plays a critical role in determining false memory production, specifically influencing the processing of negative material.     

Validating reports of poor childhood memory

Recent evidence indicates that judgements about the quality of one's own childhood memory can be influenced experimentally, for example by manipulating ease of retrieval. This has led to the suggestion that judgements of poor memory made by clients in therapy may not be reliable. We therefore investigated whether individuals who judge themselves to have poor memory for their childhood do in fact score worse on a standardized test of autobiographical memory. Matched groups of individuals reporting poor and normal memory for childhood were administered the Autobiographical Memory Interview. Consistent with a previous study of neurological patients, subjective judgements were associated with performance on both personal semantic memory and autobiographical incident memory. Copyright © 2002 John Wiley & Sons, Ltd.     

Cross-cultural differences in eyewitness memory reports

Increasingly, investigators conduct interviews with eyewitnesses from different cultures. The culture in which people have been socialised can impact the way they encode, remember, and report information about their experiences. We examined whether eyewitness memory reports of mock witnesses from collectivistic (sub-Saharan Africa) and individualistic (Northern Europe) cultures differed regarding quantity and quality of central and background details reported. Mock witnesses (total N = 200) from rural Ghana, urban Ghana, and the Netherlands were shown stimuli scenes of crimes in Dutch and Ghanaian settings and provided free and cued recalls. Individualistic culture mock witnesses reported the most details, irrespective of detail type. For each cultural group, mock witnesses reported more correct central details when crime was witnessed in their own native setting than a non-native setting, though for different recall domains. The findings provide insight for legal and investigative professionals as well as immigration officials eliciting memory reports in cross-cultural contexts.     

Gaze direction affects visuo-spatial short-term memory

Hemispheric asymmetries were investigated by changing the horizontal position of stimuli that had to be remembered in a visuo-spatial short-term memory task. Observers looked at matrices containing a variable number of filled squares on the left or right side of the screen center. At stimulus offset, participants reproduced the positions of the filled squares in an empty response matrix. Stimulus and response matrices were presented in the same quadrant. We observed that memory performance was better when the matrices were shown on the left side of the screen. We distinguished between recall strategies that relied on visual or non-visual (verbal) cues and found that the effect of gaze position occurred more reliably in participants using visual recall strategies. Overall, the results show that there is a solid enhancement of visuo-spatial short-term memory when observers look to the left. In contrast, vertical position had no influence on performance. We suggest that unilateral gaze to the left activates centers in the right hemisphere contributing to visuo-spatial memory.     

Lateral head turning affects temporal memory

Spatial attention is a key factor in the exploration and processing of the surrounding environment, and plays a role in linking magnitudes such as space, time, and numbers. The present work evaluates whether shifting the coordinates of spatial attention through rotational head movements may affect the ability to estimate the duration of different time intervals. A computer-based implicit timing task was employed, in which participants were asked to concentrate and report verbally on colour changes of sequential stimuli displayed on a computer screen; subsequently, they were required to reproduce the temporal duration (ranging between 5 and 80 sec.) of the perceived stimuli using the computer keyboard. There was statistically significant overestimation of the 80-sec. intervals exclusively on the rightward rotation head posture, whereas head posture did not affect timing performances on shorter intervals. These findings support the hypothesis that the coordinates of spatial attention influence the ability to process time, consistent with the existence of common cortical metrics of space and time in healthy humans.     

Item strength affects working memory capacity

Do the processing and online manipulation of stimuli that are less familiar require more working memory (WM) resources? Is it more difficult to solve demanding problems when the symbols involved are less rather than more familiar? We explored these questions with a dual-task paradigm in which subjects had to solve algebra problems of different complexities while simultaneously holding novel symbol–digit associations in WM. The symbols were previously unknown Chinese characters, whose familiarity was manipulated by differential training frequency with a visual search task for nine hour-long sessions over 3 weeks. Subsequently, subjects solved equations that required one or two transformations. Before each trial, two different integers were assigned to two different Chinese characters of the same training frequency. Half of the time, those characters were present as variables in the equation and had to be substituted for the corresponding digits. After attempting to solve the equation, subjects had to recognize which two characters were shown immediately before that trial and to recall the integer associated with each. Solution accuracy and response times were better when the problems required one transformation only; variable substitution was not required; or the Chinese characters were high frequency. The effects of stimulus familiarity increased as the WM demands of the equation increased. Character–digit associations were also recalled less well with low-frequency characters. These results provide strong support that WM capacity depends not only on the number of chunks of information one is attempting to process but also on their strength or familiarity.     

Multisensory integration affects visuo-spatial working memory

In the present study, we investigate how spatial attention, driven by unisensory and multisensory cues, can bias the access of information into visuo-spatial working memory (VSWM). In a series of four experiments, we compared the effectiveness of spatially-nonpredictive visual, auditory, or audiovisual cues in capturing participants' spatial attention towards a location where to-be-remembered visual stimuli were or were not presented (cued/uncued trials, respectively). The results suggest that the effect of peripheral visual cues in biasing the access of information into VSWM depend on the size of the attentional focus, while auditory cues did not have direct effects in biasing VSWM. Finally, spatially congruent multisensory cues showed an enlarged attentional effect in VSWM as compared to unimodal visual cues, as a likely consequence of multisensory integration. This latter result sheds new light on the interplay between spatial attention and VSWM, pointing to the special role exerted by multisensory (audiovisual) cues.     

Reminiscence and hypermnesia in children's eyewitness memory

Three experiments examined reminiscence and hypermnesia in 5- and 6-year-olds' memory for an event across repeated interviews that occurred either immediately afterward (Experiment 1) or after a 6-month delay (Experiments 2 and 3). Reminiscence (recall of new information) was reliably obtained in all of the experiments, although the numbers of new items recalled were fewer after a delay than when the interviews occurred immediately afterward. Hypermnesia (increasing total recall over repeated recall attempts) was obtained only in Experiment 1 when interviews occurred immediately and 24 h after the event.     

Central executive involvement in children's spatial memory

Previous research with adults found that spatial short-term and working memory tasks impose similar demands on executive resources. We administered spatial short-term and working memory tasks to 8- and 11-year-olds in three separate experiments. In Experiments 1 and 2 an executive suppression task (random number generation) was found to impair performances on a short-term memory task (Corsi blocks), a working memory task (letter rotation), and a spatial visualisation task (paper folding). In Experiment 3 an articulatory suppression task only impaired performance on the working memory task. These results suggest that short-term and working memory performances are dependent on executive resources. The degree to which the short-term memory task was dependent on executive resources was expected to be related to the amount of experience children have had with such tasks. Yet we found no significant age-related suppression effects. This was attributed to differences in employment of cognitive strategies by the older children.     

Peer influence on event reports among adolescents and young adults

When two or more people witness an event together, the event report from one person can influence others’ reports. In the current study we examined the role of age and motivational factors on peer influence regarding event reports in adolescents and young adults. Participants (N=249) watched a short video of a robbery then answered questions with no co-witness information or with information believed to be from a co-witness. Public and private response conditions were included to explore motivations for peer influence. Co-witness information influenced participants’ responses, although the effect was equally strong in the private and the public co-witness conditions. Peer influence on event reports was steady across a large age range (11- to 25-year-olds).