Age differences in source forgetting: effects on reality monitoring and on eyewitness testimony

Age differences in memory for the source of memories were investigated using two different experimental paradigms. Experiment 1 used a reality monitoring paradigm. A series of actions were either performed, imagined, or watched, and subjects were later tested for their ability to recognize the actions and identify their origins. Elderly subjects made more false positive responses than did young subjects, and they made more source confusion errors, attributing actions to the wrong sources. Both new and imagined actions were most often misclassified as watched. Experiment 2 used an eyewitness testimony paradigm. After watching a film, subjects read a written version of the story. A recognition test showed that elderly subjects were more often misled by false information in the story than were the younger subjects, and were more confident that their erroneous responses were correct. The findings suggest that a decline in memory for sources may diminish the accuracy of elderly witnesses.     

Binding actions and scenes in visual long-term memory

How does visual long-term memory store representations of different entities (e.g., objects, actions, and scenes) that are present in the same visual event? Are the different entities stored as an integrated representation in memory, or are they stored separately? To address this question, we asked observers to view a large number of events; in each event, an action was performed within a scene. Afterward, the participants were shown pairs of action–scene sets and indicated which of the two they had seen. When the task required recognizing the individual actions and scenes, performance was high (80 %). Conversely, when the task required remembering which actions had occurred within which scenes, performance was significantly lower (59 %). We observed this dissociation between memory for individual entities and memory for entity bindings across multiple testing conditions and presentation durations. These experiments indicate that visual long-term memory stores information about actions and information about scenes separately from one another, even when an action and scene were observed together in the same visual event. These findings also highlight an important limitation of human memory: Situations that require remembering actions and scenes as integrated events (e.g., eyewitness testimony) may be particularly vulnerable to memory errors.     

Calibration trumps confidence as a basis for witness credibility

Confident witnesses are deemed more credible than unconfident ones, and accurate witnesses are deemed more credible than inaccurate ones. But are those effects independent? Two experiments show that errors in testimony damage the overall credibility of witnesses who were confident about the erroneous testimony more than that of witnesses who were not confident about it. Furthermore, after making an error, less confident witnesses may appear more credible than more confident ones. Our interpretation of these results is that people make inferences about source calibration when evaluating testimony and other social communication.     

False recollection of the role played by an actor in an event

Two experiments demonstrated that eyewitnesses more frequently associate an actor with the actions of another person when those two people had appeared together in the same event, rather than in different events. This greater likelihood of binding an actor with the actions of another person from the same event was associated with high-confidence recognition judgments and “remember” responses in a remember–know task, suggesting that viewing an actor together with the actions of another person led participants to falsely recollect having seen that actor perform those actions. An analysis of age differences provided evidence that familiarity also contributed to false recognition independently of a false-recollection mechanism. In particular, older adults were more likely than young adults to falsely recognize a novel conjunction of a familiar actor and action, regardless of whether that actor and action were from the same or from different events. Older adults’ elevated rate of false recognition was associated with intermediate confidence levels, suggesting that it stemmed from increased reliance on familiarity rather than from false recollection. The implications of these results are discussed for theories of conjunction errors in memory and of unconscious transference in eyewitness testimony.     

Paradoxical decrease of imitation performance with age in children

Imitation development was studied in a cross-sectional design involving 174 primary-school children (aged 6–10), focusing on the effect of actions' complexity and error analysis to infer the underlying cognitive processes. Participants had to imitate the model's actions as if they were in front of a mirror (‘specularly’). Complexity varied across three levels: movements of a single limb; arm and leg of the same body side; or arm and leg of opposite body sides. While the overall error rate decreased with age, this was not true of all error categories. The rate of ‘side’ errors (using a limb of the wrong body side) paradoxically increased with age (from 9 years). However, with increasing age, the error rate also became less sensitive to the complexity of the action. This pattern is consistent with the hypothesis that older children have the working memory (WM) resources and the body knowledge necessary to imitate ‘anatomically’, which leads to additional side errors. Younger children might be paradoxically free from such interference because their WM and/or body knowledge are insufficient for anatomical imitation. Yet, their limited WM resources would prevent them from successfully managing the conflict between spatial codes involved in complex actions (e.g. moving the left arm and the right leg). We also found evidence that action side and content might be stored in separate short-term memory (STM) systems: increasing the number of sides to be encoded only affected side retrieval, but not content retrieval; symmetrically, increasing the content (number of movements) of the action only affected content retrieval, but not side retrieval. In conclusion, results suggest that anatomical imitation might interfere with specular imitation at age 9 and that STM storages for side and content of actions are separate.     

Negative prospective memory: Remembering not to perform an action

Sometimes it is important to remember not to perform an action, such as remembering to stop taking seasonal allergy medicine when it is no longer needed. Mistakes in accomplishing this goal can involve prospective memory commission errors when individuals mistakenly perform a prospective response. In two experiments, we investigated the role of attentional resources in preventing prospective memory errors to cues that had been associated with a habitual prospective response. In Phase 1 of our experiments, participants performed a prospective memory task during which they either routinely responded to prospective memory cues or responded to these cues one time only. On a subsequent prospective memory task, the participants who had routinely responded to prospective memory cues were vulnerable to commission errors when their attentional resources were taxed. By contrast, dividing attention did not increase commission errors to cues that had not been routinely performed on an earlier task. These data indicate that attentional resources are needed to withhold making habitual prospective memory responses, and they suggest that inhibitory failures are a cause of these prospective memory errors. Finally, we suggest a broader definition of prospective memory that includes remembering to withhold performing actions.     

Source confusion influences the effectiveness of the autobiographical IAT

We examined the claim that the autobiographical Implicit Association Test (aIAT) can detect concealed memories. Subjects read action statements (e.g., “break the toothpick”) and either performed the action or completed math problems. They then imagined some of these actions and some new actions. Two weeks later, the subjects completed a memory test and then an aIAT in which they categorized true and false statements (e.g., “I am in front of the computer”) and whether they had or had not performed actions from Session 1. For half of the subjects, the nonperformed statements were actions that they saw but did not perform; for the remaining subjects, these statements were actions that they saw and imagined but did not perform. Our results showed that the aIAT can distinguish between true autobiographical events (performed actions) and false events (nonperformed actions), but that it is less effective, the more that subjects remember performing actions that they did not really perform. Thus, the diagnosticity of the aIAT may be limited.     

Visual capture and human error

We investigated relationships between everyday error rates, susceptibility to stimulus‐driven (i.e. external) capture of visual attention and working memory. Using an eye‐tracking task called the antisaccade paradigm, we found that relatively error‐prone subjects made significantly more unintended, stimulus‐driven eye movements. This finding suggests a link between error‐proneness and a tendency towards environmental (versus volitional) control of behaviour. No evidence was found for a connection between working memory capacity and error proneness or eye movements, though range restriction may have affected the working memory results. The findings are compatible with the view that some mishaps stem from environmental capture and triggering of inappropriate actions, and that individuals vary in their susceptibility to capture. Some implications are that: (1) mishaps might be reduced by redesigning tasks to reduce capture errors, e.g. by restructuring critical tasks to eliminate action sequences with common initial stages; (2) the antisaccade task may be a useful dependent measure in research on how stressors (e.g. fatigue, noise, temperature) increase the likelihood of mishaps. Specifically, since antisaccade performance was correlated with reports of real‐world mistakes in the current study, antisaccade scores may allow useful predictions about how accident probability varies as a function of different conditions. Copyright © 1999 John Wiley & Sons, Ltd.     

Schema‐driven source misattribution errors: remembering the expected from a witnessed event

When recollection is difficult, people may use schematic processing to enhance memory. Two experiments showed that a delay between witnessing and recalling a visual sequence increases schematic processing, resulting in stereotypic memory errors. Participants watched a slide show of a man and a woman performing stereotype‐consistent and stereotype‐inconsistent actions, followed by an immediate or delayed memory test. Over a two‐day delay, stereotype‐inconsistent actions were increasingly misremembered as having been performed by the stereotype‐consistent actor (Experiment 1). All the source errors increased, regardless of stereotype consistency, when the wrong actor was suggested. When we merely suggested that ‘someone’ performed an action (Experiment 2), only stereotype‐consistent source errors were increased. Although visual scenes are typically well remembered, these results suggest that when memory fades, reliance on schemata increases, leading to increased stereotypic memory errors. Copyright © 2007 John Wiley & Sons, Ltd.     

Verb retrieval in brain-damaged subjects: 2. Analysis of errors

Verb retrieval for action naming was assessed in 53 brain-damaged subjects by administering a standardized test with 100 items. In a companion paper (Kemmerer & Tranel, 2000), it was shown that impaired and unimpaired subjects did not differ as groups in their sensitivity to a variety of stimulus, lexical, and conceptual factors relevant to the test. For this reason, the main goal of the present study was to determine whether the two groups of subjects manifested theoretically interesting differences in the kinds of errors that they made. All of the subjects' errors were classified according to an error coding system that contains 27 distinct types of errors belonging to five broad categories-verbs, phrases, nouns, adpositional words, and "other" responses. Errors involving the production of verbs that are semantically related to the target were especially prevalent for the unimpaired group, which is similar to the performance of normal control subjects. By contrast, the impaired group had a significantly smaller proportion of errors in the verb category and a significantly larger proportion of errors in each of the nonverb categories. This relationship between error rate and error type is consistent with previous research on both object and action naming errors, and it suggests that subjects with only mild damage to putative lexical systems retain an appreciation of most of the semantic, phonological, and grammatical category features of words, whereas subjects with more severe damage retain a much smaller set of features. At the level of individual subjects, a wide range of "predominant error types" were found, especially among the impaired subjects, which may reflect either different action naming strategies or perhaps different patterns of preservation and impairment of various lexical components. Overall, this study provides a novel addition to the existing literature on the analysis of naming errors made by brain-damaged subjects. Not only does the study advance our knowledge of the relatively under investigated topic of action naming errors, but it also approaches the analysis from the point of view of a detailed, theoretically motivated, and reliable error coding system.     

Photograph‐induced memory errors: When photographs make people claim they have done things they have not

Photographs can serve as valuable memory aids but can also contribute to memory inaccuracies. The present studies examine whether photographs can make people claim they performed an action that they did not in fact perform. Participants performed and imagined performing various actions (e.g. break the pencil, open the envelope) and later viewed photographs of actions in their completed states or read the names of the actions without an accompanying photograph. Results showed that participants were more likely to falsely claim to have performed actions that they did not actually perform after having seen a photograph of the completed action. When items were not imagined at all, such photograph‐induced memory errors increased with the number of presentations of the photographs. Actions falsely claimed as performed were rated with high confidence. These findings suggest that photographs can mislead people as to what they did or did not do. Copyright © 2009 John Wiley & Sons, Ltd.     

When Eyewitnesses Talk

ABSTRACT— When two people witness an event, they often discuss it. Because memory is not perfect, sometimes this discussion includes errors. One person's errors can become part of another person's account, and this proliferation of error can lead to miscarriages of justice. In this article, we describe the social and cognitive processes involved. Research shows how people combine information about their own memory with other people's memories based on factors such as confidence, perceived expertise, and the social cost of disagreeing with other people. We describe the implications of this research for eyewitness testimony.     

Differential reliance of chimpanzees and humans on automatic and deliberate control of motor actions

Humans are often unaware of how they control their limb motor movements. People pay attention to their own motor movements only when their usual motor routines encounter errors. Yet little is known about the extent to which voluntary actions rely on automatic control and when automatic control shifts to deliberate control in nonhuman primates. In this study, we demonstrate that chimpanzees and humans showed similar limb motor adjustment in response to feedback error during reaching actions, whereas attentional allocation inferred from gaze behavior differed. We found that humans shifted attention to their own motor kinematics as errors were induced in motor trajectory feedback regardless of whether the errors actually disrupted their reaching their action goals. In contrast, chimpanzees shifted attention to motor execution only when errors actually interfered with their achieving a planned action goal. These results indicate that the species differed in their criteria for shifting from automatic to deliberate control of motor actions. It is widely accepted that sophisticated motor repertoires have evolved in humans. Our results suggest that the deliberate monitoring of one’s own motor kinematics may have evolved in the human lineage.     

An emerging research agenda for investigative interviewing: hypotheses from the narrative action system

The present issue of JIP-OP brings together an intriguing range of papers that cover a wide range of aspects of testimony and aspects of investigative interviewing. They show how the considerations of how testimony is obtained is broadening out from the memory improvement strategies that once dominated this area with attempts to detect deception, to cover many aspects of how testimony is obtained. This draws attention to the need for more careful examination of the variations in testimony eliciting processes that will be responsive to differences in context and crime. A research agenda is therefore proposed that draws on developments in the understanding of psychological differences between crimes. This research would study the relationship between the psychological processes underpinning offence actions and the interview behaviour of suspects or witnesses. With regard to suspects, recent developments in the modelling of offence style have indicated a narrative basis (narrative action system model) for understanding the patterns of offence actions and the perpetrator's psychological background and characteristics that can be inferred from these. It is therefore suggested that the Hero's Quest, Professional's Adventure, Revenger's Tragedy, and Victim's Irony offending narratives and the Object, Vehicle, and Person victim roles assigned within these, may provide a fruitful link to different patterns of interview behaviour, with consequent implications for approaches to interviewing. Copyright © 2009 John Wiley & Sons, Ltd.     

Using heteromodal communication to optimize knowledge and awareness

Accurate, error-free communication is essential for success in many areas, such as eyewitness testimony, human factors design, business, education, and personal relationships. Traditional communication uses similar modalities: Participants communicate by talking or by writing, but not both at the same time with the same addressees. New communicative technologies have broadened this vista. For example, one communicator can speak and the other can type. We tested communicative effectiveness using accuracy and error detection in a trivia recall test, evaluating the roles of presentation and retrieval modalities on reporting facts stored in long-term memory. Heteromodal communication (hearing and writing or reading and saying) was more effective than homomodal communication (hearing and saying or reading and writing), with the most correct responses and the most errors caught. This has direct connections to communicative success and applied tests of skill.     

Very Long-term Recall in Infants: Infantile Amnesia Reconsidered

Abstract

Subjects who had participated in a study on non-verbal recall before their first birthday returned to the laboratory one year later and were tested for recall of their previous visit. During their previous visit they had shown recall of both familiar and novel actions on a set of novel objects. However, after a year's delay, evidence for recall was found for the familiar actions only. One action in particular was responsible for this finding: feeding a teddy bear with a schematic bottle. The majority of the returning subjects who had been shown this action repeated it after a year, whereas none of the other returning subjects and few of the subjects in the control groups performed this action. The results indicate that young infants have the ability to recall an event both at 11 months of age and after a delay as long as one year. The finding that infants can recall during a period that later becomes inaccessible to memory is important to our understanding of infantile amnesia.     

Reality monitoring of performed and imagined interactive events: developmental and contextual effects

Age differences in reality monitoring of interactive events were examined among 4-year-olds, 8-year-olds, 12-year-olds, and adults. Participants engaged in some interactions and imagined others. Afterward, they were asked to determine whether each action was performed, imagined, or new. This memory test was repeated 1 week later. The 4-year-olds had more difficulty discriminating imagined actions than the two oldest age groups. Imagined actions were more often confused with performed ones than the reverse, though this bias was significant only for the two younger age groups. Reality monitoring decreased over time, especially for imagined items. Activities in which the participant was the agent of action were discriminated better than those in which someone else was the agent of action. Object use during the activity increased the discrimination of imagined actions, especially after the delay. Similarity among actions had no effect. Implications for child eyewitness testimony are discussed.     

Reducing the Negative Effect of the Retention Interval on the Composite Face Recognition

Our memories are quite fragile. We sometimes recognize something unseen as something seen before. This error often causes serious problems, such as the misidentification of composite faces in a criminal investigation. In such a scene, people occasionally claim to have seen a face that is actually a composite face consisting of facial parts separately seen before; this error is called the memory conjunction error. Although the likelihood of the memory conjunction error increases over time, previous studies suggest that it could be suppressed by the number of response options, which are expected to affect the criterion for the “Old” response. Our results show that the presence of three response options reduced the memory conjunction error. Additionally, providing information about the existence of composite faces affected the sensitivity for detecting old faces, whereas three response options affected the criterion. This study might contribute to the improvement of procedures for eyewitness testimony.     

Embodied grounding of memory: Toward the effects of motor execution on memory consolidation

Behavioural and neuroscientific research has provided evidence for a strong functional link between the neural motor system and lexical–semantic processing of action-related language. It remains unclear, however, whether the impact of motor actions is restricted to online language comprehension or whether sensorimotor codes are also important in the formation and consolidation of persisting memory representations of the word's referents. The current study now demonstrates that recognition performance for action words is modulated by motor actions performed during the retention interval. Specifically, participants were required to learn words denoting objects that were associated with either a pressing or a twisting action (e.g., piano, screwdriver) and words that were not associated to actions. During a 6–8-minute retention phase, participants performed an intervening task that required the execution of pressing or twisting responses. A subsequent recognition task revealed a better memory for words that denoted objects for which the functional use was congruent with the action performed during the retention interval (e.g., pepper mill–twisting action, doorbell–pressing action) than for words that denoted objects for which the functional use was incongruent. In further experiments, we were able to generalize this effect of selective memory enhancement of words by performing congruent motor actions to an implicit perceptual (Experiment 2) and implicit semantic memory test (Experiment 3). Our findings suggest that a reactivation of motor codes affects the process of memory consolidation and emphasizes therefore the important role of sensorimotor codes in establishing enduring semantic representations.