Aging and the misinformation effect: a neuropsychological analysis

Older adults' susceptibility to misinformation in an eyewitness memory paradigm was examined in two experiments. Experiment 1 showed that older adults are more susceptible to interfering misinformation than are younger adults on two different tests (old-new recognition and source monitoring). Experiment 2 examined the extent to which processes associated with frontal lobe functioning underlie older adults' source-monitoring difficulties. Older adults with lower frontal-lobe-functioning scores on neuropsychological tests were particularly susceptible to false memories in the misinformation paradigm. The authors' results agree with data from other false memory paradigms that show greater false recollections in older adults, especially in those who scored poorly on frontal tests. The results support a source-monitoring account of aging and illusory recollection.     

How focus at encoding affects children’s source monitoring

Retention of source information is enhanced by focus on speakers’ feelings about statements even though recognition is reduced for both adults and children. However, does any focus on another person lead to enhanced source monitoring, or is a particular kind of focus required? Does other-focus enhance source monitoring, or does self-focus detract from it? In Experiment 1, 4- and 6-year-olds watched two speakers make statements in a no-focus control or with focus directed on how they (or a speaker) felt about the statements or on perceptual features about themselves (or the speaker). Source monitoring decisions were enhanced by other-focus in both the perceptual and emotional conditions. However, the effect was larger for the emotional condition, and source monitoring exceeded no-focus controls only for this condition. Experiment 2 showed no effect of other-focus versus self-focus on source monitoring when questions were semantic.     

Contributions of source and inhibitory mechanisms to age-related retroactive interference in verbal working memory

Determining contributions of source-monitoring and inhibitory function to age-related forgetting has been an elusive goal for cognitive theorists. Five studies used a verbal working memory paradigm to examine mechanisms accounting for disproportionate retroactive interference (RI) experienced with adult aging. Participants distinguished studied target-word pairs from interfering pairs that were read aloud. Source-monitoring and inhibitory task components varied through manipulations of response requirements. RI effects were primarily due to source-monitoring failures rather than to inhibitory failures. Removing both source and inhibitory components eliminated age differences in RI. When source monitoring was emphasized, RI continued to be observed in all age groups but disproportionately for older adults. Process dissociation analyses of memory found recollection decreases and familiarity increases consistent with source failures.     

Age-related differences in irrelevant-speech effects

Three experiments examined age-related differences in irrelevant-speech effects. Younger and older adults were required to recall short prose texts or lists of semantically related words presented visually together with distractor speech. In all experiments, older adults made more semantically related intrusion errors from the irrelevant speech than younger adults. Results of a source memory test suggested that these age-related differences in interference are most likely due to both inhibitory deficits and source-monitoring problems. The results lend partial support to the inhibition deficit theory of cognitive aging.     

Electrophysiological response during source memory decisions in older and younger adults

We recorded event-related potentials (ERPs) as individuals made source monitoring decisions in a paradigm in which the influence of item familiarity and goal relevance could be separately evaluated. Younger and older adults read a list of words and subsequently distinguished these words from foils in a running recognition test in which some foils were repeated after a lag of 6 items, creating familiar lures. Behaviorally, older and younger adults performed equally well in the recognition of study words and the rejection of singly presented foils. However, older adults were more likely to respond to the familiar lures as though they had come from the study list, thus producing the expected group difference in source-monitoring error. For younger adults the ERPs elicited by the targeted study words were maximal at posterior sites and significantly greater than those elicited by either familiar lures or foils. Older adults generated far less differentiated ERP waveforms but with a markedly greater amplitude at frontal sites. We interpret this frontal maximum in the context of poorer source monitoring as suggesting that older adults are more dependent on controlled processes to make discriminations that seem to occur much earlier and more automatically for younger adults.     

Aging and effect of predictability on reality monitoring

This study compared the direction of source confusions and the effect of predictability on reality monitoring for internally generated information and externally derived information in younger (mean age 19-25) and older (mean age 70-85) adults. Participants were invited to listen to the conclusions of simple stories or to generate and imagine them. Conclusions could be either highly predictable (Experiment 1) or unpredictable (Experiment 2). The change in predictability produced changes in the direction of source confusions only in older adults. When a story ended in a predictable way, older adults attributed to imagination conclusions that were actually perceived, whereas the pattern of confusions tended to reverse with unpredictable stories.     

Age differences in using source-relevant cues.

Subjects heard words originating from 2 speakers and later decided which of the 2 speakers said the words. Older adults had difficulty with source monitoring when perceptual cues from 2 sources were similar (2 female speakers), but this difficulty was overcome when perceptual cues were distinctive (a male and a female speaker) and were the only salient cues to source. Older adults also benefited from distinctive spatial cues when these were the only salient cues to source. Older adults, however, experienced difficulties in using multiple cues (both perceptual and spatial) to source effectively, whereas younger adults were able to use multiple cues to enhance their source-monitoring performance. It is suggested that age differences in source monitoring result from differential cue utilization.     

Unwanted Beliefs: Age Differences in Beliefs of False Information

Two experiments were conducted to test the Spinozan model of believing. Because of their reduced cognitive resources, older adults were predicted to be more likely than young adults to believe false information. Experiment 1 used a dispositional attribution paradigm to test this hypothesis. Young and older adults were exposed to both true and false (either positive or negative) trait information about the target persons. Participants then made dispositional ratings and evaluated the target persons on overall likeability scales. Results supported the Spinozan model of believing. Older adults were more likely than young adults to believe false information and their dispositional ratings were reliably biased by the valence of false information. Experiment 2 further examined whether these false beliefs of older adults were actually conscious beliefs. It was found that older adults consciously recollected the false statements as true and these false beliefs mediated age differences in dispositional attribution.     

Conjunction errors in recognition memory: modality-free errors for older adults but not for young adults

A dual-process theory of memory was applied to processes in normal aging, with a focus on recognition errors in the feature-conjunction paradigm (i.e., false recognition of blackbird after studying parent words blackmail and/or jailbird). Study repetition was manipulated so that some parent words occurred once and others occurred three times. Age-related differences on hit scores occurred for two experiments. The results for feature and conjunction conditions showed repetition effects but no age-related differences when participants were uninformed of the lures (Experiment 1). However, age-related differences emerged when the retrieval of modality source information created a way to evade conjunction errors (Experiment 2). In the second experiment, study repetition decreased errors for the young adults but increased errors for the older adults, and young adults were better able than older adults to avoid conjunction errors when the parent words had been repeated. For older adults, the conjunction errors were modality-free. The results provide additional evidence that older adults experience difficulty in recollecting aspects of a study experience, and the results from groups of young adults required to respond quickly on the tests provide converging evidence for this conclusion.     

Are older adults less efficient in making attributions about the origin of memories for web interaction?

IntroductionAs people age, they may be less likely to recollect where or when an event took place. However, few studies of source monitoring and aging have used tasks that are similar to what people do in everyday life.ObjectivePotential age-related differences in making attributions about the origin of remembered events in Web interaction are examined in the present study.MethodsA Web-based source-monitoring paradigm was modelled to assess both item and source memory, which incorporated typical Web search tasks.ResultsOlder adults exhibited a reduced ability in navigation-oriented search, where both a measure of processing speed and a measure of executive function were significant predictors of performance. They were less able to recognize and recollect items previously encountered in web pages. However, source memory was not more impaired with age than item memory. Interestingly, although the addition of cognitive operations as a cue to source had no impact on source memory, it resulted in increased recognition and recollection in the older adults.ConclusionMore generally, recognition and recollection appeared to be dissociated from source memory as a function of different individual difference measures.     

How eyewitnesses resist misinformation: Social postwarnings and the monitoring of memory characteristics

Previous findings have been equivocal as to whether the postevent misinformation effect on eyewitness memory is reduced by warnings presented after the misinformation (postwarnings). In the present research, social postwarnings, which characterize the postevent source as a low-credibility individual, diminished the misinformation effect in both cued recall and recognition tests. Discrediting the source as being either untrustworthy or incompetent was effective (Experiment 1). Also, postwarned participants rated reality characteristics of their memories more accurately than did participants receiving no or high-credibility information about the postevent source (Experiment 2). A social postwarning yielded the same results as an explicit source-monitoring appeal and led to longer response times for postevent items, relative to a no-warning condition (Experiments 3 and 4). The findings suggest that the reduced misinformation effect was due to more thorough monitoring of memory characteristics by postwarned participants, rather than to a stricter response criterion or to enhanced event memory.     

Age differences in collaborative memory: the role of retrieval manipulations

In two experiments, we examined age differences in collaborative inhibition (reduced recall in pairs of people, relative to pooled individuals) across repeated retrieval attempts. Younger and older adults studied categorized word lists and were then given two consecutive recall tests and a recognition test. On the first recall test, the subjects were given free-report cued recall or forced-report cued recall instructions (Experiment 1) or free recall instructions (Experiment 2) and recalled the lists either alone or in collaboration with another subject of the same age group. Free-report cued recall and free recall instructions warned the subjects not to guess, whereas forcedreport cued recall instructions required them to guess. Collaborative inhibition was obtained for both younger and older adults on initial tests of free-report cued recall, forced-report cued recall, and free recall, showing that the effect generalizes across several tests for both younger and older adults. Collaborative inhibition did not persist on subsequent individual recall or recognition tests for list items. Older adults consistently falsely recalled and recognized items more than did younger adults, as had been found in previous studies. In addition, prior collaboration may exaggerate older adults’ tendency toward higher false alarms on a subsequent recognition test, but only after a free recall test. The results provide generality to the phenomenon of collaborative inhibition and can be explained by invoking concepts of strategy disruption and source monitoring.     

Source monitoring and suggestibility to misinformation: adult age‐related differences

We compared young and older adults' source monitoring performance on an explicit source identification test using the misinformation paradigm. Several age‐related differences in source memory were demonstrated: (a) older adults were more likely than were young adults to say that they saw information that was actually only suggested to them; (b) older adults were more confident in their false memories than were young adults; (c) older adults were less confident in their accurate memory for the source of information than were young adults. Together, the data suggest that older adults either lacked or failed to use helpful diagnostic source information (e.g. perceptual details or temporal information), and that their confidence in their false memories reflected an over‐weighting of semantic information. Copyright © 2002 John Wiley & Sons, Ltd.     

The effect of forced recall on illusory recollection in younger and older adults

The effect of an initial forced recall test on later recall and recognition tests was examined in younger and older adults. Subjects were presented with categorized word lists and given an initial test under standard cued recall instructions (with a warning against guessing) or forced recall instructions (that required guessing); subjects were later given a cued recall test for the original list items. In 2 experiments, initial forced recall resulted in higher levels of illusory memories on subsequent tests (relative to initial cued recall), especially for older adults. Older adults were more likely to say they remembered rather than knew that forced guesses had occurred in the original study episode. The effect persisted despite a strong warning against making errors in Experiment 2. When a source monitoring test was given, older adults had more difficulty than younger adults in identifying the source of items they had originally produced as guesses. If conditions encourage subjects to guess on a first memory test, they are likely to recollect these guesses as actual memories on later tests. This effect is exaggerated in older adults, probably because of their greater source monitoring difficulties. Both dual process and source monitoring theories provide insight into these findings.     

The role of encoding in reality monitoring: a running memory test with Alzheimer's type dementia

Reality monitoring refers to the discrimination between memories of internal and external events (e.g., Johnson & Raye, 1981). A total of 28 healthy older adults and 28 older adults with Alzheimer's type dementia (DAT) were asked to perform or to imagine performing simple action statements in a running memory test. This task required participants to tell whether the action statement had been carried out or imagined, or whether it was new at unpredictable intervals. The results indicated that older adults with DAT had greater difficulty in reality monitoring than did the healthy control group. The finding is discussed in terms of the role of working memory functions in reality monitoring.     

The role of encoding in reality monitoring: A running memory test with Alzheimer's type dementia

Reality monitoring refers to the discrimination between memories of internal and external events (e.g., Johnson & Raye, 1981). A total of 28 healthy older adults and 28 older adults with Alzheimer's type dementia (DAT) were asked to perform or to imagine performing simple action statements in a running memory test. This task required participants to tell whether the action statement had been carried out or imagined, or whether it was new at unpredictable intervals. The results indicated that older adults with DAT had greater difficulty in reality monitoring than did the healthy control group. The finding is discussed in terms of the role of working memory functions in reality monitoring.     

Aging, source memory, and misrecollections

The authors propose an illusory recollection account of why cognitive aging is associated with episodic memory deficits. After listening to statements presented by either a female or a male speaker, older adults were prone to misrecollecting past events. The authors' illusory recollection account is instantiated in a new illusory recollection signal detection model that provides a better fit of older adults' data than does the standard signal detection model. They observed that age-related differences in source memory (as measured by source d' scores) virtually disappear after accounting for the occurrence of illusory recollections. These data suggest that age-related source memory impairments are not due to older adults' remembering less diagnostic source information and having to guess more. Instead, older adults appear to misremember past events more often than younger adults.