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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adults' memories of childhood: True and false reports.

In 3 experiments, the authors examined factors that, according to the source-monitoring framework, might influence false memory formation and true/false memory discernment. In Experiment 1, combined effects of warning and visualization on false childhood memory formation were examined, as were individual differences in true and false childhood memories. Combining warnings and visualization led to the lowest false memory and highest true memory. Several individual difference factors (e.g., parental fearful attachment style) predicted false recall. In addition, true and false childhood memories differed (e.g., in amount of information). Experiment 2 examined relations between Deese/Roediger-McDermott task performance and false childhood memories. Deese/Roediger-McDermott performance (e.g., intrusion of unrelated words in free recall) was associated with false childhood memory, suggesting liberal response criteria in source decisions as a common underlying mechanism. Experiment 3 investigated adults' abilities to discern true and false childhood memory reports (e.g., by detecting differences in amount of information as identified in Experiment 1). Adults who were particularly successful in discerning such reports indicated reliance on event plausibility. Overall, the source-monitoring framework provided a viable explanatory framework. Implications for theory and clinical and forensic interviews are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cross-modal source monitoring confusions between perceived and imagined events.

Two experiments tested the prediction based on the source monitoring framework that imagination is most likely to lead to false memories when related perceived events have occurred. Consistent with this, people were more likely to falsely remember seeing events when the events had been both imagined as seen and actually heard than when they were just heard, just visually imagined, or imagined both visually and auditorily. Furthermore, when people considered potential sources for memories or more carefully evaluated features of remembered events, source errors were reduced. On average, misattributed ("false") memories differed in phenomenal qualities from true memories. Taken together, these findings show that as different qualities of mental experience flexibly enter into source attributions, qualities derived from related perceptual events are particularly likely to lead to false claims that imagined events were seen, even when the event involves a primary modality (auditory) different from the target event (visual). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recognition memory in depression.

Research suggests that the poor performance of depressed patients on memory tests reflects cautious response criteria rather than reduced accessibility of memories. Studies of recognition memory enable this issue to be addressed. The present experiment provides the first clear demonstration of a deficit in recognition memory in depression that is not explicable in terms of response bias. A subsidiary concern was to examine the effect of requiring subjects to vocalize words on presentation. This had no significant effects on "hits," but it interacted with depression on "false alarms," suggesting that discrepant claims in the literature regarding the effects of depression on false alarms may be attributable to procedural variations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Qualitative effects of rehearsal on memories for perceived and imagined complex events.

Three experiments explored the effects of rehearsal and the passage of time on qualitative characteristics of memories for perceived and imagined complex events. Subjects thought or talked about events, focusing on either the perceptual (e.g., colors, sounds) or apperceptive (e.g., thoughts, feelings) aspects of the events (Experiment 1). Thinking about apperceptive aspects of events decreased the salience of context and sensory characteristics of memories and made memories for perceived and imagined events seem more similar in the subjective amounts of thoughts and feelings included in the memories. When the aspects of events subjects thought about were unspecified, thinking about events primarily affected rated clarity (Experiment 2). The clarity of imagined events was more affected than was the clarity of perceived events by whether the memories had been rated previously (Experiments 1 & 3). Over 24 hrs, clarity and sensory ratings decreased more for imagined than for perceived events (Experiment 3). Implications for reality monitoring (M. K. Johnson and C. L. Raye [see PA, Vol 65:6694]) are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comments on "Measuring memory for source: Some theoretical assumptions and technical limitations"

Three studies showed that information used in determining a target memory's source may be derived not only from the target event itself, but also from other nontarget events or memories. Subjects were more likely to claim that an imagined object was perceived when it physically resembled or was conceptually related to another specific item that was actually perceived, relative to when there was no physical resemblance or semantic relation. Furthermore, error rates for imagined items increased with the number of perceived items that they resembled. However, subjects' orienting task at encoding (perceptually biased or perceptually plus conceptually biased) did not systematically affect error rates. The results indicate that reality monitoring decisions about a target object are influenced by similar physical and conceptual information that was derived from other objects.     

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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related binding deficits and the content of false memories.

The authors examined effects of age-related binding deficits on feature information in false memories for imagined objects (e.g., lollipop) that were similar in shape to seen objects (e.g., magnifying glass). In Experiment 1, location memory for seen objects was lower in older than younger adults and lower still in old-old than young-old adults. Imagined objects, when falsely called seen, were less likely to be attributed to the location of similar seen objects (i.e., congruent attributions) by old-old than young-old adults. In Experiment 2, for younger adults, displaying seen objects for less time (1 s vs. 4 s) reduced both location memory for seen objects and congruent attributions for false memories. Thus, binding deficits may influence the specific content of false memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adaptive memory: Survival processing increases both true and false memory in adults and children.

Research has shown that processing information in a survival context can enhance the information's memorability. The current study examined whether survival processing can also decrease the susceptibility to false memories and whether the survival advantage can be found in children. In Experiment 1, adults rated semantically related words in a survival, moving, or pleasantness scenario. Even though the survival advantage was demonstrated for true recall, there also was an unexpected increase in false memories in the survival condition. Similarly, younger and older children in Experiment 2 displayed superior true recall but also higher rates of false memories in a survival condition. Experiment 3 showed that in adults false memories were also more likely to occur in the survival condition when categorized lists instead of Deese-Roediger-McDermott (DRM)-like word lists were used. In all three experiments, no survival recall advantage was found when net accuracy scores that take the total output into account were used. These findings question whether survival processing is an adaptive memory strategy per se, as such processing not only enriches true recall but simultaneously amplifies the vulnerability to false memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phenomenal characteristics of memories for perceived and imagined autobiographical events.

Two studies explored potential bases for reality monitoring (M. K. Johnson and C. L. Raye [see PA, Vol 65:6694]) of naturally occurring autobiographical events. In Study 1, subjects rated phenomenal characteristics of recent and childhood memories. Compared with imagined events, perceived events were given higher ratings on several characteristics, including perceptual information, contextual information, and supporting memories. This was especially true for recent memories. In Study 2, subjects described how they knew autobiographical events had (or had not) happened. For perceived events, subjects were likely to mention perceptual and contextual details of the memory and to refer to other supporting memories. For imagined events, subjects were likely to engage in reasoning based on prior knowledge. The results are consistent with the idea that reality monitoring draws on differences in qualitative characteristics of memories for perceived and imagined events (Johnson & Raye, 1981) and augment findings from more controlled laboratory studies of complex events (A. G. Suengas and M. K. Johnson [see PA, Vol 76:14478]; M. K. Johnson and A. G. Suengas, in press). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Investigating strength and frequency effects in recognition memory using type-2 signal detection theory.

Criterion- versus distribution-shift accounts of frequency and strength effects in recognition memory were investigated with Type-2 signal detection receiver operating characteristic (ROC) analysis, which provides a measure of metacognitive monitoring. Experiment 1 demonstrated a frequency-based mirror effect, with a higher hit rate and lower false alarm rate, for low frequency words compared with high frequency words. In Experiment 2, the authors manipulated item strength with repetition, which showed an increased hit rate but no effect on the false alarm rate. Whereas Type-1 indices were ambiguous as to whether these effects were based on a criterion- or distribution-shift model, the two models predict opposite effects on Type-2 distractor monitoring under some assumptions. Hence, Type-2 ROC analysis discriminated between potential models of recognition that could not be discriminated using Type-1 indices alone. In Experiment 3, the authors manipulated Type-1 response bias by varying the number of old versus new response categories to confirm the assumptions made in Experiments 1 and 2. The authors conclude that Type-2 analyses are a useful tool for investigating recognition memory when used in conjunction with more traditional Type-1 analyses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sensitivity reductions in false recognition: A measure of false memories with stronger theoretical implications.

Signal detection analyses of recognition memory indicate that a bias to respond "old" is large for critical words that are centrally related with previously encoded word lists, is small for words that are less related, and is not observed for unrelated words. Also, recognition sensitivity has not been previously shown to differ between those conditions, which has focused debate over how to explain false recognition on the bias differences. In 3 experiments, critical-word sensitivity was lower than sensitivity for other word types, but related-word sensitivity was not lower than sensitivity for unrelated words. Extant models that predict reduced critical-word sensitivity also predict lower sensitivity for related words than for unrelated words. These results provide crucial new constraints on theoretical explanations of false memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Children's and adults' spontaneous false memories: long-term persistence and mere-testing effects

In studies of children's false memories of word lists, it has been found that false alarms are stable over long-term retention intervals (persistence effect), that the stability of false alarms can equal or exceed that of hits, that earlier memory tests increase the frequency of hits on later tests (true-memory inoculation effect), that earlier memory tests increase the frequency of false alarms on later tests (false-memory creation effect), and that test-induced increases in false alarms can equal or exceed increases for hits. We studied these phenomena in 6-, 8-, and 11-year-olds and in adults using short narratives about everyday objects and events. All of the phenomena were detected at all ages, but levels of spontaneous memory falsification were much higher than for word lists and patterns of developmental change were somewhat different. Important new findings were that the persistence effect and the false-memory creation effect were greatest for statements that would be regarded as factually incorrect reports of events in sworn testimony and that, like suggestive questioning, interviews that involve nonsuggestive recognition questions may nevertheless taint children's memories.     

Time-course studies of reality monitoring and recognition.

Two studies used a response–signal procedure to explore the time course of source-monitoring judgments about perceived and imagined events. Ss judged whether probe words corresponded to pictures that had previously been seen or imagined or were new. Old–new recognition accuracy grew to significant levels before reality-monitoring accuracy, supporting the notion that source monitoring requires more of or a different type of information that does old–new recognition. Also, source identification accuracy developed more quickly for imagined items than for perceived items. This difference in time-course functions is consistent with the idea that memories for perceived and imagined events differ in the relative amounts of various types of information they include (M. K. Johnson and C. L. Raye; see record 1981-06694-001) and that these different types of information may revive or become available to source attribution mechanisms at different rates or may be differentially salient during reality monitoring. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mere memory testing creates false memories in children.

It has been reported that initial recall tests inoculate true memories against forgetting without creating false memories. This is not true of recognition tests. In 2 experiments with 5- and 8-year-olds, initial recognition tests elevated children's false-memory responses (false alarms to unpresented distractors) on delayed tests. In Experiment 1, false-memory creation exceeded true-memory inoculation in 5-year-olds, producing net losses in accuracy over time. In Experiment 2, false-memory creation exceeded true-memory inoculation at both age levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Features and feedback: Enhancing metamnemonic knowledge at retrieval reduces source-monitoring errors.

Three experiments explored the issue of whether enhanced metamnemonic knowledge at retrieval can improve participants' ability to make difficult source discriminations in the context of the eyewitness suggestibility paradigm. The 1st experiment documented differences in phenomenal experience between veridical and false memories. Experiment 2 revealed that drawing participants' attention to these differences by pairing the ratings of the features with instructions about their utility was successful in reducing source misattributions of suggested items to the event. The results of Experiment 3 showed that participants can make online adjustments in the types of evidence used to make source judgments, as participants who received correct feedback during the training portion of the test reduced misattribution errors on the remainder of the test where feedback was not provided. Altogether, these studies suggest that people can discover and benefit from updated knowledge of the types of memorial evidence that discriminate between sources of information in memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysis of thermal stability of soya globulins using monoclonal antibodies

Previous research on spatial memory indicated that memories of small layouts were orientation dependent (orientation specific) but that memories of large layouts were orientation independent (orientation free). Two experiments investigated the relation between layout size and orientation dependency. Participants learned a small or a large 4-point path (Experiment 1) or a large display of objects (Experiment 2) and then made judgments of relative direction from imagined headings that were either the same as or different from the single studied orientation. Judgments were faster and more accurate when the imagined heading was the same as the studied orientation (i.e., aligned) than when the imagined heading differed from the studied orientation (i.e., misaligned). This alignment effect was present for both small and large layouts. These results indicate that location is encoded in an orientation-dependent manner regardless of layout size.     

True memory, false memory, and subjective recollection deficits after focal parietal lobe lesions.

Objective: There is mounting evidence that the posterior parietal cortex (PPC) plays an important role in episodic memory. We previously found that patients with PPC damage exhibit retrieval-related episodic memory deficits. Here we assess whether parietal lobe damage affects episodic memory on a different task: the Deese–Roediger–McDermott (DRM) false-memory paradigm. Methods: Two patients with bilateral PPC damage and a group of matched controls were tested. In Experiment 1, the task was to remember words; in Experiment 2 the task was to remember pictures of common objects. Prior studies have shown that normal participants have high levels of false memory to words, low levels to pictures. Results: The patients exhibited significantly lower levels of false memory to words. One patient showed significantly elevated levels of false memory to pictures. The patients' false memories were accompanied by reduced levels of recollection, as tested by a Remember/Know procedure. Conclusions: PPC damage causes decreased levels of false memories and an abnormal Remember/Know profile. Their false memory rate is similar to the rate exhibited by patients with medial temporal lobe damage. These results support the view that portions of the PPC play a critical role in objective and subjective aspects of recollection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mental representations of large and small spatial layouts are orientation dependent.

Previous research on spatial memory indicated that memories of small layouts were orientation dependent (orientation specific) but that memories of large layouts were orientation independent (orientation free). Two experiments investigated the relation between layout size and orientation dependency. Participants learned a small or a large 4-point path (Experiment 1) or a large display of objects (Experiment 2) and then made judgments of relative direction from imagined headings that were either the same as or different from the single studied orientation. Judgments were faster and more accurate when the imagined heading was the same as the studied orientation (i.e., aligned) than when the imagined heading differed from the studied orientation (i.e., misaligned). This alignment effect was present for both small and large layouts. These results indicate that location is encoded in an orientation-dependent manner regardless of layout size. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Biased recognition of positive faces in aging and amnestic mild cognitive impairment.

We investigated age differences in biased recognition of happy, neutral, or angry faces in 4 experiments. Experiment 1 revealed increased true and false recognition for happy faces in older adults, which persisted even when changing each face’s emotional expression from study to test in Experiment 2. In Experiment 3, we examined the influence of reduced memory capacity on the positivity-induced recognition bias, which showed the absence of emotion-induced memory enhancement but a preserved recognition bias for positive faces in patients with amnestic mild cognitive impairment compared with older adults with normal memory performance. In Experiment 4, we used semantic differentials to measure the connotations of happy and angry faces. Younger and older participants regarded happy faces as more familiar than angry faces, but the older group showed a larger recognition bias for happy faces. This finding indicates that older adults use a gist-based memory strategy based on a semantic association between positive emotion and familiarity. Moreover, older adults’ judgments of valence were more positive for both angry and happy faces, supporting the hypothesis of socioemotional selectivity. We propose that the positivity-induced recognition bias might be based on fluency, which in turn is based on both positivity-oriented emotional goals and on preexisting semantic associations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)