Aging and memory for dreams.

This study investigated the influence of aging on memory for home drams and the extent to which cognitive variables such as visual memory, visuospatial IQ, and verbal IQ could account for possible differences herein. Subjects were 80 men and women of ages 45 to 75 years. Memory for dreams was measured by narrative length and frequency of recall. With respect to both measures no significant age differences were noted. Over-all differences in dream recall seemed best explained by visual memory scores. Partial correlational analyses, however, indicated that the small age differences memory or on any of the other cognitive variables. Dream contents were scored for aggression, friendliness, emotion, activities, and the number of characters and objects. The incidence of emotions among women appeared to be lower beyond the age of 60. Comparisons with previous data for young adults indicated that large reductions in aggression, friendliness, and emotion occur before the age of 45.     

Aging and memory for new associations: direct versus indirect measures.

Three experiments examined adult age differences in memory for new associations between unrelated words. On the indirect (word-stem completion) test, age differences appeared under the less-than-optimal study conditions of Experiments 1 and 3 but not under the self-paced study conditions of Experiment 2. In contrast, all experiments revealed significant age-related deficits on the direct tests, even those (word-stem cued recall) in which the cue was identical to those provided on the indirect test. The findings show that although age-related deficits in memory for new associations are particularly pronounced on tests requiring conscious recollection, age differences are not limited to such tests. Age deficits on both direct and indirect tests are related to the precision of elaborations produced during study. Similarities and differences between normal aging and amnesia are discussed, as are functional dissociations between direct and indirect measures.     

Aging and stereotype suppression

Recent work in social cognitive aging has suggested that older adults are more likely than younger adults to activate and use stereotypic information, even when they intend not to. Furthermore, evidence suggests that older adults have difficulty altering their interpretation of a situation, even when it has become clear that their initial interpretation is incorrect. In the current study, younger and older adults read a series of narratives in which a character had a sex-stereotyped occupation (e.g., a plumber is stereotypically male), and the character's gender was either consistent or inconsistent with that stereotype. Explicit labeling of gender was also varied. Results revealed that with explicit labeling, older adults were able to discount their stereotypes and avoid processing difficulties when subsequent stereotype-inconsistent information was encountered. These data suggest that when counter-stereotypic information is explicitly provided at encoding, older adults are no more likely than younger adults to rely on stereotypes, and are similarly capable of altering their interpretation of a situation when information suggests that interpretation is incorrect. These findings indicate that although older adults are more prone to the influence of unwanted stereotypes, this effect can be averted and judgments can be made more egalitarian by providing older adults with explicit stereotype contradiction at encoding.     

Visual working memory supports the inhibition of previously processed information: evidence from preview search

In four experiments we assessed whether visual working memory (VWM) maintains a record of previously processed visual information, allowing old information to be inhibited, and new information to be prioritized. Specifically, we evaluated whether VWM contributes to the inhibition (i.e., visual marking) of previewed distractors in a preview search. We evaluated this proposal by testing three predictions. First, Experiments 1 and 2 demonstrate that preview inhibition is more effective when the number of previewed distractors is below VWM capacity than above; an effect that can only be observed at small preview set sizes (Experiment 2A) and when observers are allowed to move their eyes freely (Experiment 2B). Second, Experiment 3 shows that, when quantified as the number of inhibited distractors, the magnitude of the preview effect is stable across different search difficulties. Third, Experiment 4 demonstrates that individual differences in preview inhibition are correlated with individual differences in VWM capacity. These findings provide converging evidence that VWM supports the inhibition of previewed distractors. More generally, these findings demonstrate how VWM contributes to the efficiency of human visual information processing--VWM prioritizes new information by inhibiting old information from being reselected for attention.     

Greater priming for previously distracting information in young than older adults when suppression is ruled out

The use of previously distracting information on memory tests with indirect instructions is usually age-equivalent, while young adults typically show greater explicit memory for such information. This could reflect qualitatively distinct initial processing (encoding) of distracting information by younger and older adults, but could also be caused by greater suppression of such information by younger adults on tasks with indirect instructions. In Experiment 1, young and older adults read stories containing distracting words, which they ignored, before studying a list of words containing previously distracting items for a free recall task. Half the participants were informed of the presence of previously distracting items in the study list prior to recall (direct instruction), and half were not (indirect instruction). Recall of previously distracting words was age-equivalent in the indirect condition, but young adults recalled more distracting words in the direct condition. In Experiment 2, participants performed the continuous identification with recognition task, which captures a measure of perceptual priming and recognition on each trial, and is immune to suppression. Priming and recognition of previously distracting words was greater in younger than older adults, suggesting that the young engage in more successful suppression of previously distracting information on tasks in which its relevance is not overtly signaled.     

Aging and memory for pictures of faces

The hypothesis that pictorial aspects of face-recognition memory are lower in old age was tested in 2 studies. Young and elderly Ss viewed 48 face pictures, and then took a test containing identical copies of input faces, pictorially changed versions of input faces, and entirely new faces. Replicating prior findings, Experiment 1 showed that false recognitions of entirely new faces were higher among elderly Ss. However, there were no age differences in distinguishing identical from pictorially changed faces. Using a modified test, Experiment 2 showed that although the elderly Ss had good knowledge that changed faces were changed, they had relatively poor knowledge of how they were changed. There appears to be age differences in analytical matching of pictorial information against information in memory.     

Aging and interference in verbal working memory.

According to inhibitory views of working memory, old adults should have particular problems deleting irrelevant information from working memory, leading to greater interference effects compared with young adults. The authors investigated this hypothesis by using variations of an A-B, C-D retroactive interference paradigm in working memory with young and old adults. They used a recognition measure of memory, assessing both accuracy and reaction time. The primary finding was that senior adults consistently exhibited proportionally greater retroactive interference effects compared with young adults when interfering word pairs that had been read aloud had to be rejected. Patterns of recognition and reaction time data suggested that old adults' activation of target material is similar to young adults, but they experience sustained activation of irrelevant material that has entered working memory. Theoretical implications of these findings for inhibitory deficit (R. T. Zacks & L. Hasher, 1998) and source memory deficit accounts of cognitive aging are discussed.     

Aging and memory for expected and unexpected objects in real-world settings.

Adult age differences in the consistency effect were examined in 3 experiments. The consistency effect refers to items inconsistent with expectations being better remembered than items consistent with expectations. Younger and older adults walked into an office room and viewed objects that varied in their consistency with expectation. Immediate and delayed recognition tests on item information (i.e., distractors were defined by their semantic identity) revealed that both age groups recognized unexpected items better than expected items. However, when recognition of token information was requested (i.e., distractors were defined by their physical appearance), younger adults, in contrast to older adults, exhibited consistency effects. Also, under divided attention, young adults revealed the same pattern of data as did elderly adults under full attention. The results are discussed in terms of capacity-related differences in distinctive encoding.     

Aging and recognition memory for emotional words: A bias account

The present study investigated age-related differences in the locus of the emotional enhancement effect in recognition memory. Younger and older adults studied an emotion-heterogeneous list followed by a forced choice recognition memory test. Luce’s (1963) similarity choice model was used to assess whether emotional valence impacts memory sensitivity or response bias. Results revealed that the emotional enhancement effect in both age groups was due to a more liberal response bias for emotional words. However, the pattern of bias differed, with younger adults more willing to classify negative words as old and older adults more willing to classify positive words as old. The results challenge the conclusion that emotional words are more memorable than neutral words.     

To see and remember: visually specific information is retained in memory from previously attended objects in natural scenes

What is the nature of the representation formed during the viewing of natural scenes? We tested two competing hypotheses regarding the accumulation of visual information during scene viewing. The first holds that coherent visual representations disintegrate as soon as attention is withdrawn from an object and thus that the visual representation of a scene is exceedingly impoverished. The second holds that visual representations do not necessarily decay upon the withdrawal of attention, but instead can be accumulated in memory from previously attended regions. Target objects in line drawings of natural scenes were changed during a saccadic eye movement away from those objects. Three findings support the second hypothesis. First, changes to the visual form of target objects (token substitution) were successfully detected, as indicated by both explicit and implicit measures, even though the target object was not attended when the change occurred. Second, these detections were often delayed until well after the change. Third, changes to semantically inconsistent target objects were detected better than changes to semantically consistent objects.     

Ecologically relevant stimuli and color memory

Ecologically relevant stimuli were developed as an alternative to Munsell color chips. Colored pictures of familiar objects were used to study color memory. We investigated the typicality of color to particular objects. Contextually typical colors were remembered more accurately than atypical colors were. Moreover, this variable had a stronger effect on memory than focality did. We concluded that memory for ecologically relevant material is more impressed by a color's relation to experience than by its intrinsic properties.     

Context-dependent memory for meaningful material: information for students

Context-dependency effects on memory for lists of unrelated words have been shown more often with recall than with recognition. Context dependency for meaningful text material was examined using two standard academic testing techniques: short answer (recall) and multiple choice (recognition). Forty participants read an article in either silent or noisy conditions; their reading comprehension was assessed with both types of test under silent or noisy conditions. Both tests showed context-dependency effects in which performance was better in the matching conditions (silent study/silent test and noisy study/noisy test) than in the mismatching conditions (silent study/noisy test and noisy study/silent test). Context cues appear to be important in the retrieval of newly learned meaningful information. An academic application is that students may perform better on exams by studying in silence. Copyright © 1998 John Wiley & Sons, Ltd.     

Sleep and memory: reproduction of syntactic structures previously evoked within REM sleep-related reports.

7 subjects, aged 19 to 25 yr., who evoked syntactic verbal material in the report made after awakening during REM sleep, were asked to reproduce it a few minutes later. No big differences had been obsered between the two recalls; all recalled verbal materials, many sentences and kernel-sentences reappeared. These results indicate a good consolidation of the material obtained after awakening during REM sleep.     

Recognition memory for deducible information

Recent research in language comprehension indicates a constructive encoding process in which the linguistic input is transformed into some more general semantic structure which is stored. In attempting to characterize the nature of such structures, some conflicting findings have been observed for paragraphs which describe similar set-theoretic relations, linear orderings and set inclusions. While the linear ordering research supports the constructivist theory, the set inclusion work does not. The set inclusion studies, however, employed true-false tests and not the usual recognition tests. The present study investigated the processing of set inclusion paragraphs in a self-paced study/recognition test paradigm. Results supported the constructivist theory and were contrary to predictions based upon the previous set inclusion research. Subjects were unable to differentiate between presented information and unpresented deducible information. These results were discussed in terms of accuracy constraints of different tasks on memorial performance and a possible interaction of Type of Test by Universal Quantification.     

Infant memory for place information

The present studies were designed to examine the role of place cues in memory retrieval during early infancy. Three-month-old infants were trained to move a mobile by kicking. Two weeks later, memory retrieval was disrupted if they were reminded in a location or place different from where they had been trained, but not if they were reminded in the same place (Experiment 1A). The same result was obtained even though highly salient cues in their immediate visual surround remained unchanged during reminding (Experiments 1B and 1C). No disruption was seen, however, when retrieval was cued in a different place after only 1 day (Experiment 2). These findings unequivocally demonstrate that infants as young as 3 months encode incidental information about the place where an event occurs and suggest that early memories are buffered against retrieval in potentially inappropriate contexts over the long term.     

Order information in dichotic memory.

Three experiments were performed using a recognition probe procedure to test the subject's recognition of the order of two items from a dichotically presented list. In all three experiments subjects were unable to recognize simultaneous items as having been simultaneous unless the critical pair was the last pair in the list. In contrast, they were able to identify the order of items not originally presented simultaneously at better than a chance level. Performance did not differ as a function of whether the two critical items were presented to the same or different ears. The data were interpreted as indicating that subjects divide attention between competing inputs in the dichotic memory task and that the eary-by-ear order of report is a result of the format in which the items are stored.     

Aging, memory and visual search

Potential age-related differences in the memory processes that underlie visual search are examined in the present study. Using a dynamic, gaze-contingent search paradigm developed to assess memory for previously examined distractors, older adults demonstrated no memory deficit. Surprisingly, older adults made fewer refixations compared to their younger counterparts, indicating better memory for previously inspected objects. This improved memory was not the result of a speed-accuracy trade-off or larger Inhibition-of-Return effects for older than for younger adults. Additional analyses suggested that older adults may derive their benefit from finer spatial encoding of search items. These findings suggest that some of the memory processes that support visual search are relatively age invariant.     

Misleading postevent information and memory for events: arguments and evidence against memory impairment hypotheses

The claim that a person's memory for an event may be altered by information encountered after the event has been influential in shaping current conceptions of memory. The basis for the claim is a series of studies showing that subjects who are given false or misleading information about a previously witnessed event perform more poorly on tests of memory for the event than subjects who are not misled. In this article we argue that the available evidence does not imply that misleading postevent information impairs memory for the original event, because the procedure used in previous studies is inappropriate for assessing effects of misleading information on memory. We then introduce a more appropriate procedure and report six experiments using this procedure. We conclude from the results that misleading postevent information has no effect on memory for the original event. We then review several recent studies that seem to contradict this conclusion, showing that the studies do not pose problems for our position. Finally, we discuss the implications of our conclusions for broader issues concerning memory.