Studies of directed forgetting in older adults

Younger and older adults were compared in 4 directed forgetting experiments. These varied in the use of categorized versus unrelated word lists and in the use of item by item versus blocked remember-forget cueing procedures. Consistent with L. Hasher and R. T. Zacks's (1988) hypothesis of impaired inhibitory mechanisms in older adults, a variety of findings indicated that this age group is less able than younger adults to suppress the processing and retrieval of items designated as to be forgotten (TBF). Specifically, in comparison with younger adults, older adults produced more TBF word intrusions on an immediate recall test (Experiments 1A and 1B), took longer to reject TBF items (relative to a neutral baseline) on an immediate recognition test (Experiment 3), and recalled (Experiments 1A, 1B, and 2) and recognized (Experiment 1B and 2) relatively more TBF items on delayed retention tests in which all studied items were designated as targets.     

Aging and memory for words and action events: Effects of item repetition and list length.

We were concerned with the effects of item repetition, list length, and class of item on free recall in elderly as compared with young adults. In Experiment 1, samples of young and elderly adults recalled a list of 27 words and a list of 27 action events (minitasks performed by the subjects). Some items were presented once and some twice. Although the younger subjects showed better recall on both types of lists, the older sample benefited from item repetition as much as did the younger sample. This finding was replicated in Experiment 2. A second finding in Experiment 2 was a significant aging effect in the recall of long but not of short lists of both words and action events. The absence of an Age?×?Repetition Effect interaction was ascribed to the strength nature of the repetition manipulation. The age effects in the recall of the long lists were attributed to possible deficits in retrieval proficiency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Maximizing the benefits and minimizing the costs of repeated memory tests for older adults.

Repeatedly trying to remember information can help people remember more but can also lead to inaccuracies. Two experiments examined whether the costs of repeated recall efforts can be minimized for older adults by using memory tests that require specification of the source of recalled items. Participants saw and imagined pictures and then took 3 successive recall tests in which they either indicated the source of each remembered item (source recall) or simply recalled the items without specification of their source (free recall). Results showed that recall increased systematically from Test 1 to Test 3, although the rate of increase was less marked for older adults, and older adults recalled less overall. After the free recall tests, older adults made more source misattributions (claiming to have seen imagined items) than did young adults, but after the source recall tests, age differences were not significant. Thus, repeatedly recalling items while considering their source was associated with benefits in terms of increased recall and fewer costs in terms of source errors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

False Memories: Young and Older Adults Think of Semantic Associates at the Same Rate, but Young Adults Are More Successful at Source Monitoring.

Two experiments explored whether the higher vulnerability to false memories in the DRM (J. Deese, 1959; H. L. Roediger & K. B. McDermott, 1995) paradigm in older compared to young adults reflects a deficit in source monitoring. In both experiments, adding together the number of falsely recalled critical lures and the number of critical lures produced on a post-recall test asking participants to report items that they had thought of but did not recall, indicated that the critical lures were activated during the experiment equally often in young and older adults. However, older adults were more likely than young adults to say that they had actually heard the lures. When strongly encouraged to examine the origin of memories (Experiment 2), the warning substantially reduced false recall in young but not older adults. These results are consistent with the idea that older adults have more difficulty later identifying the source of information that was activated as a consequence of intact semantic activation processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Distraction by competing speech in young and older adult listeners.

In 2 experiments, young and older adults heard target speech presented in quiet or with a competing speaker in the background. The distractor consisted either of meaningful speech or nonmeaningful speech composed of randomly ordered word strings (Experiment 1) or speech in an unfamiliar language (Experiment 2). Tests of recall for the target speech showed that older adults, but not younger adults, were impaired more by meaningful distractors than by nonmeaningful distracters, However, on a surprise recognition test, young adults were more likely than older adults to recognize meaningful distractor items. These results suggest that reduced efficiency in attentional control is an important factor in older adults' difficulty in recalling target speech in the presence of a background of competing speech. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adult age differences in memory for prose: The question of sensitivity to passage structure.

The hypothesis that older adults remember prose less well than young adults because they are less sensitive to the structure of prose passages was investigated in three experiments. In Experiments 1 and 2, older adults (aged 54–85) recalled less information than younger ones (aged 20–36) from stories having various structures, but there was no evidence that older people were insensitive to story structure. The pattern of recall of information high and low in the story structure was similar for young and old for each story examined. Experiment 3 extended the findings to recall of full-length essays and their summaries. These results suggest that the old are as sensitive to passage structure as the young. In addition, comparisons across the three experiments suggest that other frequently invoked explanations of age deficits in prose recall, such as individual differences in verbal ability and the nature of the materials used, cannot explain our results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related equivalence of identity suppression in the Stroop color-word task.

Previous failures to find reliable identity suppression (identity negative priming) in older adults have led to conclusions that older adults suffer from an impairment in the inhibitory component of selective attention. Here, 2 experiments using the Stroop procedure found identity suppression in older adults that was both reliable and equivalent to that in younger adults. Experiment 1 with repeated target colors produced correlations consistent with an episodic retrieval explanation of identity suppression, Experiment 2 without repeated targets produced correlations inconsistent with the episodic retrieval interpretation. These patterns were found for both younger and older adults. No evidence was found for reduced identity suppression that would be consistent with a general inhibitory impairment in older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Processing relational and item-specific information: Effects of aging and division of attention.

64 young adults (aged 18–21 yrs) and 32 older Ss (aged 65–83 yrs) encoded items from categorizable lists under incidental learning conditions. Two orienting tasks were used: a category sorting task and a pleasantness rating task. The number of items/category was varied (between 2 and 14) within each list. In addition, 24 young adults performed the orienting tasks while simultaneously engaged in an attention-demanding secondary task (divided-attention condition). Recall declined with both age and division of attention, while recall clustering was greatest for the older Ss and least for the young divided-attention Ss. The effects of category size and orienting task on recall did not vary across groups. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Use of relational and item-specific information in remembering by older and younger adults.

The applicability to older adults of predictions from the integrated memory model, that optimal memory results from concurrent availability of relational and item-specific information, was assessed. In Experiment 1, older adults (M?=?69 years) encoded related or unrelated words using rating, sorting, or both tasks. Using both tasks produced better recall than either separate task. Rating facilitated recall for related items, but sorting did not facilitate unrelated items. In Experiment 2, younger (M?=?20) and older (M?=?74) adults sorted or rated lists comprising categories of varying sizes. Young adults' free recall conformed to predictions, but older adults again showed facilitation mainly from rating larger categories. The stronger effects for younger adults imply that specific combinations of encoding and retrieval manipulations and materials must be considered in predicting older adults' performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging, hearing acuity, and the attentional costs of effortful listening.

A dual-task interference paradigm was used to investigate the effect of perceptual effort on recall of spoken word lists by young and older adults with good hearing and with mild-to-moderate hearing loss. In addition to poorer recall accuracy, listeners with hearing loss, especially older adults, showed larger secondary task costs while recalling the word lists even though the stimuli were presented at a sound intensity that allowed correct word identification. Findings support the hypothesis that extra effort at the sensory–perceptual level attendant to hearing loss has negative consequences to downstream recall, an effect that may be further magnified with increased age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An auditory repetition deficit under low memory load.

Previous studies of the auditory analogue of repetition blindness have led to different conclusions regarding the nature of the effect (e.g., N. Kanwisher & M. C. Potter, 1989; M. Miller & D. MacKay, 1994). In the present study, recall accuracy for repeated elements was examined with lists of 2 or 3 items presented dichotically under high temporal pressure. When this procedure was used, a repetition deficit in recall was obtained for both vowels (Experiment 1) and consonant-vowel syllables (Experiment 2). Further experiments demonstrated that this deficit decreases as the stimulus onset asynchrony between the 2 critical elements increases (Experiment 3) and showed that the effect also occurs for words and not just nonsense syllables (Experiment 4). In all 4 experiments, estimations of guessing biases showed that responses to unrepeated lists were not artificially favored over responses to repeated lists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Part-Set Cuing Effects in Younger and Older Adults.

In 3 experiments, the authors examined part-set cuing effects in younger and older adults. Participants heard lists of category exemplars and later recalled them. Recall was uncued or cued with a subset of studied items. In Experiment 1, participants were cued with some of the category names, and they remembered fewer never-cued categories than a free-recall condition. In Experiment 2, a similar effect was observed for category exemplar cues. There was also an age difference: By some measures, a small number of cues impaired older adults more than younger. Experiment 3 replicated this result and found that older adults were disproportionately slow in the presence of cues. Across experiments, older adults showed robust part-set cuing effects, and sometimes, they were disproportionately impaired by cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Repetition priming of nonwords in young and older adults.

In 3 experiments, a pronunciation task was used to examine repetition priming of novel nonwords in young and older adults. The contributions of item and associative priming to the total repetition priming effect were assessed. In Experiment 1, age consistency was found in both components of repetition priming after 9 repetitions of nonwords. Experiment 2 established that young and older adults were similar in item and associative priming after as few as 2 repetitions of nonwords. Finally, Experiment 3 demonstrated that associative priming persists for at least 3 min and that it is dissociable from cued recall. The overall pattern of results strongly argues that elaborative processing is not necessary to obtain associative priming in indirect memory tasks and that young and older adults show similar magnitudes of associative priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences and similarities in the shift from computation to retrieval during reading comprehension.

Previous research has established that 1 mechanism underlying speed-ups in task performance with practice involves a shift from computational processing to retrieval of information encoded earlier in practice. To what extent do young and older adults differ in shifts from computation to retrieval with practice in reading comprehension? Young and older adults read short stories containing an unfamiliar noun–noun combination (e.g., bee caterpillar) followed by disambiguating information indicating the combination’s meaning (either the normatively dominant meaning or an alternative subordinate meaning). Stories were presented either once or repeatedly across practice blocks. In Experiment 1, both age groups shifted from computation to retrieval with practice for the repeated items. However, older adults were slower to shift (e.g., older adults showed slower convergence of reading times for repeated subordinate and dominant items). Results of Experiment 2 suggested that the slower shift was due to age differences in bias against using retrieval rather than associative learning differences. The authors compare age differences in retrieval shifts in reading versus other tasks and discuss implications for age differences in the regulation of reading comprehension. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Immediate serial recall of mixed-modality lists.

Seven experiments are reported in which subjects were tested for immediate serial recall of mixed-modality lists. On mixed auditory-visual lists, there was an advantage for auditory items at all serial positions. This was due to both a facilitation of auditory items and an inhibition of visual items on mixed lists, as compared with single-modality lists. When presented on a list containing items read silently, recall of items that were silently mouthed by the subject demonstrated patterns similar to those found with auditory items. When presented on a list containing items read aloud, recall of mouthed items showed patterns similar to those found with silently read items. The auditory advantage on mixed lists was found even when the list items were acoustically similar or identical and was not reduced by midlist auditory suffixes. The results suggest that modality differences in recall of mixed-modality lists are based on information different from that responsible for modality differences in recall of single-modality lists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in item manipulation span: The case of letter-number sequencing.

The authors report 2 experiments in which they examined age differences in working memory tasks involving complex item manipulation (i.e., letter-number sequencing). In Experiment 1, age differences on tasks involving item manipulation were not greater than age differences on tasks requiring recall of items in the order in which they appeared, suggesting that older adults do not have difficulty with item manipulation per se. In Experiment 2, slower presentation rates increased age differences in item manipulation spans, although age differences at the fastest rate may be attributed to differences in strategy use. In both experiments, age differences were largest when participants were most likely to be remembering familiar sequences, suggesting that older adults may have difficulties dampening the representations of such sequences once they are activated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparing the effects of aging and background noise of short-term memory performance.

Paired associate recall was tested as a function of serial position for younger and older adults for five word pairs presented aurally in quiet and in noise. In Experiment 1, the addition of noise adversely affected recall in young adults, but only in the early serial positions. Experiments 2 and 3 suggested that the recall of older adults listening to the words in quiet was nearly equivalent to that of younger adults listening in noise. In Experiment 4, we determined the signal-to-noise ratio (S/N) such that, on average, younger and older adults were able to correctly hear the same percentage of words when words were presented one at a time in noise. In Experiment 5, younger adults were tested under this S/N. Compared with older adults from Experiment 3, younger adults in this experiment recalled more words at all serial positions. The results are interpreted as showing that encoding in secondary memory is impaired by aging and noise either as a function of degraded sensory representations, or as a function of reduced processing resources. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The influence of list format and category headers on age differences in understanding medication instructions

We examined whether instructions are better understood and remembered when they contain organizational cues. Our previous research found that older and younger adults organize medication information in similar ways, suggesting that they have a schema for taking medication. In the present study, list formats (vs. paragraphs) emphasized the order of information and category headers emphasized the grouping of information specified by this schema. Experiment 1 examined whether list and header cues improve comprehension (answer time and accuracy) and recall for adults varying in age and working memory capacity (measured by a sentence span task). List instructions were better understood and recalled than paragraphs, and reduced age differences in answer time and span differences in accuracy. Headers reduced paragraph comprehension for participants with lower levels of working memory capacity, presumably because they were not salient cues in the paragraphs. Experiment 2 investigated if headers were more effective when more saliently placed in paragraphs and lists, and if list and header cues helped readers draw inferences from the instructions. List formats again reduced age differences in comprehension, especially reducing the time needed to draw inferences about the medication. While headers did not impair comprehension, these cues did impair recall. The present study suggests that list-organized instructions provide an environmental support that improves both older and younger adult comprehension and recall of medication information.     

Characteristics of associative learning in younger and older adults: Evidence from an episodic priming paradigm.

Two experiments investigated age differences in the encoding of associative information during a speeded naming task. In both experiments, semantically unrelated prime-target word pairs were presented 4 times, in either massed or spaced fashion, during the learning phase. An immediate or delayed test trial was presented following the fourth presentation. In Experiment 1, participants named both the primes and the targets. Younger and older adults showed similar benefits when naming targets that were part of a consistent prime-target pairing compared with targets presented with different primes at each presentation. In Experiment 2, participants named only the target word. Younger adults showed a benefit for consistently paired words, whereas older adults showed no benefit for consistently paired words. The results of the test trials showed a greater benefit for massed repeated words than for spaced repeated words at the immediate test and a reversed pattern at the delayed test. This spacing by test delay interaction was evident in response latency in Experiment 1 and in cued recall performance in Experiment 2. (PsycINFO Database Record (c) 2010 APA, all rights reserved)