Effects of item difficulty on the retrieval of solutions during cognitive skill acquisition: age differences

In cognitive skill learning, shifts to better strategies for obtaining solutions often occur while associations between problems and solutions are being strengthened. In two skill learning experiments, we examined the effects of item difficulty on the retrieval of solutions and the learning of problem-solution associations in younger and older adults. The results of both experiments demonstrated an 'easy effect' in both younger and older adults, such that the retrieval of solutions as well recognition memory for problems was best for the easier items. In addition, a 'hard effect' was found in younger adults, but not in older adults, whereby the retrieval of solutions as well as recognition memory for problems was better for harder items than for medium-difficulty items. The finding that increased computational demands at the item level delayed item memorization and the retrieval of solutions in older adults but not younger adults is consistent with a general-resources account of age-related differences in skill learning.     

Item learning in cognitive skill training: Effects of item difficulty

Item difficulty effects in skill learning were examined by giving participants extensive training with repeated alphabet arithmetic problems that varied in addend size (e.g., C ? D = ? is easy; C ? J = ? is harder). Recognition memory for the items, as measured by interpolated recognition tests, was acquired early in training and was unaffected by item difficulty. Memory for the solutions to items, as measured by the participants’ strategy reports that they had retrieved, rather than computed, the solution, was acquired later and was affected by item difficulty. Solutions to easier items were learned earlier in training for both young adults (18–24 years) and older adults (60–75 years), superimposed on an overall lower level of solution learning in older participants. The results suggest that the formation of associations between problems and their solutions is effortful and shares limited processing resources with the computational demands of the problem.     

Self-Regulated Learning in Younger and Older Adults: Does Aging Affect Metacognitive Control?

ABSTRACT

Two experiments examined whether younger and older adults' self-regulated study (item selection and study time) conformed to the region of proximal learning (RPL) model when studying normatively easy, medium, and difficult vocabulary pairs. Experiment 2 manipulated the value of recalling different pairs and provided learning goals for words recalled and points earned. Younger and older adults in both experiments selected items for study in an easy-to-difficult order, indicating the RPL model applies to older adults' self-regulated study. Individuals allocated more time to difficult items, but prioritized easier items when given less time or point values favoring difficult items. Older adults studied more items for longer but realized lower recall than did younger adults. Older adults' lower memory self-efficacy and perceived control correlated with their greater item restudy and avoidance of difficult items with high point values. Results are discussed in terms of RPL and agenda-based regulation models.     

Determinants of retrieval solutions during cognitive skill training: Source confusions

Diverse outcomes, both facilitative and disruptive, have been reported for the effect of interpolated item recognition tests on the acquisition of a cognitive skill. We collected data from a repeated set of 12 artificial arithmetic problems, soliciting compute/retrieve strategy reports after every trial. In one condition, a recognition test was administered after every three blocks of training. Recognition testing was found to depress retrieve frequencies in both younger and older adults, particularly for newly acquired items. Pairing training items with similar recognition foils mitigated these effects. This pattern of results could be explained by assuming that the participants based compute/retrieve decisions on item familiarity or frequency, tracked across both skill trials and recognition trials, and on a threshold influenced by source confusion. Variations in the threshold parameter could lead to depressed reports of item retrieval (our findings) or to elevated retrieval decisions, as has been shown in some other studies.     

The effects of presentation rate and retention interval on memory for items and associations in younger adults: A simulation of older adults’ associative memory deficit

Older adults show an associative deficit in episodic memory compared to younger adults. Previous research suggests both strategic and automatic binding deficits contribute to older adults’ poorer memory performance. Using behavioral manipulations designed to affect strategic and automatic binding of associations, three experiments attempted to simulate an associative deficit in younger adults. In these experiments participants learned face-scene pairs and then were given item and associative recognition memory tests. We manipulated the time allotted at encoding and retrieval to simulate strategic deficits, and the length of the retention interval to simulate automatic deficits. Results indicate that both manipulations separately contribute to a differential decline in associative memory, similar to the one shown by older adults, especially as reflected in the differential increase in false alarm rate in the associative memory test more than in the item memory test. Considerations of possible underlying brain mechanisms are discussed.     

A prelearning manipulation falsifies a pure associational deficit account of retrieval shift during skill acquisition

ABSTRACT

Older adults adopt memory-based response strategies during consistent practice more slowly and less completely than younger adults. In two experiments, participants either prelearned all, half, or none of the noun-pair stimuli prior to the completion of a standard noun-pair lookup task. Higher proportions of prelearning generally led to a faster and more complete strategic shift from visual scanning to memory retrieval during the lookup task, and a strong prelearning criterion for all items eliminated the age-related slowing of retrieval shift. However, the 50% prelearned condition resulted in strategy shift that was inconsistent with simple mechanistic associative learning, revealing a strategic set that was retrieval-avoidant in older adults.     

The effects of pure pair repetition on younger and older adults' associative memory

Although aging causes relatively minor impairment in recognition memory for components, older adults' ability to remember associations between components is typically significantly compromised, relative to that of younger adults. This pattern could be associated with older adults' relatively intact familiarity, which helps preserve component memory, coupled with a marked decline in recollection, which leads to a decline in associative memory. The purpose of the current study is to explore possible methods that allow older adults to rely on pair familiarity in order to improve their associative memory performance. Participants in 2 experiments were repeatedly presented with either single items or pairings of items prior to a study list so that the items and the pairs were already familiar during the study phase. Pure pair repetition (the effects of pair repetition after the effects of item repetition are taken into account) increased associative memory for older and younger adults. Findings based on remember and know judgments suggest that familiarity but not recollection is involved in mediating the repetition effect.     

Paying attention to binding: Further studies assessing the role of reduced attentional resources in the associative deficit of older adults

The present experiments investigated whether the observed associative deficit in older adults' episodic memory is mediated by a reduction of attentional resources. Using a dual-task procedure, younger and older participants studied lists of word pairs either under full attention or while performing a concurrent task. Both experiments showed that dividing attention did not cause a greater impairment to memory for associations than to memory for items in either age group. Furthermore, an analysis of concurrent task performance revealed that older adults' attentional costs for both learning and binding items were not larger than for learning items alone, relative to younger adults. These data provide support for a multicausal interpretation of older adults' memory deficits in which common, depleted attentional resources may be a mechanism that reduces memory for components of an episode in both older and younger adults under divided attention at encoding. In addition, older adults have a unique deficit in memory for the associations between the components, which does not seem to be resource dependent.     

Adult age differences in memory for name-face associations: The effects of intentional and incidental learning

Previous studies have indicated that older adults have a special deficit in the encoding and retrieval of associations. The current study assessed this deficit using ecologically valid name-face pairs. In two experiments, younger and older participants learned a series of name-face pairs under intentional and incidental learning instructions, respectively, and were then tested for their recognition of the faces, the names, and the associations between the names and faces. Under incidental encoding conditions older adults' performance was uniformly lower than younger adults in all three tests, indicating age-related impairments in episodic memory representations. An age-related deficit specific to associations was found under intentional but not under incidental learning conditions, highlighting the importance of strategic associative processes and their decline in older adults. Separate analyses of hits and false alarms indicate that older adults' associative deficit originated from high false alarm rates in the associative test. Older adults' high false alarm rates potentially reflect their reduced ability to recollect the study-phase name-face pairs in the presence of intact familiarity with individual names and faces.     

Directed forgetting in older adults using the item and list methods

Four experiments investigated age-group differences in directed forgetting. Experiments 1A and 1B used the item method with recall (1A) and recognition (1B). Both of these experiments showed evidence of directed forgetting for both younger and older adults. The list method was used in Experiments 2A (recall) and 2B (recognition). For these experiments, there was directed forgetting when recall, but not recognition, was the dependent measure. Again, these results were found for younger and older adults. These results are discussed in terms of how different presentation types lead to the use of different theoretical mechanisms of directed forgetting (e.g., differential encoding, retrieval inhibition). Thus, it appears that both older and younger adults engage in adaptive memory strategies.     

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.     

Cognitive skill learning: age-related differences in strategy shifts and speed of component operations

Younger and older adults solved novel arithmetic problems and reported the strategies used for obtaining solutions. Age deficits were demonstrated in the latencies for computing and retrieving solutions and in the shift from computation to retrieval. Rates of improvement within age groups were parallel for computations and retrievals, suggesting a single, age-attenuated mechanism that affects practice-related speedup. The age-related delay in strategy shift suggests either reluctance to use retrieval or an associative memory deficit. Experiment 1 showed that skill acquisition was unaffected by the presence and frequency of postresponse strategy probes for both age groups. Experiment 2 showed that pretraining item-learning operations facilitated subsequent item learning and that pretraining either item-learning operations or the algorithm did not alter the age trends.     

Age-related differences in the von restorff isolation effect

When one item is made distinct from the other items in a list, memory for the distinctive item is improved, a finding known as the isolation or von Restorff effect (after von Restorff, 1933). Although demonstrated numerous times with younger adults and children, this effect has not been found with older adults (Cimbalo & Brink, 1982). In contrast to the earlier study, we obtained a significant von Restorff effect for both younger and older adults using a physical manipulation of font colour. The effect size for older adults was smaller than that obtained for younger adults, confirming a prediction of Naveh-Benjamin's (2000) associative deficit hypothesis, which attributes age-related differences in memory performance to older adults' reduced ability to form associations. The findings are consistent with related research in which older adults demonstrate similar—but smaller—benefits for distinctive information to those for younger adults.     

The effects of emotion on younger and older adults’ monitoring of learning

Age-related differences in memory monitoring appear when people learn emotional words. Namely, younger adults’ judgments of learning (JOLs) are higher for positive than neutral words, whereas older adults’ JOLs do not discriminate between positive versus neutral words. In two experiments, we evaluated whether this age-related difference extends to learning positive versus neutral pictures. We also evaluated the contribution of two dimensions of emotion that may impact younger and older adults’ JOLs: valence and arousal. Younger and older adults studied pictures that were positive or neutral and either high or low in arousal. Participants made immediate JOLs and completed memory tests. In both experiments, the magnitude of older adults’ JOLs was influenced by emotion, and both younger and older adults demonstrated an emotional salience effect on JOLs. As important, the magnitude of participants’ JOLs was influenced by valence, and not arousal. Emotional salience effects were also evident on participants’ free recall, and older adults recalled as many pictures as did younger adults. Taken together, these data suggest that older adults do not have a monitoring deficit when learning positive (vs. neutral) pictures and that emotional salience effects on younger and older adults’ JOLs are produced more by valence than by arousal.     

Age-Related Changes in the use of Study Context to Increase Recollection

ABSTRACT

We examined how context presented at study affects recollection of words in younger and older adults. In Experiment 1, participants studied words presented with a picture of a face (context-rich condition) or a rectangle (context-weak condition), and subsequently made ‘Remember’, ‘Know’, or ‘New’ judgments to words presented alone. Younger, but not older, adults showed higher Remember accuracy following rich- than weak-context trials. In Experiment 2, we manipulated the type of processing engaged during the encoding of context–word pairs. Younger and older adults studied words presented with a picture of a face under a surface feature (gender) or binding feature (match) instruction condition. Both age groups showed higher Remember accuracy in the binding than surface instruction condition. Results suggest that providing rich contextual detail at encoding boosts later item recollection in younger adults. Older adults, however, do not spontaneously engage in the processes required to boost recollection, though instructional manipulation during encoding lessens this deficit.     

Age-related differences in the von Restorff isolation effect

When one item is made distinct from the other items in a list, memory for the distinctive item is improved, a finding known as the isolation or von Restorff effect (after von Restorff, 1933). Although demonstrated numerous times with younger adults and children, this effect has not been found with older adults (Cimbalo & Brink, 1982). In contrast to the earlier study, we obtained a significant von Restorff effect for both younger and older adults using a physical manipulation of font colour. The effect size for older adults was smaller than that obtained for younger adults, confirming a prediction of Naveh-Benjamin's (2000) associative deficit hypothesis, which attributes age-related differences in memory performance to older adults' reduced ability to form associations. The findings are consistent with related research in which older adults demonstrate similar—but smaller—benefits for distinctive information to those for younger adults.     

Effects of aging on the magnitude and accuracy of quality-of-encoding judgments

Age invariance in monitoring associative learning has been the norm in numerous investigations concerning how accurately people predict future recall, predictions that are based partly on people's beliefs about forgetting. In this study, we obtained a measure of monitoring that is minimally influenced by beliefs about forgetting. Participants made quality-of-encoding (QUE) judgments by rating how well each item had been encoded. In 2 experiments, older and younger adults studied 60 paired-associate items; immediately after studying each one, they made a QUE judgment. Each item was presented at a 4-s or 8-s presentation rate. QUEs from both age groups were sensitive to the production of different strategies, presentation rate, and item characteristics. Reliable age differences in the correlation of QUEs and subsequent recall were found for related items but not for unrelated items. The outcomes indicate similar processes for generating QUE judgments by older and younger adults, but they also suggest the possibility of an age-related deficit in the accuracy of monitoring encoding in some experimental conditions.     

Facilitation and impairment of event memory produced by photograph review

Selectively reviewing some items from a larger set of previously learned items increases memory for the items that are reviewed but may also be accompanied by a cost: Memory for the nonreviewed items may be impaired relative to cases where no review occurs at all. This cost to nonreviewed items has primarily been shown in contexts of verbal list learning and in situations where the reviewed and nonreviewed items are categorically or semantically related. Using a more naturalistic impetus to selective review--photographs relating to previously experienced events--we assessed whether the memory of older and younger adults for unrelated complex activities that they themselves had performed was also impaired due to nonreview. Both younger and older adults showed impaired memory for nonreviewed activities when tested with free recall (Experiment 1), but not when tested with recognition or cued recall (Experiment 2). If mitigating retrieval cues are unavailable, selective review may impair memory for nonreviewed everyday events.     

Attention and the acquisition of new knowledge: their effects on older adults' associative memory deficit

Older adults experience a selective associative memory deficit by demonstrating intact item memory relative to impaired associative memory when compared with younger adults. Age-related deficits in associative memory have been suggested to arise from declines in attentional resources, and the role of attention during encoding and retrieval in associative memory for words and their spatial locations was investigated in the current experiment. Additionally, the tendency of younger and older adults to use knowledge acquired during encoding to improve their associative memory judgments through a strategic associative memory process was also investigated. Younger and older adults studied a list of words with each word belonging to one of four categories, which followed one of four mathematical probability structures for their presentation. Older adults exhibited intact item memory and impaired associative memory relative to full attention younger adults. In addition, both older and younger adults demonstrated an ability to engage in strategic associative memory, by learning and later using the probability structure introduced at study to guide their associative memory judgments. In contrast, dividing the attention of younger adults during encoding impaired item memory, associative memory and strategic associative memory, whereas dividing attention at retrieval did not result in similar deficits. These data add to a growing body of literature demonstrating older adults to exhibit a selective associative memory deficit that is not simulated by dividing the attention of younger adults at encoding or retrieval. Furthermore, younger and older adults maintain the ability to use new knowledge to guide their associative judgments.