Effects of age and a divided attention task presented during encoding and retrieval on memory.

The present studies were designed to examine age differences in memory when attention was divided during encoding, retrieval, or at both times. In Experiment 1, Ss studied categorized words while performing a number-monitoring task during encoding, retrieval, or at both times. Older Ss' free recall and clustering performance declined more than that of young Ss when attention was divided at encoding, but there was no similar age interaction when divided attention occurred at retrieval. In Experiment 2, the task demands at retrieval were increased by using a fast-paced, cued-recall task. The results remained unchanged from Experiment 1. Again, an age interaction occurred with divided attention at encoding but not at retrieval. These results were unexpected, given the emphasis in the memory-aging literature on increased difficulty of retrieval by older adults. The findings pose difficulties for limited processing resource views of age differences in memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in reading with distraction: Sensory or inhibitory deficits?

Two experiments examined how sensory acuity affects age differences in susceptibility to interference in the reading-with-distraction task. In both experiments, older and younger adults read texts in an italic font and were required to ignore distractor words in an upright font. Experiment 1 examined whether the age-related increase in distractibility can be simulated in younger adults by reducing their visual acuity. Experiment 2 investigated whether the age differences in distractibility disappear if visual acuity is equated across all participants in both age groups. Both experiments showed that an impairment in visual acuity leads to increased interference in the reading-with-distraction task. However, older adults were much more impaired by the distractor material than younger adults with reduced visual acuity (Experiment 1). The age differences in the reading-with-distraction task persisted when visual acuity was equated between older and younger adults (Experiment 2). We conclude that the age-related increase in susceptibility to interference in the reading-with-distraction task is not solely due to perceptual deficits of older adults but arises from a deficit in higher cognitive processes such as inhibitory attention. Nevertheless, sensory acuity has to be taken into account as a potential confounding factor in perceptually demanding visual attention tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A rational approach to managing stage I nonseminomatous germ cell cancer

Four studies examined the effects of divided attention in younger and older adults. Attention was divided at encoding or retrieval in free recall (Experiment 1), cued recall (Experiments 2 and 3), and recognition (Experiment 4). Dividing attention at encoding disrupted memory performance equally for the two age groups; by contrast, for both age groups, dividing attention at retrieval had little or no effect on memory performance. Secondary task reaction times (RTs) were slowed to a greater extent for the older adults than for the younger adults, especially at retrieval. Age-related differences in RT costs at retrieval were largest in free recall, smaller in cued recall, and smallest in recognition. These results provide evidence for an age-related increase in the attentional demands of encoding and retrieval.     

The attentional demands of encoding and retrieval in younger and older adults: I. Evidence from divided attention costs.

Four studies examined the effects of divided attention in younger and older adults. Attention was divided at encoding or retrieval in free recall (Experiment 1), cued recall (Experiments 2 and 3), and recognition (Experiment 4). Dividing attention at encoding disrupted memory performance equally for the two age groups; by contrast, for both age groups, dividing attention at retrieval had little or no effect on memory performance. Secondary task reaction times (RTs) were slowed to a greater extent for the older adults than for the younger adults, especially at retrieval. Age-related differences in RTs costs at retrieval were largest in free recall, smaller in cued recall, and smallest in recognition. These results provide evidence for an age-related increase in the attentional demands of encoding and retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related differences in switching between cognitive tasks: Does internal control ability decline with age?

The present study tested the hypothesis that older adults establish a weaker task set than younger adults and therefore rely more on stimulus-triggered activation of task sets. This hypothesis predicts that older adults should have difficulty with task switches, especially when the stimuli-responses are associated with multiple, competing tasks. Weak task preparation, however, could actually benefit older adults when performing an unexpected task. The authors tested this prediction in Experiment 1 using a repeating AABB task sequence, with univalent and bivalent stimuli intermixed. On some univalent trials, participants received an unexpected task. Contrary to the authors' predictions, expectancy costs were not smaller for older adults. Similar findings were obtained in Experiments 2 and 3, in which the authors used a task-cueing paradigm to more strongly promote deliberate task preparation. The authors found no disproportionate age effects on switch costs but did find age effects on bivalence costs and mixing costs. The authors conclude that older adults do experience extra difficulty dealing with stimuli associated with 2 active tasks but found no evidence that the problem specifically stems from an increased reliance on bottom-up task activation rather than top-down task preparation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of attention on age-related relational memory deficits: Evidence from a novel attentional manipulation.

Healthy aging is often accompanied by episodic memory decline. Prior studies have consistently demonstrated that older adults show disproportionate deficits in relational memory (RM) relative to item memory (IM). Despite rich evidence of an age-related RM deficit, the source of this deficit remains unspecified. One of the most widely investigated factors of age-related RM impairment is a reduction in attentional resources. However, no prior studies have demonstrated that reduced attentional resources are the critical source of age-related RM deficits. Here, we used qualitatively different attention tasks and tested whether reduced attention for relational processing underlies the RM deficit observed in aging. In Experiment 1, we imposed either item-detection or relation-detection attention tasks on young adults during episodic memory encoding and found that only the concurrent attention task that involves relational processing disproportionately impaired RM performance in young adults. Moreover, by ruling out the possible confound of task difficulty on the disproportionate RM impairment, we further demonstrated that reduced relational attention is a key factor for the age-related RM deficit. In Experiment 2, we replicated the results from Experiment 1 by using different materials of stimuli and found that the effect of relational attention on RM is material general. The results of Experiment 2 also showed that reducing attentional resources for relational processing in young adults strikingly equated their RM performance to that of older adults. Thus, this study documents the first evidence that reduced attentional resources for relational processing are a critical factor for the relational memory impairment observed in aging. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Event-based prospective memory and executive control of working memory

In 5 experiments, the character of concurrent cognitive processing was manipulated during an event-based prospective memory task. High- and low-load conditions that differed only in the difficulty of the concurrent task were tested in each experiment. In Experiments 1 and 2, attention-demanding tasks from the literature on executive control produced decrements in prospective memory. In Experiment 3, attention was divided by different loads of articulatory suppression that did not ultimately lead to decrements in prospective memory. A high-load manipulation of a visuospatial task requiring performance monitoring resulted in worse prospective memory in Experiment 4, whereas in Experiment 5 a visuospatial task with little monitoring did not. Results are discussed in terms of executive functions, such as planning and monitoring, that appear to be critical to successful event-based prospective memory.     

Differential age-related processing limitations in recall and recognition tasks.

The degree to which processing resources are responsible for age differences in performance on recall and recognition tasks was examined in this study. To examine this, a secondary task incorporating a memory component (digit preloads) was implemented during retrieval. Results revealed that older adults, relative to younger adults, exhibited greater decrements in secondary task performance as the difficulty of the secondary task increased. These age differences were greater in the recall task than in the recognition task. Hierarchical regression analyses indicated that speed accounted for the largest proportion of age-related variance in the recall task while both speed and working memory contributed to much of the secondary task variance. Results confirm the hypothesis that recall requires greater processing capacity than recognition and that older adults have greater processing-capacity limitations than younger adults. (PsycINFO Database Record (c) 2011 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)     

Age differences in mental multiplication: evidence for peripheral but not central decrements

This study reports two mental multiplication experiments that were designed to measure age differences in central and peripheral processes. Experiment 1 varied task type (verification vs production), and Experiment 2 varied exposure duration (presentation until response, 600 ms, and 300 ms) on a production task. Neither experiment showed evidence of age differences in central processes (e.g., retrieval speed); however, there was some evidence of a peripheral-process (e.g., encoding) decrement for older adults. Specifically, there were no Age X Problem Size interactions for either experiment. Experiment 2 revealed decreasing age differences as problem difficulty increased. Indeed, for the 300-ms exposure duration, there were no age differences in RT or error rate. These results suggest that the magnitude of age differences in central processing speed are significantly less extreme than are age differences for peripheral processing speed for this type of mental arithmetic task. Also, older adults, in general, may have a higher skill level for basic fact retrieval in mental arithmetic than do young adults.     

One-trial associative priming of nonwords in young and older adults.

In this article, three experiments in which single-trial associative priming for nonwords was investigated in young and older adults in a pronunciation task are reported. During an encoding task, associative priming was observed for young and older adults, although cued recall was near zero for both groups. Associative priming for young and older adults was found under full attention conditions, but when attention was divided at study, associative priming was observed in Experiment 3, but not in Experiment 2. Divided attention also disrupted recognition memory for new associations in young and older adults. The results limit the generality of findings of age-related decrements in associative priming by showing an absence of such decrements in tasks that do not require elaborative processing during encoding. They also argue against G. Musen and L. Squire's (see record 1993-34212-001) suggestion that formation of new connections in implicit memory requires multiple study opportunities, whereas declarative memory is specialized for rapid acquisition of new associations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does differential strategy use account for age-related deficits in working-memory performance?

The strategy-deficit hypothesis states that age differences in the use of effective strategies contribute to age-related deficits in working memory span performance. To evaluate this hypothesis, strategy use was measured with set-by-set strategy reports during the Reading Span task (Experiments 1 and 2) and the Operation Span task (Experiment 2). Individual differences in the reported use of effective strategies accounted for substantial variance in span performance. In contrast to the strategy-deficit hypothesis, however, young and older adults reported using the same proportion of normatively effective strategies on both span tasks. Measures of processing speed accounted for a substantial proportion of the age-related variance in span performance. Thus, although use of normatively effective strategies accounts for individual differences in span performance, age differences in effective strategy use cannot explain the age-related variance in that performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging, source, and decision criteria: When false fame errors do and do not occur.

Two experiments investigated the influence of decision criteria on source memory performance of older adults and younger adults. Experiment 1 used the false fame paradigm, which encourages people to use relatively loose decision criteria when making what are, in essence, source judgments. Consistent with previous research, older adults made more false fame errors than younger adults. Experiment 2 was identical to Experiment 1 except that the fame judgments were made with the traditional source task format that encourages relatively stringent decision criteria when making source judgments: Possible sources were listed, and participants categorized names in terms of their source. In contrast to Experiment 1, older adults reduced their false fame errors to the level of younger adults. Encouraging older adults to use relatively stringent decision criteria when making source discriminations can reduce age differences in source misattributions. (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)     

Age differences in recall and recognition.

An experiment is reported in which young and elderly adults performed cued-recall and recognition tests while carrying out a choice reaction-time task. An analysis of covariance, with recognition performance as the covariate, showed a reliable age decrement in recall. It was therefore concluded that older people perform more poorly on recall tasks than they do on recognition tasks. Performance on the secondary (reaction time) task showed that recall was associated with greater resource "costs" than was recognition and that this effect was amplified by increasing age. The results are in line with the suggestion that recall requires more processing resources than does recognition and that such resources are depleted as people grow older. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging, exercise, and attention.

Investigated the relationship among aging, attentional processes, and exercise in 2 experiments. First, age differences were examined on 2 attentional tasks: a time-sharing task and an attentional flexibility task. Young adults alternated attention between 2 sequenced tasks more rapidly and time-shared the processing of 2 tasks more efficiently than older adults. Then the effect of aerobic exercise was investigated on the same 2 attentional tasks in older adults. Following the 10-wk exercise program, older exercisers showed substantially more improvement in alternation speed and time-sharing efficiency than older controls. Interestingly, this exercise effect was specific to dual-task processing. Both groups of Ss showed equivalent effects on single-task performance. These results indicate that aerobic exercise can exert a beneficial influence on the efficiency of at least 2 different attentional processes in older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The nature of gestures' beneficial role in spatial problem solving.

Co-thought gestures are hand movements produced in silent, noncommunicative, problem-solving situations. In the study, we investigated whether and how such gestures enhance performance in spatial visualization tasks such as a mental rotation task and a paper folding task. We found that participants gestured more often when they had difficulties solving mental rotation problems (Experiment 1). The gesture-encouraged group solved more mental rotation problems correctly than did the gesture-allowed and gesture-prohibited groups (Experiment 2). Gestures produced by the gesture-encouraged group enhanced performance in the very trials in which they were produced (Experiments 2 & 3). Furthermore, gesture frequency decreased as the participants in the gesture-encouraged group solved more problems (Experiments 2 & 3). In addition, the advantage of the gesture-encouraged group persisted into subsequent spatial visualization problems in which gesturing was prohibited: another mental rotation block (Experiment 2) and a newly introduced paper folding task (Experiment 3). The results indicate that when people have difficulty in solving spatial visualization problems, they spontaneously produce gestures to help them, and gestures can indeed improve performance. As they solve more problems, the spatial computation supported by gestures becomes internalized, and the gesture frequency decreases. The benefit of gestures persists even in subsequent spatial visualization problems in which gesture is prohibited. Moreover, the beneficial effect of gesturing can be generalized to a different spatial visualization task when two tasks require similar spatial transformation processes. We concluded that gestures enhance performance on spatial visualization tasks by improving the internal computation of spatial transformations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The age prospective memory paradox: Young adults may not give their best outside of the lab.

Previous research has identified the age prospective memory paradox of age-related declines in laboratory settings in contrast to age benefits in naturalistic settings. Various factors are assumed to account for this paradox, yet empirical evidence on this issue is scarce. In 2 experiments, the present study examined the effect of task setting in a laboratory task and the effect of motivation in a naturalistic task on prospective memory performance in young and older adults. For the laboratory task (Experiment 1, n = 40), we used a board game to simulate a week of daily activities and varied features of the prospective memory task (e.g., task regularity). For the naturalistic task (Experiment 2, n = 80), we instructed participants to try to remember to contact the experimenter repeatedly over the course of 1 week. Results from the laboratory prospective memory tasks indicated significant age-related decline for irregular tasks (p = .006) but not for regular and focal tasks. In addition, in the naturalistic task, the age benefit was eliminated when young adults were motivated by incentives (F     

The influence of apoe status on episodic and semantic memory: Data from a population-based study.

In a prospective cohort study, the authors demonstrated a more pronounced ε4-related deficit for participants 70 years of age and older in tasks assessing episodic recall. Apolipoprotein E (APOE) and age interacted for episodic memory tasks, whereas the interaction for semantic memory tasks was between APOE and test wave. Heterozygotes of ε4 between middle-age and young-old participants performed at a higher level than noncarriers of this allele in recall tasks. A dose effect was found such that carriers of 2 ε4 alleles failed more profoundly in acquiring and recollecting episodic information than carriers of 1 ε4 allele, who in turn failed more than carriers of non-ε4 alleles. The pattern of findings observed for older ε4 carriers suggests that these individuals have particular difficulty when the executive task demands are high. Several factors (e.g., smaller hippocampal volumes, less effective neural repair mechanisms) may account for these findings. On the basis of the data obtained, the authors argue that analyses of the effect of specific genes in cognition should be accompanied by assessment of performance at a specific level, with due attention to the individual's age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual word recognition without central attention: Evidence for greater automaticity with advancing age.

The present experiments examined the automaticity of word recognition. The authors examined whether people can recognize words while central attention is devoted to another task and how this ability changes across the life span. In Experiment 1, a lexical decision Task 2 was combined with either an auditory or a visual Task 1. Regardless of the Task 1 modality, Task 2 word recognition proceeded in parallel with Task 1 central operations for older adults but not for younger adults. This is a rare example of improved cognitive processing with advancing age. When Task 2 was nonlexical (Experiment 2), however, there was no evidence for greater parallel processing for older adults. Thus, the processing advantage appears to be restricted to lexical processes. The authors conclude that greater cumulative experience with lexical processing leads to greater automaticity, allowing older adults to more efficiently perform this stage in parallel with another task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)