Orienting tasks as moderators of narrative and expository text recall in adulthood.

Incidental narrative and expository prose memory of 60 older adults (mean age 71.6 yrs) and 60 younger adults (mean age 23.6 yrs) was assessed following orienting tasks that emphasized either relational (sentence scrambling) or individual proposition (letter deletion) information or following a control condition. Orienting tasks were done capably, but older adults took longer and made more errors on the letter-deletion task than did younger adults. Age differences in recall were observed consistently for expository texts, but for narrative texts, age differences in recall were observed only when letters were deleted. If orienting tasks overtax older adults' processing resources or emphasize shallow information, recall gains may be minimal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sequential and coordinative complexity in time–accuracy functions for mental arithmetic.

Time–accuracy functions for tasks involving single-digit mental addition and subtraction were derived in a sample of 18 younger (mean age?=?21.7 years) and 16 older adults (mean age?=?68.8 years). Sequential complexity was manipulated by varying the number of operations (5 vs. 10); coordinative complexity was induced by bracketing. Age differences were apparent in the coordinative conditions, even though no age difference was present in the sequential conditions. This indicates that the age difference under conditions of high coordinative demands could not be attributed solely to a decline in basic speed of processing. The Age?×?Complexity interaction was due to larger onset times and lower asymptotic performance by the older adults in the coordinative conditions but not due to to rate of approach to the asymptote. This implies that coordinative demands do not differentially hurt access from semantic memory in older adults; however, coordinative demands do have disproportionately negative consequences for computation speed and self-monitoring in older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age effects on social cognition: Faces tell a different story.

The authors administered social cognition tasks to younger and older adults to investigate age-related differences in social and emotional processing. Although slower, older adults were as accurate as younger adults in identifying the emotional valence (i.e., positive, negative, or neutral) of facial expressions. However, the age difference in reaction time was largest for negative faces. Older adults were significantly less accurate at identifying specific facial expressions of fear and sadness. No age differences specific to social function were found on tasks of self-reference, identifying emotional words, or theory of mind. Performance on the social tasks in older adults was independent of performance on general cognitive tasks (e.g., working memory) but was related to personality traits and emotional awareness. Older adults also showed more intercorrelations among the social tasks than did the younger adults. These findings suggest that age differences in social cognition are limited to the processing of facial emotion. Nevertheless, with age there appears to be increasing reliance on a common resource to perform social tasks, but one that is not shared with other cognitive domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Success and failure at dual-task coordination by younger and older adults.

Dual-task processing was explored in younger and older adults in 2 experiments that used a tone discrimination and a letter discrimination task. To encourage parallel processing if that was possible, the authors presented the stimuli for the 2 tasks simultaneously, and participants were instructed to withhold their responses until both were ready. The authors found no evidence for parallel processing and no evidence that the management of central processing of dual tasks is qualitatively different in older adults than it is in younger adults. When one response was verbal and the other manual, the 2 responses closely coincided. When both responses were manual, the authors did find that the first response was not delayed enough to coincide with the 2nd and that this underestimation was greater in older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A demonstration of dual-task performance without interference in some older adults.

Highly efficient dual-task processing is demonstrated when reaction time to each of two tasks does not differ between the dual-task situation and the single-task situation. This has been demonstrated reliably in younger adults; nevertheless, the two extant studies of extensive dual-task training did not find evidence for it in any elderly adult. The origins of age-related differences after training were explored in a study in which the stimuli for the two tasks were perfectly redundant although two distinct responses were required. The dual-task situation thus greatly reduced the demands of stimulus categorization while still requiring two response selections and two response executions. After only limited training 8 of 8 younger adults and 5 of 8 older adults showed performance consistent with highly efficient processing. Three older adults failed to show this even after 12 training sessions. The results implicate stimulus categorization more than response selection as an important locus of inefficient dual-task processing, particularly for older adults. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Age differences in dual-task interference are localized to response-generation processes.

Dual-task differences in younger and older adults were explored by presenting 2 simple tasks, with the onset of the 2nd task relative to the 1st task carefully controlled. The possibility of an age-related reduction in the ability to generate and execute 2 similar motor programs was explored by requiring either a manual response to both tasks or a manual response to the 1st and an oral response to the 2nd and was confirmed by the evidence. The age-related interference was greater than would be expected from a general slowing of processing in older adults. The possibility of an age-related reduction in the capacity to process 2 tasks in the same perceptual input modality was explored by presenting both tasks in the visual modality or the 1st task in the auditory modality and the 2nd task in the visual modality and was not supported by the evidence. There was greater interference when both tasks were in the same modality, but it was equivalent for older and younger adults. Age differences in dual-task interference appear quite localized to response-generation processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Immunohistochemical localisation of alpha1B-adrenergic receptors in the rat iris

This article reports results from a meta-analysis on adult age differences in the negative priming effect (21 studies on identity negative priming and 8 on location negative priming). Both younger and older adults were found to be susceptible to the negative priming effect in identity and location tasks. Effect sizes were homogeneous for both tasks, indicating that the data are adequately described without reference to moderator variables. State trace analysis on identity tasks, in which mean latencies in negative priming conditions were regressed onto mean latencies in baseline conditions, showed (a) that in both age groups the negative priming effect is proportional rather than additive and (b) that the negative priming effect is smaller in older adults as compared with younger adults.     

Speed of information processing as a mediator between age and free-recall performance.

A combined experimental and individual differences approach was used to investigate the mediating role of task-specific and task-independent speed of information processing measures in the relationship between age and free-recall performance. 36 younger adults (mean age 21 yrs) and 36 older adults (mean age 73 yrs) participated. Participants were required to encode 3 lists of words for immediate recall, by rehearsing the words aloud, once, twice, and 3 times. Participants' speed of information processing was assessed by 3 measures: rehearsal time, articulation speed, and scores on the Digit Symbol Substitution Test (DSST). Working memory was also assessed by a backward word-span measure. As predicted, younger adults recalled more words after rehearsing words 3 times rather than once, whereas older adults' recall did not increase with increasing numbers of rehearsals. Younger adults were faster on all speed-of-processing measures and had higher backward word span than did older adults. Task-independent speed of processing, measured by DSST scores and articulation speed, mediated the relationship between age and free recall. Scores on the DSST appear to reflect a fundamental difference between younger and older adults that influences recall performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and the negative priming effect: A meta-analysis.

This article reports results from a meta-analysis on adult age differences in the negative priming effect (21 studies on identity negative priming and 8 on location negative priming). Both younger and older adults were found to be susceptible to the negative priming effect in identity and location tasks. Effect sizes were homogeneous for both tasks, indicating that the data are adequately described without reference to moderator variables. State trace analysis on identity tasks, in which mean latencies in negative priming conditions were regressed onto mean latencies in baseline conditions, showed (a) that in both age groups the negative priming effect is proportional rather than additive and (b) that the negative priming effect is smaller in older adults as compared with younger adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential Age Effects on Attention-Based Inhibition: Inhibitory Tagging and Inhibition of Return.

The purpose of this study was to determine whether 2 forms of attentional inhibition, inhibition of return (IOR) and inhibitory tagging, are differentially affected by the aging process. The authors tested 24 younger adults (mean age = 22 years) and 24 older adults (mean age = 69 years) on a combined IOR and Stroop task (Vivas & Fuentes, 2001). As predicted, younger adults' performance was consistent with inhibitory tagging of objects at inhibited locations. Although older adults demonstrated intact IOR, there was no evidence of inhibitory tagging. The results suggest that age deficits in inhibition are selective. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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)     

The moderating influence of physical fitness on age gradients in vigilance and serial choice responding tasks.

The moderating influence of physical fitness on age gradients in measures obtained from vigilance and serial choice responding tasks is examined in a sample of 90 postal workers. Physiological data relating to aerobic fitness determined fitness level within 2 age groups: younger participants ages 18 to 30 years (M ?=?25.19; 24 men, 24 women) and older participants ages 43 to 62 years (M ?=?49.19; 20 men, 22 women). A performance decrement across time was found in several measures, and some variation as a function of age was apparent. However, post hoc statistical analyses did not indicate this was due to older adults underperforming younger adults. According to predictions, significant Age?×?Fitness interactions showed older less fit workers to consistently underperform other participants. The findings suggest that older less fit individuals have lower signal sensitivity and processing speed than older fitter people and younger individuals. Results are discussed in relation to underlying physiological mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The psychological refractory period: Evidence for age differences in attentional time-sharing.

Reports 2 psychological refractory period (PRP) experiments in which the stimulus onset asynchrony (SOA) between Task 1 and 2 was 150, 250, 600, and 1,100 msec for both younger and older adults. H. Pashler's (1994) response-selection bottleneck theory predicts that SOA manipulations should not affect Task 1 performance, but that reaction time (RT) for Task 2 should increase as the SOA between the 2 tasks decreases (i.e., the classical PRP effect). In Exp 1, older adults showed a larger PRP effect, although Task 1 RT was affected by SOA, suggesting that Ss were grouping their responses on some trials. That is, Ss were holding their response for Task 1 until they had completed processing Task 2, and then they responded to both tasks almost simultaneously. However, a subset of Ss who showed no evidence of response grouping on Task 1 continued to show a larger PRP effect for older adults on Task 2. In Exp 2, older adults continued to show a larger PRP effect for Task 2, and Task 1 performance was unaffected by SOA. Findings provide evidence that older adults exhibit a decrement in time-sharing at the response-selection stage of processing. Results suggest that attentional time-sharing needs to be added to the list of topics examined in aging research on varieties of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of representations in age differences in analogical reasoning.

Age-related declines in the efficiency of a number of cognitive tasks have been postulated to be attributable to decreases with age in the quality of internal representations used to mediate performance on those tasks. This proposal was investigated in a geometric analogies task by manipulating variables (i.e., the number of elements per term and the temporal delay between presentation of pairs of terms) assumed to affect the quality or stability of internal representations. As expected, the performance of older adults was impaired more than that of young adults by these manipulations. Further analyses revealed that these representational deficits may be due to a reduction of approximately 40% in the quantity of some type of processing resource between, approximately, 20 and 70 years of age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of perceptual and conceptual processing on memory for words and voice: different patterns for young and old

In two experiments younger and older adults listened to a list of words presented auditorily by two speakers. The subjects processed each word either perceptually (voice judgements) or conceptually (pleasantness judgements), and were then given memory tasks for the words and the presenting voice. In the word-recognition task the two age groups benefited equally from conceptual as opposed to perceptual processing. In the voice memory task, however, conceptual processing improved performance relative to perceptual processing in the younger subjects (significantly so in Experiment 1), but conceptual processing was associated with decreased performance in the older group (significantly so in Experiment 2). These results suggest that whereas older subjects exhibit a trade-off in memory for item and attribute information, younger subjects exhibit a pattern of support, in which conceptual processing benefits memory for both items and their attributes.     

Effects of familiarity of task and choice on the functional performance of younger and older adults.

An experiment was conducted to compare the functional performance of younger and older adults on familiar and unfamiliar tasks under 2 conditions of perceived control. Specifically, the relation between age and motor and process skills was examined. The familiar tasks were simple cooking tasks, whereas the unfamiliar tasks were contrived, meaningless tasks developed for this study. Younger and older adults did not differ in the ratings of the familiarity of the tasks, but results from 2 Age?×?Task?×?Choice analyses of variance demonstrated a significant age difference for motor and process skills under all conditions. This suggests that older adults demonstrate age-related decline, even with activities that take motivational, experiential, and ecological validity components into account. For the process skills scale, there was also a significant main effect for choice. These results support the concept that perceived control may improve performance, but not differentially for older adults; that is, younger and older adults both demonstrated improved process performance when given their choice of tasks. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

A comparison of the factor structure of processing speed for younger and older adults: Testing the assumption of measurement equivalence across age groups.

The purpose of this study was to investigate measurement equivalence of processing speed measures for different age groups. A structural equation modeling approach was used to investigate a measurement model and the factorial invariance between younger and older adults on speed measures. The analyses concurrently examined whether speed-related abilities dedifferentiate with increasing age. One hundred and forty-four younger and 105 older adults completed 9 measures designed to assess motor speed, alphanumeric speed, and geometric speed. Results indicated that although the number of factors and the factor loadings were invariant across age groups, the interfactor correlations, the variance-covariance matrices, and the unique variances differed across groups. Furthermore, a second-order speed factor seemed to explain much of the variance in the 3 first-order factors, although this higher order factor accounted for slightly more variance among the older group than among the younger group. The results suggest that there is sufficient evidence of measurement equivalence on the current speed measures across the 2 adult age groups and, in addition, provide evidence of dedifferentiation. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Cultural variation in verbal versus spatial neuropsychological function across the life span.

Established culture-invariant measures are needed for cross-cultural assessment of verbal and visuospatial speed of processing and working memory across the life span. In this study, 32 younger and 32 older adults from China and from the United States were administered numerically based and spatially based measures of speed of processing and working memory. Chinese superiority on the numerically based tasks was found for younger adults. Age and increasing task demands diminished this cultural effect, as predicted by the framework proposed by D. C. Park, R. Nisbett, and T. Hedden (1999). However, the visuospatial measures of both working memory and speed of processing did not differ cross-culturally for either age group. The authors concluded that these visuospatial measures provide culture-invariant estimates of cognitive processes in East Asian and Western cultures, but that numerically based tasks show evidence of cultural and linguistic biases in performance levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adult Age and Digit Symbol Substitution Performance: A Meta-Analysis.

This article reports the results of a meta-analysis of the effects of age, education, and estimated year of measurement on scores from the Wechsler Adult Intelligence Scale and the Wechsler Adult Intelligence Scale-Revised Digit Symbol Substitution Test. Analysis of effect sizes for age reported in 141 studies published between 1986 and 2002 indicated a mean standardized difference of -2.07. Age accounted for 86% of the variance in a regression model using age, education, and year submitted as predictors of Digit Symbol scores. There was no association between years of education or year submitted and Digit Symbol scores for younger adults or older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)