Loneliness is a unique predictor of age-related differences in systolic blood pressure

A population-based sample of Caucasians, African Americans, and Latino Americans, 50-68 years of age (M = 57.5), from Cook County, Illinois (N = 229), was tested to examine how loneliness and co-occurring psychosocial factors (depressive symptoms, perceived stress, social support, and hostility) were related to indices of cardiovascular and endocrine functioning. Extending prior research, the authors found that loneliness was associated with elevated systolic blood pressure (SBP) and age-related increases in SBP, net of demographic variables, health behavior variables, and the remaining psychosocial factors. Loneliness was not associated with differences in autonomic or endocrine functioning. Although the results are limited by the cross-sectional methods used, they are consistent with the hypothesis that cardiovascular disease contributes to increased morbidity and mortality among lonely individuals.     

Adult age differences in task switching

Age differences in 2 components of task-set switching speed were investigated in 118 adults aged 20 to 80 years using task-set homogeneous (e.g., AAAA ...) and task-set heterogeneous (e.g., AABBAABB ... ) blocks. General switch costs were defined as latency differences between heterogeneous and homogeneous blocks. whereas specific switch costs were defined as differences between switch and nonswitch trials within heterogeneous blocks. Both types of costs generalized over verbal, figural, and numeric stimulus materials; were more highly correlated to fluid than to crystallized abilities; and were not eliminated after 6 sessions of practice, indicating that they reflect basic and domain-general aspects of cognitive control. Most important, age-associated increments in costs were significantly greater for general than for specific switch costs, suggesting that the ability to efficiently maintain and coordinate 2 alternating task sets in working memory instead of 1 is more negatively affected by advancing age than the ability to execute the task switch itself.     

Using a modified lag task to measure adult age differences in working memory

Four groups of adults, ages 40 to 70+ years, took the Modified Lag Task which requires that participants remember lists of words and subsequently recall the first, second, or third word from the end of the list. Previously, the task showed convergent validity with the operation span (a complex span measure) and a divergent validity with the digit span (a simple span measure). To establish predictive validity, the present study was designed to assess if this task could separate four age groups in working memory performance. The present study found support for the validity of the Modified Lag Task; however, additional research is warranted to further develop the construct validity of this task.     

Age-related differences in ambulatory blood pressure during daily stress: evidence for greater blood pressure reactivity with age

Prior research on age and emotions has found that older adults may show better physiological regulation to stressful stimuli than do younger adults. However, the stress reactivity literature has shown that age is associated with higher cardiovascular reactivity to laboratory stress (J. R. Jennings et al., 1997). The authors investigated these conflicting findings further by examining daily ambulatory blood pressure in 428 middle-aged to older adults. Consistent with the age and reactivity literature, relatively old individuals showed significantly greater increases in ambulatory diastolic blood pressure compared with younger individuals when dealing with daily stressors. However, results also revealed that relatively old individuals reported less of an increase in negative affect during daily stress compared with their younger counterparts. The results of this study are consistent with the age-related increase in cardiovascular risk but highlight the complex links between stress and different facets of the aging process.     

The associative-memory basis of cognitive skill learning: adult age differences

It has been established that memorizing common problems and their solutions underlies cognitive skill development, and that there are substantial age deficits in the rate of this learning. In a between-groups design, the authors compared learning rates for the same set of problems in skill (SK) training and paired-associate (PA) training. The authors found main effects due to condition (PA problems were acquired earlier) and to age (older adults' learning was delayed), but no condition-by-age interaction. The authors concluded that the age deficit in SK can be accounted for by the age deficit in associative memory; no further explanation is needed. The authors also analyzed fast and slow retrieves in SK and PA, and found that the frequency of fast retrieves did not differ in the two conditions. The overall advantage of PA was due to the occurrence of slow retrieves, which were absent in SK presumably because the skill algorithm displaces slow, explicit memory search in SK, but not fast, familiarity-based retrieval.     

Decomposing adult age differences in symbol arithmetic

A componential analysis was conducted to determine the locus of adult age differences in symbol arithmetic. Measures of the duration of two proposed components, substitution of digits for symbols and the addition or subtraction of the digits resulting from these substitutions, were obtained from 52 young adults and 52 older adults. Tests of working memory, perceptual speed, motor speed, and associative learning were also administered to all subjects. The results were most consistent with an interpretation postulating that the speed of many different cognitive processes decreases with increased age. Considerable age-related variance remained in the measures of symbol arithmetic performance after statistical control of working memory and associative learning performance, casting doubt on alternative hypotheses of the source of age-related differences in this task.     

Working-memory mediationof adult age differences in integrativereasoning

Three research methods were used to investigate the hypothesized mediational influence of working memory on age-related differences in integrative reasoning. Results from all three procedures were consistent with the hypothesis because (1) statistical control of an index of working memory attenuated the age differences in reasoning accuracy, (2) young adults were more accurate than older adults in a measure reflecting the preservation of information during processing, and (3) young adults performing the task with a concurrent memory load exhibited a qualitative pattern of performance similar to that of older adults performing the task without a concurrent memory load.     

The influence of expertise and task factors on age differences in pilot communication

The influence of expertise and task factors on age differences in a simulated pilot-Air Traffic Control (ATC) communication task was examined. Young, middle-aged, and older pilots and nonpilots listened to ATC messages that described a route through an airspace, during which they referred to a chart of this airspace. Participants read back each message and then answered a probe question about the route. It was found that pilots read back messages more accurately than nonpilots, and younger participants were more accurate than older participants. Age differences were not reduced for pilots. Pilots and younger participants also answered probes more accurately, suggesting that they were better able to interpret the ATC messages in terms of the chart in order to create a situation model of the flight. The findings suggest that expertise benefits occur for adults of all ages. High levels of flying experience among older pilots (as compared with younger pilots) helped to buffer age-related declines in cognitive resources, thus providing evidence for the mediating effects of experience on age differences.     

The source of adult age differences in event-based prospective memory: a multinomial modeling approach

Event-based prospective memory involves remembering to perform an action in response to a particular future event. Normal younger and older adults performed event-based prospective memory tasks in 2 experiments. The authors applied a formal multinomial processing tree model of prospective memory (Smith & Bayen, 2004) to disentangle age differences in the prospective component (remembering that you have to do something) and the retrospective component (remembering when to perform the action) of prospective memory performance. The modeling results, as well as more traditional analyses, indicate age differences in the resource-demanding prospective component.     

Adult age differences in interference from a prospective-memory task: a diffusion model analysis

People often slow down their ongoing activities when they must remember an intended action, known as the cost or interference effect of prospective memory (PM). Only a few studies have examined adult age differences in PM interference, and the specific reasons underlying such differences are not well understood. The authors used a model-based approach to reveal processes underlying PM interference and age differences in these processes. Older and younger adults first performed a block of an ongoing lexical decision task alone. An embedded event-based PM task was added in a second block. Simultaneously accounting for the changes in response time distributions and error rates induced by the PM task, Ratcliff’s (Psychological Review 85:59–108, 1978) diffusion model was used to decompose the nonlinear combination of speed and accuracy into psychologically meaningful components. Remembering an intention not only reduced processing efficiency in both age groups, but also prolonged peripheral nondecision times and induced response cautiousness. Overall, the findings suggest that there are multiple, but qualitatively similar factors underlying PM task interference in both age groups.     

Classical conditioning and extinction of human systolic blood pressure

Fifty-five male and female undergraduates underwent 3 sessions of conditioning and one of extinction. Shock (UCS) occurred intermittently during light-on (CS+) and never in light-off (CS-). Results showed that (1) pressure in CS+ was significantly higher than CS-throughout all sessions; (2) within session adaptation was significantly retarded while incoming pressure levels did not adapt across sessions; (3) conditioned effects persisted 6 months after the last shock session; (4) verbal information as to non-appearance of shock significantly dropped pressure levels and reduced the discriminative light effect; (5) the post-shock unconditioned pressure response was a peak rise at 52 seconds, then a decrease which stabilized to the pre-shock level at 2 minutes. Pavlovian control of blood pressure was demonstrated and the present methodology offers an explicit procedure for further laboratory exploration.     

Bilingualism and adult differences in inhibitory mechanisms: evidence from a bilingual stroop task

The present investigation examined the functioning of inhibitory mechanisms in younger and older bilinguals using a bilingual version of the Stroop test. The study predicted different patterns of age related decline in inhibitory mechanisms (inter- and intralingual interference) in bilinguals depending on their level of proficiency. Consistent with expectations, older bilinguals were slower when they responded in their non-dominant language. Furthermore, older unbalanced bilinguals showed greater interlingual interference when they responded with their second language to visual stimuli written in their dominant language. Balanced bilinguals showed equivalent interference effects between all conditions. These findings suggest that manipulating two languages may enhance the efficiency of inhibitory mechanisms.     

Absence of adult age differences in forgetting in the Brown-Peterson Task

Despite some recent evidence to the contrary, no reliable age differences in proactive interference (PI) or retroactive interference (RI) were found in a cross-sectional study of adults aged 18-29 and 63-75. Individual memory span was used as the list length in the Brown-Peterson Task in order to achieve stimulus equivalence of memory loads across individuals and age groups. Data from rehearsers were excluded from the analyses in order to isolate age differences in passive forgetting processes from those in rehearsal. PI was manipulated by presenting categorized or uncategorized memory lists. RI was manipulated, holding distractor task difficulty constant, by using words or tones in a signal detection distractor task. It is concluded that age differences are minimal to nonexistent in passive RI-related processes such as decay and perturbation and in passive PI-related processes such as set effects in semantic encoding.     

Dual-task performance as a function of adult age and task complexity

A dual-task procedure was used to examine capacity demands of letter-matching in younger and older adults. Older subjects generally were slower on both tasks than were younger adults, but this difference was especially pronounced for the late stages of category matching, suggesting that retrieval and comparison of category information is particularly demanding for older adults.     

Outsourcing cognitive control to the environment: Adult age differences in the use of task cues

When an initial phase of cued task switching is followed by a phase of single-task trials, older adults show difficulties changing to the more efficient single-task mode of processing (Mayr & Liebscher, 2001). In Experiment 1, we show that these costs follow older adults’ continued tendency to inspect task cues even though these provide no new information. In Experiment 2, we included a condition in which task cues were eliminated from the display after the task-switching phase. In this condition, older adults behaved the same as younger adults, suggesting that the presence of the task cue is critical for observing age differences while switching from a “high-control” to a “low-control” mode of processing. We discuss our results in terms of a life-span shift with regard to the reliance on internal versus external sources of information under conditions of high-control demands.     

Recollection and familiarity in recognition memory: adult age differences and neuropsychological test correlates

Dual process theories account for age-related changes in memory by proposing that old age is associated with deficits in recollection together with invariance in familiarity. The authors evaluated this proposal in recognition by examining recollection and familiarity estimates in young and older adults across 3 process estimation methods: inclusion/exclusion, remember/know, and receiver operating characteristics (ROC). Consistent with a previous literature review (Light, Prull, LaVoie, & Healy, 2000), the authors found age invariance in familiarity when process estimates were derived from the inclusion/exclusion method, but the authors found age differences favoring the young when familiarity estimates were derived from the remember/know and ROC methods. Recollection estimates were lower for older adults in all 3 methods. Recollection and familiarity had variable relationships with frontal- and temporal-lobe measures of neuropsychological functioning in older adults, depending on which method was used to generate process estimates. These data suggest that although recollection deficits appear to be the rule in aging, not all estimates of familiarity show age invariance.     

Wisdom-related knowledge in a life review task: age differences and the role of professional specialization.

The study adopts life review as an avenue to access wisdom-related knowledge and examines the contribution of age and type of professional specialization to individual differences in wisdom-related knowledge. Women from 2 age groups/cohorts (young, M = 32 years; old, M = 71 years) and different professional specializations (human services vs. nonhuman services) were asked to think aloud about the life review of a fictitious woman who was either young or old. Verbal protocols were scored on 5 wisdom-related criteria: factual and procedural knowledge about life, life-span contextualism, relativism of values, recognition, and management of uncertainty. Three major findings emerged. First, human-services professionals outperformed the control group. Second, old adults performed as well as young adults. Third, for older adults wisdom-related performance was enhanced by the match between their own age and the age of the fictitious character.     

Activity duration and adult age differences in memory for activity performance

Young and elderly subjects performed a series of activities that varied in the duration of their performances (45 s, 90 s, and 180 s). Duration was found to have a negligible effect on the subsequent recall of the activities and on the magnitude of the age deficit in recall. Operationalization of the program for performing an activity seems essential for establishing a memory trace of that activity's performance, but the duration of performing that activity seems to yield no further enhancement of that trace.     

Examining age differences in performance of a complex information search and retrieval task.

This study examined age differences in performance of a complex information search and retrieval task by using a simulated real-world task typical of those performed by customer service representatives. The study also investigated the influence of task experience and the relationships between cognitive abilities and task performance. One hundred seventeen participants from 3 age groups, younger (20-39 years). middle-aged (40-59 years), and older (60-75 years), performed the task for 3 days. Significant age differences were found for all measures of task performance with the exception of navigational efficiency and number of problems correctly navigated per attempt. There were also effects of task experience. The findings also indicated significant direct and indirect relations between component cognitive abilities and task performance.