Aging, Neuropsychology, and Cognition最新文献

Working memory (WM), the capacity to temporarily hold and manipulate information, is evaluated using the span paradigm, which consists of forward and backward recall tasks to assess storage and manipulation, respectively. In accordance with the dedifferentiation theory, which suggests that different cognitive abilities compensate for the decline of others during the aging process, the current study aimed to examine whether fluid intelligence mediates the relationship between forward and backward recall across verbal, visuospatial, and tactile modalities while including age as a moderator. A total of 106 healthy older adults aged 60-89 years underwent the Digit Span, Visuospatial Span, Tactual Span, and Raven Colored Progressive Matrices Test. We found positive correlations between forward and backward recall in all three span tasks. Additionally, the tactile and visuospatial moderated mediation models were significant, whereas the tactile model seemed more robust. However, the verbal model was found to be non-significant. These findings suggest that storage and manipulation are associated across different modalities, but fluid intelligence becomes a more significant factor as age progresses, thus compensating for WM decline. Nevertheless, this pattern varies between modalities, indicating a WM modality-specific differentiation dependent on the cognitive load. Our findings have implications for understanding cognitive aging processes and theoretical frameworks concerning WM.

Theory of mind is a core social cognitive ability, and declines over the lifespan. Prior work examining the mechanisms underlying older adults' theory of mind deficits has yielded heterogenous results. One reason for this might be a general reliance on static, rather than dynamic, stimuli. Because dynamic measures may best capture everyday theory of mind engagement, the current study examined whether executive function and/or episodic memory - the primary mechanisms examined in prior work - predicted older adults' static and dynamic theory of mind performance. In Study 1, 153 older adults completed traditional static measures of theory of mind (false belief task, Reading the Mind in the Eyes) and a dynamic theory of mind measure that captured multiple domains of theory of mind (e.g. inferring beliefs, understanding emotions). They also completed comprehensive measures of executive function and episodic memory. Episodic memory, but not executive function, predicted theory of mind performance across tasks. In Study 2, 124 different older adults completed two novel dynamic tasks, and the same cognitive measures from Study 1. The first dynamic task was similar to the Study 1, but was relatively unfamiliar. In the second task, older adults made continuous (e.g. dynamic) awkwardness ratings while watching a video. This task reduces ceiling effects, a frequent limitation of theory of mind research. Replicating the results in Study 1, episodic memory, but not executive function, predicted older adults' performance on both tasks. Together, these findings suggest that episodic memory ability predicts older adults' static and dynamic theory of mind performance.

Having a sense of purpose in life predicts better maintenance of cognitive function in older adulthood and reduced risk of mild cognitive impairment (MCI) and dementia. However, little research has examined its influence on the rate of cognitive decline and length of cognitive healthspan. This study evaluated the role of sense of purpose on the risk and timing of transitions between normal cognition, MCI, and dementia. Older adults from the Memory and Aging Project (MAP; n = 1821) and the Health and Retirement Study (HRS; n = 10,542) were followed annually for 19 years and biennially for 12 years, respectively. Multistate survival models assessed whether sense of purpose predicted transitions across normal cognition, MCI, dementia, and death. More purposeful older adults had lower risk of developing MCI (HR = 0.82 in MAP; HR = 0.93 in HRS), higher likelihood of cognitive improvement, and longer cognitively healthy life expectancies. Results suggest sense of purpose may extend the cognitive healthspan.

We investigated age-related differences in serial and strategic processing during the encoding and retrieval of high-value words. Younger and older adults were presented with word triads positioned left, center, and right, with one word being more valuable than the others. In Experiment 1, younger adults more effectively recalled the middle, high-value word, demonstrating enhanced strategic memory. Younger adults were more likely to initiate recall with a high-value word whereas older adults were equally likely to initiate recall with a left and high-value word. Additionally, older adults were more likely to recall words in their presented order while younger adults strategically recalled successive high-value words. However, both age groups demonstrated strategic processing in Experiments 2 and 3, even without prior knowledge of the high-value word's location. Thus, serial and strategic processing may differ based on age and task demands, but strategic processing is preserved in older adults in certain contexts.

Aging is associated with cognitive changes, even in the absence of brain pathology. This study aimed to determine if meditation training, by comparison to active and passive control groups, is linked to changes in the perception of cognitive functioning in older adults. One hundred thirty-four healthy older participants from the Age-Well Randomized Clinical Trial were included: 45 followed a meditation training, 45 a non-native language training and 44 had no intervention. Subjective cognition was assessed at baseline and following the 18-month intervention period. Perception of attentional efficiency was assessed using internal and external Attentional Style Questionnaire (ASQ) subscale scores. Perception of global cognitive capacities was measured via the total score of Cognitive Difficulties Scale (CDS). Deltas ([posttest minus pretest scores]/standard deviation at pretest) were calculated for the analyses. Generalized mixed effects models controlling for age, sex, education and baseline scores revealed that meditation training decreased the vulnerability score toward external distractors measured by the ASQ compared to non-native language training. However, no between-groups differences on ASQ internal or CDS total scores were observed. Results suggest a beneficial effect of meditation practice on perceived management of external distracting information in daily life. Meditation training may cultivate the ability to focus on specific information (e.g., breath) and ignore stimulation from other kinds of stimuli (e.g., noise).

Estrogen exposure during menstrual years has been associated with late-life neuroprotection. We explored the presence of an age-sensitive menarche window for cognition in old age and the impact of socioeconomic status and education. We compared neuropsychological performance of 1082 older women [Mean^AGE = 72.69 (5.48)] with menarche in childhood, early-, mid-, and late-adolescence and dementia prevalence, severity, and type, including the effects of education and socioeconomic status. Adjusting for covariates, menarche at 11-14 years of age was associated with better memory, executive and global cognitive functioning in old age, and stronger positive effects of education and socioeconomic status on cognition than those with menarche at 15-17 years. We found a critical age window for the neuroprotective effects of estrogens during early adolescence, putting women with later menarche at higher risk for cognitive decline. Effects of socioeconomic status and education in adulthood should be a focus of future research.

This study investigated the impact of language learning in comparison to other complex learning activities on cognitive functioning and psychosocial well-being in cognitively healthy, community-dwelling older adults. In a randomized controlled trial, 43 Dutch functionally monolinguals aged 65-78 completed a three-month English course (n = 15), music training (n = 13), or a lecture series (n = 15). Cognitive functioning (global cognition, cognitive flexibility, episodic memory, working memory, verbal fluency, and attention) and psychosocial well-being were assessed before and immediately after the intervention, and at a four-month follow-up. The language learners significantly improved on episodic memory and cognitive flexibility. However, the magnitude of cognitive change did not significantly differ between the language learning and music training conditions, except for a larger positive change in cognitive flexibility for the language learners from pretest to follow-up. Our results suggest that language learning in later life can improve some cognitive functions and fluency in the additional language, but that its unique effects seem limited.

Positive affect has been shown to promote task-switching performance in healthy young adults. Given the well-documented age-related decline in executive functioning, we asked whether induced positive affect also helps to improve task-switching performance in older adults. Sixty-eight younger and older adults performed a switching task before and after they had watched cartoon clips (positive affect group) or documentaries (neutral affect group). Positive affect was associated with reduced error rates across all trial types in both age groups. In older adults, the increase in accuracy came at the expense of slower response times for task-switch trials, resulting in greater switch costs. This pattern of findings is inconsistent with the popular notion that positive affect supports greater cognitive flexibility. Instead, positive affect may trigger adjustments in response control settings - such as a shift in the speed-accuracy trade-off toward more cautious responding - depending on the experienced level of task difficulty.

This study examined age differences in effort devoted to completing cognitively demanding tasks. Fifty-two younger adults ages 18-30 years (M_age = 21.19) and 57 older adults ages 61-93 years (M_age = 76.56) completed a series of memory tests. Following each test, participants rated the test's difficulty and had their blood pressure measured. Effort was indexed by systolic blood pressure response (SBP-R) with greater increases in SBP-R reflecting more effort. Multilevel modeling was used to examine age differences in the intraindividual association between trial-level subjective task difficulty and trial-level effort. Results showed that increases in task difficulty were significantly related to decreases in SBP-R for the older but not younger adults, suggesting the older adults disengaged from the tests they perceived as highly difficult. Findings support Selective Engagement Theory (Hess, 2014), which suggests the perceived cognitive costs of completing difficult tasks may reduce older adults' motivation to engage in the tasks.

Navigational abilities decline with age, but the cognitive underpinnings of this cognitive decline remain partially understood. Navigation is guided by landmarks and self-motion cues, that we address when estimating our location. These sources of spatial information are often associated with noise and uncertainty, thus posing a challenge during navigation. To overcome this challenge, humans and other species rely on navigational cues according to their reliability: reliable cues are highly weighted and therefore strongly influence our spatial behavior, compared to less reliable ones. We hypothesize that older adults do not efficiently weigh spatial cues, and accordingly, the reliability levels of navigational cues may not modulate their spatial behavior, as with younger adults. To test this, younger and older adults performed a virtual navigational task, subject to modified reliability of landmarks and self-motion cues. The findings revealed that while increased reliability of spatial cues improved navigational performance across both age groups, older adults exhibited diminished sensitivity to changes in landmark reliability. The findings demonstrate a cognitive mechanism that could lead to impaired navigation abilities in older adults.