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Introduction: Developing realistic expectations of future old age constitutes an adaptational process which facilitates the anticipation of and adjustment to challenges, such as relocation to a nursing home. Developing such expectations might minimize the negative impacts of relocation. This pre-registered study examined (1) to which extent lower levels and declines in health (i.e., functional limitations and self-rated health) and life satisfaction before relocation were associated with higher levels and increases in expectations to relocate and (2) to which extent higher expectations to relocate were associated with more positive changes in health and life satisfaction after relocation. Methods: Using data from the Health and Retirement Study (HRS; 2006–2018), we selected older adults (aged 65 years and older) who relocated to a nursing home. We used latent growth curve models to assess the longitudinal links between self-reported measures of health, life satisfaction, and expectations to relocate to a nursing home from up to 7 years before (n = 1,048) until up to 5 years after relocation (n = 307). Results: As hypothesized, more functional limitations and lower self-rated health were related to higher expectations of relocation. Surprisingly, changes in expectations to relocate were not related to changes in health and life satisfaction before relocation. Moreover, expectations to relocate were not associated with changes in health and life satisfaction after relocation. Conclusion: The absence of a link between expectations to relocate to a nursing home with changes in health and well-being suggests that these expectations did not constitute adaptational processes before or after this transition. [ABSTRACT FROM AUTHOR]

Personality traits have been reported to predict difficulties in performing instrumental activities of daily living (IADL) in old age, such as preparing meals or shopping. However, little is known about the reciprocal effects on personality. In this study, we examined bidirectional relationships between personality traits and the capacity to perform IADL using four waves of longitudinal data from 3540 older adults (aged 65 years and older) from the Health and Retirement Study. We applied a random-intercept cross-lagged panel model to separate between- and within-person effects across time and compared it to a traditional cross-lagged panel model. At the between-person level, higher neuroticism and lower conscientiousness were associated with more IADL limitations. Within individuals across time, increases in neuroticism and decreases in conscientiousness and extraversion were associated with increases in IADL limitations 4 years later. In contrast, increases in IADL limitations only predicted increases in neuroticism and decreases in extraversion. These results indicate that some personality traits affect and are affected by limitations in functional capacities in old age. Results of the within-person model build a strong foundation for future personality interventions as a pathway to maintain high functioning in old age. [ABSTRACT FROM AUTHOR]

The neural correlates of encoding mode , or the state of forming new memory episodes, have been found to change with age and mnemonic training. However, it is unclear whether neural correlates of encoding success , termed subsequent-memory (SM) effects, also differ by age and mnemonic skill. In a multi-session training study, we investigated whether SM effects are altered by instruction and training in a mnemonic skill, and whether such alterations differ among children, younger adults, and older adults. Before and after strategy training, fMRI data were collected while participants were memorizing word pairs. In all age groups, participants receiving training showed greater performance gains than control group participants. Analysis of task-relevant regions showed training-induced reductions in SM effects in left frontal regions. Reductions in SM effects largely generalized across age and primarily reflected greater training-induced activation increases for omissions than for remembered items, indicating that training resulted in more consistent use of the mnemonic strategy. The present results reveal no major age differences in SM effects in children, younger adults, and older adults. [ABSTRACT FROM AUTHOR]

Aging is typically related to changes in brain and cognition, but the aging process is heterogeneous and differs between individuals. Recent research has started investigating the influence of cognitive and physical training on cognitive performance, functional brain activity, and brain structure in old age. The functional relevance of neural changes and the interactions among these changes following interventions is still a matter of debate. Here we selectively review research on structural and functional brain correlates of training-induced performance changes in healthy older adults and present exemplary longitudinal intervention studies sorted by the type of training applied (i.e., strategy-based training, process-specific training, and physical exercise). Although many training studies have been conducted recently, within each task domain, the number of studies that used comparable methods and techniques to assess behavioral and neural changes is limited. We suggest that future studies should include a multimodal approach to enhance the understanding of the relation between different levels of brain changes in aging and those changes that result from training. Investigating inter-individual differences in intervention-induced behavioral and neuronal changes would provide more information about who would benefit from a specific intervention and why. In addition, a more systematic examination of the time course of training-related structural and functional changes would improve the current level of knowledge about how learning is implemented in the brain and facilitate our understanding of contradictory results. [ABSTRACT FROM AUTHOR]

Abstract: Working memory (WM) functioning declines in old age. Due to its impact on many higher-order cognitive functions, investigating whether training can modify WM performance has recently been of great interest. We examined the relationship between behavioral performance and neural activity following five weeks of intensive WM training in 23 healthy older adults (M =63.7years). 12 participants received adaptive training (i.e. individually adjusted task difficulty to bring individuals to their performance maximum), whereas the others served as active controls (i.e. fixed low-level practice). Brain activity was measured before and after training, using fMRI, while subjects performed a WM task under two difficulty conditions. Although there were no training-related changes in WM during scanning, neocortical brain activity decreased post training and these decreases were larger in the adaptive training group than in the controls under high WM load. This pattern suggests intervention-related increases in neural efficiency. Further, there were disproportionate gains in the adaptive training group in trained as well as in non-trained (i.e. attention, episodic memory) tasks assessed outside the scanner, indicating the efficacy of the training regimen. Critically, the degree of training-related changes in brain activity (i.e. neocortical decreases and subcortical increases) was related to the maximum gain score achieved during the intervention period. This relationship suggests that the decreased activity, but also specific activity increases, observed were functionally relevant. [Copyright &y& Elsevier]

Abstract: LMX1A is a transcription factor involved in the development of dopamine (DA)-producing neurons in midbrain. Previous research has shown that allelic variations in three LMX1A single nucleotide polymorphisms (SNPs) were related to risk of Parkinson''s disease (PD), suggesting that these SNPs may influence the number of mesencephalic DA neurons. Prompted by the established link between striatal DA functions and working memory (WM) performance, we examined two of these SNPs in relation to the ability to benefit from 4 weeks of WM training. One SNP (rs4657412) was strongly associated with the magnitude of training-related gains in verbal WM. The allele linked to larger gains has previously been suggested to be associated with higher dopaminergic nerve cell density. No differential gains of either SNP were observed for spatial WM, and the genotype groups were also indistinguishable in tests of attention, interference control, episodic memory, perceptual speed, and reasoning for both SNPs. This pattern of data is in agreement with previous findings from our group, suggesting that cognitive effects of DA-related genes may be more easily detected in a training context than for single-assessment performance scores. [Copyright &y& Elsevier]

Abstract: Dopamine (DA) is implicated in working memory (WM) functioning. Variations in the DA transporter (DAT1) gene (SLC6A3) regulate DA availability in striatum. Compared to DAT1 9/10-repeat carriers, homozygosity of the DAT1 10-repeat allele has been related to less active dopaminergic pathways. A group of younger adults received 4 weeks of computerized adaptive training on several WM tasks. All participants improved their performance as a function of training. However, DAT1 9/10-repeat carriers showed larger training-related gains than DAT1 10-repeat carriers in visuospatial WM. By contrast, the two groups were indistinguishable in baseline WM performance as well as in a variety of tasks assessing different cognitive abilities. This pattern of results provides novel evidence that WM plasticity is a more sensitive indicator of DAT1 gene-related cognitive differences than single-assessment performance scores. [Copyright &y& Elsevier]

The authors examined life-span differences in the maintenance of skilled episodic memory performance by assessing 100 individuals (10-11, 12-13, 2 1-26, and 66-79 years old) 11 months after termination of an intensive multisession mnemonic training program (Y. Brehmer, S-C. Li, V. Müller, T. von Oertzen, & U. Lindenberger, 2007). Skill maintenance was tested in 2 follow-up sessions, the first without and the second with mnemonic reinstruction. Younger and older adults' average performance levels were stable across time. In contrast, both younger and older children's memory performance improved beyond originally attained levels. Older adults' performance improved from the first to the second follow-up session, presumably profiting from instruction-induced skill reactivation. Results suggest that (a) skill maintenance is largely intact in healthy older adults, (b) older adults need environmental support to fully reactivate their former skill levels (cf. F. I. M. Craik, 1983), and (c) children adapt a skill learned 11 months ago to their increasing cognitive capabilities. [ABSTRACT FROM AUTHOR]

Background: To study how event-related brain potentials (ERPs) and underlying cortical mechanisms of selective attention change from childhood to old age, we investigated lifespan age differences in ERPs during an auditory oddball task in four age groups including 24 younger children (9-10 years), 28 older children (11-12 years), 31 younger adults (18-25), and 28 older adults (63-74 years). In the Unattend condition, participants were asked to simply listen to the tones. In the Attend condition, participants were asked to count the deviant stimuli. Five primary ERP components (N1, P2, N2, P3 and N3) were extracted for deviant stimuli under Attend conditions for lifespan comparison. Furthermore, Mismatch Negativity (MMN) and Late Discriminative Negativity (LDN) were computed as difference waves between deviant and standard tones, whereas Early and Late Processing Negativity (EPN and LPN) were calculated as difference waves between tones processed under Attend and Unattend conditions. These four secondary ERP-derived measures were taken as indicators for change detection (MMN and LDN) and selective attention (EPN and LPN), respectively. To examine lifespan age differences, the derived differencewave components for attended (MMN and LDN) and deviant (EPN and LPN) stimuli were specifically compared across the four age groups. Results: Both primary and secondary ERP components showed age-related differences in peak amplitude, peak latency, and topological distribution. The P2 amplitude was higher in adults compared to children, whereas N2 showed the opposite effect. P3 peak amplitude was higher in older children and younger adults than in older adults. The amplitudes of N3, LDN, and LPN were higher in older children compared with both of the adult groups. In addition, both P3 and N3 peak latencies were significantly longer in older than in younger adults. Interestingly, in the young adult sample P3 peak amplitude correlated positively and P3 peak latency correlated negatively with performance in the Identical Picture test, a marker measure of fluid intelligence. Conclusion: The present findings suggest that patterns of event-related brain potentials are highly malleable within individuals and undergo profound reorganization from childhood to adulthood and old age. [ABSTRACT FROM AUTHOR]

Memory plasticity, or the ability to improve one's memory performance through instruction and training, is known to decline during adulthood. However, direct comparisons among middle childhood, adulthood, and old age are lacking. The authors examined memory plasticity in an age-comparative multisession training study. One hundred and eight participants ages 9-10, 11-12, 20-25, and 65-78 years learned and practiced an imagery-based mnemonic technique to encode and retrieve words by location cues. Individuals of all ages were able to acquire and optimize use of the technique. Older adults and children showed similar baseline performance and improvement through mnemonic instruction. However, in line with tenets from life-span psychology (P. B. Baltes, 1987), children profited more from mnemonic practice and reached higher levels of final performance than did older adults. [ABSTRACT FROM AUTHOR]

Abstract: Developmental plasticity is the key mechanism that allows humans and other organisms to modify and adapt to contextual and experiential influences. Thus, reciprocal co-constructive interactions between behavioral and neuronal plasticity play important roles in regulating neurobehavioral development across the life span. This review focuses on behavioral and neuronal evidence of lifespan differences in associative memory plasticity and plasticity of the functional organization of cognitive and cortical processes, as well as the role of the dopaminergic system in modulating such plasticity. Special attention is given to neurocomputational models that help exploring lifespan differences in neuromodulation of neuronal and behavioral plasticity. Simulation results from these models suggest that lifespan changes in the efficacy of neuromodulatory mechanisms may shape associative memory plasticity and the functional organization of neurocognitive processes by affecting the fidelity of neuronal signal transmission, which has consequences for the distinctiveness of neurocognitive representations and the efficacy of distributed neural coding. [Copyright &y& Elsevier]

While psychopathy has been a topic of interest in the psychological field for a long time, it is still unclear which developmental factors are related to its onset. Theories have suggested that experiencing trauma in childhood may contribute to the development of psychopathic traits. Experiencing trauma may also contribute to the development of an insecure attachment style, which in turn might cause the emergence of psychopathic traits. The current study investigated links between experiencing childhood trauma and the three psychopathy domains of the Extended Levenson Self-Report Psychopathy scale (E-LSRP; Egocentricity, Callousness, and Antisocial), and whether these links were mediated by the four insecure attachment dimensions of the Attachment Style Questionnaire (ASQ; Need for Approval, Preoccupation with Relationships, Relationships as Secondary, and Discomfort with Closeness), in a large sample of non-clinical participants (N = 2023, Mage = 32.7, 70.0% female). The results suggested that Relationships as Secondary, but not Discomfort with Closeness, positively mediated the relationship between childhood trauma and the three domains of psychopathy, while Need for Approval negatively mediated this relationship. Preoccupation with Relationships was a significant mediator in the links between childhood trauma and both the Egocentricity and Antisocial domains, but not the Callousness domain. The current findings suggested that there might be both shared and differential mechanisms linking childhood trauma and psychopathic traits through insecure attachment styles. These findings can guide further investigations in longitudinal research. [ABSTRACT FROM AUTHOR]

Older adults show relatively minor age-related decline in memory for single items, while their memory for associations is markedly reduced. Inter-individual differences in memory function in older adults are substantial but the neurobiological underpinnings of such differences are not well understood. In particular, the relative importance of inter-individual differences in the medio-temporal lobe (MTL) and the lateral prefrontal cortex (PFC) for associative and item recognition in older adults is still ambiguous. We therefore aimed to first establish the distinction between inter-individual differences in associative memory (recollection-based) performance and item memory (familiarity-based) performance in older adults and subsequently link these two constructs to differences in cortical thickness in the MTL and lateral PFC regions, in a latent structural equation modelling framework. To this end, a sample of 160 older adults (65–75 years old) performed three intentional item-associative memory tasks, of which a subsample (n ​= ​72) additionally had cortical thickness measures in MTL and PFC regions of interest available. The results provided support for a distinction between familiarity-based item memory and recollection-based associative memory performance in older adults. Cortical thickness in the ventro-medial prefrontal cortex was positively correlated with associative recognition performance, above and beyond any relationship between item recognition performance and cortical thickness in the same region and between associative recognition performance and brain structure in the MTL (parahippocampus). The findings highlight the relative importance of the ventromedial prefrontal cortex in allowing for intentional recollection-based associative memory functioning in older adults. • Latent structural equation modeling supports dual-process theories of recognition. • Cortical thickness in the ventro-lateral PFC is linked to associative recognition. • No link between ventro-lateral PFC thickness and item recognition. • Medial-temporal lobe and associative recognition not linked in healthy older adults. [ABSTRACT FROM AUTHOR]

\n The grandparent role has been often described as one of the most fulfilling aspects of older age. Yet, no longitudinal studies investigated the effect of the transition to grandparenthood on older adults’ sense of purpose and meaning in life. In this pre-registered study, we investigated the effect of becoming a first-time grandparent and a first-time caregiving grandparent on changes in sense of purpose and meaning in life. We used data from the Health and Retirement Study (HRS) and English Longitudinal Study of Ageing (ELSA), covering up to 12 years around the transition (N HRS = 843, N ELSA = 587). To disentangle potential grandparenthood effects from age-related developmental changes, we used propensity score matching to compare grandparents to matched non-grandparents. Using latent change score models, we only found increases in sense of purpose in the years leading up to the transition, but not afterwards. No consistent findings of mean-level changes were observed in the control groups. Thus, our findings suggest that becoming a (caregiving) grandparent does not necessarily contribute to higher meaning and sense of purpose in life than before or compared to non-grandparents.Older adults often report that being a grandparent is one of the most fulfilling roles of older age. However, there are no studies to investigate how older adults’ sense of purpose and meaning in life changes over time when they first become grandparents. Similarly, no past research has investigated how the two constructs change when first-time grandparents start to provide care for their grandchildren for the first time. In this study, we use data from two large population studies (Health and Retirement Study and English Longitudinal Study of Ageing; NHRS = 843, NELSA = 587 ) covering up to 12 years to see if newly grandparents increase in sense of purpose and meaning in life during the transition to (active) grandparenthood. To make sure that any potential effects are not due to life events or changes that normally take place during old age, we compared grandparents to older adults that were not (yet) grandparents, or did not have children, but were similar to our target group (i.e., grandparents) with respect to other characteristics—for example, age, gender, and health status. We did not find evidence for any change in sense of purpose and meaning in life after older adults become grandparents, but only in the years leading up to the transition to grandparenthood. For the groups of non-grandparents, we did not find any notable differences in how sense of purpose and meaning in life changed during the study period compared to the groups of grandparents. Starting to provide grandchildren as a first-time grandparent also did not lead to any changes in sense of purpose and meaning in life. [ABSTRACT FROM AUTHOR]

Foreign language learning in older age has been proposed as a promising avenue for combatting age-related cognitive decline. We tested this hypothesis in a randomized controlled study in a sample of 160 healthy older participants (aged 65-75 years) who were randomized to 11 weeks of either language learning or relaxation training. Participants in the language learning condition obtained some basic knowledge in the new language (Italian), but between-groups differences in improvements on latent factors of verbal intelligence, spatial intelligence, working memory, item memory, or associative memory were negligible. We argue that this is not due to either poor measurement, low course intensity, or low statistical power, but that basic studies in foreign languages in older age are likely to have no or trivially small effects on cognitive abilities. We place this in the context of the cognitive training and engagement literature and conclude that while foreign language learning may expand the behavioral repertoire, it does little to improve cognitive processing abilities. (PsycINFO Database Record (c) 2020 APA, all rights reserved). [ABSTRACT FROM AUTHOR]

The engagement in cognitively stimulating activities has been found to be associated with slower rates of cognitive decline in old age. In which type of activities people engage in may depend on their personality traits, which thus might have an impact on later cognitive fitness. To study these potential links, we examined the associations between Neuroticism, Extraversion, and Openness; different types of leisure activities (e.g., social, mental, physical); and cognitive ability levels and decline in older adults. Analyses were based on a sample of young–old (60–72 years old; n = 1,609) and old–old (78 years or older; n = 1,085) adults from the Swedish National Study on Aging and Care in Kungsholmen, who participated in up to five repeated measurements of cognitive abilities spanning 12 years. We used latent growth curve models to estimate cognitive levels and decline, as well as the correlations with initial personality trait levels and leisure activity engagement. In both groups, lower Neuroticism, higher Extraversion, and higher Openness levels were moderately associated with stronger engagement in all types of activities. Lower Neuroticism, higher Extraversion, and a more activity lifestyle were weakly to moderately associated with slower cognitive decline in the old–old age group. There, personality traits and activities explained 9.3% of the variance in cognitive decline after controlling for age, sex, education, and chronic diseases (which explained 9.0%). Taken together, this study provides further evidence for the connection between personality traits, activity engagement, and later cognitive decline in old age. Public Significance Statement: This study suggests that older adults (78+ years old) who are more extraverted, open, and emotionally stable have a more active lifestyle and show a slower cognitive decline in the following years. Independent of the personality traits, an active social, mental, or physical lifestyle was also associated with a slower cognitive decline for this age group. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that engagement in leisure activities is associated with favorable trajectories of cognitive aging, but little is known about brain changes related to both activities and cognition. White matter microstructure shows experience-dependent plasticity and declines in aging. Therefore, we investigated the role of change in white matter microstructure in the activities-cognition link. We used repeated assessments of engagement, perceptual speed, and white matter microstructure (probed with diffusion tensor imaging) in a population-based sample of individuals over 80 years without dementia ( n = 442, M age = 85.1; n = 70 for diffusion tensor imaging; 2 occasions 3 years apart). Using multivariate latent change modeling, we observed positive correlations among changes in predominantly social activities, white matter microstructure, and perceptual speed. Interindividual differences in change in white matter microstructure statistically accounted for the association between change in leisure activities and change in perceptual speed. However, as analyses are based on observational data from 2 measurement occasions, causality remains unclear. [ABSTRACT FROM AUTHOR]

Abstract: The structural and functional brain circuitries supporting episodic memory undergo profound reorganization in childhood and old age. We propose a two-component framework that combines and integrates evidence from child development and aging. It posits that episodic memory builds on two interacting components: (a) the strategic component, which refers to memory control operations, and (b) the associative component, which refers to mechanisms that bind different features of a memory episode into a compound representation. We hypothesize that: (a) children''s difficulties in episodic memory primarily originate from low levels of strategic operations, and reflect the protracted development of the prefrontal cortex (PFC); (b) deficits in episodic memory performance among older adults originate from impairments in both strategic and associative components, reflecting senescent changes in the PFC and the medio-temporal lobes (MTL). Initial behavioral and neural evidence is consistent with both hypotheses. The two-component framework highlights the specificities of episodic memory in different age periods, helps to identify and dissociate its components, and contributes to understanding the interplay among maturation, learning, and senescence. [Copyright &y& Elsevier]

It has been suggested that volunteering leads to increases in well-being, particularly in older and retiring adults, and that volunteering could be used as a public health intervention to increase well-being. However, the causal relationship has been questioned. We investigated the association between voluntary work and life satisfaction in a bivariate dual-change score model, using 4 years of longitudinal data from 1,123 participants from the Health, Aging and Retirement Transitions in Sweden (HEARTS) study. Both the frequency of volunteering and the level of life satisfaction increased across the retirement transition. However, baseline life satisfaction and volunteering were only marginally associated. Further, the coupling parameters suggest that higher levels of volunteering were followed by decreases in life satisfaction and that higher levels of life satisfaction were followed by increases in volunteering. These findings suggest that increasing levels of volunteering might not be a fruitful strategy for improving life satisfaction for all older adults-if people engage too much in voluntary work, it might even be detrimental for their life satisfaction. More research is needed to better understand when and for whom increased levels of volunteering might have positive effects on life satisfaction. (PsycInfo Database Record (c) 2021 APA, all rights reserved). [ABSTRACT FROM AUTHOR]

Evidence from neuroimaging studies suggests a critical role of hippocampus and inferior frontal gyrus (IFG) in associative relative to item encoding. Here, we investigated similarities and differences in functional brain correlates for associative and item memory as a function of encoding instruction. Participants received either incidental (animacy judgments) or intentional encoding instructions while fMRI was employed during the encoding of associations and items. In a subsequent recognition task, memory performance of participants receiving intentional encoding instructions was higher compared with those receiving incidental encoding instructions. Furthermore, participants remembered more items than associations, regardless of encoding instruction. Greater brain activation in the left anterior hippocampus was observed for intentionally compared with incidentally encoded associations, although activity in this region was not modulated by the type of instruction for encoded items. Furthermore, greater activity in the left anterior hippocampus and left IFG was observed during intentional associative compared with item encoding. The same regions were related to subsequent memory of intentionally encoded associations and were thus task relevant. Similarly, connectivity of the anterior hippocampus to the right superior temporal lobe and IFG was uniquely linked to subsequent memory of intentionally encoded associations. Our study demonstrates the differential involvement of anterior hippocampus in intentional relative to incidental associative encoding. This finding likely reflects that the intent to remember triggers a specific binding process accomplished by this region. [ABSTRACT FROM AUTHOR]

Previous research shows that associative memory declines more than itemmemory in aging. Although the underlyingmechanisms of this selective impairment remain poorly understood, animal and human data suggest that dopaminergic modulation may be particularly relevant for associative binding. We investigated the influence of dopamine (DA) receptor genes on item and associative memory in a population-based sample of older adults (n = 525, aged 60 years), assessed with a face-scene item associative memory task. The effects of single-nucleotide polymorphisms of DA D1 (DRD1; rs4532), D2 (DRD2/ANKK1/Taq1A; rs1800497), and D3 (DRD3/Ser9Gly; rs6280) receptor genes were examined and combined into a single genetic score. Individuals carrying more beneficial alleles, presumably associatedwith higher DA receptor efficacy (DRD1 C allele; DRD2 A2 allele; DRD3 T allele), performed better on associativememory than persons with less beneficial genotypes. There were no effects of these genes on item memory or other cognitive measures, such as working memory, executive functioning, fluency, and perceptual speed, indicating a selective association between DA genes and associative memory. By contrast, genetic risk for Alzheimer disease (AD) was associated with worse item and associative memory, indicating adverse effects of APOE ε4 and a genetic risk score for AD (PICALM, BIN1, CLU) on episodic memory in general. Taken together, our results suggest that DA may be particularly important for associative memory, whereas AD-related genetic variations may influence overall episodic memory in older adults without dementia. [ABSTRACT FROM AUTHOR]

Experience can affect human gray matter volume. The behavioral correlates of individual differences in such brain changes are not well understood. In a group of Swedish individuals studying Italian as a foreign language, we investigated associations among time spent studying, acquired vocabulary, baseline performance on memory tasks, and gray matter changes. As a way of studying episodic memory training, the language learning focused on acquiring foreign vocabulary and lasted for 10 weeks. T 1 -weighted structural magnetic resonance imaging and cognitive testing were performed before and after the studies. Learning behavior was monitored via participants' use of a smartphone application dedicated to the study of vocabulary. A whole-brain analysis showed larger changes in gray matter structure of the right hippocampus in the experimental group (N = 33) compared to an active control group (N = 23). A first path analyses revealed that time spent studying rather than acquired knowledge significantly predicted change in gray matter structure. However, this association was not significant when adding performance on baseline memory measures into the model, instead only the participants' performance on a short-term memory task with highly similar distractors predicted the change. This measure may tap similar individual difference factors as those involved in gray matter plasticity of the hippocampus. [ABSTRACT FROM AUTHOR]

Associative memory involves binding two or more items into a coherent memory episode. Relative to memory for single items, associative memory declines greatly in aging. However, older individuals vary substantially in their ability to memorize associative information. Although functional studies link associative memory to the medial temporal lobe (MTL) and prefrontal cortex (PFC), little is known about how volumetric differences in MTL and PFC might contribute to individual differences in associative memory. We investigated regional gray-matter volumes related to individual differences in associative memory in a sample of healthy older adults (n = 54; age = 60 years). To differentiate item from associative memory, participants intentionally learned face–scene picture pairs before performing a recognition task that included single faces, scenes, and face–scene pairs. Gray-matter volumes were analyzed using voxel-based morphometry region-of-interest (ROI) analyses. To examine volumetric differences specifically for associative memory, item memory was controlled for in the analyses. Behavioral results revealed large variability in associative memory that mainly originated from differences in false-alarm rates. Moreover, associative memory was independent of individuals' ability to remember single items. Older adults with better associative memory showed larger gray-matter volumes primarily in regions of the left and right lateral PFC. These findings provide evidence for the importance of PFC in intentional learning of associations, likely because of its involvement in organizational and strategic processes that distinguish older adults with good from those with poor associative memory. [ABSTRACT FROM AUTHOR]

Prospective memory performance follows an inverted U-shaped function across the lifespan. Findings on the relative contribution of purely prospective memory and retrospective memory processes within prospective memory to this trajectory are scarce and inconclusive. We analyzed age-related differences in prospective memory performance across the lifespan in a cross-sectional design including six age groups (N= 99, 7–83 years) and investigated possible mechanisms by experimentally disentangling the relative contributions of retrospective memory and purely prospective memory processes. Results confirmed the inverted U-shaped function of prospective memory performance across the lifespan. A significant interaction between process type and age group was observed indicating differential relative contributions of retrospective memory and purely prospective memory processes on the development of prospective memory performance. Our results showed that mainly the pure prospective memory processes within prospective memory lead to lower prospective memory performance in young children and old adults. Moreover, the relative contributions of the retrospective memory and purely prospective memory processes are not uniform at both ends of the lifespan, i.e., in later adulthood the purely prospective memory processes seem to determine performance to an even greater extent than in childhood. Nevertheless, age effects were also observed in the retrospective component which thus contributed to the prospective memory performance differences between the age groups. [ABSTRACT FROM AUTHOR]

Abstract: In an fMRI study, 20 younger and 20 healthy older adults were scanned while performing a spatial working-memory task under two levels of load. On a separate occasion, the same subjects underwent PET measurements using the radioligand [11C] SCH23390 to determine dopamine D1 receptor binding potential (BP) in caudate nucleus and dorsolateral prefrontal cortex (DLPFC). The fMRI study revealed a significant load modulation of brain activity (higher load>lower load) in frontal and parietal regions for younger, but not older, adults. The PET measurements showed marked age-related reductions of D1 BP in caudate and DLPFC. Statistical control of caudate and DLPFC D1 binding eliminated the age-related reduction in load-dependent BOLD signal in left frontal cortex, and attenuated greatly the reduction in right frontal and left parietal cortex. These findings suggest that age-related alterations in dopaminergic neurotransmission may contribute to underrecruitment of task-relevant brain regions during working-memory performance in old age. [Copyright &y& Elsevier]

Background: Previous correlational studies have indirectly linked dysfunctional dopaminergic neurotransmission to age-related cognitive deficits and associated reductions in task-induced functional brain activity. Methods: We used an experimental-pharmacological functional magnetic resonance imaging (fMRI) approach to more directly examine the role of dopamine in neurocognitive aging. Twenty younger and 20 healthy older adults were included. During fMRI scanning, a spatial working memory (SWM) task was administered under two conditions, varying in cognitive load. Positron emission tomography measurements with the D1 receptor antagonist [11C]SCH23390 confirmed that a given experimental dose of unlabeled solution occupied 50% of D1 receptors in younger adults. Results: An age-related reduction in SWM performance was observed, and fMRI data revealed that, relative to younger adults under placebo conditions, elderly persons under-recruited load-sensitive fronto-parietal regions during SWM. Critically, in younger adults, the D1 antagonist resulted in a similar reduction in SWM performance and fMRI response. Conclusions: These results suggest that depletion of dopamine, whether ontogenetically or pharmacologically, results in decreased SWM performance as well as reduced load-dependent modulation of the blood oxygen level dependent signal in fronto-parietal regions, possibly by decreasing the signal-to-noise ratio in relevant neural networks. [Copyright &y& Elsevier]

Abstract: There is strong evidence that dopamine (DA) is implicated in higher-order cognitive functioning, but it remains controversial whether D1 receptor binding can be modified by cognitive activity. We examined striatal D1 binding potential (BP) in 20 younger (22–30 years) and 20 older (65–75 years) persons who underwent two [11C] SCH 23390 PET measurements, one while resting and one while performing a cognitive task taxing inhibitory functioning. The younger persons showed significant task-related BP reductions in sensorimotor, limbic, and associative striatum during cognitive activity compared to rest. Older persons showed no reliable BP reductions in any striatal subregion. These findings demonstrate that D1 receptor binding can be modified by cognitive activity in younger persons, but also provide novel evidence for the notion that human aging is associated not only with lower DA receptor density but also with altered modifiability of the DA system. [Copyright &y& Elsevier]

Functional magnetic resonance imaging (MRI) studies have demonstrated a critical role of hippocampus and inferior frontal gyrus (IFG) in associative memory. Similarly, evidence from structural MRI studies suggests a relationship between gray-matter volume in these regions and associative memory. However, how brain volume and activity relate to each other during associative-memory formation remains unclear. Here, we used joint independent component analysis (jICA) to examine how gray-matter volume and brain activity would be associated during associative encoding, especially in medial-temporal lobe (MTL) and IFG. T1-weighted images were collected from 27 young adults, and functional MRI was employed during intentional encoding of object pairs. A subsequent recognition task tested participants' memory performance. Unimodal analyses using voxel-based morphometry revealed that participants with better associative memory showed larger gray-matter volume in left anterior hippocampus. Results from the jICA revealed one component that comprised a covariance pattern between gray-matter volume in anterior and posterior MTL and encoding-related activity in IFG. Our findings suggest that gray matter within the MTL modulates distally distinct parts of the associative encoding circuit, and extend previous studies that demonstrated MTL-IFG functional connectivity during associative memory tasks. • Younger adults with better associative memory show larger gray-matter volume in left anterior hippocampus. • Gray-matter volume in medial temporal lobes covaries with encoding-related activity in inferior frontal gyrus. • The association between gray-matter volume and encoding-related activity did not predict associative memory performance. [ABSTRACT FROM AUTHOR]

Background: To study how event-related brain potentials (ERPs) and underlying cortical mechanisms of selective attention change from childhood to old age, we investigated lifespan age differences in ERPs during an auditory oddball task in four age groups including 24 younger children (9-10 years), 28 older children (11-12 years), 31 younger adults (18-25), and 28 older adults (63-74 years). In the Unattend condition, participants were asked to simply listen to the tones. In the Attend condition, participants were asked to count the deviant stimuli. Five primary ERP components (N1, P2, N2, P3 and N3) were extracted for deviant stimuli under Attend conditions for lifespan comparison. Furthermore, Mismatch Negativity (MMN) and Late Discriminative Negativity (LDN) were computed as difference waves between deviant and standard tones, whereas Early and Late Processing Negativity (EPN and LPN) were calculated as difference waves between tones processed under Attend and Unattend conditions. These four secondary ERP-derived measures were taken as indicators for change detection (MMN and LDN) and selective attention (EPN and LPN), respectively. To examine lifespan age differences, the derived difference-wave components for attended (MMN and LDN) and deviant (EPN and LPN) stimuli were specifically compared across the four age groups.Results: Both primary and secondary ERP components showed age-related differences in peak amplitude, peak latency, and topological distribution. The P2 amplitude was higher in adults compared to children, whereas N2 showed the opposite effect. P3 peak amplitude was higher in older children and younger adults than in older adults. The amplitudes of N3, LDN, and LPN were higher in older children compared with both of the adult groups. In addition, both P3 and N3 peak latencies were significantly longer in older than in younger adults. Interestingly, in the young adult sample P3 peak amplitude correlated positively and P3 peak latency correlated negatively with performance in the Identical Picture test, a marker measure of fluid intelligence.Conclusion: The present findings suggest that patterns of event-related brain potentials are highly malleable within individuals and undergo profound reorganization from childhood to adulthood and old age. [ABSTRACT FROM AUTHOR]