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Abstract: The human hippocampus is difficult to image given its small size, location, shape, and complex internal architecture. Structural magnetic resonance imaging (MRI) has shown that typical age-related hippocampal volume changes vary along its anterior–posterior axis. Diffusion tensor imaging (DTI) provides complementary microstructural metrics, but there are few hippocampus DTI studies investigating typical age-related changes and all are limited by low spatial resolution. Structural MRI has also demonstrated smaller hippocampal volumes in individuals with prenatal alcohol exposure (PAE), which animal models suggest may result from microstructural changes due to cell loss and altered myelination; however, there are no PAE hippocampus DTI studies. Moreover, there are complex intra-hippocampal pathways with crossing fibers that DTI cannot resolve, hence there are few in vivo hippocampus DTI tractography studies and a more sophisticated approach is necessary and would be valuable for examining neurological/psychiatric disorders. Constrained spherical deconvolution (CSD) can disentangle complex fibers, however the only hippocampal CSD study used a low b value and low spatial resolution. Chapter 4 uses high spatial resolution 1 mm isotropic DTI of 153 healthy volunteers aged 5–74 years to investigate hippocampus diffusion and volume trajectories (whole-structure/head/body/tail) and memory correlations. Manually traced (on mean diffusion-weighted images, DWI) hippocampal volumes demonstrated age-related changes that varied across the head/body/tail. Fractional anisotropy (FA) and mean/axial/radial diffusivities (MD/AD/RD) yielded peaks or minima, respectively, at ~30–35 years across the hippocampus. Memory and FA and/or volume correlations were significant in younger volunteers (5–17 years), but not 18–49 or 50–74 year-olds. MD significantly correlated with memory in 18–49 year-olds, but not at other ages. Chapter 4 demonstrated regionally-specific age effects and cognitive correlations along the hippocampus anterior–posterior axis from 5-74 years. These findings form the basis of comparison to numerous neurological or psychiatric disorders. Chapter 5 comprises the first application of hippocampus DTI in PAE. Using the 1 mm isotropic DTI from Chapter 4, T1-weighted images, and cognitive testing, 36 healthy controls (8-24 years) and 19 participants with PAE (8-23 years) were studied. Whole-hippocampus volumes were 18% smaller in PAE than in controls on manually traced DTI, but automated T1-weighted image segmentations did not show group differences. Manual subregion DTI segmentation revealed reduced body/tail but not head volumes. There were no hippocampal diffusion metric group differences. Age and volume correlations were not significant in either group, whereas negative correlations between age and whole-hippocampus MD/AD/RD, and head/body (but not tail) MD/AD/RD were significant in both groups. In controls, seven positive linear correlations were found between hippocampal volume and episodic and working memory (left) and working memory and processing speed (right). In PAE, left tail MD positively correlated with executive functioning, and right head MD negatively correlated with episodic memory. Chapter 5 demonstrated hippocampal volume reductions and altered relationships with memory that suggest disrupted hippocampal development in PAE. Chapter 6 uses a multi-shell (64 b500s; 64 b2000s) version of the 1 mm isotropic diffusion protocol in Chapters 4/5. This qualitative pilot study included: 40 cross-sectional (scanned once) volunteers aged 5-90 years to demonstrate the feasibility of CSD tractography in comparison to DTI tractography across the lifespan, and six longitudinal (scanned twice) volunteers aged 23-40 years to demonstrate replicability. DTI ellipsoid maps and streamlines and CSD fiber orientation distribution function maps and streamlines demonstrated consistent anatomically-plausible fiber orientation patterns corresponding to polysynaptic and direct hippocampal pathways from 5-90 years and across the longitudinal data. CSD provided additional information in the form of anatomically-plausible crossing fibers that DTI could not resolve due to model limitations; the greatest portion of crossing fibers was in the hippocampal head. High spatial resolution diffusion data enables both DTI and CSD-based intrahippocampal tractography to provide anatomically-plausible results, but only CSD can resolve crossing fiber regions. Chapter 6 suggests that high spatial resolution diffusion tractography with DTI or CSD could be applied to study neurological and psychiatric disorders to identify potentially missing streamlines or differences in quantitative tract-based metrics that may relate to memory and other cognitive deficits. Altogether, this thesis demonstrates the applicability of clinically-relevant 1 mm isotropic hippocampus diffusion MRI protocols. These 3T MRI acquisitions allowed for novel studies of the hippocampus in humans across the typical life span (Chapters 4/6) and with PAE (Chapter 5).

Perceptual decision-making, evaluating the sensory world in order to choose an action, is often done in conditions of uncertainty. People can implicitly learn from past experiences in order to help the decision-making process but the conditions in which this happens and how metacognition impacts this is unknown. Furthermore, how this ability to implicitly learn priors changes with healthy aging has not been studied. In these three studies, participants performed a perceptual decision-making task in which different colored stimuli were associated with different prior biases (e.g., 75% of the red trials go leftward). In Study 1, we examined the differences between learning priors implicitly through experience versus explicit instruction and how that affects performance and metacognition with two computational models, Linear Ballistic Accumulator Model (LBA) and a Hierarchical Bayesian Estimation of metacognition (H-Meta- d’). Participants were able to learn priors implicitly and used them to guide decision-making. Bias primarily influenced decisions with the least sensory information, but not for stimuli with more robust information. Those who were instructed of the priors were more confident for prior- consistent (vs. inconsistent) stimuli while this was not seen in participants who experienced the priors implicitly. However, there were no differences in metacognitive efficiency between the two instruction groups. Our results suggest that implicitly learned priors can influence decision-making when sensory information is unreliable, but do not contribute when sensory information is more robust. In Study 2, older and younger adults performed the same decision-making task with prior instruction manipulation but with different prior conditions. Instead of opposite-oriented priors, one prior was biased towards a side while the other prior was equally likely to go left or right. When participants were instructed of priors, younger adults were faster and more accurate compared to older adults. Younger adults were more confident for Positive prior (biased) trials while older adults’ confidence was unaffected by prior condition. In contrast, in the implicit “experience” group, younger and older adults largely matched on speed and accuracy, but younger adults were more confident than older adults overall. LBA parameter estimates largely align with past research that suggests that older adults have a slower information processing rate, greater response caution and require more evidence before making a decision (Garton et al., 2019). In Study 3, I present preliminary results of functional magnetic resonance imaging to examine the neural correlates of implicit learning and decision-making. Activation in the putamen and thalamus was observed during prior-consistent Equal prior trials with little sensory information. Motor and visual areas, as well as frontal gyri were primarily activated for the Positive Prior trials that were prior-consistent. Findings from these studies may augment understanding of the decision-making mechanisms in healthy aging as well as in clinical patient populations and may provide insight into novel therapies or rehabilitation.

The main goal of this research is to investigate the cross-cultural differences in perceptions of the importance of the microlevel (e.g., exercising) and macrolevel (e.g., education) factors of healthy aging among adults in the United States and Saudi Arabia. The participants include Saudi adult men and women ages 18 years and older who are living in the U.S. (n = 23) and U.S. adults (n = 45). Respondents completed an online survey that included questions about their perceptions of the importance of the main factors of healthy aging. The findings of this study suggest that drinking alcohol, engaging in creative arts, engaging in cognitively stimulating activities and receiving care from others reflect cross-cultural differences in perceptions of healthy aging between Saudi adults and the U.S. adults. These findings help in understanding the perceptions of the importance of the underlying factors of healthy aging in the United Sates and Saudi Arabia.

Objective: This thesis aims to identify novel relationships between modifiable physical and health variables, Alzheimer’s disease (AD) biomarkers, and cognitive function in a cohort of older adults with mild cognitive impairment (MCI). Methods: Metrics of cardiometabolic risk (e.g., body mass index), stress (e.g., cortisol), inflammation (e.g., c-reactive protein), neurotrophic/growth factors (e.g., brain-derived neurotrophic factor), and AD (e.g., plasma tau) were assessed in 154 MCI participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) at baseline (mean age = 74.1; sd =7.5; mean education = 16.0; sd = 2.9). Of these 154 participants, 126 had 2-year follow-up data available for analyses (mean age = 74.0; sd = 7.6; mean education = 16.0; sd = 2.9). Participants also completed a comprehensive neuropsychological battery. Individual test scores and composite scores of memory and executive function published by ADNI were assessed. Partial least squares correlation (PLSC), an unbiased and flexible multivariate technique, was employed to examine cross-sectional associations among these physiological variables and cognition. Partial least squares regression (PLSR), a multivariate technique that defines optimal combinations of variables that best predict an outcome, was used to identify which, if any, of these physiological variables are important in predicting memory or executive function at 2-year follow-up.Results: The PLSC analysis revealed a latent variable describing a unique combination of AD biomarkers, neurotrophic/growth factors, education, and stress that were significantly associated with specific domains of cognitive function, including episodic memory, executive function, processing speed, and language, representing 45.2% of the covariance in the data. Age, BMI, and tests of basic attention and premorbid IQ were not significant. The PLSR analyses revealed that baseline metrics of cardiometabolic function, inflammation, and AD biomarkers were important in predicting memory and executive function performance at 2-year follow-up. Baseline education was important in predicting memory but not executive function performance at 2-year follow-up. Our two best models predicted 65.1% and 63.7% of the variance in memory and executive function respectively at 2-year follow-up.Conclusion: Our data-driven analysis highlights the significant cross-sectional relationships between metrics associated with AD-pathology, neuroprotection, and neuroplasticity primarily with tasks requiring higher order cognitive abilities (episodic memory, executive function, verbal fluency), rather than cognitive tasks that do not require mental manipulation (premorbid IQ and basic attention). Baseline metrics of cardiometabolic function, inflammation, and AD pathology were statistically important in predicting future memory and executive function performance at 2-year follow-up, suggesting that variables associated with neuroprotection and neuroplasticity (such as brain-derived neurotrophic factor and platelet-derived growth factor) may hold relatively less importance in predicting future cognition.

In the United States, the older population in consistently growing, with 17.7% of adults over the age of 65 in South Carolina alone. As aging populations grow, research must examine factors linked to longevity and extended quality of life, as well as facts in both middle and later life that are associated with higher levels of successful aging (SA). This study examined the relationship between the Community Health Activities Model Program (CHAMPS) or the Health-Promoting Lifestyle Profile (HPLP II) and fourteen selected markers of health and SA. Anthropometric data (including bodyweight, height, blood pressure, grip strength, body mass index, body composition, waist circumference, hip circumference, SPO2, mid-arm muscle circumference and pulse) was collected from participants over the age of 45 at three time points over a 12-week period. Statistical analysis showed that higher levels of activity in older adults were associated with a number of improved health markers including increased lean body mass and decreased waist circumference. This supported the idea that individuals living in an active living community who engage in the more developed built environment and resources for physical activity have a number of indicators associated with successful aging. The physiological indicators measured, and the questionnaire responses provided suggest that access to a safe, available built environment that promotes physical activity could be of benefit to all individuals as they age to promote the attainment of successful aging.

INTRODUCTION: Research studies on the general working population (aged 18-64) have found associations between access to paid sick leave (PSL) and increased uptake of preventive health screenings, but few such studies have been done on the fastest growing segment of American workers: those aged 55 and older, and rarely treating paid sick leave as anything but a “yes/no” exposure. AIM: The aims of this work are to determine the associations between access to PSL and preventive health behaviors (blood cholesterol test, flu shot, seeing the dentist) and depression among a nationally representative sample of workers over the age of 51. METHODS: Using cross-sectional data from the 2014 Health and Retirement Study, we examined associations between PSL and respective outcomes while exploring and comparing techniques to adjust for confounding. PSL was considered as either dichotomous (yes/no) or trichotomous (zero days, 1-9 days, 10+ days) exposure. Two confounder pools were identified, on the basis of previous literature and bivariate associations within this study: covariates that may predict PSL availability, and covariates that may confound the relationship between PSL availability and a given study outcome (e.g. social support as a covariate that would confound the association between PSL availability and depression). Propensity score models were developed and different adjustments explored in multivariable logistic regression models. For each study outcome, a range of models to address confounding were run, including 1) traditional multivariable logistic models adjusting for both covariates that predict PSL availability and covariates specific to the paid sick leave and specific study outcome, and 2) multivariable logistic models adjusting for only the propensity score as a continuous covariate and additional select covariates likely to confound the paid sick leave and specific study outcome. RESULTS: After adjusting for confounders via models that used traditional multivariable logistic regression and multivariable logistic regression incorporating the propensity score as a continuous covariate and health insurance as an additional covariate, the association between PSL availability (1+ days versus zero days) and receiving a cholesterol test was characterized by estimated odds ratios (OR) of 1.39 (95% CI: 0.99, 2.94) and 1.37 (95% CI: 0.98, 1.92), respectively. After adjusting for confounders via traditional multivariable logistic regression and multivariable logistic regression adjusting for the propensity score and dental insurance, participants with 1+ days PSL had 1.3 times the odds of reporting a dental visit (95% CI: 0.95, 1.79), and 1.22 times the odds of reporting a dental visit (0.90, 1.65), respectively, compared to those who had zero days. Although not statistically significant, trends in the measures of association between PSL as a trichotomous exposure and cholesterol testing and dental visits indicated that participants with higher levels of PSL had higher odds of the outcome than individuals in the next lower category of paid sick leave availability (e.g. using traditional multivariable logistic regression, participants who had 1-9 days PSL had 1.2 times the odds of reporting a cholesterol test compared to those who had zero (95% CI: 0.81, 1.78); by that same model, participants who had 10+ days PSL had 1.6 times the odds of reporting a cholesterol test compared to those who had zero (95% CI: 1.08, 2.36)). Similarly, examination of the relationship between PSL and depression indicated an inverse relationship, though this also was not statistically significant. No associations were found between paid sick leave availability and receiving a flu shot. DISCUSSION: This study provides preliminary evidence that paid sick leave access might be associated with increased cholesterol tests and dental visits among older workers. These findings may have implications for employment policy as well as public health practice. However, more research is needed to examine how access to paid sick leave affects these health outcomes over time before stronger causal statements can be made.

Introduction: The number of older adults with a serious mental illness (SMI) is predicted to more than double to 15 million by the year 2030. Older adults with SMI tend to have multiple medical problems in addition to serious psychiatric symptoms. Although the concept of healthy aging in SMI is gaining further attention, it has not historically been a common framework for mental illness treatment, rehabilitation, or recovery. Healthy aging includes the promotion of interconnected aspects of physical, emotional, and psychological wellbeing. The burgeoning field of inquiry about the effects of exergames on physical health and psychological wellbeing in older adults has found that exergames are safe, effective, enjoyable, and may improve depressive symptoms. Methods: We conducted qualitative interviews with 15 older adults with SMI who participated in a 10-week group exergame program. Data were collected and analyzed using grounded theory methodology within a symbolic interactionist framework. Results: Three important and interrelated concepts emerged from the data: Competence, Social Connectedness, and Energy. Play and playfulness became the vehicle for interacting social processes to take place. In the context of play, the participants experienced themselves in relationship to one another, gave and received empathy and positive social contact, engaged in social attunement, and became motivated to take risks and to face cognitive and physical challenges. In social environments where higher playfulness was cultivated, participants were more willing to engage in competition and described a sense of subjective wellbeing. Play and playfulness is strongly associated with increased social connectedness, which in turn supports intrinsic motivation, self-determination, and fulfills certain innate psychological needs that support wellness, growth, and recovery. Conclusion: Social disconnectedness and perceived isolation among older adults with SMI is complex and involves factors including organic psychopathology, physical effects of medications and/or other substances, medical co-morbidity, disability, and social stigma. Group play exergames for older adults with SMI may have the potential to promote recovery and healthy aging by increasing social integration, improving self-efficacy, and promoting physical health through exercise.

Increasing rates of overweight, obesity, and related cardiovascular diseases among older adults in the United States present unique public health challenges. Cross-cultural research has shown marked variation in health across the world’s elder populations because aging is a biological process rooted in sociocultural context. The sociocultural environment contributes to complex negotiations of food and physical activity patterns for older adults. It is well established in the literature that urban residents report low levels of physical activity and have easy access to fast food outlets, which tend to be concentrated in lower-income neighborhoods. I utilize a biocultural framework, integrating nutritional anthropology with healthy aging perspectives to recognize the role of the social determinants of health throughout the lifespan. This anthropological study integrates qualitative and quantitative methods to answer the following research question: What is the relationship between the sociocultural factors that shape diet, physical activity, and nutritional status among Alaskan elders in Anchorage? The results indicate that diet and physical activity practices in this sample do not meet national recommendations and that diet differs adversely from national reference samples. Statistical analyses indicate that the media and friends positively influenced older adults to increase their energy expenditure. Family influences increased fruit consumption, while participation in cultural and social events increased intake of fats and sweets. Cultural identity was an important factor for Alaska Native participants’ dietary selections. Social supports increased access to healthy foods and safe physical activities. This research suggests that trying to reach older adults with diverse needs through a variety of channels, including the media, social networks, and social events, can help alleviate some of the barriers to healthy diet and exercise patterns. These data indicate a need for culturally-responsive programs that maintain relationships with family members and make connections between elders with similar healthy aging goals in order to improve diet and physical activity practices.

The purpose of this study was to examine older adults’ wellness and resilience, identify whether these constructs were related to perceptions about older adulthood, and juxtapose a wellness and resilience paradigm of aging against models that focus on the biomedical aspects of aging. The study used descriptive and multivariate analyses to examine data collected from a sample of individuals ages 56 to 97 who were residing in age-restricted, independent living housing communities across Franklin County (N = 200). The analyses revealed numerous statistically significant relationships among the study variables. Group differences revealed that older members of the sample had higher levels of wellness (p = .01) and resilience (p = .001), and those who indicated self-rated depression symptoms had lower levels of wellness, resilience, and positive age perception, along with higher levels of internalized ageism (p < .01). Regression analyses revealed that resilience (p < .01) and physical wellness (diet and exercise) (p < .01) were predictors of total age perception; resilience (p = .01) and total wellness (p < .001) were significant predictors of positive self-perceptions of aging; and physical wellness (diet and exercise) (p < .01) and age (p < .01) were significant predictors of internalized ageism. Additional analysis revealed that the effect for age was conditional upon resilience level, in which individuals 75 years and older with low levels of resilience were far more likely to experience internalized ageism. Additionally, a discriminatory analysis revealed that the ability to cope and resilience had the strongest association with whether or not individuals rated themselves as suffering from depression symptoms. Exploratory analyses also revealed that wellness explained a far greater share of variance in happiness, life satisfaction, and self-rated physical health than whether individuals met the traditional biomedical criteria for successful aging. The results of this study provide empirical support for the relationship between wellness, resilience, and age perception, suggesting that holistic, strengths-oriented models of aging may be needed to complement biomedical, pathogenic conceptualizations of the aging process.

The dissertation research described herein examined several facets of pattern separation (conceptualized as an encoding process whereby two very similar stimuli are stored as discrete representations). Previous research has conceptualized pattern separation as a discrete, high threshold process and has relied upon performance measures that are derived from that theory. More recently, it has been suggested that pattern separation may be better fit by a continuous, signal-detection-based model. Should that be the case, it would mean that previous work examining pattern separation in aging and dementia has relied upon potentially misleading dependent measures. The current project had three goals: 1) to determine the most appropriate cognitive modeling for pattern separation, 2) to examine whether or not pattern separation is selectively impaired in aging and dementia populations, and 3) to compare biomarkers of preclinical impairment with performance on behavioral recognition memory and pattern separation tasks. In Chapter 1, ROC and d’ analyses showed that pattern separation is indeed best conceptualized as a continuous signal detection process. In Chapters 2 and 3, we took the framework for pattern separation identified in Chapter 1 and applied it to a population consisting of young adults, older adults, individuals with amnestic mild cognitive impairment (aMCI), and Alzheimer’s disease. The general approach was to first try to equate performance across groups on a recognition memory task and then compare group performance on the pattern separation task. Taken together, Chapters 2 and 3 provided evidence that pattern separation is selectively impaired in aMCI and possibly in healthy older adults as well, and this deficit is not explained by a recognition deficit alone. In Chapter 4 we measured the relationship between behavioral performance measures (on both the recognition memory tasks and pattern separation tasks) and cerebrospinal fluid biomarkers (Aβ42 and tau levels) in healthy aging participants. We found a significant positive correlation between performance on both the recognition memory task and the pattern separation task, but only for pictures of everyday objects. Thus, these biomarkers are predictive of general memory performance for objects but do not selectively predict pattern separation performance.

The orofacial area stands apart from other body systems in that it possesses a unique performance anatomy whereby oral musculature inserts directly into the underlying cutaneous skin, allowing for the generation of complex three-dimensional deformations of the orofacial system. This anatomical substrate provides for the tight temporal synchrony between self-generated cutaneous somatosensation and oromotor control during functional behaviors in this region and provides the necessary feedback needed to learn and maintain skilled orofacial behaviors. The Directions into Velocity of Articulators (DIVA) model highlights the importance of the bidirectional relationship between sensation and production in the orofacial region in children learning speech. This relationship has not been as well-established in the adult orofacial system. The purpose of this observational study was to begin assessing the perception-action relationship in healthy adults and to describe how this relationship may be altered as a function of healthy aging. This study was designed to determine the correspondence between orofacial cutaneous perception using vibrotactile detection thresholds (VDT) and low-level static and dynamic force control tasks in three representative age cohorts. Correlational relationships among measures of somatosensory capacity and low-level skilled orofacial force control were determined for 60 adults (19-84 years). Significant correlational relationships were identified using non-parametric Spearman’s correlations with an alpha at 0.1 between the 5 Hz test probe and several 0.5 N low-level force control assessments in the static and slow ramp-and-hold condition. These findings indicate that as vibrotactile detection thresholds increase (labial sensation decreases), ability to maintain a low-level force endpoint decreases. Group data was analyzed using non-parametric Kruskal-Wallis tests and identified significant differences between the 5 Hz test frequency probe and various 0.5 N skilled force assessments for group variables such as age, pure tone hearing assessments, sex, speech usage and smoking history. Future studies will begin the processing of modeling this complex multivariate relationship in healthy individuals before moving to a disordered population.

This study investigated the lifespan influences of task type and working memory on the syntactic complexity of narrative discourse production. Participants included 180 healthy adults across three age cohorts: 20-29 years (Young Group), 60-69 years (Older Group) and 75-89 years (Elderly Group). Participants completed standardized working memory measures and four discourse tasks (single/sequential picture description, storytelling and personal recount). Syntactic complexity for each sample was measured via clausal density yielding a complexity index. For analysis, participants were placed into one of two groups based on working memory scores above (High Working Memory Group) or below (Low Working Memory Group) the mean. Significant differences in syntactic complexity between working memory groups were found for the single picture description and the storytelling; individuals in the high working memory group produced language with greater syntactic complexity. When the effects of cohort and working memory were investigated with a two-way ANOVA, working memory group was no longer significantly related to syntactic complexity. However, there was a significant relationship between cohort and syntactic complexity for the single picture description and storytelling tasks. Analyses indicate that the relationships between syntactic complexity, age, and working memory are dependent on task type.

Abstract: Although many policy frameworks, research definitions and programs on Healthy Aging are available in Canada and abroad, little is known about older adults’ perspectives on this topic. Given the steady increase of the numbers of older Canadians, as well as the diversity of their cultural background in Alberta, the present study introduces the healthy aging perspectives of eight older Francophones of French Canadian descent living in Edmonton, Alberta, using Interpretive Description as a qualitative methodology. Three central themes of healthy aging were identified from participants’ interview data: protecting health, maintaining dignity, and preserving identity to achieve healthy aging. Study findings were further re-interpreted in the light of available research and suggestions were made to inform current healthy aging practice interventions, research programs, and policies put in place to possibly enhance healthy aging for all Francophone and non-Francophone communities in and outside Edmonton, Alberta.

Healthy aging is defined as aging in the absence of chronic diseases that limit physical function and mobility. With the increasingly high prevalence of chronic diseases and their risk factors in the United States, it is important to better understand the contributors and predictors of health and longevity. Molecular markers of the epigenome provide one novel set of biomarkers to investigate the intersection of the effects of genetic variation and environmental variation in the initiation and progression of chronic disease. This dissertation focuses on (1) investigating associations between 26,428 DNA methylation markers and chronological age, (2) elucidating the environmental and genetic components of the variation of 26,428 DNA methylation markers, and, finally, (3) predicting aging with DNA methylation markers sites in an African-American population of sibships from the Jackson, MS field center of the Genetic Epidemiology Network of Arteriopathy (GENOA) study. We found that 27% of the genome-wide DNA methylation sites are significantly associated with age. The majority of DNA methylation sites (88%) have significant heritabilities, and there is evidence of an age-related genetic component to this heritability. Finally, when predicting aging, inflammatory biomarkers and DNA methylation markers, together, were found to explain 14% of the variation in aging. This dissertation illustrates that DNA methylation patterns measured in epidemiological studies may be able to provide new insights into the molecular processes underlying aging and chronic disease development.

This study investigated the accuracy of healthy aging adults‟ self-rating of communication style, as measured by quantifiable measures of discourse performance. Ninety cognitively healthy adults participated and comprised three age cohorts (20s, 40s, 60s). Participants completed discourse tasks that included recounting a vacation, telling a story, and describing a picture. Participants also self-rated their communication style, placing them in a talkative or reserved cohort. Communication style was measured by discourse performance variables of interest: length of output (TNW) and informativeness (%IU). When presented with an unconstrained task (recounting a vacation), talkative and reserved groups, regardless of age, produced a similar TNW and %IU. When considering age and self-rating, talkative 20, 40, and 60 year olds produced a similar TNW and %IU as reserved 20, 40, and 60 year olds. Overall, adults were found to be inaccurate, due to lack of significant differences between self-rating groups. Results indicated the need for further research on the relationship between age, discourse performance, and accuracy of self-rating of communication style of healthy aging adults.

The discourse of older healthy adults is commonly described as lengthy and off-topic and thought to be associated with a general cognitive decline that occurs in healthy aging. This study investigated the overall decline in attention associated with healthy aging and its relationship to instances of off-topic speech (OTS) in a constrained and unconstrained language production task. Ninety cognitively healthy adults participated and comprised three age cohorts (40 – 75+). Participants completed cognitive measures of attention and two discourse tasks that included recounting personal events and describing a procedure. Older adults exhibited poorer scores on measures of selective and shifting attention, and elderly adults produced more OTS as compared to middle-aged (40s) and older (60s) adults in the unconstrained task only. Poorer scores of shifting attention were significantly correlated with more OTS in the older adults (60s) only. Overall, a marked increase in variability of language production was observed with advancing age. Results indicated the need for further research on the relationships between age, attention, OTS, and task type in healthy aging to determine an underlying cause for increasing variability of language production with age.

The trends toward population ageing and urbanization highlight the important influence of urban environments to healthy ageing. The World Health Organization (2007) has identified green space as an important feature of age-friendly cities contributing to active ageing and well-being in later life. Emerging research concerned with the influence of contact with nature provides evidence of the significance of nature rich settings to health and well-being. This research explores the value and meaning of nature rich urban parks to older women, and the influence of park use on healthy ageing. Several methods were employed in this research. Older women from Hagley Park in Christchurch, New Zealand and Boulevard Lake in Thunder Bay, Canada participated in this research. The participants produced photographs to represent the value and meaning of the parks in their lives. These images were supplemented with written descriptions and anecdotes associated with their use of the parks. The photos and written descriptions were then used as a guide during individual interviews. Site surveys provided insight into the features and qualities of the parks. The findings of this research indicate that the parks are valued for their nature rich qualities, opportunities for social contact and healthy activity. A park value that appears to particularly resonate among older women involves the park as a venue for maintaining a connection with the past and supporting a sense of continuity. The nature rich quality of the parks has an overarching influence on the multiple, interrelated park meanings, although the influence of the park as an urban setting is also significant. The meaning of the parks is shaped by their urban location, the highly developed and managed quality of the park settings, the social and temporal dimensions of the parks, and the effect of culture and heritage. A conceptual framework of ‘green ageing’ is proposed to describe the influence of nature rich settings on opportunities for optimising social, physical and mental health in later life.

At the beginning of the last century, 1 in 25 Americans was age 65 or over. By 2050, however, 1 in 5 will be an older adult. Because older adults shoulder a disproportionate share of health problems, concerns have been raised about the impact that an expanding older population will have on American society. Research suggests, though, that good health in the later years is possible and that health promotion efforts may help avert some of the costs of a growing older population. Currently, little is known about the prevalence of healthy aging in the US. To help fill this void, Rowe and Kahn's notion of healthy aging, referred to as successful aging, was examined. Using 1998, 2000, 2002, and 2004 data from a nationally-representative study of older adults, the prevalence of successful aging was estimated for the older population as a whole and major subgroups of older adults. Additionally, trends over time in the prevalence of the phenomenon were examined to determine if the percentage of older adults aging successfully has changed in recent years. Guided by Rowe and Kahn's framework, successful aging was operationalized as having no difficulty with six activities of daily living, none of five chronic diseases, no more than one difficulty with seven measures of physical functioning, a median or higher score on tests of cognitive functioning, and being actively engaged. Analyses were restricted to the roughly 10,000 adults at each wave who were ages 65 and over. Results indicate that fewer than 10% of older adults were aging successfully in any wave. In adjusted analyses, those of lower SES, advanced age, and male gender were consistently found to have lower odds of aging successfully than their respective counterparts. In addition, for the most recent wave of data collection, those of non-White race/ethnicity had just half the odds of aging successfully as older White adults. Over the six-year period, the prevalence of successful aging declined by 19%, with differential trends by SES evident in 2004. The implications of these findings for the continued study and development of the concept of successful aging are discussed.