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Process Dissociation Analyses Of Memory Changes In Healthy Aging, Preclinical, And Very Mild Alzheimer Disease: Evidence For Isolated Recollection Deficits, Peter R. Millar

Arts & Sciences Electronic Theses and Dissertations

Recollection and familiarity are independent processes that contribute to memory performance. Recollection is dependent on attentional control, which breaks down in early-stage Alzheimer disease (AD), whereas familiarity is independent of attention. The present study examines the sensitivity of recollection estimates based on Jacoby’s (1991) process dissociation procedure to AD-related biomarkers in a large sample of well-characterized cognitively normal older adults (N = 519) and the extent to which recollection discriminates these individuals from individuals with very mild symptomatic AD (N = 64). Participants studied word pairs, e.g., “knee bone,” then completed a primed, explicit, cued fragment-completion memory task, e.g., “knee …

Examining Age Differences In Metamemory For Emotional Words, Samuel Ethan Flurry

Theses and Dissertations

Metamemory is “knowing about knowing” (Flavell, 1971) and is theorized as a cognitive process that monitors and controls the memory system (Flavell & Wellman, 1975; Nelson & Narens, 1990). The predominate finding in the metamemory and aging literature is that metamemory is unimpaired by aging, even when memory is impaired by aging (Eakin & Hertzog, 2006; 2012; Connor, Hertzog, & Dunlosky, 1997; Hertzog, Sinclair, & Dunlosky, 2010; Eakin, Hertzog, & Harris, 2014, but see Souchay, Moulin, Clarys, Taconnat, & Isingrini, 2007). However, a study examining metamemory for emotional words suggests older adults may show metamemory impairment when predicting memory for …

Role Of Selenium In Age-Related Degeneration: Selenotranscriptome Hierarchy And Characterization Of Selenoprotein H, Lei Cao

Theses and Dissertations

Selenium (Se) is an essential trace element exerting its biological functions mainly through selenoproteins. Our lab has recently shown a paradoxical role of dietary Se at nutritional levels of intake in the delay of age-related degeneration while reducing longevity in mice carrying humanized telomeres. The first aim of this dissertation was to evaluate the effects of long-term dietary Se deficiency, aging, and sex on selenotranscriptome hierarchy in tissues. Four unique patterns in selenotranscriptomic changes were summarized. First, the responses of selenotranscriptomes to dietary Se deprivation and aging were sexually dimorphic. Second, a few selenoproteins responded to dietary Se deficiency and …

Oocyte Quality: Molecular Constituents Altered In The Oocyte Due To Various Environmental Factors, Lindsay Cox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An estimated 1.6 million American couples struggle with infertility. Some causes for poor fertility can be clearly defined but in many instances, subfertility is unexplained. Poor oocyte quality is now considered to be a main contributing factor for many causes of infertility. Good oocyte quality is crucial for many processes including embryo development and maintaining pregnancy. There is a possibility that any alterations to the oocyte can have long lasting effects on embryo development and the health of the offspring. The oocyte is very sensitive to any perturbations to its surrounding environment. Transcripts for apoptosis inhibitors and epigenetic modifiers were …

Apoaequorin Differentially Modulates Fear Conditioning In Adult And Aged Rats, Vanessa Ehlers

Theses and Dissertations

Normal aging is associated with a number of changes in behavioral and cellular function, and is often linked to increased susceptibility to cognitive impairment. The hippocampus has been widely implicated in learning and memory, and many forms of learning that are hippocampus-dependent (e.g. trace fear conditioning) are impaired in aged animals. A proposed contributor to aging-related cognitive impairment is aging-related calcium (Ca2+) dysregulation. This dysregulation is thought to result from changes in specific Ca2+-regulatory mechanisms, including abnormal Ca2+ ion channel activity or expression, as well as reduced Ca2+-binding protein (CaBP) expression, which is associated with cognitive and synaptic impairment. Previous …

Extracellular Matrix Remodeling And The Inflammatory Response During Skeletal Muscle Regeneration In Sarcopenic Obese Mice, Lemuel Arthur Brown

Graduate Theses and Dissertations

AIM: Sarocpenic obesity is a national concern within the United States because this metabolic syndrome is tied with reduced mobility and quality of life. Both obesity and aging are associated with insulin-resistance, chronic low-grade inflammation and muscle weakness. Skeletal muscle regeneration is a process that involves the coordinated effort of myogenic regulatory factors (MRFs), inflammatory signaling, and extracellular matrix (ECM) remodeling for optimal regeneration. It has been demonstrated that obesity and aging have a reduction in muscle regeneration. It has not been examined if sarcopenic obesity will further reduce muscle mass and the regenerative process. The purpose of this study …

Neural Correlates Of The Development Of Cognitive Flexibility, Dina R. Dajani

Open Access Theses

One aspect of executive function, cognitive flexibility, is necessary for implementing the appropriate and efficient adaptation of cognitions in the face of changing environments. In a recently proposed framework, cognitive flexibility is thought to involve multiple component functions: stimulus-driven attention and two related executive functions, working memory and inhibition. These executive functions commonly recruit the frontal, cingulate, and parietal brain regions, but it is unclear whether cognitive flexibility and its component functions arise from specific connectivity profiles within this superordinate fronto-cingulo-parietal network. The objectives of this study were to 1) index behavioral changes in attention, working memory, inhibition and cognitive …

Does Age Influence Dynamic Stability And Muscular Power Following Neuromuscular Fatigue In Women?, Ben J. Hoffmann

Masters Theses

Older adults, especially older women, produce less muscular power than young adults, due primarily to slower maximal contractile velocity. These decrements may lead to increased fall risk in older women and can be exacerbated by fatigue. Recently, a 32 min walking task (32MWT) was shown to elicit fatigue in older women. The purpose of this study was to determine whether knee extensor (KE) maximal velocity is related to dynamic stability (margin of stability, MoS) in young and older women pre- and post-32MWT. METHODS: Nine young (Y; 24.3+1.1years, mean±SE) and 17 older (O; 71.1±1.1years) healthy women completed 2 testing sessions on …

Multi-Nuclear Magnetic Resonance Imaging Of Obstructive Lung Disease, Khadija Sheikh

Electronic Thesis and Dissertation Repository

Obstructive lung diseases such as chronic-obstructive-lung-disease (COPD), bronchiectasis, and asthma are characterized by airflow obstruction. They affect over six million Canadians costing the economy $12 billion/year. Despite decades of research, therapies that modify obstructive-lung-disease progression and control are lacking because patient diagnosis, monitoring, and response to therapy are currently made using airflow measurements that may conceal the independent contributions of underlying pathologies. One goal of obstructive-lung-disease research is to develop ways to identify patients with specific underlying pathological phenotypes to improve patient care and outcomes. Thoracic computed-tomography (CT) and magnetic-resonance-imaging (MRI) provide ways to regionally identify the underlying pathologies associated …

Intraindividual Variability As A Predictor Of Cognitive Decline In Elderly, Wendy S. Ramratan

Dissertations, Theses, and Capstone Projects

Mild cognitive impairment (MCI) is conceptualized as a transitional state between normal aging and fully developed clinical features of dementia. The literature on MCI is notable for varied measurement approaches and lack of stability in the diagnostic entity, with many individuals remaining stable or reverting to normal cognitive status. Researchers agree that multiple neuropsychological domains should be assessed to enhance the assessment and prediction of cognitive decline. In addition, within-person assessments capture trajectories of decline, which are better suited for understanding individual change than simple comparison to group norms. The current study investigated the ability of within-person change on novel …

Emotion Regulation In Relation To Cognitive Functioning In The Preclinical Stages Of Dementia, Erica P. Meltzer

Dissertations, Theses, and Capstone Projects

Emotion regulation (ER) is essential for effective functioning in daily life. Research suggests that ER improves in older adulthood despite concomitant declines in cognition and the presumed neural substrates of ER. The current understanding of ER in older adulthood, and particularly of the relationship between ER and cognition in older adulthood, is limited. This is likely because the construct of ER is challenging to operationalize and, therefore, difficult to study.

The current study investigates ER in relation to cognitive functioning, specifically executive functioning and memory, in individuals with varying degrees of cognitive difficulties (i.e., in the preclinical stages of dementia). …

Category Learning In Older Adulthood: Understanding And Reducing Age-Related Deficits, Rahel R. Rabi

Electronic Thesis and Dissertation Repository

Executive functions are important for learning rule-based (RB) categories, as well as non-rule-based (NRB) categories (e.g., categories learned implicitly, without a verbal rule). However, executive functioning is known to decline with age, leading to age-related deficits in category learning. The current thesis examines RB and NRB category learning in older adults using category sets that vary in difficulty (e.g., rule complexity, number of stimulus dimensions, salience of stimulus dimensions). In Chapter 2, older adults and younger adults completed three category sets (simple single-dimensional RB, disjunctive RB, and NRB). Older adults learned the simple, single-dimensional rules quite well. In contrast to …

The Effects Of Manual Tooth Brushing On Parotid And Submandibular/Sublingual Gland Salivary Flow Rates In Healthy Young And Older Adults, Kristen M. Trottier

Electronic Thesis and Dissertation Repository

Saliva is crucial for the maintenance of oral health. Individuals with reduced salivary flow may experience a distortion in taste, difficulty swallowing, and impaired articulation of speech. Research has shown that tooth brushing increases whole salivary flow rates in older adults. It is important to determine whether this increase results from the modulation of parotid gland salivary flow, submandibular and sublingual gland salivary flow, or both. Saliva produced from the parotid gland aids in digestive processes, while saliva secreted from the submandibular and sublingual glands promotes protection of the oral cavity. A within-subjects methodology was used to examine the effects …

Decision Making In Older Adults: A Comparison Of Delay And Probability Discounting Across, Ariana Vanderveldt

Arts & Sciences Electronic Theses and Dissertations

The value of an outcome is affected both by the delay until its receipt (delay discounting) and by the likelihood of its receipt (probability discounting). The discounting framework has greatly aided in modeling and understanding decision-making, particularly in the areas of impulsivity, but these findings have overwhelmingly been based on research with young adults. In three experiments, the current study extended the discounting framework by examining choice by older adults. Experiments 1 and 2 found that both young and older adults discounted delayed outcomes and probabilistic outcomes and that their choices were well-described by the same hyperboloid model. Both young …

Dynamic Adjustments Of Cognitive Control In Healthy Aging: A Diffusion Model Analysis, Andrew Jacob Aschenbrenner

Arts & Sciences Electronic Theses and Dissertations

The control of attention over salient yet irrelevant information is a critical component of goal-directed behavior. Compared to younger adults, older adults often produce larger interference effects in tasks which tap selective attention, a deficit that has typically been viewed as reflecting an age-related decline in attentional control processes. Interference in distinct, attentionally demanding tasks has produced different influences on the characteristics of underlying response time distributions leading to the assumption of different control mechanisms operating across various paradigms. More recently, accumulating research has shown that the magnitude of observed interference can be critically modulated by the congruency of the …

The Interaction Of Crystallized And Fluid Abilities In Aging And Speech Perception, Avanti Dey

Arts & Sciences Electronic Theses and Dissertations

In a series of studies, I examined the degree to which fluid and crystallized abilities contribute to and interact during speech perception. During the aging process, crystallized abilities (e.g., linguistic and word knowledge) are largely preserved, while fluid abilities involved in the online manipulation of information (e.g., working memory and inhibitory control) decline with age. Importantly, these two components are critical for successful speech perception and comprehension. While prior research has proposed that older adults rely on crystallized knowledge to compensate for cognitive deficits in difficult listening conditions, this hypothesis has not been directly tested. Younger and older adults completed …

Successful Sexual Aging: A Feminist Gerontological Examination Of Sexual Behavior And Health, Christina Barmon

Sociology Dissertations

As gerontology has shifted from emphasizing the problems of aging to exploring how older adults can thrive, researchers have increased their attention on new issues including sexuality and aging. A sometimes explicit, but often implicit assumption in this research, is that sex is good for you—that it is an integral part of a full and healthy life or successful aging. Although successful aging is one of the most commonly cited theories in social gerontology (Alley et al. 2010), it has not gone without criticism (Martinson and Berridge 2014). Using an unrefined successful aging framework for sex research has the potential …

Task Residual Functional Connectivity In Language And Attention Networks, Stella Tran

Psychology Theses

The present study compared network specificity between task-residual and resting state data types. Task-residual data capitalizes on the remaining variance after the mean task-related signal is removed from the time series. This study also examined how inter- and intrahemispheric connectivity (bilateral homologous regions and regions contained within the same hemisphere, respectively) within the language and attention networks change as a result of age. Task-residual functional connectivity evidenced stronger laterality of the language and attention connections and thus greater network specificity than resting state functional connectivity of the same connections. Using task-residual data may be optimal for characterizing the synchronized fluctuations …

The Phenomenology Of Masters Alpine Ski Racers: Experiencing Ski Racing In Old Age, Carly Litchfield

Electronic Thesis and Dissertation Repository

This thesis is a study of the lived experience of ten older adult alpine ski racers in their continued participation in ski racing. The aim of this study was to gain an understanding of the experiences of these older adults as they continued to compete in ski racing. Masters skiers between the ages of 69 and 82 participated in individual interviews lasting between 30 and 60 minutes. Data analysis was completed using van Manen’s phenomenological methods and the visual technique of mind mapping. The major theme that emerged was the importance of being a ski racer to participants’ identities. The …

Physical Home Environment, Personal Competencies, And Psychological Well-Being Of Community-Dwelling Older Adults: Development Of A Structural Model, Shannon Marie Trecartin

Doctoral Dissertations

This multi-manuscript dissertation focuses on the relationships between the physical home environment, personal competencies, and psychological well-being among older adults living in community settings. The ecological model of aging serves as the guiding theoretical framework for the exploration and design of the subsequent studies. The first paper is a critical review of the literature. Results suggest that there is little consistency in the measurement of the physical home environment across studies. Also, more research is needed to clarify the relationships between the three major constructs and to expand the area of study to U.S. populations. Finally, some support exists to …

Early Parental Loss, Socioeconomic Stressors, And Health In Later Life: Evidence For Gender Disparity, Rong Fu

Open Access Dissertations

Drawing from the stress process model and the cumulative disadvantage theory, this dissertation examined how childhood and later life stressors affected cognitive and subjective health in older adults. Using three main articles, this dissertation investigated (1) the effect of early parental loss on cognitive well-being in Chinese oldest old; (2) the effect of intergenerational socioeconomic mobility on cognitive and subjective health in advanced age; and (3) the effect of different dimensions of socioeconomic status and perceived financial strain on subjective health in later life. Data were derived from the 2002 and 2005 waves of the Chinese Longitudinal Healthy Longevity Survey. …

Functional Studies Of The Human Telomerase Holoenzyme, Mohammed E. Sayed

Bioengineering Dissertations

Telomeres are the DNA structures that cap the ends of linear chromosomes. In humans, telomeres are composed of the hexameric repeats TTAGGG. The reverse transcriptase, telomerase maintains the telomeres by adding the TTAGGG repeats to the chromosomes during cell division. In the absence of telomerase, telomere length limits the self-renewal capabilities of cells. Telomerase is expressed in approximately 90% of all human cancers, making it an almost universal therapeutic target as well as an important player in the progression from healthy to cancerous cell. The biophysical studies discussed in this thesis focus on expanding the understanding of the function and …

Effects Of Attachment Style, Coping Strategy, Social Support And Spirituality On Parental Grief Among Older Chinese Parents : Structural Equation Modeling., Yongqiang Zheng

Electronic Theses and Dissertations

Most modern grief theories and clinical working models are constructed in the context of Western culture, and the effectiveness or explanatory power of those theories and models have not been fully tested in other cultures, especially through a more complex interactive model. The current study focuses on the role of attachment style, coping strategy, social support and spirituality on older bereaved parents’ grief. It also explores if differences in age, gender, causes of the child’s death, time since the death have a differential effect on parental grief. The purpose of this study was to test the main factors effectively mediating …

Moderation Analysis Of Bowel Function Among Nutrients And Physical Function Or Depression, As Well As Whether Bowel Function Is Related To Cognition In Older Adults, Jessie Alwerdt

USF Tampa Graduate Theses and Dissertations

As we age, the risk for gut issues, such as smooth muscle tone, may be an underlying indirect or direct cause or risk factor for many age-related issues, such as frailty. Consequences of decreased motility and depleted epithelial barrier may result in nutrient deficiencies that may increase the risk for malnutrition (Brownie, 2006). Further, there is increasing evidence that there is a gut-brain-axis relationship that may influence cognition and mental health issues, such as depression and anxiety. While there are relationships established, the interconnections of these factors have yet to be fully understood.

This dissertation examined several relationships specific to …

Essays On The Well-Being Of An Aging Population, Alice Zulkarnain

Dissertations, Theses, and Capstone Projects

This dissertation consists of three essays that examine health and labor issues among the middle aged and elderly.

Chapter 1. A Delayed Retirement Policy and Male Labor Supply: Evidence from the Entire Dutch Population

This chapter examines the labor supply effects of a national delayed retirement policy introduced in the Netherlands in 2009. The policy offers a reduction in taxes on labor income for each year after the age of 62 in which a person worked. I estimate the average effect of the policy on male labor supply as well as its responsiveness to the size of the incentive. Comparing …

Modeling Non-Linear Relationships Between Dna Methylation And Age: The Application Of Regularization Methods To Predict Human Age And The Implication Of Dna Methylation In Immunosenescence, Nicholas Johnson

Public Health Theses

Background: Gene expression is regulated via highly coordinated epigenetic changes, the most studied of which is DNA methylation (DNAm). Many studies have shown that DNAm is linearly associated with age, and some have even used DNAm data to build predictive models of human age, which are immensely important considering that DNAm can predict health outcomes, such as all-cause mortality, better than chronological age. Nevertheless, few studies have investigated non-linear relationships between DNAm and age, which could potentially improve these predictive models. While such investigations are relevant to predicting health outcomes, non-linear relationships between DNAm and age can also add to …

Wideband Acoustic Immittance And Dpoae Changes In Older Adults, Mandy M. Williams

Dissertations, 2014-2019

This study examined the effect of middle ear aging in adults using wideband acoustic immittance (WAI) measures. WAI and traditional 226 Hz tympanometry were measured in 25 young adult ears (ages 18-25) and 26 older adult ears (ages 50-71) with normal middle ear status. While minimal differences between older and younger adults were observed with 226 Hz tympanometry, significant age effects were seen with WAI measures. The older adults demonstrated a statistically significant increase in middle ear absorbance at lower frequencies (226-1,260 Hz) and decreased absorbance at higher frequencies (4,000-5,040 Hz) compared to the younger adult group. While the effect …

Examining Racial Differences Among Predictors Of Home And Community-Based Service Use And Choice And Control In Older Adults In The Money Follows The Person Program In Connecticut, Chanee Darnell Fabius

Doctoral Dissertations

The purpose of this study was to explore racial differences in home and community-based service (HCBS) use and perceived choice and control in frail elders ages 65 and older participating in the Money Follows the Person (MFP) demonstration program in Connecticut using the Andersen Behavioral Model of Health Service Utilization (1995). The comparison of Black and White program participants provides insight both for clinicians who work directly with frail elders and for researchers who seek to contribute to the gerontological field. This dissertation used secondary data collected from quality of life (QOL) interviews of (N=659) MFP participants who have transitioned …

Investigation Of Neural Mechanisms Of Grip Relaxation, Binal Motawar

Theses and Dissertations

Neural mechanisms for grip relaxation are relatively unknown and understudied, as compared to mechanisms for grip initiation. Yet, termination of motor activity is as important as initiation in daily function. This knowledge gap presents incomplete understanding of neural control of hand function and its impairment with aging and neurologic disorders. The purpose of this dissertation was to identify and examine neural mechanisms of grip relaxation in healthy young adults, with aging, and in chronic stroke survivors. A series of experiments in healthy young adults showed that the relaxation from a maximum power grip was mediated by increase in the short-interval …

Dance And Well-Being In Older Adult Communities: Exploring Efficacy As A Mediator, Beth M. Mcgowan

Honors Thesis

As the population of older adults expands, it becomes increasingly important to develop effective interventions to ensure high levels of well-being. Previous research in a variety of populations has shown that dance produces broad benefits including improving physical mobility, social relationships, autonomy, and self-image. Given this, the present study attempted to clarify the mechanisms through which dance might lead to these improvements. Specifically, this research examined the role of self-efficacy, or beliefs that one can accomplish certain tasks, have in explaining the psychological benefits of dance. I hypothesized that when dance is a social activity it instills a sense of …