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Age Differences In Hippocampal Glutamate Modulation During Associative Learning And Memory: A Proton Functional Magnetic Resonance Spectroscopy (1h Fmrs) Study, Chaitali Anand
Wayne State University Dissertations
Episodic and associative memory decline is one of the earliest cognitive impairments in normal aging and among the defining cognitive features of Alzheimer’s disease (AD). Since, age-related cognitive decline gradually devolves into AD, with neuropathology preceding cognitive changes by many years, the identification of biomarkers of early disease progression is crucial. Reduction in glutamate, the main excitatory neurotransmitter involved in associative memory, in key brain regions such as the hippocampus, has been theorized as one of the cellular mechanisms underlying cognitive decline in aging and AD. A few neuroimaging studies that demonstrated a link between older adults’ weaker cognitive performance …
Change In Processing Speed And Its Associations With Cerebral White Matter Microstructure, Muzamil Arshad
Change In Processing Speed And Its Associations With Cerebral White Matter Microstructure, Muzamil Arshad
Wayne State University Dissertations
The decline of cognition with age is one of the most feared aspects of aging, while the slowing of responses, or reduced processing speed, is one of the most reliable aspects of aging. Slowing of processing has been hypothesized to affect other domains of cognition as well. Despite the well-known slowing-age relationship and central position processing speed plays in theories of cognitive aging the neurobiological mechanisms which underpin slowing is unclear. If we could identify the biology associated with processing speed we could then attempt to develop interventions to mitigate the effects of age on those variables. In turn we …
Investigating The Role Of Dna Polymerase Beta In The Aging Phenotype Of Down Syndrome, Aqila Ahmed Ahmed
Investigating The Role Of Dna Polymerase Beta In The Aging Phenotype Of Down Syndrome, Aqila Ahmed Ahmed
Wayne State University Dissertations
Down syndrome (DS) is a chromosomal condition characterized by accelerated aging that has yet to be directly linked to a DNA repair defect. Reduced PolB and unrepaired damage from oxidative stress observed in DS, point toward defective base excision repair (BER). In this study, we report that low PolB transcript correlates with increased markers of senescence. The gene dosage effect of Trisomy 21 is likely the source for PolB downregulation. We show that the HSA21-localized miR-155 overexpression correlates with a decrease in Creb1 and PolB, thus establishing a putative regulatory pathway. Data from the DS mouse model, Ts65Dn, reveal low …
The Impact Of Age On Workplace Motivation: A Person-Centered Perspective, Keith Lynn Zabel
The Impact Of Age On Workplace Motivation: A Person-Centered Perspective, Keith Lynn Zabel
Wayne State University Dissertations
The present study used the person-centered approach to examine how profiles based upon six different age conceptualizations differentially impact workplace motivation. In the first known study to examine all conceptualizations of age simultaneously, results suggested the age conceptualizations of subjective age and health significantly impact growth motives for older workers, but not social or security motives. Results suggest social motives are influenced more by chronological age as opposed to other conceptualizations of age. Implications for practitioners in designing and implementing HR activities (e.g., succession planning) and researchers in utilizing all the conceptualizations of age and studying workplace interventions are discussed.
The Impact Of Folate Restriction On Cancer And Aging: A Mechanistic Analysis, Safa Beydoun
The Impact Of Folate Restriction On Cancer And Aging: A Mechanistic Analysis, Safa Beydoun
Wayne State University Dissertations
Aging is a multifactorial process associated with alterations in several physiological functions. It increases susceptibility to disease and ultimately results in mortality. Since the associated diseases of aging are highly prevalent in the geriatric population, targeting the aging process as a whole may provide a better way to delay these age related diseases, in turn delaying aging. Various interventions have been shown to delay aging and age related diseases. They impact a major nutrient sensing pathway, mTOR. mTOR signaling is altered in many cancers and its downregulation was shown to delay aging. Other interventions extend lifespan by altering the one …
Changes In Cerebral White Matter, Vascular Risk And Cognition Across The Adult Lifespan, Andrew Robert Bender
Changes In Cerebral White Matter, Vascular Risk And Cognition Across The Adult Lifespan, Andrew Robert Bender
Wayne State University Dissertations
Numerous studies over the past decade have used diffusion tensor imaging (DTI) to examine associations between age, diffusion and anisotropy measures of cerebral white matter (WM), and cognitive performance. However, few have examined relationships between intra-individual change in DTI measures of WM and cognitive function. It is possible that the extant cross-sectional findings are a poor representation of age-related change in WM and cognition. The present study used latent difference-score modeling (LDM) to assess change over two years in DTI indices fractional anisotropy (FA), radial diffusivity (DR), axial diffusivity (DA) and mean diffusivity (MD). In addition, we examined the effects …
Effects Of Altering The Peroxisomal Redox State In Models Of Degenerative Disease, Courtney Rose Giordano
Effects Of Altering The Peroxisomal Redox State In Models Of Degenerative Disease, Courtney Rose Giordano
Wayne State University Dissertations
Peroxisomes are important regulators of cellular redox balance and function as a signaling platform to regulate anti-aging metabolic and communication networks. In addition the organelle has emerged as a major player in maintaining cellular ROS at an optimal level. At such levels, these ROS are involved in initiation of signaling cascades and that produce an array of anti-aging and disease processes. However, as cells age over time, ROS amass within the peroxisome and elsewhere in the cell. This leads to an imbalance in oxidative homeostasis and results in compromised signaling networks. The goal of this dissertation was to treat disease …
Accumulation Of Subcortical Iron As A Modifier Of Volumetric And Cognitive Decline In Healthy Aging: Two Longitudinal Studies, Ana Marie Daugherty
Accumulation Of Subcortical Iron As A Modifier Of Volumetric And Cognitive Decline In Healthy Aging: Two Longitudinal Studies, Ana Marie Daugherty
Wayne State University Dissertations
Accumulation of non-heme iron in the brain has been theorized as a cellular mechanism underlying global neural and cognitive decline in normal aging and neurodegenerative disease. Relatively few studies of brain iron in normal aging exist and extant studies are almost exclusively cross-sectional. Here, I estimated iron content via T2* and measured volumes in several brain regions in two independent samples of healthy adults. The first sample (N = 89) was measured twice with a two-year delay; and the second sample (N = 32) was assessed four times over a span of 7 years. Latent models estimated change in iron …
Assessment Of The Semantic Knowledge Network In Older Adults With Familial History Of Alzheimer's Disease, Erin Marie Holcomb
Assessment Of The Semantic Knowledge Network In Older Adults With Familial History Of Alzheimer's Disease, Erin Marie Holcomb
Wayne State University Dissertations
Current techniques for the treatment of Alzheimer's disease rely on early implementation, which necessitates the need for accurate and early identification of individuals most at risk for future cognitive decline. Research has demonstrated the usefulness of examining the temporal gradient for long-term semantic knowledge in identification of such individuals. The assessment of the temporal gradient within varying levels of knowledge specificity, however, has received considerably less attention. In this study, we aimed to contrast accuracy and reaction times for semantic memory tasks tapping multiple dimensions of semantic specificity from multiple time epochs in adult children with and without a parental …
The Influence Of Gender And Aging On The Neural Circuitry Supporing Facial Emotion Processing In Adults With Major Depressive Disorder, Emily Briceno
The Influence Of Gender And Aging On The Neural Circuitry Supporing Facial Emotion Processing In Adults With Major Depressive Disorder, Emily Briceno
Wayne State University Dissertations
Major Depressive Disorder (MDD) is associated with decrements in facial emotion processing (FEP). Previous studies investigating the neural substrates of these decrements have often reported hyperactivity of emotion processing circuitry. Neural circuitry supporting FEP has been shown to be different between healthy men and women, and between young and elder adults. However, no prior studies have investigated how gender and aging affect emotion processing circuitry in individuals with MDD. The present study aimed to investigate the influence of gender and aging on emotion processing circuitry in MDD. One hundred-ten adults, grouped into subgroups according to MDD status, gender, and age …
Predicting Vision Loss In Healthy Aging With Manganese-Enhanced Mri Of The Rat Eye, David Bissig
Predicting Vision Loss In Healthy Aging With Manganese-Enhanced Mri Of The Rat Eye, David Bissig
Wayne State University Dissertations
In healthy aging, visual function declines throughout adulthood. Age-related changes in neuronal ion homeostasis -- specifically, increased Ca2+ influx through L-type voltage gated calcium channels (L-VGCCs) -- are believed to contribute to certain functional declines, but this possibility has not yet been tested in the neural retina. In young, mid- and old adult Long-Evans rats, we compared visual function (optokinetic tracking), as well as retinal physiology and eye morphology (Mn2+-enhanced MRI (MEMRI), which uses neuronal Mn2+ uptake as a marker of Ca2+ influx). We documented significant age-related decreases in visual performance and increases in retinal ion influx. We confirmed that …