Medicine and Health Sciences Commons^™

An Ewas Of Dementia Biomarkers And Their Associations With Age, African Ancestry, And Ptsd, Mark W. Miller, Erika J. Wolf, Xiang Zhao, Mark W. Logue, Sage E. Hawn

Psychology Faculty Publications

Background

Large-scale cohort and epidemiological studies suggest that PTSD confers risk for dementia in later life but the biological mechanisms underlying this association remain unknown. This study examined this question by assessing the influences of PTSD, APOE ε4 genotypes, DNA methylation, and other variables on the age- and dementia-associated biomarkers Aβ40, Aβ42, GFAP, NfL, and pTau-181 measured in plasma. Our primary hypothesis was that PTSD would be associated with elevated levels of these markers.

Methods

Analyses were based on data from a PTSD-enriched cohort of 849 individuals. We began by performing factor analyses of the biomarkers, the results of which …

The Impact Of Alzheimer Disease On Semantic Knowledge, Maileen G. Ulep

UNLV Theses, Dissertations, Professional Papers, and Capstones

The research furthers the understanding of the impact of Alzheimer disease (AD) on cognition and the organization of semantic knowledge in the brain, which might contribute to the development of diagnostic and staging tools, and interventions to palliate cognitive deficits. The disruption of semantic knowledge in AD is well documented in the literature. Much of the existing research focuses on the general impact AD has on semantic knowledge. This study explores the impact of AD on specific domains of knowledge, chiefly, living kinds and artifacts, critical to ordinary functioning. The content, organization and structure of the investigated domains of knowledge …

The Effects Of Physical Function And Genetics On Cognition And Blood Biomarkers In Individuals At-Risk For Alzheimer’S Disease And Related Dementias, Joshua Louis Gills

Graduate Theses and Dissertations

Alzheimer’s disease and related dementia (ADRD) rates are expected to triple by the year 2050. Early detection and specific mitigation efforts are warranted to blunt the alarming rate. Physical function (PF) declines with age, but higher physical function is associated with better cognitive functioning in middle-to- older age individuals. Moreover, greater physical activity (PA) is associated with better global cognition; however, Apoliporotein e4 carriers may not gain the same benefits with exercise. Additionally, plasma phosphorylated tau 217 (p-tau217) has been identified as a novel diagnostic ADRD biomarker which needs further research to examine associations with risk factors. Therefore, the aims …

Examining The Mental Health Of Older Hispanic/Latino Adults: Relationship Between Psycho-Social-Cultural Factors And Depressive Symptomatology, Anna Prado

Theses and Dissertations

The most prevalent disorders affecting the older adult population worldwide are dementia and depression. Ethnic minorities are disproportionately more likely to be affected by these two distressing and debilitating conditions. Hispanic/Latino older adults encounter numerous psycho-social-cultural factors that influence health behaviors, attitudes, and beliefs in positive and negative ways. Presently, research on the influence of these factors on Hispanic/Latino mental health is highly inconsistent. The purpose of the present study is to examine the relationship between selected psycho-social-cultural factors and the mental health of older Hispanic/Latino adults. Using data from the Health and Retirement Study, the association between the Hispanic/Latino …

Comparison Of Longitudinal Changes In Resting State Functional Magnetic Resonance Imaging Between Alzheimer’S And Healthy Controls, Berk Can Yilmaz

Theses

Resting State Functional Magnetic Resonance Imaging (rs-fMRI) is a technique that is widely used for analyzing brain function using different approaches and methods. This study involves rs-fMRI analysis of Blood Oxygenation Level Dependent (BOLD) signals acquired from Alzheimer’s disease (AD) Patients and Healthy Controls (HC). Each subject in the study had both functional and anatomical images with at least one rs-fMRI scan with their Anatomical (T1) scans. Previous rs-fMRI studies have demonstrated that AD shows differences in Amplitude of Low Frequency (<0.1 Hz) Fluctuations (ALFF), and Regional Homogeneity (ReHo) measures according to HCs.

The aim of the study is to investigate individual and group level differences using ReHo and mALFF related …

Basal Forebrain Volume Reliably Predicts The Cortical Spread Of Alzheimer's Degeneration, Sara Fernández-Cabello, Martin Kronbichler, Koene R.A. Van Dijk, James A. Goodman, R. Nathan Spreng, Taylor W. Schmitz

Brain and Mind Institute Researchers' Publications

© The Author(s) (2020). Published by Oxford University Press on behalf of the Guarantors of Brain. Alzheimer's disease neurodegeneration is thought to spread across anatomically and functionally connected brain regions. However, the precise sequence of spread remains ambiguous. The prevailing model used to guide in vivo human neuroimaging and non-human animal research assumes that Alzheimer's degeneration starts in the entorhinal cortices, before spreading to the temporoparietal cortex. Challenging this model, we previously provided evidence that in vivo markers of neurodegeneration within the nucleus basalis of Meynert (NbM), a subregion of the basal forebrain heavily populated by cortically projecting cholinergic neurons, …

Memory-Based Viewing: A Potential Marker Of Pathological Aging, Jenna Blujus

Theses and Dissertations

Markers of cognitive impairment are needed to distinguish normal from pathological aging prior to the onset of clinical symptomology to improve Alzheimer’s disease (AD) treatment or prevention efforts. AD pathology is believed to develop years or even decades prior to diagnosis in medial temporal lobe subregions that provide input to the hippocampus (Braak & Braak, 1991), disrupting the ability of the hippocampus to bind individual elements of an experience to form cohesive memory representations. Eye movement behavior is a sensitive index of learning and effects of memory on eye movements have been shown to emerge rapidly (within 500-750ms of stimuli …

Memory-Based Viewing: A Potential Marker Of Pathological Aging, Jenna Blujus

Theses and Dissertations

Markers of cognitive impairment are needed to distinguish normal from pathological aging prior to the onset of clinical symptomology to improve Alzheimer’s disease (AD) treatment or prevention efforts. AD pathology is believed to develop years or even decades prior to diagnosis in medial temporal lobe subregions that provide input to the hippocampus (Braak & Braak, 1991), disrupting the ability of the hippocampus to bind individual elements of an experience to form cohesive memory representations. Eye movement behavior is a sensitive index of learning and effects of memory on eye movements have been shown to emerge rapidly (within 500-750ms of stimuli …

Longitudinal Alzheimer's Degeneration Reflects The Spatial Topography Of Cholinergic Basal Forebrain Projections, Taylor W. Schmitz, Marieke Mur, Meghmik Aghourian, Marc Andre Bedard, R. Nathan Spreng

Brain and Mind Institute Researchers' Publications

© 2018 The Author(s) The cholinergic neurons of the basal forebrain (BF) provide virtually all of the brain's cortical and amygdalar cholinergic input. They are particularly vulnerable to neuropathology in early Alzheimer's disease (AD) and may trigger the emergence of neuropathology in their cortico-amygdalar projection system through cholinergic denervation and trans-synaptic spreading of misfolded proteins. We examined whether longitudinal degeneration within the BF can explain longitudinal cortico-amygdalar degeneration in older human adults with abnormal cerebrospinal fluid biomarkers of AD neuropathology. We focused on two BF subregions, which are known to innervate cortico-amygdalar regions via two distinct macroscopic cholinergic projections. To …

The Famous Names Discrimination Task As A Biomarker Of Alzheimer's Disease Risk: An Erp Study, Elizabeth Rose Paitel

Master's Theses (2009 -)

Current ERP research emphasizes age- and pathology-related declines in neural processing in the form of attenuated amplitudes and prolonged latencies. Notably, there is a gap in the ERP literature regarding neural processing trajectories in the time between healthy young adulthood and clinical MCI/AD samples. fMRI research, however, has demonstrated periods of increased, compensatory activation in healthy, cognitively intact APOE ɛ4 carriers both during resting state and event-related tasks (Bondi, Houston, Eyler, & Brown, 2005; Evans et al., 2014; Filippini et al., 2009; Rao et al., 2015), consistent with compensatory theories of cognitive aging (Cabeza, 2002; Park & Reuter-Lorenz, 2009; Reuter-Lorenz …

Reciprocity: Caring For America's Caregivers, Courtney Dunn

The Downtown Review

Should families be forced to choose between the health of a caregiver and patient? Through the eyes of a woman caring for her husband with Alzheimer's disease, we see that family caregivers suffer tremendous amounts of stress while caring for the patient. Despite the time and efforts required to care for someone with Alzheimer's disease, people every day choose this as an alternative to out-of-home care. This often leads to depression, anxiety, and physical stress which can result in series medical issues. Considering the increase of people with Alzheimer's disease in the United States, this article argues that support programs …

The Semantic Memory Imaging In Late Life Pilot Study, Michael Adam Sugarman

Wayne State University Dissertations

Introduction: Several functional magnetic resonance imaging (fMRI) studies have analyzed the famous name discrimination task (FNDT), an uncontrolled semantic memory probe requiring discrimination between famous and unfamiliar individuals. Completion of this simple task recruits a semantic memory network that has shown utility in determining risk for Alzheimer's disease (AD). Specific semantic memory probes using biographical information associated with famous individuals may build on previous findings and yield superior information regarding risk for AD.

Method: Sixteen cognitively intact elders completed the FNDT and two novel tasks during fMRI: Categories (matching famous individuals to occupational categories) and Attributes (matching famous individuals to …

The Effect Of Acute Lps-Induced Immune Activation And Brain Insulin Signaling Disruption In A Diabetic Model Of Alzheimer's Disease, Andrew Scott Murtishaw

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer's disease (AD) is a neurodegenerative disorder marked by progressive cognitive impairments and pathological hallmarks that include amyloid plaques, neurofibrillary tangles, and neuronal loss. Several well-known mutations exist that lead to early-onset familial AD (fAD). However, these cases only account for a small percentage of total AD cases. The vast majority of AD cases are sporadic in origin (sAD) and are less clearly influenced by a single mutation but rather some combination of genetic and environmental risk.

The etiology of sAD remains unclear but numerous risk factors have been identified that increase the chance of developing AD. Among these risk …

Examining The Ability Of The Halstead -Reitan Battery And The Wide Range Achievement Test To Utilize Severity In Discriminating Among Alzheimer's Dementia Patients, Gina Gibson-Beverly

Doctoral Dissertations

Measuring change in cognitive status is essential for the diagnosis, prognosis, and treatment of brain dysfunction. Psychological abilities are differentially affected by brain dysfunction severity, as some abilities are more vulnerable to brain dysfunction than others. Neuropsychological assessments can be viewed as a continuum of "hold" and "don't hold" tests. "Hold" tests assess abilities that remain stable in spite of brain dysfunction, while "don't hold" tests measure skills that are significantly compromised by brain impairment. The present study ranks the Halstead-Reitan Battery (HRB) and the Wide Range Achievement Test (WRAT) subtests based on their ability to discriminate between two levels …

Structural Mri Discriminates Individuals With Mild Cognitive Impairment From Age-Matched Controls: A Combined Neuropsychological And Voxel Based Morphometry Study, Mehul A. Trivedi, Allison K. Wichmann, Britta M. Torgerson, Michael A. Ward, Taylor W. Schmitz, Michele L. Ries, Rebecca L. Koscik, Sanjay Asthana, Sterling C. Johnson

Brain and Mind Institute Researchers' Publications

Background: Several previous studies have reported that amnestic mild cognitive impairment (aMCI), a significant risk factor for Alzheimer's disease (AD), is associated with greater atrophy in the medial temporal lobe (MTL) and posterior cingulate gyrus (PCG). Method: In the present study, we examined the cross-sectional accuracy (i.e., the sensitivity and specificity) of voxel-based morphometry (VBM) in discriminating individuals with MCI (n = 15) from healthy age-matched controls (n = 15). In addition, we also sought to determine whether baseline GM volume predicted aMCI patients that converted to AD from those that did not approximately 2 years after the baseline visit. …