Medicine and Health Sciences Commons^™

Monitoring Intraventricular Hemorrhage In Preterm Infants, Lilian Mn Kebaya

Electronic Thesis and Dissertation Repository

Germinal Matrix-Intraventricular hemorrhage (GMH-IVH) remains a significant cause of adverse neurodevelopmental outcomes in preterm infants. Current management options for GMH-IVH rely on serial 2-dimensional cranial ultrasound (2D cUS) ventricular measurements and clinical signs. A need exists for reliable biomarkers to aid in the early detection of posthemorrhagic ventricular dilatation (PHVD) and cerebral palsy (CP). We incorporated 3-dimensional cranial US (3D cUS) and functional infrared spectroscopy (fNIRS) to monitor ventricle volumes (VV) and spontaneous functional connectivity (sFC) in preterm infants with GMH-IVH. Infants with severe GMH-IVH who underwent cerebrospinal fluid diversion showed larger VV, which correlated with decreased sFC. Our findings …

Transcranial Direct Current Stimulation Of Frontal/Occipital Cortices Modulates Neural Correlates Of Cognition In Healthy Young Adults, Yasra Arif

Theses & Dissertations

An exponential rise in the use of transcranial direct current stimulation (tDCS) to modify the human brain and behavior has been observed over the last 20 years, with studies often yielding mixed outcomes. Such heterogeneity is partially attributed to the lack of a concise understanding of the underlying mechanisms. Though considered to exert modulatory effects by changing neuronal membrane polarization and synaptic efficacy, the interactive effects of offline tDCS and the neural underpinnings of cognition, both at the regional and network-level, are yet to be fully understood. Using High-Definition tDCS (HD-tDCS), Magnetoencephalography (MEG), a range of well-established cognitive paradigms, and …

Empowering Nurses To Recognize Post-Stroke Depression In The African American Community, Deidra Frisbie, Robin Simon

Doctor of Nursing Practice Projects

African Americans (AA) have the highest prevalence of stroke and death compared to other racial groups in the United States. Post-stroke depression (PSD) affects approximately 1/3 of all stroke patients and is underdiagnosed in the African American community.

Aim: By using a mHealth mobile app and a Psychiatry provider list at discharge, PSD can be identified, and interventions initiated, thus decreasing the sequela of PSD in AA.

Methods: Nurses were provided education on PSD, expressions of depression in African-Americans, cultural humility, implicit bias, and the importance of the nurse's role in developing a therapeutic relationship.

Results: Quantitative analysis revealed the …

Contributions Of Specific Retinal Circuits And Their Respective Projections To Visual Behaviors, Jenna Mackenzie Krizan

Arts & Sciences Electronic Theses and Dissertations

The survival of a species is inextricably linked to its ability to successfully navigate and interact with its surroundings, whether to seek safety from predators or gain sustenance from prey. Both functions are performed by mice, guided by vision, and rely on intricate processing in the retina and subcortical targets in the brain. This dissertation addresses how specific features of the visual environment and specific retinal ganglion cell circuits that sample a particular space in the visual environment are used to guide efficient predation in mice.Recent studies have begun to link the ability to detect, track, and ultimately capture prey …

The Bidirectional Relationship Between The Circadian Clock And Alzheimer’S Disease, Patrick Sheehan

Arts & Sciences Electronic Theses and Dissertations

The circadian clock and inflammation have a well-described bidirectional relationship in the peripheral immune system: the circadian clock regulates inflammatory responses, but inflammation also impacts oscillatory gene transcription controlled by the clock. The purpose of this thesis work is to understand if manipulation of the circadian clock can impact Alzheimer’s disease pathology, and if pathology itself can alter the circadian clock and its outputs. Here, I show that astrocyte-specific disruption of the circadian clock via deletion of the clock gene Bmal1 surprisingly decreased intra-neuronal protein pathologies. Further investigation found that deletion of the circadian clock resulted in a transcriptomic profile …

The Effects Of Nmda Antagonism On Neuronal Activity And Neurovascular Coupling In Non-Human Primate Cortex, Benjamin Thomas Acland

Arts & Sciences Electronic Theses and Dissertations

The N-methyl-D-aspartate receptor (NMDAR) plays a variety of important roles in the development and function of primate central nervous systems. This thesis describes three nonhuman primate studies that, together, demonstrate that pharmacologically reducing NMDAR activity not only causes dramatic changes in neural activity in cortex, but also changes the relationship between that activity and a key signal often used as its proxy in human studies, the blood-oxygen-level-dependent (BOLD) signal. The first study reveals that NMDA antagonism is sufficient to induce powerful low-frequency modulation of spiking activity and extracellular local field potential (LFP) and discusses the implications of this finding for …

Sik3 & Wnk Signals Through Fray To Regulate Glial K+ Buffering And Seizure Susceptibility In Drosophila Models Of Hyperexcitability, Lorenzo Laronn Lones

Arts & Sciences Electronic Theses and Dissertations

K+ homeostasis is important for maintaining healthy, physiological levels of neuronal activity. Glial cells play a central role in maintaining homeostatic ion gradients. In previous work from our lab, we unravel a glial K+ buffering program that is centered on a key kinase, salt-inducible kinase 3 (SIK3). SIK3-HDAC4 signaling in glial regulates the transcription of channels and transporters involved in water and ion transport. Defects in this pathway lead to peripheral nerve edema, neuronal hyperactivity, and seizure sensitivity. In an hyperexcitability mutant, eag Shaker, we show this pathway is downregulated and genetic activation suppresses seizure behavior. In this thesis, I …

Extensive Behavioral Phenotyping Of Williams Syndrome Locus Relevant Mouse Models To Assess Contributions Of Oxytocin And Gtf2ird1, Kayla Rose Nygaard

Arts & Sciences Electronic Theses and Dissertations

The Williams Syndrome Critical Region (WSCR) at chromosome 7q11.23 provides a unique opportunity to untangle the relationship between genotype and phenotype in complex behaviors, from fear and anxiety to sociability and sensorimotor processing. Copy number variations (CNVs) in this region result in two syndromes, Williams Syndrome (WS) and Duplication 7q11.23 Syndrome (Dup7), which display phenotypes that may align, indicating a common disruption of a system, or diverge, reflecting an underlying gene dosage-dependent effect. While case studies of atypical deletions resulting in WS have implicated telomeric genes Gtf2ird1 and Gtf2i in the cognitive and behavioral profiles of WS, proving causation requires …

Data-Driven Neuroanatomical Subtypes In Various Stages Of Schizophrenia: Linking Cortical Thickness, Glutamate, And Language Functioning, Liangbing Liang

Electronic Thesis and Dissertation Repository

The considerable variation in the spatial distribution of cortical thickness changes has been used to parse heterogeneity in schizophrenia. We aimed to recover a ‘cortical impoverishment’ subgroup with widespread cortical thinning. We applied hierarchical cluster analysis to cortical thickness data of three datasets in different stages of psychosis and studied the cognitive, functional, neurochemical, language and symptom profiles of the observed subgroups. Our consensus-based clustering procedure consistently produced a subgroup characterized by significantly lower cortical thickness. This ‘cortical impoverishment’ subgroup was associated with a higher symptom burden in a clinically stable sample and higher glutamate levels with language impairments in …

Dimensionality Of Natural Auditory Scene Perception: A Factor Analysis Study, Margaret A. Mcmullin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Theories of auditory and visual scene analysis suggest the perception of scenes relies on the identification and segregation of objects within it, resembling a detail-oriented processing style, but it is possible that a global-oriented process also occurs while evaluating auditory scenes. There is evidence for global properties that enable rapid recognition of visual scenes, even without recognizing the individual objects comprising the scene. It is our understanding that a similar line of research has not been explored in the auditory domain; therefore, we evaluated the contributions of high-level global and low-level acoustic information to auditory scene perception. A secondary aim …

Markers Of Neuroinflammatory And Degenerative Processes In Professional Athletes With Traumatic Encephalopathy Syndrome, Brooke Conway Kleven

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: The clinical criteria for Traumatic encephalopathy syndrome (ccTES) were developed to improve the diagnosis of Chronic traumatic encephalopathy (CTE). This study aimed to determine whether there was an association between a clinical diagnosis of Traumatic encephalopathy syndrome (TES) and changes in serum biomarkers, balance, neuroimaging, and cognition among athletes in the Professional Athletes Brain Health Study (PABHS).Methods: Of the cohort, 130 professional fighters met age or retirement criteria and went to a consensus conference, with 52 fighters (40%) meeting the criteria for TES. A generalized linear model with generalized estimating equations was utilized to assess the odds of disease …

A Multiple Input Multiple Output Framework For The Automatic Optical Fractionator-Based Cell Counting In Z-Stacks Using Deep Learning, Palak Dave

USF Tampa Graduate Theses and Dissertations

Quantifying cells in a defined region of biological tissue is critical for many clinical and preclinical studies, especially in pathology, toxicology, cancer, and behavior. Unbiased stereology is the state-of-art method for quantification of the total number and other morphometric parameters of stained objects in a defined region of biological tissue. As part of a program to develop accurate, precise, and more efficient automatic approaches for quantifying morphometric changes in biological tissue, our group has shown that both deep learning-based and hand-crafted algorithms can estimate the total number of histologically stained cells at their maximal profile of focus in extended depth …

Postexercise Executive Function Benefits And Cerebral Blood Flow: In The Lab And At Home, Benjamin Tari

Electronic Thesis and Dissertation Repository

A single bout of aerobic exercise improves executive function; however, the mechanism, or mechanisms, supporting this improvement remain unclear. One candidate mechanism is an exercise-mediated increase in cerebral blood flow (CBF) that enhances the efficiency of executive-related frontoparietal networks. To evaluate the link between exercise, CBF and executive function, three separate experiments were conducted. In the first study, separate 10-min sessions of moderate-to-heavy-intensity aerobic exercise, and a hypercapnic environment (i.e., 5% CO₂) were implemented. The hypercapnic condition was included because it increases CBF independent of the metabolic demands of exercise. The second study investigated whether exercise intensity-specific changes …

Contributions Of Asymmetry And Instability To Transfer And Retention Following Locomotor Adaptation, Daniel L. Gregory

Doctoral Dissertations

Gait asymmetry resulting from neurological injury is more costly and less stable than healthy gait. Split-belt treadmills, which drive limbs at different speeds, lead to spatial and temporal gait asymmetries, and perturb walking balance, have been used to study locomotor adaptability and learning related to asymmetry and stability. This knowledge may be leveraged to design more effective rehabilitation protocols. In experiment 1, we asked how constraining stride-rates away from preferred during split-belt walking influences learning revealed in a retention test. We found that constraints to stride rate during asymmetric walking uncovered the capacity to leverage redundant degrees-of-freedom for walking control, …

A Paraventricular Thalamo-Accumbal Circuit Necessary For Behavioral Inhibition Is Dysfunctional During Opioid Use And Dependence, Kelsey M. Vollmer

MUSC Theses and Dissertations

Suppression of dangerous or inappropriate reward-motivated behaviors is critical for survival, whereas therapeutic or recreational opioid use can unleash detrimental behaviors and opioid use disorder (OUD). Nevertheless, the neuronal systems that suppress maladaptive motivated behaviors remain unclear, and whether opioids disengage those systems is unknown. Here, we investigate the posterior paraventricular thalamus (pPVT) as a behavioral mediator due to its strong connectivity with brain structures important for reward processing, such as the nucleus accumbens (NAc). We and others have found pPVT-NAc neuronal activity is inhibited during reward seeking, but activated when such behaviors would be inappropriate, such as during stress …

The Differential Effects Of Acoustic Discriminations On Operant Learning Performance And Neurogenesis In Male And Female Zebra Finches, Kristena L. Newman

Dissertations, Theses, and Capstone Projects

Adult neurogenesis, the creation of new neurons, occurs throughout the lifespan in most organisms. However, though neuronal proliferation occurs daily, most of these neurons do not survive to become incorporated into preexisting neural circuitry and become fully functioning neurons. In the mammalian brain, adult neurogenesis occurs within the hippocampus, a brain region known to be important in learning and memory. In rats, successful acquisition of certain learning tasks increased new neuron numbers when the learning was sufficiently challenging (Curlik and Shors, 2011). It has also been demonstrated that a spatial discrimination task requires new neurons when the discrimination is more …

Advancing The Assessment And Treatment Of Signs And Symptoms Of Parkinson Disease, David Scott May

WUSM Theses and Dissertations – All Programs

People with PD often report signs and symptoms that negatively impact quality of life. Among these are balance difficulties, impaired gait, and FOG. New treatment and assessment strategies for these signs and symptoms are needed, as current techniques are limited. While new treatment and assessment strategies continue to emerge, gaps in knowledge persist. Deep brain stimulation (DBS) has been utilized in many people with PD throughout the 21st century, but it is unknown specifically how subthalamic nucleus deep brain stimulation (STN-DBS) affects balance. Alternative treatment strategies, such as a dental mouthpiece, have also been proposed. While dental mouthpieces have shown …

Cognitive Testing For Sport Concussion: The Immediate Post-Concussion Assessment And Cognitive Testing (Impact), Julia E. Maietta

UNLV Theses, Dissertations, Professional Papers, and Capstones

Sport concussion is among the most common injuries for an athlete to experience during sport participation. Because of the complex pathophysiological process that affects the brain during and after concussion, symptoms can be heterogeneous in presence and severity. Although most acute symptoms (e.g., headache, slowed processing speed, loss of consciousness, irritability, depression, anxiety) resolve within seven to 10 days for most athletes, there is evidence that higher initial symptom burden and other genetically based differences can lead to longer symptom duration and complicated recovery post-concussion. Because structural changes that commonly occur as a result of concussion (e.g., diffuse axonal injury) …

Reelin Supplementation For The Rescue Of Fragile X Syndrome., Nicole K. Morrill

USF Tampa Graduate Theses and Dissertations

Reelin is a large, extracellular matrix glycoprotein involved in neuronal migration during embryonic brain development and synaptic plasticity in the adult brain. Reelin consists of eight EGF-like repeats and undergoes natural cleavage at two sites, between repeats 2 and 3 and repeats 5 and 6, resulting in five naturally occurring fragments. The role of Reelin in the developing central nervous system has been extensively characterized, and loss of Reelin or disruption in the signaling cascade may contribute to the cognitive impairments seen in numerous neurodevelopmental or aging diseases such as schizophrenia, autism, depression, epilepsy, and Alzheimer’s disease. Reelin’s signaling potentiates …

The Impact Of Single Nucleotide Polymorphisms On Cortisol Receptor Activity In Populations With Obesity, Cassidy Michalicka

Honors Theses

Cortisol is a crucial part of the endocrine system; it has the capacity to affect nearly every organ and tissue in the human body. When functioning correctly, cortisol is known to regulate the body’s stress response, control metabolism, suppress inflammation, regulate blood pressure, regulate blood sugar, regulate our body’s circadian rhythm, and much more. When the concentration of cortisol in the blood is elevated for an excessive period, the body responds with symptoms such as hyperglycemia, hypertension, weight gain, and moon face. Commonly this is known as Cushing’s Syndrome (CS), and interestingly, we have seen a phenotypic resemblance when contrasted …

Real-Time Fmri Neurofeedback And Ptsd: Efficacy In Symptom Relief And Neural Circuit Restoration, Sophia F. Ryker

University Honors Theses

Background: Posttraumatic stress disorder (PTSD) is recognized by the DSM-V as resulting from exposure to a traumatic event and the subsequent, prolonged experience of intrusive symptoms, avoidance behavior, altered cognitive functioning and hyperarousal. Current treatments often do not provide relief from symptoms and there is a need for neuro-scientifically informed interventions.

Methods: Through the review of all available studies using real-time fMRI neurofeedback (rt-fMRI-NF) as a treatment for PTSD, the efficacy of this therapeutic intervention was analyzed in order to make specific recommendations for the neurofeedback protocols of future studies.

Results: Evidence demonstrated successful reduction in symptom severity and normalizing …

On The Roles Of Trait Anxiety And Toll Like Receptor 4 In Amphetamine Sensitization In Adolescent Male Rats, Corey A. Calhoun

Graduate Doctoral Dissertations

Mammalian adolescence can be a difficult transition from childhood to adulthood, where increases in impulsivity and novelty- and risk-seeking are combined with heightened affect and elevated sensitivity to stress. Indeed, during adolescence, first drug use patterns emerge and in the continental United States, increasing misuse of amphetamines has been observed in adolescent youth. Myriad neural mechanisms underlie this shift in adolescence, including the dynamic remodeling of the mesocorticolimbic (MCL) pathway. Repeated drug administration affects neuroimmune substrates within the MCL circuit including toll-like receptor 4 (TLR4)Advances in addiction neuroscience indicate that drugs of abuse activate neural TLR4 and implicate glial TLR4 …

Salience Coding In The Basal Forebrain And The Heterogeneous Underpinnings Underlying Novelty Computations, Kaining Zhang

McKelvey School of Engineering Theses & Dissertations

Humans and animals are consistently learning from the environment by interacting with it and getting feedback from their actions. In the environment, some objects are more important than others, because they are associated with reward, uncertainty, surprise, or novelty etc. These objects are salient to the animal. Salient objects attract attention and orientation, increase arousal, facilitate learning and memory, and affect reinforcement learning and credit assignment. However, the neural basis to support these effects is still not fully understood.We first studied how the basal forebrain, one of the principal sources of modulation of the neocortex, encodes salience events. We found …

Defining The Role Of Rare Genetic Variants That Drive Risk And Pathogenesis Of Alzheimer’S Disease, Matthew James Rosene

Arts & Sciences Electronic Theses and Dissertations

Alzheimer’s disease (AD) is the leading cause of dementia and is pathologically defined by the aggregation of extracellular amyloid plaques and intracellular neurofibrillary tangles. Rare heritable mutations within the genes for amyloid precursor protein (APP) and presenilin 1 (PSEN1), and presenilin 2 (PSEN2) cause early onset AD and account for approximately 1% of AD cases. While the majority of AD cases are late-onset (LOAD), which is defined by a markedly more complex genetic architecture that is comprised of many genetic risk factors that influence AD through multiple cellular pathways. The advent of deep sequencing analyses have allowed for the identification …

Functional And Anatomical Characterization Of Descending Periaqueductal Gray (Pag) Projections And Their Role In Pain Modulation, Jose Gabriel Grajales

Arts & Sciences Electronic Theses and Dissertations

Endogenous analgesic pathways embody a potential target for the development for chronic pain therapies. Previous studies have demonstrated the role of the ventrolateral periaqueductal gray (vlPAG) in descending pain modulation. It has been proposed that tonic GABAergic neurotransmission at the level of the vlPAG serves to inhibit efferent excitatory projections that mediate descending analgesia. Disinhibition of these projection neurons allows subsequent activation of rostral ventromedial medulla (RVM) neurons that inhibit nociception at the level of the spinal cord. However, lack of cell-type specificity in these studies has prevented the determination of the role of specific subsets of vlPAG neurons in …

Validation, Categorizing, And Prediction Of Upper Limb Outcomes After Stroke, Jessica Barth

Arts & Sciences Electronic Theses and Dissertations

The incidence and costs of stroke in the United States are projected to rise over the next decade because of the aging population. Declining stroke mortality over the past few decades means that more people survive stroke and live with physical, cognitive, and emotional disability. Stroke remains one of the leading causes of disability in the United States because very few survivors experience a full recovery of their upper limb. Upper limb recovery after stroke is critical to performing activities of daily living and physical and occupational therapies are one of the only treatment options to address these challenges. The …

Understanding The Influence Of Individual-Level Sources Of Pathology Variation On Neuroimaging Measures Of Alzheimer Disease, Austin Andrew Mccullough

Arts & Sciences Electronic Theses and Dissertations

The overall goal of this dissertation is to gain a better understanding of how current Alzheimer disease pathologic progression models interact with sources of individual-level variation in pathology to influence overall disease progression in a clinically meaningful way. Many sources of variation, both internal (e.g., genetic mutations, heterogeneity of tau pathology) and external (e.g., diet and exercise, sleep quality), are known to influence disease progression and symptom onset in AD. With the advent of therapies that have shown successful reduction of amyloid load in trials and the rapid progression of anti-tau therapies, we hypothesize that a better understanding of how …

Disuse-Driven Plasticity In The Human Brain, Dillan James Newbold

Arts & Sciences Electronic Theses and Dissertations

Brain circuits are shaped and maintained by active use. We blocked use of motor circuits in three adult participants by constraining the dominant upper extremity in a cast for two weeks, causing loss of strength and fine motor function. Daily resting-state functional magnetic resonance imaging (rs-fMRI) collected for 42-64 days before, during and after casting revealed two sets of changes in brain function. First, large, spontaneous pulses of activity occurred in the disused motor circuits. Pulses showed a consistent pattern of propagation through the disused circuits— occurring earliest in the dorsal anterior cingulate cortex (dACC) and supplementary motor area (SMA), …

Vcp: A Gatekeeper For Intracellular Proteopathic Seeding, Jiang Zhu

Arts & Sciences Electronic Theses and Dissertations

Protein inclusions such as β-amyloid, tau, α-synuclein, and TDP-43 are considered the pathologic hallmarks of many neurodegenerative diseases. These proteins are prone to misfold, aggregate, and template new aggregates. Accumulating evidence suggests that those proteins in their high-molecular-weight forms can serve as a "seed", spread through an interconnected brain network, and induce new inclusions. Therefore, it is essential to understand the mechanism of proteopathic seeding. In this dissertation, we performed a whole genomic CRISPR-Cas9 KO screening to identify gene modifiers of αS seeding. Within the screening, we found several hits of endolysosomal function and trafficking, including VCP. VCP is a …

A Preliminary Investigation Of Neuroantibody Levels, Prevalence, And Environmental Factors In Patients With Neurological Dysfunction, Jihan Azar

Theses and Dissertations

Nervous system damage comprises a large proportion of diseases worldwide. It is also the most difficult to diagnose. Biomarkers for nervous system damage are needed in order to diagnose these diseases early enough to allow for intervention. In this study, we recruited patients from two Egyptian hospitals with MCI, ET and NMS and health references. Serum autoantibody levels against neural proteins and heavy metals were analyzed and compared. Immunoglobulin G (IgG) antibodies against neurofilament H (NFH), Glial Fibrillary Acidic Protein (GFAP), Myelin Basic Protein (MBP) and alpha synuclein (a-SYN) and Immunoglobulin M (IgM) antibody against neurofilament light (NFL) were among …