Neuroscience and Neurobiology Commons^™

Circadian Regulation Of The Timing Of Pre-Ovulatory Luteinizing Hormone Surge In Mice And Hamsters, Ajay Kumar

Doctoral Dissertations

Endogenous daily (circadian) oscillators ensure the proper timing of physiological and behavioral processes that are essential to health. A set of core clock genes and their protein products function in transcriptional/translational feedback loops (TTFLs) that time and coordinate vital homeostatic, cognitive, and hormonal processes. A master pacemaker in the suprachiasmatic nucleus (SCN) coordinates circadian function throughout the organism. Investigating the causal role of genetically defined cell types in the suprachiasmatic nucleus for circadian rhythms is essential to understand how an animal’s physiology is temporally organized. This thesis explores the role of molecular clocks within particular cell types in regulating physiology. …

Neurocounseling And The Counseling Profession: Integrating Neuroscience Into The Practice Of Counseling, Sherri Clark

Dissertations, Theses, and Projects

Neurocounseling integrates Neuroscience into mental health counseling by using psychoeducation, teaching, and illustrations as well as other forms of therapy (CBT, Interpersonal Psychotherapy, Narrative Therapy, etc.) to assist clients in understanding the neurological basis of many mental and behavioral health concerns. Clients can benefit from Neurocounseling as they gain a more comprehensive understanding of the central nervous system and brain function in connection to the body, cognition, mood, and behaviors, also known as the mind and body connection. Neuroplasticity and neurogenesis allow us to understand the brain’s amazing capability to grow and change. Understanding neuroscience allows for more integrated case …

The Subplate And Its Role In The Gaba System In The Prefrontal Cortex, Gaeul Kyla Lee

Electronic Thesis and Dissertation Repository

During early brain development, the subplate relays thalamocortical afferents. Lesions to the subplate have been implicated in developmental abnormalities of cortical GABAergic circuits. This thesis examined the effects of subplate lesions in the prefrontal cortex of rats on the expression of GABA markers (parvalbumin and GAD67) and GABA synapse maturation [potassium-chloride cotransporter (KCC2) and sodium-potassium- chloride cotransporter (NKCC1)] with relevance to the characterization of a rat model for schizophrenia. Lesions were made on postnatal day 1 (P1). Lesioned and control rats were sacrificed between P5 and P90 and immunolabelled for parvalbumin, GAD67, KCC2, and NKCC1. We found decreased parvalbumin expression …

Restorative Potential And Working Memory Capacity Of Exposure To Vegetation In Indoor Built Environments, Jee Heon Rhee

Theses and Dissertations

This research seeks to understand how natural elements – specifically, vegetation in the indoor environment - influence people’s ability to restore attention and working memory capacity. Previous research demonstrates the benefits of nature on human beings in various ways. For instance, numerous studies show the positive effects of nature on stress reduction (Hartig, Mang, & Evans, 1991; Ulrich et al., 1991) and attention restoration (Staats, Kieviet, & Hartig, 2003). However, most of these studies focus on the effect of nature in outdoor settings. Relatively few studies focus on the presence of natural elements indoors. This is an important gap in …

Implementation Of A Guideline For Major Depressive Disorder In A Private Practice Clinic, Doreen Phillips

Doctor of Nursing Practice

Major depressive disorder (MDD) is a chief mental health illness that carries a profound economic burden. Many who suffer from MDD find little to no relief with traditional pharmacological interventions.The 2010 American Psychiatric Association Guidelines for Treatment of Patients with MDD recognized TMS as a second-line treatment choice. Several double-blind, randomized controlled trials illustrated the efficacy and safety of TMS as a viable treatment option for MDD. The purpose of this project was to implement standardized processes through the use of a treatment guideline to help provide comprehensive treatment options for patients suffering from moderate to severe major depressive disorder …

Qki-Mediated Cholesterol Biosynthesis In Eye Lens And Myelin Of The Central Nervous System, Seula Shin, Seula Shin

Dissertations & Theses (Open Access)

Cells obtain cholesterol in two ways, de novo biosynthesis and uptake from circulation. While most tissues utilize both sources, eye lens and brain depend extensively on cholesterol biosynthesis due to the limited supply from circulation. Lens cell membrane consists of highest portion of cholesterol. Brain is the most cholesterol-rich organ, which accounts for 23% of total cholesterol. Genetic mutations of cholesterol biosynthesis enzymes in humans and animal models present cataracts and hypomyelinating disorders linked to neurological impairment. Yet, it remains unclear how gene expression of cholesterol biosynthesis is regulated in lens and brain. Therefore, studying cholesterol biosynthesis in both tissues …

Inactivation Of Nucleus Reuniens Impairs Spatial Memory In Mice, Miranda Schwabe

Theses and Dissertations

Episodic memory is a complex process requiring input from several regions of the brain. Coordinated activity in the Dorsal Hippocampus (DH) and medial Prefrontal Cortex (mPFC) is required for episodic memory consolidation. Our laboratory demonstrated that simultaneous subthreshold chemogenetic inactivation of the dorsal hippocampus (DH) and medial prefrontal cortex (mPFC) impairs the consolidation of object placement (OP) and object recognition (OR) memory in female mice (Tuscher et al., 2018), suggesting that these two brain regions work in concert to promote memory consolidation. However, the mechanisms through which the DH and mPFC interact to promote memory consolidation remain poorly understood. A …

The Role Of Cerebellar Structural Plasticity And Astrocytic Activity In Motor-Skill Learning, Morgan Stevenson

Theses and Dissertations

Motor-skill learning is associated with cerebellar synaptogenesis and astrocytic hypertrophy, but most of these assessments of cerebellar ultrastructure have been completed after one month of training. After one month of training, the motor-skills necessary to complete these tasks have been acquired for weeks. Furthermore, the contributions of cerebellar astrocytes to motor-skill learning remains largely unexamined. The first experiment of this dissertation aimed to characterize cerebellar ultrastructure during the acquisition phase of motor-skill learning, at a point when motor performance is still improving. The second experiment aimed to examine the contributions of cerebellar astrocytes to motor-skill learning by activating astrocytic Gi-signaling …

Data-Driven Approach To Dynamic Resting State Functional Connectivity In Post-Traumatic Stress Disorder, Carissa Weis

Theses and Dissertations

Posttraumatic stress disorder (PTSD) is a heterogenous psychological disorder that may result from exposure to a traumatic event. Using functional magnetic resonance imaging (fMRI), symptoms of PTSD have been associated with aberrations in brain networks that emerge in the absence of a given cognitive demand or task, called resting state networks. Most previous research in resting state networks and PTSD has focused on aberrations in the static functional connectivity among specific regions of interest (ROI) in the brain and within canonical networks constrained by a priori hypotheses. However, dynamic fMRI, an approach that examines changes in brain network characteristics over …

Reversal Of Neurodegeneration By Engineered Monocytes In Alzheimer’S Disease, Chao-Hsien Chen

Dissertations & Theses (Open Access)

The health challenges posed by Alzheimer’s disease (AD) continue to grow as societies age worldwide. Accumulation of Tau-associated pathology correlates with clinical cognitive deterioration in AD. Resident myeloid cells within the central nervous system (CNS) have a limited capacity to uptake and degrade Tau; however, the resulting secretion of proinflammatory cytokines only acts to accelerate neurodegeneration. Therapeutic antibodies can reduce the neurotoxic oligomeric form of Tau (o-Tau), but in doing so they also aggravate inflammation. Attenuating mutation of the antibody Fc region can silence inflammation but also eliminates its capacity to mediate o-Tau clearance by CNS myeloid cells. Thus, there …

Calcium Dyshomeostasis In Neurodegeneration, Nicholas Emanuel Karagas

Dissertations & Theses (Open Access)

Neurodegenerative diseases, despite constituting a major and growing cause of mortality globally, have few effective treatments. In order to develop novel therapeutics to combat neurodegeneration, a better understanding of the molecular mechanisms underlying these diseases is needed. Neurons rely on Ca²⁺ to mediate many of their unique functions, and aberrant Ca²⁺ signaling has been broadly implicated in neurodegeneration. The goal of this dissertation is to delineate specific examples of Ca²⁺ dyshomeostasis that I have uncovered in Drosophila models of neurodegeneration.

I first define the role a neurodegeneration-associated mutation plays in perturbing presynaptic [Ca²⁺], which is …

Qki-Mediated Cholesterol Biosynthesis In Eye Lens And Myelin Of The Central Nervous System, Seula Shin, Seula Shin

Dissertations & Theses (Open Access)

Cells obtain cholesterol in two ways, de novo biosynthesis and uptake from circulation. While most tissues utilize both sources, eye lens and brain depend extensively on cholesterol biosynthesis due to the limited supply from circulation. Lens cell membrane consists of highest portion of cholesterol. Brain is the most cholesterol-rich organ, which accounts for 23% of total cholesterol. Genetic mutations of cholesterol biosynthesis enzymes in humans and animal models present cataracts and hypomyelinating disorders linked to neurological impairment. Yet, it remains unclear how gene expression of cholesterol biosynthesis is regulated in lens and brain. Therefore, studying cholesterol biosynthesis in both tissues …

Association Between White Matter Hyperintensities, Cortical Thinning, And Clinical Outcomes In Mild Traumatic Brain Injury, Thomas Helmut Knoblauch

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traumatic Brain Injury (TBI) is a global health challenge, with over 4.6 million confirmed cases annually in North America alone. Mild traumatic brain injuries (mTBIs) are the most common and make up approximately 81% of all TBI diagnoses worldwide [1]. Studies indicate that 10–15% of patients suffer from trauma induced symptoms (i.e. headache, loss of balance, cognitive impairments, fatigue, and mental health/affective disorders) as far as 1 year post injury [2]. Prediction and management of these post-traumatic sequalae is complicated by a lack of symptom associated neuroimaging findings. In spite of a “prominent distribution” of frontotemporal WMHs in pediatric subjects …

Examining The Structure Of Symbolic Number Representations In The Parietal Cortex: An Rsa Study, Aymee Alvarez Rivero

Electronic Thesis and Dissertation Repository

Previous studies using fMRI adaptation to investigate the neural substrate of symbolic number processing have found ratio-dependent responses in regions of the parietal cortex, suggesting that number symbols are coded by overlapping neuronal populations: the larger the ratio between two numerals, the more their representation overlap. The current study analyzed the distributed patterns of activation associated with numerals presented during this task. I could not find substantial evidence supporting the ratio-dependent structure of the similarity space predicted by the univariate adaptation analyses. I also failed to find evidence in favor of the alternative model that similarities were driven by lexical …

Sexually Dimorphic Oxytocin Receptor-Expressing Neurons In The Anteroventral Periventricular Nucleus Regulates Maternal Behavior, Kaustubh Sharma

LSU Doctoral Dissertations

The neurohypophysial hormone oxytocin is involved in the regulation of social behaviors, including social recognition, pair bonding, and sex-specific parental behaviors in a variety of species. Oxytocin triggers these social behaviors by binding to oxytocin receptors (OXTR) in various parts of the brain. Oxytocin-induced sex-typical behavior, therefore, suggests a sexual dimorphic distribution of OXTR in the brain. In recent years, the oxytocin system in the brain received tremendous attention as a potential pharmacological target for treatment of many psychiatric disorders, such as anxiety, autism spectrum disorders, and even sex-specific psychiatric disorder like postpartum depression (PPD). An important problem and a …

Elucidating The Consequence And Cause Of Microrna Dysregulation In Amyotrophic Lateral Sclerosis (Als), Zachary C. E. Hawley

Electronic Thesis and Dissertation Repository

Amyotrophic Lateral Sclerosis (ALS) is a progressive motor neurodegenerative disorder with an average life expectancy of 2-5 years post-diagnosis. Common pathological features associated with ALS are the formation of cytoplasmic inclusions of intermediate filaments and RNA-binding proteins within motor neurons. The formation of intermediate filament cytoplasmic inclusions is believed to be driven by a loss of stochiometric expression between five neuronal intermediate filament proteins—NFL, NFM, NFH, INA and PRPH—where there is a selective suppression of the steady-state levels of NEFL, INA and PRPH mRNA. Further, three RNA-binding proteins—TDP-43, FUS and RGNEF—have been shown to co-aggregate with each other in …

Computational Unfolding Of The Human Hippocampus, Jordan M. K. Dekraker

Electronic Thesis and Dissertation Repository

The hippocampal subfields are defined by their unique cytoarchitectures, which many recent studies have tried to map to human in-vivo MRI because of their promise to further our understanding of hippocampal function, or its dysfunction in disease. However, recent anatomical literature has highlighted broad inter-individual variability in hippocampal morphology and subfield locations, much of which can be attributed to different folding configurations within hippocampal (or archicortical) tissue. Inspired in part by analogous surface-based neocortical analysis methods, the current thesis aimed to develop a standardized coordinate framework, or surface-based method, that respects the topology of all hippocampal folding configurations. I developed …

Cognitive Resources Are Recruited Consistently Across People During Story Listening, Matthew T. Bain

Electronic Thesis and Dissertation Repository

Degraded speech encoding as a result of hearing loss increases cognitive load and makes listening effortful. Standard hearing assessment does not capture this cognitive impact of hearing impairment. Speech-in-noise testing measures intelligibility for isolated sentences that are typically not engaging and lack meaningful context. These materials may not capture the processes involved in everyday listening situations, in which people are often intrinsically motivated to comprehend the speech they are hearing. The current study explored a novel approach using natural, spoken stories. We first characterized time courses of executive load during story listening in young individuals with normal hearing using a …

Investigating Cognitive Impairment In Tdp-43 Mouse Models Of Ftd-Als Using Automated Touchscreens, Keon Coleman

Electronic Thesis and Dissertation Repository

TAR-DNA-binding protein 43 (TDP-43) misfolding and aggregation is a major pathological hallmark of frontotemporal dementia-amyotrophic lateral sclerosis (FTD/ALS). FTD/ALS is characterized by motor and cognitive impairment, with cognitive impairment frequently reported before the onset of classical motor symptoms. Yet, treatment for cognitive decline in FTD/ALS is lacking, and robust cognitive phenotypes related to TDP-43 proteinopathy have not been established for most mouse models of FTD/ALS. Herein, we used automated touchscreen technology to assess executive function (affected in FTD/ALS) in male TDP-43^Q331Klow and ^-G348C FTD/ALS transgenic mice. The touchscreen pairwise visual discrimination task revealed impairments in 4-5-month-old TDP-43^Q331Klow and …

Aci-35 And Aadvac1 Active Immunotherapy As Preventative Treatment Options For Chronic Traumatic Encephalopathy, Emily C. Boehlein

Selected Honors Theses

One of the most common, as well as one of the most dangerous injuries amongst athletes today is mild traumatic brain injury (mTBI), commonly known as concussion. Aside from physical symptoms such as nausea, dizziness, and headaches; concussions have can have longterm effects on brain physiology. A common neurological disease that can result from multiple concussions is Chronic Traumatic Encephalopathy (CTE), characterized by symptoms such as severe depression, anxiety, confusion, and aggression; amongst others.1 On the cellular level, CTE is classified by a unique pathway that leads to the hyperphosphorylation of tau protein and subsequent clumping of tau-containing neurofibrillary tangles …

Dnajc7, A Molecular Chaperone Protein That Modulates Protein Misfolding In Amyotrophic Lateral Sclerosis (Als), Meaghan Kathleen Stoltz

Electronic Thesis and Dissertation Repository

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease associated with protein misfolding and dysregulated cellular protein quality control mechanisms. Molecular chaperones, and heat shock proteins (Hsp), are key players in maintaining cellular protein quality control. DNAJC7 is an understudied cytosolic Hsp40 that works together with Hsp70 and Hsp90 to regulate proper protein folding or degradation. Of note, mutations in the gene encoding DNAJC7 were discovered to cause familial ALS. We asked whether ALS-associated mutations in DNAJC7 compromise its function as a chaperone, which may cause the toxic accumulation of misfolded proteins. This study attempts to uncover the functions of DNAJC7 …

Degradation Of Transcriptional Repressor Atf4 During Late-Phase Long-Term Potentiation, Spencer Smith

Biology Theses

Maintenance of long-term synaptic plasticity requires gene expression mediated by cAMP-responsive element binding protein (CREB). Gene expression driven by CREB can commence only if the inhibition by a transcriptional repressor ATF4 (activating transcription factor 4; aka CREB2) is relieved. Previous research showed that the removal of ATF4 occurs through ubiquitin-proteasome-mediated proteolysis. Using chemically induced hippocampal long-term potentiation (cLTP) as a model system, we investigated the mechanisms that control ATF4 degradation. We observed that ATF4 phosphorylated at Serine-219 increases upon induction of cLTP and decreases by about 30 min thereafter. Proteasome inhibitor β-lactone prevents the decrease in ATF4. We found that …

Optimizing Preprocessing Of Fmri Data To Maximize Correspondence Of Functional Anatomy Across Individuals, Nargess Ghazaleh

Electronic Thesis and Dissertation Repository

In movie-activation fMRI, intersubject correlation (ISC) indicates a functional correspondence across viewers. Brains di↵er in shape; spatial normalization and smoothing enhance inter-subject functional overlap. We compare three normalization methods and six smoothing levels to discover which method yields the best functional overlap, indexed by ISC. This is key to optimizing data analysis in clinical studies using movie-activation fMRI in future. In a 3T scanner, 44 healthy subjects watched an 8-min movie. Both normalization and smoothing a↵ected the strength and extent of the ISC. ISC values were more robust for ANTs and DARTELthanforSPM12andwere(asymptotically)thestrongestat12mmsmoothing. When image data are preprocessed with high-dimensional volumetric …

The Cognitive Thalamus: Source Analysis Of Scene Working Memory Delay Activity, Bernard A. Gomes

Dissertations, Theses, and Capstone Projects

Working Memory represents a limited-capacity store for maintaining information and manipulating the store's contents over a short period for the guidance of goal-directed behavior. Working Memory is an essential component of executive functions that are intricately associated with the prefrontal cortex (PFC). The PFC has been implicated in maintaining task-related information online for brief periods in the absence of relevant information. This active maintenance phase is called the delay period that occurs between encoding and retrieval of the stimulus. Previous studies have attempted to understand the relationship between working memory and the PFC, especially during the delay or maintenance phase …

Shared Neural Substrates Of Perception And Memory: Testing The Assumptions And Predictions Of The Representational-Hierarchical Account, D. Merika W. Sanders

Doctoral Dissertations

Proponents of the representational-hierarchical (R-H) account claim that memory and perception rely on shared neural representations. In the ventral visual stream, posterior brain areas are assumed to represent simple information (e.g. low-level image properties), but the complexity of representations increases toward more anterior areas, such as inferior temporal cortex (e.g., object-parts, objects), extending into the medial temporal lobe (MTL; e.g. scenes). This view predicts that brain structures along this continuum serve both memory and perception; a structure’s engagement is determined by the representational demands of a task, rather than the cognitive process putatively involved. In a neuroimaging study, I searched …

Analysis Of Newspaper Coverage Of Psilocybin From January 1, 1989 To December 31, 2019, Dax Oliver

Dissertations, Theses, and Capstone Projects

Psilocybin is a chemical compound that has received a lot of attention from medical researchers in recent years. However, this research is not merely a medical issue but a social and political one as well. In the 1960s, psilocybin and other psychedelic compounds were widely ingested outside of clinical settings. This alarmed some of the American public, resulting in severe legal restrictions on psilocybin use and research.

Today, many psilocybin advocates hope that it will avoid the negative public sentiment of the 1960s. To help gauge public sentiment about other psychoactive compounds, some studies have examined newspaper coverage, but there …

The Temporal Dynamics Of Ensemble Perception, Michael L. Epstein

Dissertations, Theses, and Capstone Projects

The striking disparity between the subjective richness of experience and the considerable limitations of perceptual processing has emerged as an essential, enduring question in both vision science and philosophy of mind. A potential solution to this issue is ensemble perception: the ability for the visual system to compute the statistical summaries of object groups, effectively compressing an otherwise overwhelming amount of information. Previous work has supported that ensemble statistics can be perceived quickly and accurately for a wide range of object features. This has motivated models of ensemble perception as an early process in vision, providing an initial sense of …

Investigating The Neural Mechanisms Of Unconscious And Illusory Touch Perception, Lua Koenig

Dissertations, Theses, and Capstone Projects

Despite our everyday reliance on touch, from manipulating tools to dressing ourselves, relatively little is known about the neural correlates of tactile perception. As with other modalities, our conscious, reportable experiences of touch can dissociate from the physical tactile stimulation processed by the skin. In unconscious touch perception, tactile stimuli can be processed and guide our behavior without an accompanying conscious percept. For example, we may swat away a mosquito without having consciously registered its presence on our skin. In tactile illusions, conscious tactile experiences occur without a corresponding tactile stimulus. Multisensory tactile illusions arise when stimulation of a different …

Functions Of Fibroblast Growth Factor Homologous Factor 2 In Excitable Tissues, Christopher Marra

Dissertations, Theses, and Capstone Projects

Purpose: Fibroblast Growth Factor Homologous Factors (FHFs) are a group of proteins known to associate with and modulate voltage-gated sodium channels (Na_v) in excitable cells. The four FHF genes are differentially expressed in specific cell-types, with FHF2 expressed prominently in the hippocampus, cerebral cortex, heart and dorsal root ganglia. Due to previous unavailability of an Fhf2 knockout mouse, this gene’s functions have been understudied in comparison to other those encoding other FHFs. The purpose of this research has been to better understand the normal physiological functions of FHF2 at the cellular and system levels in the heart, sensory …

Rehabilitative Movement Approaches And Dance Interventions In Parkinson’S Disease, Cecilia Fontanesi

Dissertations, Theses, and Capstone Projects

The scope of this work is to address the functional deficits and symptoms experienced by those living with Parkinson’s Disease through movement interventions.

Chapter 1 offers a brief overview of current pharmacotherapy and rehabilitation approaches in Parkinson’s, focusing on dance in particular as a movement intervention that may be particularly suited to this population.

Chapter 2 focuses on brain plasticity and motor learning in PD, reporting the effects of rTMS applied after the acquisition of a motor skill. In this study, adaptation tested in patients with PD was comparable in the sham and TMS sessions, while retention indices tested on …