Neuroscience and Neurobiology Commons^™

Metabolic Control Of Proliferation And Differentiation In Oligodendrocytes, Sami Sauma

Dissertations, Theses, and Capstone Projects

Oligodendrocytes (OLs) are specialized cells whose membrane extension, called myelin, wraps the axons providing insulation, trophic and metabolic support, and is essential for proper functioning of the central nervous system. Inappropriate myelin formation, damage or dysfunction of oligodendrocytes has been identified in several neurological disorders and often precedes the loss of neuronal cells. OLs derive from proliferating oligodendrocyte progenitor cells (OPCs), which exit from the cell cycle and undergo a series of transcriptional and epigenetic events, including histone post-translational modifications, resulting in morphological and functional changes. Our lab previously identified elevated levels of histone acetylation in proliferating OPCs during the …

Examining Metacognitive Access To Low-Level Ensemble Representations, Vladimir Mudragel

Dissertations, Theses, and Capstone Projects

Ensemble perception is a process that allows our sensory systems to rapidly extract summary information about the stimuli in the environment. For example, we are able to get a sense of the average number of items in a group of similar items (Burr & Ross, 2008; Halberda, Sires, & Feigenson, 2006) or the average size of a group of similar shapes of different sizes (Ariely, 2001). It is theorized that the qualitative result of ensemble perception is that it provides a gist impression of the current environment, which then enables attentional processes in the brain to determine which parts of …

A Novel Therapeutic Strategy For Alzheimer’S Disease: Sex-Dependent Mechanisms Altered By The Hdac Inhibitor Rg2833 In A Transgenic Rat Model, Kelechi Ndukwe

Dissertations, Theses, and Capstone Projects

Alzheimer’s disease (AD) is the most common cause of dementia. In the United States, AD affects about 6.2 million Americans and is projected to reach 13.8 million by 2050. Currently, there are no effective therapies for AD and therapies targeting epigenetic mechanisms have shown to be effective in improving cognitive performance in animal models of AD. However, until now no study has reported sex-dependent mechanisms leading to differential expression of genes that contribute to changes in AD pathology. From our in silico studies, we identified an FDA-approved drug, RG2833 (N-[6-(2-aminoanilino)-6-oxohexyl]-4-methylbenzamide) that penetrates the blood brain barrier and can potentially ameliorate …

Electrophysiological Signatures Of Stress Adaptability In The Bnst-Vta Pathway, Yuka Miura

Dissertations, Theses, and Capstone Projects

Chronic stress has detrimental effects on psychological and physiological health. Incapability to adapt to chronic stress can lead to depression, anxiety disorders, and addiction. The brain regions critical for reward processing share diverse physiological and molecular changes linked to depressive-like behaviors as a result of chronic stress. Cumulative evidence shows that counteraction or prevention of these alterations in neurons, occasionally in a projection-specific manner, can enhance stress adaptation or resilience.

Chronic stress induces various changes in the brain, including in the bed nucleus of the stria terminalis (BNST) and the ventral tegmental area (VTA). The neural projections from the BNST …

Automatic Analysis Of The Frequency, Vigor, And Complexity Of Spontaneous Locomotion Bouts Of Mice With Loss And Gain Of Function Of The G Protein-Coupled Receptor Smoothened In Cholinergic Neurons, Aleksandra Feshchenko

Dissertations, Theses, and Capstone Projects

Locomotion, a fundamental behavior, is classically assessed using simple metrics of velocity and total distance moved in an open field. This behavior however offers rich data about the organization and breadth of actions an animal can take while only facing limitations due to the bio-mechanical constraints of the organism. Importantly, these actions are not biased towards a particular task-solution space imposed by many behavioral paradigms. Here, to analyze motor complexity in freely ambulating mice, we developed a method for the automatic and unbiased identification of locomotor bouts which we call Bout Finder (BF). This analysis utilizes Open Feld data to …

You Hurt My Feelings: Autonomic And Behavioral Responses To Social Exclusion And The Moderating Effect Of Psychopathic Traits, Liat Kofler

Dissertations, Theses, and Capstone Projects

Humans have a fundamental need to form and maintain social connections, and thus experiencing social exclusion is extremely distressing as it threatens this basic human need. Individuals who are socially excluded often respond aggressively, not only towards their ostracizers but also towards innocent bystanders, with ostracism being implicated in extreme acts of violence such as school shootings. However, individual differences in behavior exist within the context of social exclusion as not everyone responds aggressively after being ostracized. Identifying risk factors for retaliatory aggressive behavior following experiences of social exclusion may facilitate the development of targeted interventions aimed at mitigating such …

Changes In The Epigenetic Landscape Of Oligodendrocyte Progenitor Cells With Time, David K. Dansu

Dissertations, Theses, and Capstone Projects

Most neonatal oligodendrocyte progenitors (nOPCs) give rise to myelinating oligodendrocytes during development, while a proportion are retained as proliferative undifferentiated cells in the adult brain (aOPCs). Previous studies have reported distinct properties for those two populations but the molecular mechanisms underlying these intrinsic differences are not well understood. Using RNA-sequencing and unbiased histone proteomics analysis, we identify transcripts and histone marks that are higher in aOPCs than nOPCs. The genome-wide ChIP-sequencing analysis of chromatin from aOPCs compared to nOPCs detects greater occupancy of the H4K8ac mark at loci corresponding to the higher transcript levels of oligodendrocyte-specific transcription factors and lipid …

Brainwaves, Memory, And Reward, Rebecca Mccune

Dissertations, Theses, and Capstone Projects

The development of effective educational curricula for enhancing learning involves the crucial consideration of effort and rewards. In the realm of education, teachers commonly employ rewards as motivational tools. Traditionally, these rewards are given to students as a recognition of their successful performance. However, a thought-provoking idea emerges: What if we were to extend rewards to students not solely based on accurate answers, but also on the effort they invest, even in cases where their actual response might be incorrect? Our study explores the potential impact of this approach on the way information is absorbed and subsequently retained, specifically focusing …

Attenuated Typicality Effect In Category-Based Inferences: Implications For Autism Spectrum Disorder, Janani Rajagopalan

Dissertations, Theses, and Capstone Projects

Individuals diagnosed with Autism Spectrum Disorder (ASD) often encounter challenges in assimilating atypical exemplars into their categorical prototypes, a cognitive hurdle that can impact their interpretative and integrative capacities. Addressing this problem, the present research sought to develop a robust methodological approach to reduce the effect of this disparity. We examined the elements embedded within the category's internal structure, with the intention of experimentally attenuating the pronounced typicality effect, which is often exaggerated in ASD.

Across four experiments, the thesis investigated the cognitive and neural underpinnings that shape the access to the typicality gradient intrinsic to a category's structure. The …

Reviewing Research On Down Syndrome To Then Inform And Create A Children’S Book With A Child Protagonist Who Has Down Syndrome, Trey Williams

Honors Projects

Children's literature continually evolves, requiring a steadfast commitment to align with new insights into various disabilities for genuine and accurate portrayal. This project delves into leveraging research to craft a children's book featuring Bonnie Lynn, a protagonist with Down Syndrome, recognizing the growing presence of individuals with Down Syndrome in today's society and the imperative for empathetic understanding within this community.

Proceedings From The Third Annual Society For Neurosports Conference, Neurosports Editorial Staff

Journal for Sports Neuroscience

Proceedings from the Third Annual Society for NeuroSports Conference

Music Advocacy: The Cognitive Development, Behavioral And Emotional Management, And Academic Success That Music Education Provides Students In Louisiana’S Low Socioeconomic Elementary Schools, Cory D. Dugar

Doctoral Dissertations and Projects

There are many technological curricular activities in math and science classrooms, yet few are found in music classrooms. Although many elementary schools may be benefiting from advocacy for music and technology, many elementary schools in the state of Louisiana have lost funding for music programs. For the Louisiana Department of Education to act as an advocate for music education, there must be a thorough understanding of the benefits of music education. Extensive research is one way to suggest that elementary music classes can raise the cognitive capacity of elementary students and could be the catalyst for ensuring the upcoming generation’s …

Assessing Blood Oxygen Level–Dependent Signal Variability As A Biomarker Of Brain Injury In Sport-Related Concussion, Evan D. Anderson, Tanveer Talukdar, Grace Goodwin, Valentina Di Pietro, Kamal M. Yakoub, Christopher E. Zwilling, David Davies, Antonio Belli, Aron K. Barbey

Center for Brain, Biology, and Behavior: Faculty Publications

Mild traumatic brain injury is a complex neurological disorder of significant concern among athletes who play contact sports. Athletes who sustain sport-related concussion typically undergo physical examination and neurocognitive evaluation to determine injury severity and return-to-play status. However, traumatic disruption to neurometabolic processes can occur with minimal detectable anatomic pathology or neurocognitive alteration, increasing the risk that athletes may be cleared for return-to-play during a vulnerable period and receive a repetitive injury. This underscores the need for sensitive functional neuroimaging methods to detect altered cerebral physiology in concussed athletes. The present study compared the efficacy of Immediate Post-concussion Assessment and …

Self-Supervised Pretraining And Transfer Learning On Fmri Data With Transformers, Sean Paulsen

Dartmouth College Ph.D Dissertations

Transfer learning is a machine learning technique founded on the idea that knowledge acquired by a model during “pretraining” on a source task can be transferred to the learning of a target task. Successful transfer learning can result in improved performance, faster convergence, and reduced demand for data. This technique is particularly desirable for the task of brain decoding in the domain of functional magnetic resonance imaging (fMRI), wherein even the most modern machine learning methods can struggle to decode labelled features of brain images. This challenge is due to the highly complex underlying signal, physical and neurological differences between …

The Directional Effect Of Target Position On Spatial Selective Auditory Attention, Heesung Park

Dissertations, 2020-current

Spatial selective auditory attention plays a crucial role in listening in a mixture of competing speech sounds. Previous neuroimaging studies have reported alpha band neural activity modulated by auditory attention, along with the alpha lateralization corresponding to attentional focus. A greater cortical representation of the attended speech envelope compared to the ignored speech envelope was also found, a phenomenon known as 'neural speech tracking’. However, little is known about the neural activities when attentional focus is directed on speech sounds from behind the listener, even though understanding speech from behind is a common and essential aspect of daily life. The …

Nmda Receptor Inhibition On Rodent Optimal Decision-Making In The Diminishing Returns Task, Seth Foust

Research Psychology Theses

There has been growing interest in using N-methyl-D-aspartate (NMDA) receptor antagonists as treatments for mood disorders, but there is still much to learn about their cognitive effects. Research shows NMDA receptors can affect decision-making, and the antagonist MK-801 has had varying effects in rodents. Specifically, some have reported impairments in working memory while foraging behaviors remained intact, while others have demonstrated changes in choice behavior related to delay or risk in behavior tasks. We investigated the role of NMDA receptors in the specific paradigm of optimal decision-making to further confirm MK-801’s effects and to explore whether inhibiting NMDA receptors alters …

Improving Peripheral Nerve Regeneration Through Rehabilitation And Biomaterial-Based Drug Delivery Strategies, Yunfan Kong

Theses & Dissertations

Peripheral nerve injury (PNI) is a common problem worldwide, with trauma being a common cause. PNI can lead to loss of sensory and motor functions, chronic neuropathic pain, and mental health issues, significantly impacting patients' family life, work, and social situation. Recent studies revealed that beyond the topical injury site at peripheral nerves, PNIs can also induce dysfunctions in the central nervous system (CNS) by causing maladaptive plasticity, which will result in exaggeration and exacerbation of the pathological condition caused by primary injuries. The common therapy strategies for PNI treatment are using sutures, nerve autografts or conduits in cases requiring …

Nanoscale Modeling Of Membrane Systems Under Mechanical Deformation In Traumatic Brain Injury Using Molecular Dynamics, Anh Thi Ngoc Vo

Theses and Dissertations

Neuronal membrane disruption and mechanoporation are nanoscale damage mechanisms that critically affect brain cell viability during traumatic brain injury (TBI). These nanoscale cellular impairments are elusive in experiments and necessitate in silico approaches such as molecular dynamics (MD) simulations. Implementing MD, this research aims to investigate the effects of different key factors related to membrane deformation and damage, including force field resolutions, lipid compositions, and loading conditions.

To examine the impact of force field resolution, MD deformation simulations were conducted on 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC) lipid bilayer membranes, using all-atom (AA), united-atom (UA), and coarse-grained Martini (CG-M) force fields. The mechanical responses …

The Importance Of Contrast Sensitivity, Color Vision, And Electrophysiological Testing In Clinical And Occupational Settings, Frances Silva

Theses & Dissertations

Visual acuity (VA) is universally accepted as the gold standard metric for ocular vision and function. Contrast sensitivity (CS), color vision, and electrophysiological testing for clinical and occupational settings are warranted despite being deemed ancillary and minimally utilized by clinicians. These assessments provide essential information to subjectively and objectively quantify and obtain optimal functional vision. They are useful for baseline data and monitoring hereditary and progressive ocular conditions and cognitive function. The studies in this dissertation highlight the value of contrast sensitivity, color vision, and cone specific electrophysiological testing, as well as the novel metrics obtained with potential practical clinical …

Microglial Response To Glucocorticoids During Chronic Sleep Fragmentation, Christian Chelson

Masters Theses & Specialist Projects

Sleep is one of the body’s greatest and most basic needs. Chronic sleep loss (<6 hours a day) is linked to many cardiovascular issues, diabetes, and inflammatory conditions and has been shown to lower life expectancy. Obstructive sleep apnea (OSA) is a complication that causes sleep fragmentation in >8% of adults from developed countries, and many with OSA may be unaware of their condition. Having long-term OSA is linked to neuroinflammation caused by activated microglia in the brain, but the mechanics of this inflammation are not well understood. It is known that glucocorticoids, steroid hormones produced and released from the adrenal glands, have a suppressive effect on microglia. The purpose of this study is to explore the role that glucocorticoids have upon microglia activation induced by chronic sleep fragmentation (SF). C57BL/6J mice were …

Identification Of Structural Brain Alterations In Adolescents With Depressive Symptomatology, J. Bashford‑Largo, R. James R. Blair, Karina S. Blair, Matthew Dobbertin, Ahria Dominguez, Melissa Hatch, Sahil Bajaj

Center for Brain, Biology, and Behavior: Faculty Publications

Introduction: Depressive symptoms can emerge as early as childhood and may lead to adverse situations in adulthood. Studies have examined structural brain alternations in individuals with depressive symptoms, but findings remain inconclusive. Furthermore, previous studies have focused on adults or used a categorical approach to assess depression. The current study looks to identify grey matter volumes (GMV) that predict depressive symptomatology across a clinically concerning sample of adolescents.

Methods: Structural MRI data were collected from 338 clinically concerning adolescents (mean age = 15.30 SD=2.07; mean IQ = 101.01 SD=12.43; 132 F). Depression symptoms were indexed via the Mood …

Voluntary Action And Conscious Intention, Jake Gavenas

Computational and Data Sciences (PhD) Dissertations

Traditional experimental methodology in neuroscience involves comparing responses to different stimuli to make inferences about the human brain. However, human volition entails making decisions and acting in a manner that is underdetermined by the external environment. Investigations of the neuronal basis of volition have led to new controversies regarding the existence of free will, and offer potential directions for medical treatments of disorders such as addiction, akinetic mutism, and locked-in syndrome. However, because volition experiments leave aspects of responses “up to” participants, neuroscientists must utilize computational techniques such as modeling, simulation, and advanced analyses to progress our understanding of human …

Reduced Growth Mindset As A Mechanism Linking Childhood Trauma With Academic Performance And Internalizing Psychopathology, Lucy A. Lurie, Emily J. Hangen, Maya L. Rosen, Robert Crosnoe, Katie A. Mclaughlin

Neuroscience: Faculty Publications

Background

Despite the high prevalence of childhood adversity and well-documented associations with poor academic achievement and psychopathology, effective, scalable interventions remain largely unavailable. Existing interventions targeting growth mindset—the belief that personal characteristics are malleable—have been shown to improve academic achievement and symptoms of psychopathology in youth.

Objective

The present study examines growth mindset as a potential modifiable mechanism underlying the associations of two dimensions of childhood adversity—threat and deprivation—with academic achievement and internalizing psychopathology. Participants and setting Participants were 408 youth aged 10–18 years drawn from one timepoint of two longitudinal studies of community-based samples recruited to have diverse experiences …

Inhibition Of Acid Sphingomyelinase Reduces Reactive Astrocyte Secretion Of Mitotoxic Extracellular Vesicles And Improves Alzheimer’S Disease Pathology In The 5xfad Mouse, Simone M. Crivelli, Zainuddin Quadri, Hemendra J. Vekaria, Zhihui Zhu, Priyanka Tripathi, Ahmed Elsherbini, Liping Zhang, Patrick G. Sullivan, Erhard Bieberich

Markey Cancer Center Faculty Publications

In Alzheimer’s disease (AD), reactive astrocytes produce extracellular vesicles (EVs) that affect mitochondria in neurons. Here, we show that Aβ-induced generation of the sphingolipid ceramide by acid sphingomyelinase (A-SMase) triggered proinflammatory cytokine (C1q, TNF-α, IL-1α) release by microglia, which induced the reactive astrocytes phenotype and secretion of EVs enriched with ceramide. These EVs impeded the capacity of neurons to respond to energy demand. Inhibition of A-SMase with Arc39 and Imipramine reduced the secretion of cytokines from microglia, prompting us to test the effect of Imipramine on EV secretion and AD pathology in the 5xFAD mouse model. Brain derived-EVs from 5xFAD …

Utilizing Crispr Cas9 To Visualize Dopamine Receptors In Caenorhabditis Elegans, Lauren Michelle Velasquez

Electronic Theses, Projects, and Dissertations

Dopamine (DA) is a neurotransmitter with imperative implications in many functions including movement, reward, and cognition. Studying the pathways of dopaminergic neurons at multiple levels allows us to understand the ways in which these systems can go wrong. We study dopamine in a model system such as the worm Caenorhabditis elegans because of its relatively simple and well-characterized nervous system. DA is involved in regulating chemosensory behaviors in worms. The purpose of this research project is to definitively answer the following question: Are the dopamine receptors DOP-1 and DOP-4 expressed in chemosensory neurons? Previous reporter assays show that neither of …

Novel Insights Into Oligodendrocyte Biology From Developmental Myelination Studies In Autophagy Deficient Mice And Analysis Of Oligodendrocyte Translatome Response To Contusive Spinal Cord Injury., Michael David Forston

Electronic Theses and Dissertations

Loss of myelin causes severe neurological disorders and functional deficits in white matter injuries (WMI) such as traumatic spinal cord injury (SCI). This dissertation is focused on autophagy in OL development and the OL translatome after SCI. Chapter I describes the history of myelin, OL development, and their involvement in neurodegenerative diseases and SCI. The proteostasis network, in particular autophagy, and its contributions to white matter pathology is discussed. It concludes examining advantages and disadvantages of unbiased omics tools, like RiboTag, to study transcriptional/translational landscapes after SCI. Chapter II focuses on autophagy in OPC/OL differentiation, survival, and proper myelination in …

Connectivity Of Amygdala Somatostatin-Expressing Neurons And Their Role In Taste-Guided Behavior., Jane Jeruto Bartonjo

Electronic Theses and Dissertations

The nucleus of solitary tract (NST) and parabrachial nucleus (PBN) represent the first and second central synapses of ascending gustatory information. Neural processing in these nuclei is influenced by descending input from forebrain regions such as the central nucleus of the amygdala (CeA). In mice, we have shown that somatostatin (Sst) expressing neurons of CeA that project to NST and PBN are largely distinct cell populations and optogenetic inhibition of the CeA/Sst-to-NST subpopulation increases the intake of high concentrations of quinine with no apparent effect on sucrose intake. Synaptic connectivity of these cells is needed to understand the possible mechanisms …

A Comparison Of Pm-Nato3’S Influence On Neural Progenitors And Mature Dopamine Neurons, Mary E. West

Masters Theses

This thesis presents significant findings regarding the role of PM-Nato3 in its interaction with developing neurons in the context of Parkinson's disease (PD) and regenerative medicine. We investigated the effects of PM-Nato3 on dopamine (DA) neurogenesis under different culture conditions, both in vitro and in vivo. In the standard dopaminergic culture condition, PM-Nato3 potentially increased the speed of DA neuron production but did not significantly increase the yield of DA neurons. In a minimal culture condition, there was no notable difference between the control and PM-Nato3 conditions, suggesting minimal impact on DA neurogenesis. In vivo studies using a mouse model …

The Genetic Relationship Between Peripheral Inflammation And Alzheimer’S Disease, Davis Cammann

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer’s disease (AD) is the leading cause of dementia worldwide, and has become an ever-present problem in aging populations. An increasing body of evidence suggests that neuroinflammation is one of the key drivers of AD pathology. One overlooked contributor to this burden is peripheral inflammation throughout the body. Due to increased permeability of the blood-brain-barrier (BBB) in older age, inflammatory plasma proteins and immune cells infiltrate the CNS and drive neuroinflammation through interactions with neurons and glia. In addition, age-related changes in the composition of gut microbiome taxa lead to increased gut permeability and inflammatory burden. Because inflammatory factors are …

Methods To Study Activity Dependent Protein Synthesis In Autism Spectrum Disorder, Megan Webb, Karin F K Ejendal, Tamara L. Kinzer-Ursem

Discovery Undergraduate Interdisciplinary Research Internship

It is estimated by the World Health Organization that 1 in 100 children have autism spectrum disorder (ASD), a condition characterized by neurological differences that may impact a person’s learning or behavior. Clinically, ASD symptoms are alleviated with behavioral or pharmacological therapies, however, not all patients respond to these interventions. Deep brain stimulation (DBS) is a promising treatment of Parkinson’s disease that could also be effective in treating ASD. SynGAP1 is a protein involved in neuronal action that is crucial for regulating synaptic plasticity. Mutations in the SYNGAP1 gene causing haploinsufficiency can result in the manifestation of ASD symptoms. This …