Understanding How Genetic Mutations Induce Oligodendrocyte Progenitors To Become Cancer Cells, Dennis Huang

Dissertations, Theses, and Capstone Projects

Gliomas are the most devastating adult brain tumors characterized by poor survival rate and limited options for treatment. Previous studies have shown that they are very heterogeneous and can be further sub-classified based on their transcriptional signature and the presence of specific mutations. One such subtype, is the “proneural glioma”, which is characterized by the enrichment in oligodendrocyte progenitor cell (OPC) transcripts and mutations in genes encoding for the tumor suppressor P53 (Trp53) and for Platelet Derived Grow Factor (PDGF) signaling. Since OPCs are the most abundant proliferative population in the adult brain, in this …

Memory Interference In The Lateral Entorhinal Cortex, Omar Ghazy

Dissertations, Theses, and Capstone Projects

Memory interference occurs when previously formed memories disrupt the acquisition or retrieval of new information. A prominent example of proactive interference is latent inhibition (LI), defined as a reduced ability to form or express Pavlovian associations with a stimulus following non-reinforced exposure. The interference-based model suggests that LI arises because the memory that the pre-exposed stimulus is inconsequential interferes with the memory that it predicts a reinforcer.

Because interference increases with age, identifying its neural basis may help prevent or slow cognitive decline. Prior studies using the LI paradigm implicate the entorhinal cortex (EC) in retrieving the memory that a …

When Avatars Go To School: The Effect Of Virtual Reality On Learning And Error Correction, Lauren Barack

Dissertations, Theses, and Capstone Projects

The pandemic in 2020 led to an increasing dependency on technology particularly in learning environments. National educational assessments in the proceeding years have indicated steep, measurable learning loss. While a fully virtual learning environment is not the norm today, we chose to investigate how virtual reality (VR) environments influence learning in college students.

Our primary research goal was to look at how students learn and remember information gathered in virtual spaces. In particular, we examined whether sensory inputs in the VR environment, including spatial audio and haptic feedback, such as vibrations felt in a handheld controller, would help to better …

The Role Of Excitatory Neuromodulation In Managing Variability Of Neural System Output, Omar Itani

Dissertations

Neural systems can generate consistent outputs across a population despite substantial variability in the underlying components of individuals. This dissertation aims to identify mechanisms through which neuromodulation influences the relationship between parametric and output variability in neural systems. Through a combination of theoretical analysis, computational modeling, and data-driven approaches, the research addresses how excitatory neuromodulation can shape population-level activity variability and identifies key patterns that govern the production of consistent neural population output despite underlying parameter variability.

The theoretical foundation is established by considering how excitatory neuromodulation affects population variability in simplified neuronal models. Two fundamental patterns of variability reduction …

Neuroinflammation In The Ventral Tegmental Area Of Chronically Stressed Rats, Marie M. Hafez

Honors Projects

Chronic stress has been associated with maladaptive behaviors in both human and animal research models, but the underlying mechanisms are unclear. In this research study, we sought to define whether stress induces neural inflammation in the ventral tegmental area, the brain region primarily responsible for regulating reward consumption, learning, memory, and addictive behaviors through moderating dopamine release in other brain areas. To do this, male Sprague-Dawley rats were subjected to a chronic intermittent stress paradigm that included stressors such as wet bedding, delayed feedings, social isolation, strobe lights, and forced swims. Following the chronic stress intervention, brain sections were collected …

Comparative Efficacy Of Combined Versus Singular Auditory Alpha-Theta Brainwave Entrainment And Hypnotherapy Modalities In Chronic Pain Management, Jennifer Nicole Leavitt

Doctoral Dissertations and Projects

This experimental quantitative research, a randomized controlled trial, evaluated combined efficacy of auditory alpha-theta brainwave entrainment (BWE) and hypnotherapy in chronic pain management versus each modality alone. Chronic pain is a serious clinical challenge that may benefit from novel, nonpharmacological interventions. Previous studies have demonstrated benefits of both BWE and hypnotherapy for pain; but research on combined effects was not identified. This study hypothesized that a synergistic approach would offer superior pain relief compared to singular modalities. The study utilized a randomized controlled trial design with a sample size of 38 participants, initially, aged 25 to 65 years old, recruited …

The Role Of Cephalic Mechanosensory Bristles In Flight Initiation Of The Oleander Hawkmoth, Daphnis Nerii, Maitri Manjunath

Theses and Dissertations

During flight, insects sense air movement past their bodies via sensory bristles distributed all over their body. These bristles provide mechanosensory feedback to their nervous system, thereby modulating wing motion to cope with ambient wind conditions. In many insect systems including locusts, moths, etc., flight can be rapidly initiated by stimulating a set of bristles called cephalic bristles on their head. Rapid initiation of flight requires diverse, distributed flight-related reflexes to be simultaneously activated.

Thus, we hypothesized that cephalic bristles directly and simultaneously trigger diverse flight-related reflexes. We tested this hypothesis using the Oleander hawkmoth, Daphnis nerii, as our study …

Administering A Mitophagy Inducing Compound (Mic) To Suppress Neuropathology In A Mouse Model Of Alzheimer’S Disease, Zachary Mayeri

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Despite FDA-approved amyloid-beta (Aβ) therapies in Alzheimer’s disease (AD), Tau pathology remains untreated and is closely linked to cognitive decline. Mitophagy, the process of mitochondrial degradation, is vital for maintaining neuronal health, and its dysregulation is implicated in AD. Recently, our lab identified a mitophagy inducing compound (MIC) that extends the lifespan of C. elegans. We hypothesized that MIC would significantly mitigate neuropathology in an AD mouse model. In this study, aged 3x-Tg AD mice were fed an MIC-containing diet, and immunohistochemistry (IHC) was performed on hippocampal tissue to visualize Aβ and phospho-Tau (pTau) lesions. While MIC had little …

Honey Bee & Reward Loss: A Deep Dive Into The Alarm Pheromone, Citlalli Guadarrama

Masters Theses (Archived)

No abstract provided.

The Manifestation Of Synesthesia In The Deaf, Hard-Of-Hearing, And Sign Language User Population, Elizabeth Droubi

Undergraduate University Honors Capstones

This capstone project investigated the prevalence and manifestation of synesthesia—a perceptual condition where stimulation in one sensory pathway triggers automatic, involuntary experiences in another—within d/Deaf, hard-of-hearing (DHH), and sign language user populations. Despite an estimated prevalence of over 4% in the general population and findings that many synesthetic experiences are language-based, little is known about how synesthesia presents across different language modalities, including signed languages. This project explored the phenomenon in two phases: an initial online survey assessing the prevalence and characteristics of synesthesia among DHH and signing individuals and follow-up interviews with self-reported synesthetes along with a test-retest procedure …

Capturing The Representational Dynamics Of Face Perception In Deep Recurrent Neural Networks, Hossein Adeli, Chase W. King, Nikolaus Kriegeskorte

MODVIS Workshop

We investigate the representational dynamics of recurrent convolutional neural networks (RCNNs) in order to understand the time-course of visual recognition. We explore a family of models with bottom-up and lateral connections that were optimized for face-identification and object-recognition tasks. Using representational similarity analysis (RSA), we observed that only models that were trained for face identification showed a late-emerging prominent distinction of identities as seen in the monkey face patch AM. Early model responses strongly separated the objects from the faces. These findings suggest that the dynamics of face recognition that emerges in a hierarchical recurrent neural network prioritizes category-level recognition …

Attention Improves Classification Performance Of Locations In Ventral And Dorsal Visual Pathways, Jinho Lee, Sung-Mu Lee, Ishita Agarwal, Anne Sereno

MODVIS Workshop

Visual processing is divided into a ventral and dorsal pathway, thought to be important for object recognition and spatial cognition, respectively. Yet both streams encode shape and spatial information, and both are modulated by attention and task demands. This study compared how attention influences fMRI bold responses in a ventral region (fusiform gyrus, FG) and dorsal region (superior parietal gyrus, SPG). Specifically, using multivariate pattern analysis within each region, we examined whether attention modulated spatial location classification performance. During fMRI scans, participants performed one of 3 possible tasks: a 1-back task under attend-to-shape (detect a shape repetition); a 1-back task …

Peripheral Neuroimmune Mechanisms Of Chronic Back Pain, Aleyah Esther Goins

Biomedical Sciences ETDs

Chronic back pain (CBP) affects 1 in 10 people worldwide, reducing mobility, productivity, and quality of life. Despite its prevalence, non-addictive treatments remain limited due to an incomplete understanding of chronic pain mechanisms. This dissertation examines peripheral neuroimmune interactions in CBP using a urokinase-type plasminogen activator (uPA)-induced mouse model (uPA-CBP). uPA, a pro-inflammatory serine protease, was injected into the L2/L3 lumbar spinous ligament, inducing prolonged mechanical and cold hypersensitivity. Flow cytometry of dorsal root ganglia (DRG) showed increased CD45+CD11b+ myeloid cells in males and CD45+CD3+CD4+ lymphocytes in females. DRG neurons from male uPA-CBP mice exhibited heightened action potential firing. Pharmacological …

Assessing The Effects Of Streptozotocin-Induced Hyperglycemia On Amyloid Beta Accumulation And Cognitive Behavior In A Mouse Model Of Alzheimer’S Disease-Related Pathology, Andrew Adonay Ortiz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer’s disease (AD) is an irreversible and devastating neurodegenerative disease characterized by progressive synaptic, dendritic, glial, and neuronal loss, collectively leading to impairments in learning, memory, and deterioration of cognitive and behavioral functions. AD is the most common form of dementia accounting for 60-80% of all cases. AD affects approximately 7 million Americans and is the 6th leading cause of death in the US. Furthermore, by 2050, the US is projected to spend over $1.1 trillion on AD-related treatments. Pathological hallmarks of AD include beta-amyloid (Aβ) plaques, intracellular neurofibrillary tangles (NFTs), and chronic neuroinflammation, which can promote and exacerbate both …

Comparing Apples To Oranges From Photoreceptors To Inferotemporal Cortex, Qasim Zaidi, Xu Yi, Akihito Maruya, Bevil Conway

MODVIS Workshop

No abstract provided.

Perceptograms And Cortical Models For Amblyopic Form Distortions, Akihito Maruya, Farzaneh Olianezhad, Jingyun Wang, Jose-Manuel Alonso, Qasim Zaidi

MODVIS Workshop

No abstract provided.

Influence Of Task On The Geometry Of A Perceptual Space, Jonathan D. Victor, Mary M. Conte

MODVIS Workshop

Perceptual spaces are representations of a sensory or cognitive domain in which the domain’s elements correspond to points, and distances between these points are perceptual differences. Proximity relationships within a perceptual space can support a variety of functions, including discrimination, grouping, learning, and generalization. These diverse functions may use the features of the domain in different ways, resulting in task-dependent influences on the geometry of the space.

To identify and characterize these influences, we focused on a domain of visual textures. These textures varied across many dimensions, including mean luminance and low- and high-order spatial correlations, which formed the axes …

Using Neural Networks To Better Understand Static And Dynamic Components Of Facial Expression Recognition, Yi-Fan Li, Anne Bibiana Sereno

MODVIS Workshop

Facial expressions are crucial social information for human communication. In the real world, facial expressions are dynamic; however, much of existing research in facial expressions relies on static stimuli. This static approach may limit the ecological validity of our understanding of the emotional information on faces. Our study aims to investigate the dynamic and static information contained in different emotional categories of facial expressions (e.g., happy, sad). Four convolutional neural networks are introduced as models to be trained with a large-scale dynamic facial expression dataset (short videoclips of 16 frames of 7 different emotional categories) in four different ways: ordered …

Modeling Effects Of Edge Classification And Perceptual Organization On The Appearance Of Disk/Annulus Stimuli, Michael E. Rudd

MODVIS Workshop

In classical theories of sensory psychophysics, appearance matches conducted with simple stimuli consisting of disks surrounded by annuli were posited to probe low-level contrast mechanisms in the visual pathways that computed the approximate luminance ratio between the disk and annulus for the purpose of achieving lightness constancy (Wallach, 1948). Subsequent models have explained such matches on the basis of neural edge integration (Shapley & Reid, 1985; Rudd & Zemach, 2004). Here, I demonstrate that appearances matches made in the disk/annulus paradigm are influenced by at least two types of top-down effects involving edge classification and perceptual organization. I present a …

Fixational Eye Movements Shake Up The Stationary View On Pattern Vision, Lynn Schmittwilken, Marianne Maertens

MODVIS Workshop

No abstract provided.

A Computational Perspective On Segregated Processing And The Privileged Role Of Space In Binding, Anne Sereno, Zhixian Han, Elizabeth M. Frazier

MODVIS Workshop

No abstract provided.

Investigating Undergraduate Conditioned Place Preference Utilizing Virtual Alcohol Stimuli, Nikole A. Rodriguez Torres, Robert Astur, Jeffrey Divino

Honors Scholar Theses

Alcohol use remains a major concern among college students, with binge drinking linked to serious physical and mental health problems. But how much does the environment influence these addictive behaviors? The relationship between environmental cues and alcohol related behaviors is a critical area of study, particularly understanding reward and motivation mechanisms. Binge drinking, common among college students, is associated with a range of negative outcomes such as physical harm, legal issues, poorer overall health, sleep problems, depression, anxiety, and severe thoughts of suicide. In our study, college undergraduates were exposed to two VR rooms: one with alcohol-related stimuli and one …

Neurodevelopmental And Environmental Mechanisms Of Invasion, Proliferation, And Tumor Cell Fate Specification In Glioblastoma, Bianca Lynn Myers

Biomedical Sciences ETDs

Glioblastomas (GBMs) are the most aggressive primary brain tumors, and despite over 50 years of research efforts, the median survival remains at 14 months post-diagnosis. The current standard of care consists of maximal surgical resection radiotherapy with concurrent chemotherapy using temozolomide. However, the highly proliferative and invasive nature of GBM cells renders total resection nearly impossible as tumor cells invade the surrounding healthy tissue. The molecular and environmental drivers of these tumorigenic phenotypes are largely unknown. Here, we demonstrate that the neurodevelopmental transcription factor ASCL1 enhances tumor cell proliferation and invasion while activating the expression of a neural stem cell …

Apolipoprotein E4, Tauopathy, And Brain Injury: Molecular Insights Into Alzheimer's Disease Pathology, Nashanthea J. Roland

Theses & Dissertations

Alzheimer’s disease (AD) is the world’s leading cause of dementia, characterized by progressive atrophy of the hippocampal and cortical brain regions, synapse damage and loss, and a buildup of senile plaques and neurofibrillary tangles composed of β-amyloid peptides and hyperphosphorylated tau, respectively. While age is the most significant risk factor for developing AD, apolipoprotein E4 (APOE4) is the strongest genetic risk factor for AD. Although it is known that APOE4 influences tau pathology, the molecular mechanisms by which APOE4 drives AD pathogenesis and progression remain unclear. In addition to intrinsic contributions to AD, there are many extrinsic factors that can …

The Endocannabinoid System's Influence And Modulation Of Nociception, Doreen M. Flannery

Honors Thesis

The anatomy and physiology of pain is a well-defined pathway where noxious stimuli is processed by different systems in the brain. The central research question of this review is how can we better understand the neurobiological effects pain has, and assess if there is therapeutic potential in using endocannabinoids to modulate these effects. Endocannabinoids are signaling molecules that play a key role at both the cellular and molecular level in modulating both acute and chronic pain by influencing different processes within each level that affect how the body responds to both internal and external stimuli. The endocannabinoid system is a …

The Role Of Presynaptic Proteins In Alcohol Sensitivity And Tolerance, Madhumitha Gundluru

Honors Theses

Mammalian Unc13 (Munc13) and Drosophila Unc13 (Dunc13) are presynaptic active zone proteins essential for synaptic vesicle docking and priming in a neuron. Alcohol binds to the C1 domain of Munc13, which inhibits DAG binding. The reduction in DAG binding by Munc13 decreases the probability of vesicle fusion with the membrane, decreasing neurotransmitter release. Heterozygotes for a Dunc13 loss-of-function allele are behaviorally resistant to alcohol, physiologically resistant to alcohol, molecularly resistant to alcohol, and self-administer significantly more alcohol than control flies. Therefore, genetically reducing Dunc13 mimics a state of alcohol tolerance in the fly. The two main Dunc13 isoforms, Dunc13A and …

Claiming More To Cope: Does Ostracism Increase Overclaiming?, Katy Q. Chen

Honors Theses

In a pre-registered online study, we investigated the relationship between ostracism and overclaiming. Ostracism is the act of deliberately or unintentionally excluding and ignoring others. Overclaiming refers to the behavior of exaggerating one’s knowledge or familiarity with specific topics, often as a way of attempting to present oneself as more knowledgeable or competent than one actually is. Drawing from the temporal need-threat model, we hypothesized that ostracized individuals, as a compensatory response, would likely overclaim more compared to included individuals. This online study simulated a work experience where participants were asked to answer questions about their work-related experiences and opinions. …

Neurodegenerative Disease Mechanisms: Mitochondrial Impairment, Tau Aggregation, And Neuroinflammation As Central Drivers Of Disease Progression, Luis D. Estrella

Theses & Dissertations

The study of the intricate molecular mechanisms behind the pathology of neurodegenerative diseases has become a primary research area in the past decades. The major branches of these studies involve both disease progression and disease pathogenesis, in which neuroscientists have studied, and continue to study, the role that mitochondrial dysfunction, aberrant protein aggregation (like Tau), and immune cell reactions have on these. However, more recent studies have shined light to the fact that these three pathological features are not independent from one another and that their synchronous contributions may be the ultimate driver of neurodegeneration. This dissertation encompasses four different …

Impaired Dnajb2 Response To Heat Shock In Fibroblasts From A Neuropathy Patient With Dnajb2/Hsj1 Mutation: Cystamine As A Potential Therapeutic Intervention, Raj K. Pradhan, Nikolas G. Kinney, Brigid K. Jensen, Hristelina Ilieva

Farber Institute for Neuroscience Faculty Papers

Background and Objectives: Neuropathy is a debilitating disorder characterized by peripheral nerve dysfunction and damage to sensory, motor, and autonomic neurons and their axons. While homozygous mutations in DNAJB2/HSJ1 have been linked to early-onset neuropathy, a heterozygous DNAJB2 c.823+6C>T was discovered in an adult patient with severe sensory–motor polyneuropathy. This mutation is predicted to affect both isoforms of the protein. DNAJB2 (HSP40), a key member of the heat shock protein family, plays a critical role in cellular protection and stress, including response to heat shock. DNAJB2 traffics unfolded proteins to another heat shock protein, HSP70, and activates its ATPase …

Biomarkers That Could Explain Parasite-Induced Behavioral Alterations In The Golden Shiner (Notemigonus Crysoleucas) – Posthodiplostomum System, Laura D. Nicolas

All HCAS Student Capstones, Theses, and Dissertations

Trophically transmitted parasites require an intermediate host to be consumed and often manipulate host phenotype (i.e., morphology, physiology, and/or behavior) to increase predation risk by definitive hosts. Posthodiplostomum is a trematode with a complex life cycle involving snails as first hosts, fish as second intermediate hosts, and piscivorous birds as definitive hosts. In fish hosts, Posthodiplostomum infection has been linked to increased predation, suggesting suppression of antipredator behaviors. However, the specific physiological pathways remained unexplored and changes in the host’s neural, endocrine, and immune systems could be involved. Thus, I examined whether Posthodiplostomum infection intensity was associated with brain serotonin …