Neuroscience and Neurobiology Commons^™

Investigating Prefrontal Cortex Neuronal Signatures Of Opioid-Induced Risk-Taking Behavior, Cana Quave

Dissertations and Theses (Open Access)

Opioid use disorder occurs alongside impaired risk-related decision-making, but the underlying neural correlates are unclear. We developed an approach-avoidance conflict task using a modified conditioned place preference procedure to study neural signals of risky opioid seeking in the prefrontal cortex, a region implicated in executive decision-making. Following morphine conditioned place preference, rats underwent a conflict test in which fear-inducing cat odor was introduced in the previously drug-paired side of the apparatus. While the saline-exposed control group avoided cat odor, the morphine group included two subsets of rats that either maintained a preference for the paired side despite the presence of …

Neural Activity Within And Between Visual And Executive Areas Is Modulated Post-Locomotion In Rhesus Macaques, Sergey Egranov

Dissertations and Theses (Open Access)

Physical activity has been shown to benefit cognitive and mental health by improving cerebrovascular perfusion and regulating hormone-mediated processes on a systemic level. However, the acute effects of physical activity, such as locomotion, on the neuronal circuits underlying cognitive processes have yet to be fully characterized. This body of work seeks to rectify this gap in knowledge through analysis of how both behavioral performance and neuronal activity signatures in visual and executive brain regions are modulated post-locomotion in rhesus macaques.

To this end, we performed high-yield electrophysiological recordings simultaneously from area V4, a mid-tier visual cortical region, and the dorsolateral …

Investigating The Role Of The Hypocretin/Orexin System In A Novel Model Of Polysubstance Dependence, Tyler Zarin

Electronic Theses and Dissertations

Substance use disorders (SUD) in the United States are steadily increasing. Potent and dangerous substances such as methamphetamine (MA) and fentanyl (FEN) are often co-used as a polysubstance (POLY), either intentionally or unknowingly as FEN is a common adulterant. SUD is characterized by physiological and psychological dependence involving the negative reinforcement of anhedonia and withdrawal which drive hypermotivated drug-taking behaviors. Current theory suggests that recruitment of hypocretin/orexin (HCRT) neuropeptide in reward and stress associated brain regions contributes to drug dependence. Despite strong evidence for HCRT’s role in mono-drug dependence, a relevant model for POLY dependence has yet to be developed, …

Assessing The Behavioral Impact Of Pyridostigmine Bromide In Rats, Noah A. Martin

Honors Theses

Pyridostigmine bromide (PB) is an organophosphate (OP) nerve agent prophylactic used to protect warfighters against chemical warfare agents. OPs inhibit the neural enzyme acetylcholinesterase (AChE) in the brain. This leads to the buildup of acetylcholine, causing respiratory failure, seizures, and death. PB functions by inhibiting ~30% of peripheral AChE temporarily, protecting the enzymes so that the body is able to restore sufficient cholinergic function post-exposure. PB does not cross the blood-brain barrier, though it may still indirectly affect toxicity in the brain due to repeated AChE inhibition throughout treatment, or by inhibition of non-target ChE’s in the blood. The aim …

Neuroarts And Neuroaesthetics, James Hutson, Piper Hutson

Faculty Scholarship

Recent advancements in neuroarts and neuroaesthetics have elucidated the relationship between artistic engagement and neural processes, emphasizing the impact of aesthetic experiences on cognitive and emotional well-being. Central to this exploration is the NeuroArts Blueprint initiative, which consolidates interdisciplinary research to better understand the impactful role of the arts on brain function and health outcomes. Empirical studies highlight how exposure to art, such as music or visual stimuli, activates neural circuits involved in emotion regulation, memory, and reward processing, particularly engaging the medial orbitofrontal cortex. Innovations such as haptic and electro-tactile devices have introduced novel sensory modalities that not only …

Effects Of Pfos On Zebrafish Dopaminergic Neurodevelopment, Allison G. Fletcher

Research and Creativity Symposium

Per- and polyfluoroalkyl substances (PFAS) are a group of environmental contaminants that cause disruptions to the nervous and endocrine systems. Perfluorooctanesulfonate (PFOS) is considered one of the most disruptive PFAS to the nervous system, and may disrupt neurodevelopment of the dopaminergic system, which has been linked to neurodevelopmental disorders like Attention Deficit/Hyperactivity Disorder (ADHD) in humans. I hypothesized that early life PFOS exposure disrupts the development of the dopaminergic system. To test this hypothesis, I exposed zebrafish to 0.05, 0.5, and 5.0 mg/L PFOS through 5 days of embryonic and larval development. To assess acute effects of PFOS on the …

From Dysbiosis To Dysfunction: Investigating The Effects Of Chronic Cocaine Use On Oral Microbial Shifts And Neuropathogenesis, Douglas E. Johnson

MUSC Theses and Dissertations

Cocaine use disorder remains a significant public health challenge. However, the mechanisms by which chronic cocaine use contributes to neuroinflammation and cognitive decline are still not fully understood. Chronic non-intravenous cocaine use is associated with oral microbial dysbiosis. Although the gut-brain axis has been widely studied, the impact of cocaine-mediated shifts on the oral microbiome on systemic and neuroinflammation remains a significant yet largely unexplored gap. This dissertation investigates the hypothesis that cocaine-specifically enriched oral Streptococcus parasanguinis triggers neuroinflammation, neuropathology, and cognitive deficits. In a human study, the saliva microbiomes from chronic cocaine users exhibited reduced α-diversity, enriched Streptococcus genus, …

Adverse Cognitions: The Impact Of Childhood Trauma On Brain Development, Faith Salamone

2025 Student Academic Showcase

The effect of adverse experiences in childhood have been known to create lasting difficulties, even in adulthood. While it can be hard to determine the effects of childhood trauma on the brain, many studies have identified areas that appear to be negatively impacted by these adverse childhood experiences. This paper is a meta-analysis of eight articles that have attempted to investigate the effects of childhood trauma on the developing brain. These articles are specifically investigating the effects of childhood physical and/or sexual abuse. The areas that will be discussed in this paper are the prefrontal cortex, corpus callosum, the limbic …

Exploring Neural Mechanisms Of Uncertainty Using Eye-Tracking, Olivia Barbarini

Neuroscience Program Student Scholarship

Olivia Barbarini ’26, Neuroscience major

Faculty mentor: Dr. Andra Geana, Neuroscience

The ability to successfully navigate uncertain environments is crucial to human decision-making; this project uses eye-tracking data (gaze and pupil measures) to test how people process perceptual and conceptual uncertainty, and to what extent anxiety influences these processes.

Anxiety- And Compulsivity-Linked Differences In Reinforcement Learning In A Choose-Your-Own-Adventure Game, Tessa Medeiros

Neuroscience Program Student Scholarship

Tessa Medeiros ’26, Biology & Psychology major

Faculty mentor: Dr. Andra Geana, Psychology and Neuroscience

Reinforcement learning (RL) mathematically describes how agents learn to maximize the reward of their environment by understanding and comparing their choice options. This project investigates how anxiety and compulsivity impact the selection of these options and to what extent a text-based, narrative (rather than a game-like environment) changes RL processes in humans.

A Natural Short Sleep Mutation Promotes Longevity Through Mitochondrial Respiration In Drosophila, Pritika Pandey

LSU Doctoral Dissertations

Aging is an irreversible process characterized by progressive physiological decline and an increased risk of metabolic disorders, cognitive impairment, cardiovascular diseases, and neurodegeneration. Disruptions to the circadian clock—whether due to genetic mutations or behavioral factors—accelerate aging and age-related pathologies, highlighting a strong link between circadian regulation and longevity. However, certain individuals harbor a dec2^P384R mutation, which enables natural short sleep without the detrimental effects of chronic sleep deprivation. This suggests that these individuals have evolved adaptations that activate pro-health pathways, allowing them to function optimally with reduced sleep. To investigate the genetic mechanisms underlying these changes, we developed a …

Neuronal Cftr: A Study Of Subcellular Localization And Interactions With Implications For A Role In Synaptic Transmission, Brandon J. Leviskas

LSU Doctoral Dissertations

Protein-protein interactions vary among cell types and the localization of these interactions help to define protein function. The function of cystic fibrosis transmembrane conductance regulator (CFTR) is well established in the context of epithelial tissue due to the debilitating effects of its mutations that cause the disease cystic fibrosis. While in neurons a role has been established in our lab for CFTR in the regulation of cytosolic Cl- in retinal amacrine cells (ACs). This research sets out to learn if CFTR has a synaptic role. Exploring this potential role, localization of CFTR was examined using fluorescent and immunogold labeled transmission …

We Are Our Brains: Disembodied Brain Films In 1950s Cold War America, David P. Pierson

Faculty, Staff, and Alumni Books

Personified Body Parts in Cinema, Literature, and Visual Culture investigates the power of personifying body parts in cinema, television, visual culture, literature, erotica, folklore, and mystique.

Culturally, socially, and poetically exposing hidden aspects and subtleties of human existentialism, this book vigorously questions and problematizes numerous artistic, aesthetic, technological, naïve, and macabre manipulations of body parts for various purposes. A diverse team of authors explore how scribing human traits to limbs, eyes, brains, genitalia, hearts, and other inner organs is grotesque and aesthetic, repealing and appealing, intimidating and intimate, rude and enjoyable, material and spiritual, surprising and mundane. Personified organs are …

How Childhood Maltreatment Shapes Brain Regions: Considerations For Speech-Language Pathology, Alexa G. Sees

Honors Thesis

Childhood maltreatment is a pervasive issue that affects millions of children worldwide, leading to alterations in key structures such as the limbic system, basal ganglia, corpus callosum, visual cortex, and language areas. These changes result in significant cognitive, emotional, and neurological consequences, such as learning deficits, emotional regulation issues, memory problems, reduced vocabulary size, speech errors, etc. This thesis explores the neurological effects of childhood maltreatment and their implications for speech-language pathology, highlighting how maltreatment-induced brain changes affect areas within the scope of speech-language pathology, such as social communication, language development, and behavior management. These results underscore the importance of …

Determinants Of Neuronal Viability Following Spreading Depolarization, Michael C. Bennett

Biomedical Sciences ETDs

Spreading depolarizations (SDs) are massive, slowly propagating waves that cause near-complete neuroglial depolarization and are energetically demanding for the brain. Past studies have established SDs as key contributors to secondary injury in tissue that lacks the metabolic supply to meet the energetic burden of repolarization after SD. Efforts to identify the mechanisms that cause deleterious consequences following SD have been ongoing, with significant results showing that blocking excitotoxic levels of Ca²⁺ from entering neurons through NMDA receptors prevents detrimental outcomes. While these studies have advanced the field, other mechanisms may also contribute to the metabolic burden of SD. This …

Psilocybin Impairs The Extinction Of Contextual Fear In Adult Female, But Not Male, Rats, Lillianna P. Puppel, Aleece K. Al-Olimat, Kylie M. King, Marisa J. Savini, Claire E. Miller, Colin R. Del Valle, Heather R. Sparkman, Brooke E. Bramlage, Phillip R. Zoladz

ONU Student Research Colloquium

Fear-related disorders are often treated with exposure therapy, a technique based on the concept of extinction. However, this type of therapy is ineffective for many individuals, so finding a pharmacological adjunct that augments the extinction of fear could lead to better treatment outcomes. In recent preclinical work, investigators have shown that psychedelics can accelerate the extinction of fear, potentially through their impact on neurotrophic signaling. We previously found that psilocybin exerted sex-dependent effects on the extinction of conditioned fear to an isolated cue (i.e., a tone). Specifically, psilocybin enhanced the extinction of cue fear in male rats but impaired it …

The Role Of Cholinergic Ventral Pallidum Cells In Effortful Motivation, Elizabeth A. Bien

Dartmouth College Ph.D Dissertations

Maladaptive reward-seeking behavior can be driven by one of several different components including excessive craving elicited by cues that predict rewards, failing to effortfully pursue rewards when it is beneficial to do so, and compulsively seeking rewards when it is no longer advantageous to do so. This thesis includes experiments focusing on these three different components of reward-seeking behavior to better understand how reward-seeking can become maladaptive. First, we wanted to examine the role that sex plays in the acquisition and compulsiveness of sign-tracking behavior in the Long Evans rat, a strain that is commonly used as the background for …

The Impact Of Diet-Induced Obesity On Cerebrovasculature Structure And Function, Riley M. Feagle

MUSC Theses and Dissertations

Adequate cerebral perfusion is necessary to help the brain maintain a constant and steady state of nutrient delivery. Since the brain is highly metabolic, changes in the vasculature structure can impact perfusion levels and, therefore, reduce the ability of the brain to receive the support necessary for full functionality. Vascular dysfunction is a common comorbidity among obese individuals. Given the strong association between obesity and cognitive dysfunction, understanding the correlation between reduced cerebral perfusion and altered cerebrovascular structure is crucial. The overall hypothesis of this thesis originated after ample preliminary data, and states that diet-induced obesity reduces cerebral perfusion and …

Activation Of Enkephalinergic Neurons Modulate Pain Within The Brain, Lucy N. Scribner, Oakley M. Statham, Greydon R. Durrant, Callie M. Newson

Student Research Symposium

The endogenous opioid system, consisting of three neuropeptides and canonical receptors, is ubiquitously expressed throughout the brain and is heavily involved in modulating pain[1]. However, research has placed tremendous focus on investigating the receptors of this system, and less attention has been devoted to the peptides. One such opioid peptide, enkephalin, is notably absent within the pain center of the brain, the periaqueductal gray (PAG)[2]. To further understand the role enkephalins play in modulating pain, we aimed to target and activate specific enkephalin-containing neurons that connect to the PAG. By activating these enkephalinergic projections, we hypothesized that this would lead …

Examining Physiological Responses To Misophonic Triggers, Christian O'Reilly, Xuan Yang, Sewon Oh, Doug Wedell, Svetlana Shinkareva

Faculty Publications

We collected and analyzed an array of biosignals (face electromyogram, skin electrodermal activity, peripheral temperature, and electrocardiogram) in 60 participants with and without misophonia, a condition characterized by decreased tolerance to innocuous sounds. Our goal was to objectively characterize the physiological response to misophonia triggering sounds. We found that misophonic responses can be objectively identified in some cases through atypical physiological reactions to triggering stimuli, though not all participants exhibited this response. Our analyses suggest a large interindividual variability in response to misophonic triggers and highlights the need for methodological adjustments in future experiments to increase the detectability of misophonic …

A Reliable And Efficient Detection Pipeline For Rodent Ultrasonic Vocalizations, Sabah Shahnoor Anis, Devin Mark Kellis, Kris Ford Kaigler, Marlene A. Wilson, Christian O'Reilly

Faculty Publications

Analyzing ultrasonic vocalizations (USVs) is crucial for understanding rodents' affective states and social behaviors, but the manual analysis is time-consuming and prone to errors. Automated USV detection systems have been developed to address these challenges. Yet, these systems often rely on machine learning and fail to generalize effectively to new datasets. To tackle these shortcomings, we introduce ContourUSV, an efficient automated system for detecting USVs from audio recordings. Our pipeline includes spectrogram generation, cleaning, pre-processing, contour detection, post-processing, and evaluation against manual annotations. To ensure robustness and reliability, we compared ContourUSV with three state-of-the-art systems using an existing open-access USV …

Deep Jansen-Rit Parameter Inference For Model-Driven Analysis Of Brain Activity, Deepa Tilwani, Christian O'Reilly

Faculty Publications

Accurately modeling effective connectivity (EC) is critical for understanding how the brain processes and integrates sensory information. Yet, it remains a formidable challenge due to complex neural dynamics and noisy measurements such as those obtained from the electroencephalogram (EEG). Model-driven EC infers local (within a brain region) and global (between brain regions) EC parameters by fitting a generative model of neural activity onto experimental data. This approach offers a promising route for various applications, including investigating neurodevel- opmental disorders. However, current approaches fail to scale to whole-brain analyses and are highly noise-sensitive. In this work, we employ three deep-learning architectures—a …

80 - Effects Of Concussion History On Sleep Quality And Memory Function, Aubrey Thames, Amin Mohammadi, Thomas Campbell

Undergraduate Research Symposium

To examine the relationship between sleep quality and memory performance (immediate memory and delayed recall) in athletes with a history of concussion.

Daily Acute Intermittent Hypoxia Elicits Age & Sex-Dependent Changes In Molecules Regulating Phrenic Motor Plasticity, Jayakrishnan Nair, Alexandria Marciante, Carter Lurk, Mia Kelly, Maclain Capron, Gordon Mitchell

Department of Physical Therapy Faculty Papers

Acute intermittent hypoxia (AIH) elicits a form of respiratory motor plasticity known as phrenic long-term facilitation (pLTF). Exposure to repetitive daily AIH (dAIH) enhances pLTF, a form of metaplasticity. Little is known concerning cellular mechanisms giving rise to dAIH-induced metaplasticity and the age-dependent sexual dimorphism of AIH associated pro-plasticity mRNA expression. To test if age, sex, and dAIH effects are associated with differential expression of molecules that regulate the Q- and S-pathways and their cross-talk interactions to phrenic motor facilitation, we analyzed key regulatory molecules in ventral spinal (C3-C5) homogenates from young (3-month) and middle-aged (12-month) male and female Sprague-Dawley …

Androgen Hormones Regulate The Production On The Pain-Inducing Inflammatory Molecule Il-1Β In A Mouse Model Of Inflammatory Pain, Hariharan Ramakrishnan, Geoffroy Laumet, Jaewon Sim

Medical Student Research Symposium

Chronic pain prevalence varies between sexes with a higher incidence and duration reported in women compared to men. This disparity suggests that biological factors, such as sexual hormones, may influence pain perception and development. Among the key players in pain mechanisms, interleukin-1 beta (IL-1β), an inflammatory molecule, has been identified to activate neurons involved in pain sensation. This study explores the hypothesis that sexual hormones, particularly androgens, regulate IL-1β production in inflamed tissues, thereby influencing pain responses. To investigate this, we induced inflammatory pain in male and female mice using Complete Freund’s Adjuvant (CFA), injected into the hind paw. To …

Neural Efficiency Hypothesis In Motor Actions; Spectral Power Of Balancing Ballet Dancers, Carter G. Disantis

Senior Theses

Reduced activity observed during functional imaging of motor experts led to the Neural Efficiency Hypothesis (NEH) in motor skills, which posits that expert performers use fewer neural resources during motor execution than novices, reflecting greater neural efficiency.

This pilot study compared EEG recordings from five novices and four expert ballet dancers during standing and one-leg balance. Whole-brain theta (4–8 Hz) and alpha (8–12 Hz) power were quantified, and topographic maps were generated. In addition to testing the primary hypotheses, the experimental design was evaluated as a practical and scalable approach for investigating the NEH in motor skills. Novices showed significantly …

Early Motor And Language Development In Infants At Elevated Likelihood For Autism, Natalie C. Deal

Senior Theses

During the early stages of infant development, various emerging skills set the foundation for more complex abilities. One such connection is the development of motor skills, which play a crucial role in influencing language outcomes later in the infants' first year. Although these developmental cascades are well understood in typically-developing populations, less is known about the cascade in infants at elevated likelihood for autism spectrum disorder (ASD). Many infants who are later diagnosed with ASD have motor delays or language delays, suggesting that the cascade from motor to language may not be typical in this population. Additionally, little is known …

Individual Differences In The Effects Of A Muscarinic Antagonist On Cued Fear Recall And Extinction, Caitlyn J. White

Senior Theses

Post-Traumatic Stress Disorder (PTSD) is characterized by an inability to extinguish fear after experiencing a traumatic event. The cholinergic system shows increased activity during fear learning and extinction, suggesting a role for cholinergic transmission in PTSD. Our lab has previously found that rats can be divided into extinction resistant (ER) and extinction competent (EC) phenotypes, with ER representing a PTSD-like phenotype. While women are more likely to develop PTSD, there is limited literature on the cholinergic system and recall of cued fear or extinction in female rats which are used as a model system due to their similar brain anatomy. …

Web Application For Simulation Of An Agent-Based Model In Netlogo3d, Chris Davis Perumal, Abraham Nofal, Benedict J. Kolber, Rachael Miller Neilan

Spora: A Journal of Biomathematics

Agent-based models (ABMs) are computer simulation models for studying systems of autonomous agents. Modelers often use specialized software like NetLogo to develop ABMs, but this software poses barriers to researchers in other disciplines with no prior programming experience. To address this issue, we developed a web application that allows users to simulate our ABM via a web browser, eliminating the need for the user to download and use specialized software. While presented in the context of a specific ABM, our approach can be applied to other ABMs to enhance accessibility. The ABM presented here was developed in NetLogo3D. The model …

Effects Of Social Isolation On Locus Coeruleus Opioid Receptor Expression And Affective Behavior, John Tkaczynski, Jordan Riser, Maya Patel, Nicole Shellenbarger, Jin Park, Daniel Manvich, Daniel J Chandler

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Social isolation is a stressor that impairs homeostatic neuroendocrine functions and is associated with the development of several mood disorders characterized by persistent negative affect. Persistent feelings of loneliness have been growing public health concerns for several years and were greatly exacerbated by the onset of the COVID-19 pandemic. The problem has grown so severe the U.S. Surgeon General recently declared loneliness to be an epidemic health concern that is associated with poor mental and somatic health outcomes. Therefore, identifying mechanisms of neuroadaptation that contribute to the development of persistent negative affect is a critical step in the identifying better …