Acute And Chronic Oral Administration Of Cannabidiol-Dominant Cannabis Products: Sex- And Formulation-Dependent Effects On Anxiety-Like Behavioral Patterns In Rats, Carlos R. Maestas-Olguin

Psychology ETDs

Interest in the anxiolytic-like effects of cannabidiol (CBD), the non-intoxicating phytocannabinoid found within the genus, Cannabis, has grown significantly in recent years. However, preclinical investigations of CBD’s anxiolytic potential often elect to forgo translationally relevant models that maximize external validity in favor of greater internal and mechanistic validity. As a result, the effects of relatively low dose (< 3mg/kg) oral CBD administration on anxiety-like behaviors are not yet fully characterized. The present studies examined the impact of two orally delivered CBD-dominant cannabis products – a “full-spectrum” formulation derived from the whole plant and a CBD isolate derived from the same chemovar – on innate defensive behaviors exhibited by adult male and female rats in various tests of anxiety. Results indicated that acute and chronic low dose oral CBD administration attenuated anxiety-like behavior in rats, regardless of sex or formulation. These findings extend the growing corpus of literature describing anxiolytic-like effects of CBD.

Rhythms Of Hippocampal Function And Memory After Moderate Prenatal Alcohol Exposure, Lilliana May Sanchez

Psychology ETDs

Fetal Alcohol Spectrum Disorders involve morphologic and neurobiological abnormalities in offspring subjected to prenatal alcohol exposure. Although not as well studied as high exposure, moderate prenatal alcohol exposure represents the most common and undetected form in humans. While learning and memory deficits have been well characterized at the behavioral level in humans with Fetal Alcohol Spectrum Disorders and in animal models of moderate prenatal alcohol exposure, few studies have determined the circuit or systems level mechanisms of the behavioral deficits. A complete understanding of the neural bases of memory deficits after moderate prenatal alcohol exposure is needed to ultimately identify …

A Single Administration Of Psilocybin Is Ineffective In Reversing Ptsd-Like Sequelae In A Rat Model Of Stress-Enhanced Fear Learning, Kylie M. King, Marisa J. Savini, Noelle M. Molnar, Evelynn J. Schneider, Savannah E. Straub, Joe Parker, Lillianna P. Puppel, Aleece K. Al-Olimat, Allison M. Bach, Phillip R. Zoladz

ONU Student Research Colloquium

Single treatments with psychedelics produce rapid, long-lasting antidepressant effects. Psychedelics may also exert anxiolytic effects and be useful in treating more complex psychiatric conditions, such as PTSD. However, less is known about the impact of these agents on PTSD-related symptoms. Thus, we aimed to determine whether a single administration of psilocybin could reverse PTSD-like sequelae induced by stress-enhanced fear learning in rats. Sprague-Dawley rats were placed in Context A (circular, white conditioning box) and exposed to several uncontrollable footshocks (Stress) or no footshocks (No Stress). The next day, the rats were placed in Context B (square conditioning box with clear …

Psilocybin And The Related Tryptamine, Norbaeocystin, Exert Acute Anxiogenic Effects That Depend On Sex, Marisa J. Savini, Kylie M. King, Noelle M. Molnar, Evelynn J. Schneider, Savannah E. Straub, Joe Parker, Lillianna P. Puppel, Aleece K. Al-Olimat, Allison M. Bach, Andrew Jones, Phillip R. Zoladz

ONU Student Research Colloquium

Single treatments with psychedelics have demonstrated rapid, long-lasting antidepressant effects. However, psychedelics often produce unfavorable psychoactive effects that could worsen existing psychological distress. Thus, we compared the effects of psilocybin and the related tryptamine, norbaeocystin, on anxiety-like behavior in male and female rats. In Experiment 1, rats were treated with 1 mg/kg psilocybin (PSIL), 1 mg/kg norbaeocystin (NOR), or vehicle 30 min before a 5-min trial on an elevated plus maze (EPM) or in an open field test (OFT). On the EPM, PSIL led to decreased open arm time and fewer arm entries in males and females. NOR led to …

Who Will Grow Our Food In The Future? Factors Influencing A-State Agricultural Student’S Intentions To Enter Production Agriculture, Kamana Kafle

Create@State

The future of agriculture depends on what motivates today’s student to pursue careers in production agriculture. This study identifies key drivers of career intention among College of Agricultural students at A-State using an extended Theory of Planned Behavior framework. Data were collected through a cross-sectional survey and analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM). The model explained a substantial 74.2% of the variance in agricultural career intention. Results revealed that Career Planning was the strongest positive predictor, followed by Attitude Towards Agriculture and Perceived Value. Interestingly, factors such as Perceived Behavioral Control, Subjective Norms, and access to Facilities …

Fit Check: Making Health Assessments Work For You, Brooklynn Raacke, Ryssa Schlaefli, Caleb Ashley, Makenzie Premer, Brooke Mann, Jessica Phelan

SACAD: Scholarly Activities

When given multiple tools to assess health, people tend to choose the one that is most familiar, fastest, or easiest to interpret. Relying solely on weight can overshadow other important indicators of health, such as body composition, cardiovascular function, and muscular development. Understanding this preference, even when other tools are available, matters for both educators and fitness professionals. This study used naturalistic observation to assess gym-goers' usage of health and anthropometric assessment tools. Results indicated that while gym-goers initially showed interest in less commonly used assessment tools, they overwhelmingly used the scale. Implications, limitations, and future directions are discussed.

The Evolution Of Self-Awareness In Conscious Organisms, Robert A. Dielenberg

Journal of Conscious Evolution

Self-awareness in conscious organisms remains an enduring puzzle for philosophers and neuroscientists. This paper proposes a tripartite evolutionary model tracing its emergence through three sequential types: the sensory self (primitive egocentric, valence-tagged awareness of sensory states), the bodily self (external objectification of the body as a distinct entity, evidenced by mirror self-recognition in select species), and the cognitive self (internal objectification of the mind enabling recursive self-transformation). Adopting a monist framework, the model treats consciousness as the biological substrate of delayed neural apperception (the “Delayed Present”), within which selves emerge as increasingly sophisticated models. It distinguishes non-human metacognition—implicit, online regulation—from …

From Meaning To Memory: Assessing The Capacity And Representational Structure Of Visual Working Memory With Meaningful Stimuli, Yong Hoon Chung

Dartmouth College Ph.D Dissertations

Visual working memory is thought to be strictly limited. Yet we remember meaningful, real-world objects better than abstract stimuli. Here I show that this advantage arises from the semantic structure of meaningful objects, not their perceptual features alone, and that it extends even to memory for associated features such as color. In the brain, meaningful objects elicit greater and more distributed delay activity, consistent with the recruitment of higher-level neural processes during maintenance. I propose that semantic knowledge adds representational dimensions that make items more distinctive, and that these dimensions are organized hierarchically with lower-level visual features. These findings recast …

Face Value: A Computational Approach To Subjective Impressions Of Faces, Kevin Kpankou

Undergraduate Research Symposium

Various computational models of first impressions have been developed to uncover the mechanisms driving these judgments. However, the implicit notion of a singular ``human'' often overlooks meaningful individual differences in beliefs, attitudes, and associations, as well as culturally grounded group-level constructs. In this paper, we extend Cultural Consensus Theory (CCT) to estimate culturally shared beliefs about faces by incorporating latent constructs structured around interpretable facial features extracted via computer vision algorithms. We apply our model to a large-scale dataset of people’s first impressions of faces. Our approach reveals a robust mapping between facial features and culturally constructed impressions, allowing us …

Unveiling The Precision Of Physiological Signals In Prediction Error During Fear Learning: Insights From Associative Strength And Generalized Uncertainty, Haja H. Jallo-Jamboria

Dissertations, Theses, and Capstone Projects

Prediction error (PE) is the discrepancy between expected and actual outcomes. It is a central mechanism in associative learning particularly within fear-conditioning paradigms. Identifying physiological markers of PE in aversive contexts has important implications for refining learning models and enhancing clinical interventions for anxiety-related disorders. This study examined skin conductance response (SCR) as a potential physiological index of PE by analyzing both anticipatory and omission-related responses across multiple learning phases. Participants completed a Pavlovian fear-conditioning paradigm in which two conditioned stimuli (CS+) signaled threat at different reinforcement probabilities: CS+100 (certain threat) and CS+50 (uncertain threat), alongside a non-reinforced safety cue …

Exploring The Processing Of Objects, Settings, And Global Properties In Natural Auditory Scenes, Margaret A. Mcmullin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Our auditory system has a remarkable ability to make sense of complex environments, allowing us to identify what we are hearing and where sounds come from. This process of auditory scene analysis is essential for situational awareness, decision-making, and effective communication in daily life. While much is known about how listeners segregate and identify individual sound sources (e.g., voices), less is understood about how global properties of a scene (e.g., openness, naturalness) contribute to perception. This dissertation examined how object- and setting-level information in natural auditory scenes are processed, and whether they rely on distinct or overlapping mechanisms. In Experiment …

Demographic Characteristics And Selected Personality Traits Of Women In Competitive Bodybuilding, Chloe A. Zeeuw

Master's Theses

This study investigated demographic characteristics and measures of personality (dimensions of performance perfectionism and five-factor model characteristics) in women in competitive bodybuilding between 18-25 years old. A total of 24 women completed an online survey which included a demographic questionnaire, the Five Factor Model Rating Form (FFMRF), and the Performance Perfectionism Scale for Sport (PPSS) inventories. Descriptive results for the FFMRF were Openness (18.17±3.12), Conscientiousness (25.58±3.33), Extraversion (19.96±3.46), Agreeableness (19.88±4.58), and Neuroticism (15.67±4.94), and for the PPS-S were Self-oriented performance perfectionism (20.96±3.53), Socially prescribed performance perfectionism (13.96±4.26), and Other-oriented performance perfectionism (10.54±4.23). Pearson’s correlation coefficients and Shapiro-Wilk tests revealed that …

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 …

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. …

Investigating The Effects Of Sod1 Knockout On Oxidative Stress And Stress Coping Styles In Zebrafish Using Crispr Technology, Tai Prauner, Ryan Wong

Theses/Capstones/Creative Projects

Reactive oxygen species are byproducts of cellular metabolism that, when not efficiently neutralized, can damage DNA, proteins, and lipids. Superoxide dismutase 1 (SOD1) is an antioxidant enzyme that converts superoxide radicals into less harmful molecules. While its molecular function is well documented, the role of SOD1 in shaping stress-related behavior remains underexplored. This project aimed to establish foundational tools for studying the behavioral impact of SOD1 knockout across proactive and reactive stress-coping styles in zebrafish.

To support future gene-editing experiments, microinjection and breeding protocols were refined across wildtype AB, proactive, and reactive zebrafish lines. No embryos were injected with CRISPR-Cas9 …

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 …

Impact Of Acute Stress On Circadian Rhythm Regulation Of Locomotor Activity In Syrian Hamsters, Raquel A. Villarreal, Laura E. Garcia, Mario Gil

Research Symposium

Background: Disruptions of circadian rhythms, caused by factors such as environmental changes or stress, are linked to health conditions, including metabolic disorders, cardiovascular diseases, and mood disorders. Circadian rhythm disturbances are particularly relevant for understanding the etiology of conditions like insomnia, depression, and anxiety. The circadian rhythm, primarily regulated by the suprachiasmatic nuclei (SCN) in the hypothalamus, coordinates biological processes to align with daily environmental cycles. Acute stress, especially when experienced immediately upon waking, has been shown to disrupt these rhythms, impair sleep regulation, and exacerbate mood dysregulation. Given the significant clinical implications, understanding how stress impacts circadian rhythms is …

Identifying Personality In Reptiles And Assessing Welfare Implications For Their Roles As Ambassador Animals In An Educational Setting, Valery Gonzalez

Theses and Dissertations

This study examined behavioral variability and personality in 13 reptiles used as ambassador animals at the American Museum of Natural History. Observations across seasons and novel object tests revealed individual differences, behavioral components, and correlations. Findings emphasize reptilian complexity, highlighting welfare implications while underscoring the need for further research.

High Fat Diet & Social Isolation: Interactive Effects On Pain, Cognition, & Neuroinflammation, Ian M. Campuzano

Research Psychology Theses

Prior research has established a role for both social isolation and exposure to high fat Western diets in altering a range of behaviors from reduced memory performance to increased depression-like behaviors. The present study scrutinizes the interplay among these variables during the peri-adolescent developmental phase, utilizing Long-Evans rats as the experimental model. Our overarching hypothesis is that rats exposed to either social isolation, a high-fat diet, or both will result in heightened pain sensitivity, diminished cognitive flexibility, and increased neuroinflammatory responses within brain regions implicated in sociability, cognition, memory, and pain processing. Behavioral flexibility will be assessed using a maze-based …

Exploring Producers' Willingness To Pay For Ecosystem Services: Three Essays On Soil Health, Location Preferences, And Cover Crop Adoption, Kaouter Essakkat

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation comprises three essays: one assessing Midwest producers' willingness-to-pay (WTP) for soil health-enhancing ecosystem services (ES), another examining the impact of policy implementation locations on WTP, and a third identifying factors influencing producers' adoption of cover crops (CC).

The first essay pioneers the understanding of agricultural producers’ valuation of soil health-associated ES amid growing concerns of soil degradation due to agricultural intensification. Using a discrete choice experiment, this study assesses producers’ WTP for a policy that incentivizes ES provision, specifically improved water quality, carbon sequestration, and enhanced crop yield. Surveying producers across Iowa, Kansas, and Nebraska, our results show …

Mate Guarding Against Strong Men Displaying Affiliative And Aggressive Humor, Jacob Pauley

Biological Sciences Undergraduate Honors Theses

Mate retention behaviors serve to discourage partner defection from a current pairbond. Such behaviors are oftentimes more prevalent toward intrasexual rivals exhibiting physical and behavioral cues implicating that rival as an optimal mate. Among these features in men are their upper body strength, a feature diagnostic of heritable fitness, and men's ability to produce humor, a cue to their social competence. This study considered the intersection of these desirable features in shaping men's mate retention behavior toward an intrasexual rival. After learning of a hypothetical interloper exhibiting high or low upper body strength while similarly using humor in an affiliative …

Opioid System's Potential Involvement In Ketamine's Cognitive And Antidepressant-Like Effects In Rats, Fan Zhang

Theses and Dissertations

Depression stands as one of the most pervasive mental health challenges worldwide, including the United States. Conventional antidepressants typically display a delayed onset of therapeutic action (4-8 weeks) and lack efficacy in a substantial portion of patients (over 40% of depressed patients are treatment-resistant). The dissociative anesthetic ketamine, which is a glutamatergic N-methyl-D-aspartate (NMDA) antagonist, has emerged as a promising novel treatment due to its rapid and prolonged antidepressant effects, and it is especially beneficial for treatment-resistant depression. Nevertheless, the precise neurochemical mechanisms underlying ketamine’s antidepressant properties remain elusive, hampering the development of safer and more efficacious treatments. The present …

I Just Don't Want To Hear It: A Look Into The Relationship Between The Dark Triad And Negative Criticism, Carson Montgomery Hewitt

Graduate Theses/Dissertations

Three dark personality traits have been identified and grouped together to form what is known as the Dark Triad of personality. Narcissism, Machiavellianism, and Psychopathy are all connected by a lack of emotional empathy, and the presence of interpersonal hostility. When presented with negative stimuli, it is far from surprising to see an adverse reaction appear in participants scoring high in these traits. Little research has been conducted regarding the relationship between physiological response and dark triad personality traits. Even fewer so in the case of responses to criticism. This study aimed to examine the relationship between these dark personality …

Sex Differences In Stress Reactivity And Responses To Novelty In The Gray Short-Tailed Opossum (Monodelphis Domestica), Esperanza I. Alaniz, Nicole Altamirano, Joseph Rafac, Katelynn Renteria, John L. Vandeberg, Mario Gil

Research Colloquium

Introduction: Investigating how exposures to stress and novel environments influence behavior is important for translational research that aims to improve mental health. Previous studies have focused on reactions to novelty and revealed changes in defense reactions and exploratory behavior. (Pisula et al., 2012).

Objective: The focus of the present study is to investigate sex differences in behavioral responses to novel environments and restraint stress in the gray short-tailed opossums (Monodelphis domestica). Using the Monodelphis is innovative because it is a non-traditional animal model that is ideal for developmental research.

Methods: Using AnyMaze video tracking software, animals’ behaviors (6 males, 6 …

Sex Differences In Stress Reactivity, Brain Morphology, And Oxytocin In The Hypothalamus Of The Gray Short-Tailed Opossum (Monodelphis Domestica), Esperanza I. Zacarias, Daniela Rodriguez, Alexandra Chalons, Sasawan Heingraj, Nicole Altamirano, Joseph Rafac, John L. Vandeberg, Mario Gil

Research Colloquium

Understanding the effects of stress on behavior and cognition is important due to its impact on mental health and wellbeing (Schneiderman et al. 2005). Translational animal research can contribute to the development of new treatments that can improve therapeutic outcomes and our understanding of the neurobiology of stress. In the present study, we complement behavioral stress reactivity with immunohistochemical localization of oxytocin in the hypothalamus, a neuropeptide that regulates stress (Neumann & Slattery, 2016). Oxytocin has potential therapeutic use for mental health disorders (Neumann & Slattery, 2016), and the effects of oxytocin seem to be sexually dimorphic (Love, 2018). Using …

The Impact Of Biological Sex On Motor Function And Responses To Novel Environments In The Gray Short-Tailed Opossum (Monodelphis Domestica), Esperanza I. Alaniz, Ismael Perez, Sasawan Heingraj, Katelynn Renteria, Cristian M. Botello, Joseph C. Cantu, John L. Vandeberg, Mario Gil

Research Symposium

Background: Understanding the different stress reactions in different environments can help us understand stress factors. Studying animal behavior is important for translational research for mental health improvement.

Previous literature has shown that stress is a risk factor for higher cancer incidence and poorer cancer survival. (Klejbor & Turlejski., 2012), as well as mental health outcomes. Understanding of how stress is related to cancer can help improve therapeutic outcomes as preventive measures (Glaser et al., 1987).

Methods: Using the Rota Rod apparatus, 12 animals (3 males, 9 females) were tested at 36 rpm for a maximum of 400 seconds (Madroñal et …

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 …

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 …

Local Field Potentials In The Male Rat Nucleus Accumbens During Effort-Based Behavior, Celine Aliko, John Salamone, Alev Ecevitoglu

Honors Scholar Theses

Major depression is a devastating disorder that consists of multiple symptoms such as low mood and motivational dysfunction. It has been shown that motivational dysfunction can be studied in animal models by using effort-based choice paradigms, which vary in their response requirements. It has been reported that dopamine depletion in the nucleus accumbens decreases ratio-scheduled lever-pressing in a manner related to the size of the ratio requirement. One dopamine depleting agent is tetrabenazine (TBZ), which has been shown to decrease lever-pressing and induce low-effort bias. The current study aims to investigate behavioral and electrophysiological changes that occur with animals performing …

The Reinforcement Enhancing Effects Of Delta-9-Tetrahyrdrocannabinol (Thc) In Male And Female Rats, Kynah Walston

Electronic Theses and Dissertations

Cannabis is widely consumed by humans for pharmacological effects that are mediated by THC, though there is little evidence that THC is a primary reinforcer in non-human animal models. We hypothesized that THC may have potent reinforcement enhancing effects, comparable to other drugs (e.g., nicotine and caffeine) which are also widely consumed by humans, but difficult to establish as primary reinforcers in non-humans. In three experiments with male and female rats saccharin (SACC) or a visual stimulus (VS) served as reinforcers for operant behavior. We explored several pharmacological parameters of THC on responding for SACC or VS, including THC dose, …