Medicine and Health Sciences Commons^™

Context, Goals, And Operant Behavior: The Role Of The Prelimbic Cortex And Associated Neural Circuitry, Callum Mark Piper Thomas

Graduate College Dissertations and Theses

Operant (instrumental) conditioning is a laboratory model of voluntary behavior. In its simplest form, performing a particular response, such as a lever press, leads to delivery of a reinforcing outcome (e.g., a sucrose pellet). Operant behaviors can be associated with preceding stimuli (“habits”) or outcomes (“goal-directed actions”). A factor that influences performance of operant behaviors is the context in which they are learned. Contexts can be defined as background stimuli that are present during behavior. For example, eating dessert may occur in the context of a restaurant and the sated feeling of a finished meal. The context for eating dessert, …

Investigating The Effects Of Medroxy-Progesterone And Hormonal Birth Control On Habit Behavior In Female Rats, Sarah Charlotte Von Doepp

Graduate College Dissertations and Theses

Recent research has shown that there is a significant sex difference in the rate of habit acquisition in rats, with intact females acquiring the behavior with fewer action-outcome reinforcer pairings than intact males. This difference is shown to be related to the presence of cyclic estrogen and progesterone during habit behavior acquisition training. Specifically, the presence of progesterone has been shown to be crucial in early habit acquisition. However, the mechanism of action through which progesterone is influencing this behavior is unknown. Additionally, this project explores the impacts of long-term hormonal (levonorgestrel - progestin based) birth control on habit behavior …

Towards A Food-Secure Future In An Era Of Uncertainty: Cultivating Resilience In Vulnerable Smallholder Food Systems, Maya Moore

Graduate College Dissertations and Theses

Smallholder food systems in sub-Saharan Africa and other tropical regions are at the crux of the “triple threat” of the Anthropocene: climate change, biodiversity loss and food insecurity. At the same time, they are considered pivotal to the global food system transformation needed to address these challenges. However, while there have been many proposed pathways to achieve desired outcomes, smallholders are often constrained in their ability to adapt and transform. Therefore, in this three-article dissertation, I use mixed methods to study traditional food security coping strategies and apply socio-psychological behavioral intention theories to understand the cognitive factors behind farmers’ decisions …

Determining The Effects Of Castration And Estrogen Replacement On Habit Development In Adult Male Long Evans Rats, Francesca Carasi-Schwartz

Graduate College Dissertations and Theses

During instrumental learning, behavior transitions from goal-directed actions to habits. Goal-directed behavior is driven by the value of the outcome while habitual responding develops with increased training and is characterized by the automaticity with which it occurs independent of outcome value. The dorsal striatum, one of the many regions of the brain that has been implicated in the conversion of goal-directed actions to habits, is sexually dimorphic, and ovarian hormones are known to modulate the expression of habit in females. The present experiments were performed to begin deciphering how gonadal steroid hormones influence habit development in male rats. In each …

The Origins Of Manufactured Dissent And The Efficacy Of Climate Change Narratives, Emma Elisabeth Giering

Graduate College Dissertations and Theses

The year of 2020 revealed many things about the fragility of socially constructed institutions and the public trust which grants such entities legitimacy, which is perhaps what reinvigorated social discourse surrounding the existential threat posed by climate change. Amid a pandemic, Americans watched wildfires engulf much of the west coast, environmental regulations unravel in the hands of the Trump administration, and Wall Street begin trading futures contracts on the U.S.’s water supply. Given the ever-expanding record of environmental travesties, how are citizens to respond, and from where should they derive their inspiration for response?

This thesis answers the above question …

The Role Of Infralimbic Cortex In Switching Between An Instrumental Behavior’S Status As A Goal-Directed Action Or Habit, Matthew Broomer

Graduate College Dissertations and Theses

In instrumental learning, extensive training of a response typically generates a habit. The transition from goal-directed to habitual behavioral control is often considered unidirectional; however, recent evidence suggests this is not the case. Under certain conditions, goal-directed control may be restored to a behavior that was previously habitual. We identify the infralimbic cortex (IL) as a participant in this process and draw on both instrumental learning and fear extinction literatures to further our understanding of IL function.

Four experiments explored the role of IL in flexible behavior. Experiments 1a and 1b were instrumental learning experiments. Experiment 1a used a previously …

Vermont Special Educators’ Perceptions On The Inclusion Of Students With Disabilities In Universal Positive Behavioral Interventions And Supports (Pbis), Cassandra L. Townshend

Graduate College Dissertations and Theses

AbstractOver the last 25 years, there has been an increased body of research on best practices to address the social, emotional, and behavioral well-being of all students in schools. Positive Behavior Interventions and Supports (PBIS) has consistently demonstrated effectiveness in attending to all students’ social, emotional, and behavioral wellbeing – including students with disabilities (Simonsen et al., Feb., 2020). Despite PBIS being implemented in over 27,000 schools in the United States (Horner & Sugai, 2015) and in over 50% of schools Vermont, minimal research has been conducted on the experiences of special educators and their perceptions of PBIS practices on …

Examining Sex Differences In Habit Formation: Effects Of Methamphetamine Sensitization And Contributions Of Ovarian Hormones, Hannah Schoenberg Book

Graduate College Dissertations and Theses

In the early stages of instrumental learning, behavior is goal-directed and sensitive to changes in the value of the instrumental outcome. As learning progresses, an association forms between the response and stimuli within the learning environment, such that after sufficient repetition, responding is evoked automatically in the presence of these stimuli and is insensitive to changes in outcome value. The reflexive nature of these types of behaviors has led to their classification as instrumental habits. The emergence of habitual behavior is thought to involve parallel processes that are mediated by distinct neural substrates. Regions of the prefrontal cortex, amygdala, and …

How And Why Do People Value Nature? An Examination Of Nonmaterial Aspects Of Human-Nature Interactions., Tatiana Marquina

Graduate College Dissertations and Theses

Nonmaterial benefits from nature, often labeled as cultural ecosystem services, represent a core dimension of human well-being. Yet despite their importance, these benefits and associated values remain overlooked in environmental assessments and decisions.

This dissertation applies insights from multiple disciplines to document nonmaterial dimensions of human-nature interactions across geographic contexts and user groups. As nonmaterial benefits can be hard to elicit and measure, this work uses multiple existing data collection methods and tests a novel data collection tool. First, I use a qualitative study design to explore values and stewardship practices associated with urban foraging in New York City, NY. …

Exploring Weight Control Expectancies As A Mediator Of The Relationship Between Fear Of Fat And Nicotine Dependence In Smokers And Vapers, Emily Pomichter

Graduate College Dissertations and Theses

Specific drug-use expectancies are shaped by reports from others about the effects of the drug, by an individual’s own experience with the drug, or by both. The present study hypothesized that, among smokers and e-cigarette users (vapers), an individual’s fear of weight gain would be associated with higher endorsement of appetite and weight control expectancies from nicotine use, which in turn would be associated with self-reported levels of nicotine dependence. The participants were smokers (n = 514) and vapers (n = 412) who responded to a Qualtrics survey advertised via Amazon’s Mechanical Turk platform. As predicted, nicotine’s appetite and weight …

Evaluating The Utility Of The Modified Cigarette Evaluation Questionnaire And The Cigarette Purchase Task For Predicting Acute Relative Reinforcing Efficacy In Cigarettes Which Vary In Nicotine Content, Cecilia L. Bergeria

Graduate College Dissertations and Theses

Rationale: Nicotine is the addictive component in cigarettes which maintains cigarette smoking that subsequently leads to morbidity and mortality. There are growing regulatory efforts to lower the nicotine content in cigarettes so that they are minimally addictive. Valid methods for assessing the abuse liability of cigarettes are essential to these efforts. While subjective effect measures and hypothetical purchase tasks are appealing because they are far easier to administer, it is unclear whether these methods can be used to evaluate acute relative reinforcing, a critical component of abuse liability. This secondary analysis sought to evaluate the utility of one subjective effects …

A Novel Mhealth Application For Improving Hiv And Hepatitis C Knowledge In Individuals With Opioid Use Disorder, Taylor A. Ochalek

Graduate College Dissertations and Theses

Aims: Untreated opioid use disorder (OUD) is associated with overdose, premature death and infectious disease, including human immunodeficiency virus (HIV) and Hepatitis C (HCV). While prior studies have shown that educational interventions are associated with improvements in HIV and HCV knowledge and reductions in risk behaviors, those examined to date have typically been time- and resource-intensive. We recently developed an HIV+HCV Education intervention which aims to improve HIV and HCV knowledge in a single visit using an automated iPad platform. In this project, we examined its ability, using a within-subject evaluation, to improve knowledge of HIV and HCV transmission and …

Cues Associated With Alternative Reinforcement Can Attenuate Resurgence Of An Extinguished Instrumental Response, Sydney Trask

Graduate College Dissertations and Theses

In resurgence, a target behavior (R1) is acquired in an initial phase and extinguished in a second phase while an alternative behavior (R2) is reinforced. When reinforcement for the second response is removed, however, R1 behavior returns or “resurges.” The resurgence paradigm may have implications for understanding relapse after behavioral interventions in humans such as contingency management, or CM, in which (for example) drug users can earn vouchers contingent upon drug abstinence. The present experiments examined the effectiveness of a putative retrieval cue for treatment in attenuating the resurgence effects and determined the likely mechanism by which this cue functions. …

Comparing The Smoking Topography Of Usual Brand Cigarettes In Pregnant And Non-Pregnant Smokers, Cecilia Louise Bergeria

Graduate College Dissertations and Theses

Introduction: Most pregnant smokers report abruptly reducing their cigarettes per day (CPD) by ~50% shortly after learning of pregnancy and of making further smaller reductions over the remainder of their pregnancy. Laboratory and naturalistic studies with non-pregnant smokers have found that these types of reductions often lead to changes in smoking topography (i.e., changes in smoking intensity to maintain a desired blood-nicotine level). 19, 20 If pregnant women engage in compensatory smoking, they may expose themselves and their offspring to the same level of toxicants despite reporting reductions in CPD.

Methods: Pregnant and non-pregnant female smokers (n = 17 and …

Exercise In Developing Rats Promotes Plasticity In The Prefrontal Cortex: Behavioral And Neurobiological Indications, Meghan Eddy

Graduate College Dissertations and Theses

Physical exercise has repeatedly been shown to trigger positive effects on brain function including improved learning, memory, and executive functions. In addition, corresponding physiological changes have been observed, such as increased neurotrophic factors, changes in neurotransmitter concentrations, and increased dendritic spines. However, these changes have not been well described outside of the hippocampus, including the medial prefrontal cortex (mPFC), and have not been directly compared at different points of development. Because the prefrontal cortex is one of the last brain areas to fully mature, considering the age at which intervention, such as exercise, takes place is particularly important. Additionally, in …

Learning Related Regulation Of A Voltage-Gated Ion Channel In The Cerebellum, Jason R. Fuchs

Graduate College Dissertations and Theses

The neural mechanisms that support learning and memory are still poorly understood. Much work has focused on changes in neurotransmitter receptor expression, while changes in voltage-gated ion channel expression have been largely unexplored, despite the fact that voltage-gated ion channels govern neuronal excitability. Here we used eyeblink conditioning (EBC) in rats, a model of learning and memory with a well-understood neural circuit, to examine regulation of voltage-gated ion channels as a consequence of learning. EBC is a form of classical conditioning that involves pairings of a behaviorally neutral conditioned stimulus (CS) and an eyeblink eliciting unconditioned stimulus (US) over many …

Chronic Stress Potentiates The Response To Intra-Bed Nucleus Of The Stria Terminalis (Bnst) Pituitary Adenylate Cyclase Activating Peptide (Pacap) Infusion., Steven Bradley King

Graduate College Dissertations and Theses

Chronic or repeated exposure to stressful stimuli can result in several maladaptive consequences, including increased anxiety-like behaviors and altered peptide expression in brain structures involved in emotion. Among these structures, the bed nucleus of the stria terminalis (BNST) has been implicated in emotional behaviors as well as regulation of hypothalamic-pituitary-adrenal (HPA) axis activity. In rodents, chronic variate stress (CVS) has been shown to increase BNST pituitary adenylate cyclase activating polypeptide (PACAP) and its cognate PAC1 receptor transcript, and BNST PACAP signaling may mediate the maladaptive changes associated with chronic stress. In order to determine whether chronic stress would potentiate the …