Psychology Commons^™

Neural Hyperactivity During Value-Based Decision-Making In People With Daily/Near Daily Cannabis Use, Miranda Ramirez

Theses and Dissertations--Psychology

Value-based decision-making involves the coordinated effort of multiple brain regions to guide future choices based on past experiences. These processes are disrupted in cannabis use disorder, where individuals continue to use cannabis despite negative consequences. Reinforcement learning (RL) paradigms can be used to capture changes in the value of available options and may inform how the brain is impacted by frequent cannabis use. This study combined fMRI with behavioral modeling of probabilistic choice task data to compare value-based choices between young adults reporting daily/near daily cannabis use (CAN) and controls (CTRL). Participants selected one of two options reinforced ($0.25) at …

The Effects Of Extended Fructose Access On Relative Value And Demand For Fructose, Saccharin, And Ventral Tegmental Stimulation, Megan Halloran

Theses and Dissertations--Psychology

Globally, food addiction (FA) is a growing area of research and is largely attributed to the availability of foods that are both energy dense and high in fats and sugars. Further, it has been suggested, that sugar and fat, when consumed frequently, have properties similar to drugs of abuse. While the validity of FA is questioned, researchers have drawn parallels between substance use disorder (SUD) and FA. For example, sugar binge models emphasize craving, withdrawal and binging as primary components of FA, which are also hallmarks of SUD. Additionally, both natural rewards, like sugars, and drug rewards act on the …

Calcium Imaging Of Central Amygdala Activity After Fentanyl Escalation, Samantha Malone

Theses and Dissertations--Psychology

Evidence suggests that rats given long access (LgA) sessions to self-administer (SA) opioids escalate their intake, while also showing greater withdrawal severity and drug-induced reinstatement compared to rats maintained on short access (ShA) daily SA sessions. Little is known about the neural changes that occur during opioid escalation that may impact withdrawal and relapse. Past work examining opioid SA using ShA sessions in rodents has identified the central amygdala (CeA) as an area of interest that becomes hyperactive in acute withdrawal and may be involved in the incubation of craving that occurs after protracted withdrawal. However, these studies have not …

Religious Beliefs And Behaviors As Predictors Of Substance Use In First-Year College Students: A Longitudinal Study, Hannah B. Mcgee

Theses and Dissertations--Psychology

Substance use is prevalent on college campuses (e.g., Douglas et al., 1997) and can create significant negative consequences (Kodjo & Klein, 2002; NIAAA, 2006). Research suggests that religious beliefs and religious behaviors interact to predict risky substance use in first-year undergraduate students, such that students with religious beliefs but no corresponding behaviors are at risk for significant alcohol use and related problems (Brechting et al., 2010; Cole et al., 2020). However, these studies have only been cross-sectional in nature.

The current study assessed longitudinally if the interaction of religious beliefs/behaviors influenced first-year undergraduate student substance use across the early adjustment …

Ethanol Sustains Phosphorylated Tau Protein Immunofluorescence In The Cultured Neonatal Rat Hippocampus: Implications For Fetal Alcohol Spectrum Disorders, Caleb Seth Bailey

Theses and Dissertations--Psychology

Fetal Alcohol Spectrum Disorders (FASDs) are comprised of developmental, behavioral, and cognitive abnormalities caused by prenatal alcohol exposure, affecting an estimated 2%-5% of childrenand costing up to $4 billion annually in the United States alone. Although some behavioral therapies can help, the biochemical mechanisms that underpin FASDs need further elucidation for development of more efficacious therapeutics. The tau protein modulates cytoskeletal structure in neurons, and thereby plays an integral role in proper development and function of the central nervous system, but its function is altered by its phosphorylation state, such that increased phosphorylation reduces tau protein function. The tau protein …

Neurobehavioral Measurements Of Natural And Opioid Reward Value, Aaron Paul Smith

Theses and Dissertations--Psychology

In the last decade, (non)prescription opioid abuse, opioid use disorder (OUD) diagnoses, and opioid-related overdoses have risen and represent a significant public health concern. One method of understanding OUD is as a disorder of choice that requires choosing opioid rewards at the expense of other nondrug rewards. The characterization of OUD as a disorder of choice is important as it implicates decision- making processes as therapeutic targets, such as the valuation of opioid rewards. However, reward-value measurement and interpretation are traditionally different in substance abuse research compared to related fields such as economics, animal behavior, and neuroeconomics and may be …

Measuring Glutamate And Oxygen In Brain Reward Circuits In Animal Models Of Cocaine Abuse And Decision-Making, Seth Richard Batten

Theses and Dissertations--Psychology

Drug-specific reward and associated effects on neural signaling are often studied between subjects, where one group self-administers drug and a separate group self-administers a natural reinforcer. However, exposure to drugs of abuse can cause long-term neural adaptations that can affect how an organism responds to drug reward, natural reward, and their reward-associated stimuli. Thus, to isolate drug-specific effects it is important to use models that expose the same organism to all of the aforementioned. Multiple schedules provide a means of dissociating the rewarding effects of a drug from the rewarding effects of food within a single animal. Further, drug users …

Cocaine Choice: A Novel Procedure For Investigating Neuronal Activation Mediating Cocaine Preference, Jonathan Jenn-Sheng Chow

Theses and Dissertations--Psychology

Cocaine use disorder is a significant health problem, negatively impacting individuals afflicted. While preclinical self-administration research has provided invaluable insight into the neurobehavioral mechanisms that underlie cocaine abuse, cocaine use outside of the laboratory occurs within an environment where other goods are also available ubiquitously. Although there is an ever-increasing literature investigating drug vs. non-drug choice in rodent models and how alternative goods can compete with the subjective value of cocaine, the neurobiological mechanisms that are associated with cocaine preference remains largely unknown. Additionally, current drug vs. non-drug choice studies use procedures that confound preference with intake, such that preference …

Loss Aversion In Cocaine Users: Influence Of Risk And Commodity Type, Justin Charles Strickland

Theses and Dissertations--Psychology

Numerous studies in behavioral economics have demonstrated that individuals are more sensitive to the prospect of a loss than a gain (i.e., loss aversion). Although loss aversion has been well described in healthy populations, little research exists in individuals with substance use disorders. The purpose of this study was to comprehensively evaluate loss aversion in cocaine users. Participants completed measures designed to assess loss aversion for drug and non-drug commodities under varying risk conditions. Cocaine demand was determined using a cocaine purchase task. Cocaine users showed a loss aversion score that was consistent across commodity and risk conditions. Compared to …

Attentional Bias And Alcohol Abuse, Jessica Jane Weafer

Theses and Dissertations--Psychology

Selective attention towards alcohol-related cues (i.e., “attentional bias”) is thought to reflect increased incentive motivational value of alcohol and alcohol cues acquired through a history of heavy alcohol use, and as such attentional bias is considered to be a clinically relevant factor contributing to alcohol use disorders. This dissertation consists of two studies that investigated specific mechanisms through which attentional bias might serve to promote alcohol abuse. Study 1 compared magnitude of attentional bias in heavy (n = 20) and light (n = 20) drinkers following placebo and two doses of alcohol (0.45 g/kg and 0.65 g/kg). Heavy drinkers displayed …