Social and Behavioral Sciences Commons^™

Affective Liking Influences Reward Processing In Depression: A Computational Eeg Approach, Garima Singh

Psychology ETDs

Reinforcement learning (RL) enables agents to learn through interaction with their environment. This empowers individuals to optimize actions in complex and dynamic settings. The component of event related potential (ERP) termed as the Reward Positivity (RewP) evidently signifies a fundamental reward prediction error (RPE) associated with rewards. This characteristic implies that it represents a fundamental computational process in the assessment of RL. When a reward is particularly pleasurable or liked by an individual, it tends to elicit an amplified RewP signal, reflecting the heightened positive affect. RPE arises from disparities between anticipated and actual rewarding outcomes and is known to …

Oral Contraceptives And Affective Disorders: Neurobiology And Informed Choice, Sophia Mae Drezner

Scripps Senior Theses

Pregnancy prevention and female reproductive freedom have been some of the most contested political issues for decades. Abortion, a fundamental part of women’s healthcare, divides liberals and conservatives on an international scale. The consequences of unintended pregnancy without safe and reliable contraception are widespread, disproportionately impacting women of color, trans and non-binary folks, and poorer communities. The birth control pill is the most common form of oral contraception (OC) globally. Many people with ovaries begin the pill or other hormonal contraceptive (HC) methods as young as 11 years old. Exogenous progesterone and estrogen are known to impact mood, affect, physiology, …

Role Of The Default-Mode Network During Narrative Integration In Major Depressive Disorder, Darren Ri-Sheng Liang

Electronic Thesis and Dissertation Repository

How brain activity is synchronized across individuals during narrative comprehension has previously been characterized by functional magnetic resonance imaging (fMRI) in healthy and patient populations. To our knowledge, there has been limited investigation as to how it is affected by major depressive disorder (MDD). We addressed this issue with fMRI through examination of inter-subject synchronization in the default mode network (DMN), brain structures which have previously been implicated in MDD pathology. Twenty-two patients with MDD and 20 matched control participants listened to Intact versus Scrambled versions of an auditory narrative; these experimental conditions differed in the degree of temporal integration …

Behavioral, Physiological, And Molecular Characterization Of Long-Term Administration Of A Novel Estrogen Receptor Beta Agonist In A Mouse Model Of Menopause, Aaron William Fleischer

Theses and Dissertations

The menopausal loss of circulating hormones, including estrogens, is associated with negative symptoms, such as hot flashes, anxiety and depression, cognitive decline, and weight gain. Although estrogenic hormone therapies (HT) prevent many of the negative symptoms related to the menopausal transition, these same therapies are associated with increased health risks, such as the development of breast and ovarian cancers, which is mediated by the activation of the a (ERa), but not b (ERb), estrogen receptor isoform. Furthermore, ERb agonism has previously been shown to reduce preclinical indices of hot flashes, memory decline, anxiety, and depression. As most ERb agonists are …

Influences Of Salvinorin A And Sex Differences On Depressive- And Anxiety-Like Behaviors In A Chronic Mild Stress Paradigm, Sarah Mitchell

Theses

Kappa opioid receptors are colocalized with dopamine receptors and are frequently associated with depression, anxiety, stress, and drug use and abuse. KOR antagonism has widely been considered anti-depressive and anxiolytic in animal models while agonism is pro-depressive and anxiogenic. However, recent findings suggest that SalvA, a natural kappa agonist derived from a plant in the mint family, can reduce depressive- and anxiety-like behavior in rats. The current study investigated the effects of chronic mild stress on behavior, attenuation by SalvA, and sex differences. 52 Long-Evans rats, 26 males and 26 females, were exposed to six weeks of CMS. Animals received …

Ketamine Pre-Exposure Does Not Influence Later-Life Responses To Reward-Related Stimuli In Female C57bl/6 Mice, Israel Garcia

Open Access Theses & Dissertations

Preclinical work indicates that exposure to traditional antidepressant medications, in adolescent and adult female subjects, alters reward-related behavior later in life. In recent years, the anesthetic ketamine (KET), now used as a fast-acting antidepressant, has shown promising therapeutic efficacy for the management of depression. However, the potential long-term behavioral consequences of KET exposure across development have not been thoroughly assessed. Thus, to address this issue, we examined if KET exposure, during adolescence or early adulthood, results in enduring alterations in responsivity to the rewarding properties of sucrose and cocaine later in life. Specifically, female C57BL/6 mice were randomly assigned to …

The Influence Of Neural Reward Processing On Memory In Depression, Nathan M. Hager

Psychology Theses & Dissertations

Theories and research suggest that depression involves impaired reward sensitivity and a deficit in memory for rewarding stimuli. Some researchers propose that this memory deficit may result from reduced neural reward sensitivity, which impairs the encoding of reward-related memories, but few studies have directly probed this connection. Such research may benefit from examining the reward positivity (RewP), an event-related potential (ERP) previously linked to reduced reward sensitivity in depression. Undergraduates with high or low self-reported depression completed a task in which they chose one of three doors, revealing a neutral word written in a color which indicated an outcome of …

Risk Profiles For Adolescent Internalizing Problems, Kelsey Elizabeth Hudson

Graduate College Dissertations and Theses

Objective: Internalizing problems are commonly diagnosed during adolescence, and are associated with distress, impairment, and negative mental health outcomes in adulthood. Thus, there is a critical need to characterize adolescents who are at the highest risk for escalating to clinical levels of internalizing problems while extending current literature and incorporating both biological and environmental predictors. This study aimed to characterized risk profiles for fourteen-year-old adolescents who developed clinical levels of internalizing (High Internalizing [HI]) problems by age nineteen, using brain, genetic, personality, cognitive, life history, psychopathology, and demographic measures. The study also examined whether there were functional and structural brain …

Effort-Related Motivational Dysfunctions: Behavioral And Neurochemical Studies Of The Wistar-Kyoto Rat Model Of Depression, Brendan Abbott

Masters Theses

Depression and related disorders are characterized by motivational dysfunctions, including deficits in behavioral activation and exertion of effort. Animal models of relevance to depression represent a critical starting point in elucidating the neurobiological mechanisms underlying motivational dysfunctions. The present study explored the use of the Wistar-Kyoto (WKY) animal model of depression to examine effort-related functions as measured by voluntary wheel running and performance on a mixed fixed ratio 5/progressive ratio (FR5/PR) operant task. Given the known link between activational aspects of motivation and the mesocorticolimbic dopamine (DA) system, the behavioral effects of d-amphetamine (0.5 and 1.0 mg/kg, IP), a psychostimulant …

Quantifying The Spectrum Of Depression, Octavious Bishop

Walden Dissertations and Doctoral Studies

Walden University

College of Social and Behavioral Sciences

This is to certify that the doctoral dissertation by

Octavious Bishop

has been found to be complete and satisfactory in all respects,

and that any and all revisions required by

the review committee have been made.

Review Committee

Dr. Thomas Edman, Committee Chairperson, Psychology Faculty

Dr. Ricardo Thomas, Committee Member, Psychology Faculty

Dr. Joanna Bissell-Havran, University Reviewer, Psychology Faculty

Chief Academic Officer

Eric Riedel, Ph.D.

Quantifying the Spectrum of Depression

by

Octavious Bishop

MA, University of Texas at Austin, 2008

BS, University of Texas at Austin, 2001

Dissertation Submitted in Partial Fulfillment …

Associations Between Hypothalamic-Pituitary-Adrenal Axis System Gene Variants And Cortisol Reactivity In Preschoolers: Main Effects And Gene-Environment Interactions, Haroon I. Sheikh

Electronic Thesis and Dissertation Repository

Exposure to stressful events during early development has consistently been shown to produce long lasting effects on the hypothalamic-pituitary-adrenal (HPA) axis, which may increase vulnerability to mood and anxiety disorders. Recently reported genetic association studies indicate that these disorders may be influenced, in part, by gene-environment interactions (GxE) involving polymorphisms within the corticotrophin-releasing hormone and monoaminergic system genes. However, little is known about how genetic variants and life stress work to shape children’s neuroendocrine reactivity and emerging symptoms. Therefore, the aim of this thesis is to examine main effects of candidate genes and GxE on the neuroendocrine stress response and …