Psychological Sciences electronic theses and dissertations (MU)
Permanent URI for this collection
The items in this collection are the theses and dissertations written by students of the Department of Psychological Sciences. Some items may be viewed only by members of the University of Missouri System and/or University of Missouri-Columbia. Click on one of the browse buttons above for a complete listing of the works.
Browse
Recent Submissions
Item Relations between alcohol use, aggression, executive function, and ADHD : a genetic analysis(University of Missouri--Columbia, 2025) Spychala, Kellyn Michelle; Gizer, Ian[EMBARGOED UNTIL 08/01/2026] This dissertation aimed to extend previous studies of executive functioning's (EF) role as a transdiagnostic risk factor for externalizing behavior by using molecular genetic data to examine the etiologic relationships between EF, aggression, alcohol consumption, alcohol use disorder (AUD), and attention-deficit/hyperactivity disorder (ADHD). Study 1 utilized GWAS summary statistics to test whether the shared genetic influences between the traits can be explained in part by similar patterns of enrichment of genes and to identify specific genomic regions contributing to the observed genetic covariation between these traits. Study 2 tested whether the genetic covariation between the traits can be explained by causal, directional relations between EF, alcohol consumption, AUD, aggression, and ADHD using whole genome methods. Finally, Study 3 examined the extent to which the genetic covariation between EF and the externalizing behaviors change across early adolescence and young adulthood. Results from Study 1 suggested EF and the externalizing traits show similar patterns of enrichment and coheritability in several regions across the genome. Study 2 results suggested EF may be a causal mechanism underlying ADHD, alcohol consumption, and AUD, and that ADHD may also causally influence EF. Study 3 results suggested that alcohol consumption and AUD are distinct phenotypes that share some genetic influences; however, limitations in the sample prevented full exploration of longitudinal changes in genetic correlations between EF and the externalizing traits. Together, these results represent novel findings providing evidence for shared etiology among EF and externalizing behaviors.Item Physical activty, sleep, and pain in individuals with chronic pain(University of Missouri--Columbia, 2025) McGovney, Kevin David; McCrae, Christina[EMBARGOED UNTIL 08/01/2026] Introduction Physical activity, sleep, and pain are inter-related such that greater pain is linked to poorer sleep and vice versa, and individuals with chronic pain often avoid physical activity due to anticipated worsening of pain and sleep. The current Dissertation examines whether the relationship between physical activity and sleep is moderated or mediated by pain. Methods A sample of 994 adults (517 no chronic pain, 477 chronic pain) completed a survey measuring physical activity, pain, and sleep. Multiple linear regressions examined whether chronic pain status moderated the relationship between physical activity and sleep. Additionally, two samples of individuals with chronic pain (n=95, n=468) completed two weeks of daily subjective and objective physical activity, pain intensity, and sleep assessments. Multi-level moderation and mediation models examined whether average and daily evening pain intensity moderates or mediates the relationship between average and daily physical activity and sleep. Results Findings were largely consistent across moderation and mediation models such that chronic pain status and evening pain intensity did not moderate nor mediate the relationship between physical activity and sleep. Conclusion The current results suggest that physical activity does not lead to increased evening pain intensity and subsequent impaired sleep. Clinical recommendations regarding physical activity and sleep in healthy adults may largely apply to individuals with chronic pain as well.Item A daily life examination of within-day rumination and negative affect as predictors of alcohol use in young adults(University of Missouri--Columbia, 2025) Fleming, Megan; Trull, Timothy J.[EMBARGOED UNTIL 08/01/2026] Though work suggests individuals drink alcohol to relieve negative affect (NA), findings are mixed with respect to the association between drinking and NA. This may suggest that other factors, independently and in conjunction with NA, precipitate alcohol use. Specifically, rumination may contribute to drinking through its exacerbating effect on NA (Heggeness et al., 2021; Wolitzky-Taylor et al., 2021) and may be a motive for drinking in its own right (Baumeister, 1992; Hull, 1981). Therefore, this study utilized ecological momentary assessment (EMA) to understand the role of rumination as a predictor of whether and how much participants drank in daily life, both as a unique predictor and as a mediator between NA and drinking behaviors. 81 young adult community drinkers (21-29 years old) completed 7+ reports for two weeks via EMA. We hypothesized 1) that rumination experienced prior to drinking would be associated with greater likelihood and quantity of alcohol consumption via EMA, when adjusting for NA and 2) that it would mediate the association between NA prior to drinking and alcohol use. We utilized multilevel modelling to test our hypotheses. Neither hypothesis was supported in the present study. However, within-person total effects of our mediation models suggest associations between negative affect and drinking. Specifically, experiencing greater negative affect prior to drinking was associated with a reduced likelihood of drinking on a given day, but participants tended to consume a greater number of drinks on days characterized by greater negative affect. Though our hypotheses were not supported, this study provides mixed support for theory positing a positive association between negative affect and alcohol use and future directions for elucidating associations between within-person measures of rumination and alcoholrelated outcomes are discussed.Item The default mode network in early-treated phenylketonuria : relationships between functional connectivity, structural integrity, and cognition(University of Missouri--Columbia, 2025) Clocksin, Hayley Elizabeth; Christ, Shawn[EMBARGOED UNTIL 08/01/2026] Phenylketonuria (PKU) is an autosomal recessive condition characterized by a deficiency in the enzyme phenylalanine hydroxylase (PAH), which is necessary for the metabolism of the amino acid phenylalanine (Phe) into tyrosine. When left untreated, PKU is associated with significant neurological and cognitive sequelae. Individuals who are diagnosed early and begin treatment shortly after birth (i.e., early-treated PKU; ETPKU) avoid the significant impairments associated with untreated PKU. However, neurological and neurocognitive disruptions are still noted in this population. Even with the accumulated evidence for disruptions in WM integrity, functional connectivity, and neurocognition, the relationship between these sequelae is not well understood. Resting state functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), and neurocognitive data from 35 adults with ETPKU and a demographically similar comparison group of 32 adults without PKU was analyzed. White matter abnormalities were evidenced by significant reductions in axial diffusivity (AD) among individuals with PKU across several connections within the default mode network (DMN). Within the ETPKU group, recent Phe levels were significantly correlated with AD. Several significant correlations between AD and the neurocognitive composites were identified, although the mediation model relating Phe levels, structural connectivity, and cognition was not supported. Functional connectivity within the DMN was also reduced in the ETPKU group but showed no relationship with Phe levels. Although functional connectivity significantly correlated with structural connectivity in the non-PKU group, non-significant relationships were found among those with ETPKU. The present findings underscore the importance of metabolic control and provides insight into the possible mechanisms underlying neurological and cognitive changes associated with ETPKU. Additionally, the present work suggests that the relationship between functional and structural connectivity is more complicated than in unaffected populations.Item Radical Healing Dialectical Behavior Therapy : a transtheoretical intervention for LGBTQ+ adults(University of Missouri--Columbia, 2025) Bernardin, Courtney Jorgenson; Bell, Debora[EMBARGOED UNTIL 08/01/2026] LGBTQ+ individuals face increased risk for stress-sensitive mental health difficulties in response to the added stress they experience as part of this marginalized group, yet few evidence-based interventions exist to support their mental health. Existing interventions are limited by a lack of attention paid to risk and protective factors that may be particularly important for LGBTQ+ mental health. The purpose of this project was to pilot Radical Healing Dialectical Behavior Therapy (RH-DBT), a group intervention for LGBTQ+ individuals that builds upon existing interventions. Eight participants ages 18 to 54 years completed RH-DBT. Participants also completed pre- and post-intervention measures of psychological symptom distress and risk and protective factors for mental health difficulties, and participated in focus groups to discuss their experiences. Results demonstrated that participants endorsed decreased levels of emotion dysregulation and hopelessness and increases in hope. Four of eight participants demonstrated reliable change on a measure of transdiagnostic psychological symptom distress. In addition, participants rated RH-DBT as highly acceptable and feasible, and provided some recommendations for revisions of the intervention. Overall, it appears that RH-DBT is a promising novel mental health intervention for LGBTQ+ adults.