Date of Award

Spring 1-1-2015

Document Type


Degree Name

Doctor of Philosophy (PhD)


Psychology & Neuroscience

First Advisor

Mark A. Whisman

Second Advisor

Soo Hyun Rhee

Third Advisor

John K. Hewitt

Fourth Advisor

Matthew McQueen

Fifth Advisor

Naomi P. Friedman


A large body of research suggests that rumination, or the tendency to engage in passive and repetitive thinking about one's own distress, is a robust risk factor for depression, and is also associated with risk for other psychological disorders. However, much less is known about the influences that lead to ruminative thinking and its associations with psychopathology. The present studies were designed to examine these questions and contribute to the limited body of research investigating the etiology of rumination.

Study 1 examined the genetic and environmental influences on rumination and its associations with several forms of psychopathology (depression, anxiety, eating pathology and substance dependence) in a sample of adult twins. Results suggested that rumination was associated with each form of psychopathology. Furthermore, there was evidence of distinct patterns of etiological overlap between rumination and each disorder; results suggested that rumination had considerable genetic overlap with depression, modest genetic overlap with eating disorder symptoms, and almost no genetic overlap with substance dependence. In general, results were specific to ruminative thought and did not extend to self-reflection. These findings support the conceptualization of rumination as a transdiagnostic risk factor for psychopathology and also suggest that the biological and environmental mechanisms linking rumination to psychopathology may differ depending on the disorder.

Study 2 examined several potential developmental risk factors for rumination. Results suggested that stressful environmental contexts, including exposure to parents in a dissatisfying relationship (for males and females) and negative dependent life events in late childhood and adolescence (for females) were associated with greater rumination in adulthood. Additionally, mother, father and child neuroticism were associated with rumination in adulthood for both genders. Importantly, these prospective associations were significant even with 10 to 20 years between the assessments of risk factors and rumination.

In concert, results of these two studies lay a foundation to examine further the environmental and biological factors that increase risk for rumination and subsequent risk for psychopathology. Elucidation of the etiological influences on rumination may guide the development and refinement of interventions aimed at reducing rumination, and mitigate rumination's pervasive effects on health and well-being.