Neural Dynamics Underlying Impaired Autonomic and Conditioned Responses Following Amygdala and Orbitofrontal Lesions

A neural model is presented that explains how outcome-specific learning modulates affect, decision-making and Pavlovian conditioned approach responses. The model addresses how brain regions responsible for affective learning and habit learning interact, and answers a central question: What are the relative contributions of the amygdala and orbitofrontal cortex to emotion and behavior? In the model, the amygdala calculates outcome value while the orbitofrontal cortex influences attention and conditioned responding by assigning value information to stimuli. Model simulations replicate autonomic, electrophysiological, and behavioral data associated with three tasks commonly used to assay these phenomena: Food consumption, Pavlovian conditioning, and visual discrimination. Interactions of the basal ganglia and amygdala with sensory and orbitofrontal cortices enable the model to replicate the complex pattern of spared and impaired behavioral and emotional capacities seen following lesions of the amygdala and orbitofrontal cortex.

Rambo's Interdisciplinary Approach to Religious Conversion: The Case of St. Augustine

This dissertation illustrates the merits of an interdisciplinary approach to religious conversion by employing Lewis Rambo’s systemic stage model to illumine the process of St. Augustine’s conversion. Previous studies of Augustine’s conversion have commonly explored his narrative of transformation from the perspective of one specific discipline, such as theology, history, or psychology. In doing so, they have necessarily restricted attention to a limited set of questions and problems. By bringing these disciplines into a structured, critical conversation, this study demonstrates how formulating and responding to the interplay among personal, social, cultural, and religious dimensions of Augustine’s conversion process may eventuate in the consideration of issues previously unarticulated and thus unaddressed. Rambo (1993) formulates a model of religious change that consists of what he calls context, crisis, quest, encounter, interaction, commitment, and consequences. Change is explained by drawing upon the research and scholarship of psychologists, sociologists, anthropologists, and religionists, in conjunction with the contributions of theologians. This study unfolds in the following chapters: I. Introduction; II. Literature review of scholarship about conversion, with emphasis on explication of Rambo’s model; III. A description of the case of Augustine, drawn from a close reading of the Confessions; IV. Literature review of scholarship about Augustine’s conversion; V. Interdisciplinary interpretation of Augustine’s conversion; and VI. Implications for scholars of conversion, and for pastoral caregivers, as well as recommendations for future research. This dissertation demonstrates how Augustine’s conversion experience was deeply influenced by 1) psychological distress and crisis; 2) the quest to know himself and the divine; 3) interactions with significant others; 4) participation in Christian communities; 5) philosophical and cultural changes; and 6) the encounter with the divine. As such, this study reveals the value of interpreting Augustine’s conversion as an evolving process constituted in multiple factors that can be differentiated from one another, yet clearly interact with one another. It examines the implications of constructing an interdisciplinary approach to Augustine’s conversion narrative for both the academy and the Christian community, and recommends the use of Rambo’s model in studies of other cases of religious change.