Translating Extinction Learning Processes to Improve the Understanding and Treatment of Anxiety Disorders

Systematic exposure to feared stimuli is an integral component of cognitive behavioral-based therapies and is often regarded as the 'gold-standard' psychotherapeutic strategy for anxiety-related disorders. While many individuals respond to exposure-based treatments, a significant proportion experience a return of fear after treatment has concluded (e.g., Loerinc et al., 2015) - with others failing to respond to treatment all together (e.g., Taylor, Abramowitz, & McKay, 2012). Over the past several decades, associative learning theory has continued to evolve and has given rise to significant paradigm shifts in our fundamental understanding of fear learning (e.g., Rescorla & Wagner, 1972). These theoretical updates have provided explanations as to why anxious individuals often fail to adequately extinguish fear during exposure and have provided modernized learning principles which may be translated to practice to enhance exposure-based outcomes (e.g., Craske, Liao, Brown, & Vervliet, 2012; Craske, Treanor, Conway, Zbozinek, & Vervliet, 2014; Sewart & Craske, 2019). In addition, our new understanding of these processes also give rise to additional questions regarding potential unidentified, aberrant fear learning processes in anxious individuals which may also interfere with treatment response. This dissertation will include three papers that aim to both enhance our understanding of fear conditioning phenomenology in humans and translate fear learning principles to optimize exposure-based treatments. Study 1 seeks to establish within-session expectancy violation as a more robust predictor of treatment response to exposure therapy when compared with within-session fear habituation. Study 2 seeks to investigate who benefits the most from a pharmacological augmentation exposure therapy that is to proposed to decontextualize extinction learning. Study 3 seeks to further investigate how perceptual similarity impacts return of fear for complex stimuli in individuals with and without anxiety disorders.