Browsing by Subject "Avoidance"

Now showing 1 - 4 of 4
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    Heightened Sensitivity to Improbable Catastrophes As a Pathogenic Marker of Obsessive-Compulsive Disorder: Theory and Experimental Evidence
    (2021-09) Hunt, Christopher
    Although the obsessions implicated in obsessive compulsive disorder (OCD) could theoretically involve any distressing topic, they typically gravitate toward a handful of specific themes (e.g., contamination, religion, sex, etc.). The universality of these themes across OCD patients from different time periods, cultures, and age-groups suggests they are manifestations of a common, underlying process, but little effort has been made to elucidate the identity of this process. One intriguing feature shared across most common obsessions is a heightened concern with consequences that are objectively terrible but highly unlikely (e.g., catching HIV from a door knob, being sent to hell for a fleeting immoral thought). The ubiquity of this particular consequence suggests that OCD may be characterized by an underlying sensitivity to improbable catastrophes (SIC), but this possibility has yet to be explored. The present dissertation sought to address this gap by examining whether OCD symptoms predicted higher anxious reactivity toward unlikely, highly aversive threats across three experimental studies. In the first study, college students with higher OCD symptoms exhibited greater avoidance of improbable, highly aversive threats, as well as greater expectancy and physiological reactivity for improbable threats in general. An extension of this investigation with different types of experimental threats (study two) showed that OCD symptoms predicted heightened expectancy of improbable threats involving both harmful and disgust-related consequences, while relations between OCD symptoms and avoidance of improbable, highly aversive consequences were specific to harmful threats. Finally, study three showed that differences in expectancy, anxiety, and avoidance for improbable threats prospectively predicted changes in OCD symptoms over the first year of college, with indices of anxious reactivity to improbable threat (anxiety, startle, avoidance) emerging as especially predictive among participants who rated the threat as highly aversive. Together, these studies implicate SIC as a novel pathogenic marker of OCD, and suggest its role in the illness may derive from a more general tendency to overestimate the likelihood of improbable outcomes bearing high subjective costs.
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    A move towards studying both pavlovian & instrumental contributions to conditioning abnormalities in the anxiety disorders
    (2013-07) van Meurs, Brian Gregory
    Fear-conditioning experiments in clinical anxiety have focused almost exclusively on passive- emotional, Pavlovian conditioning, rather than active-behavioral, instrumental conditioning. Paradigms capable of eliciting both Pavlovian and instrumental conditioning are thus needed to experimentally study the maladaptive behavioral consequences of Pavlovian abnormalities. One such abnormality is overgeneralization of conditioned fear, a core feature of anxiety pathology. Such generalization can be assessed by studying generalization gradients and until now has only been examined using Pavlovian conditioning. The current study validates a novel paradigm which applies a validated Pavlovian generalization experiment in the context of a `virtual farmer' computer game in which the participant is a farmer whose task it is to successfully plant and harvest crops. While playing the game, shapes are superimposed on the screen with one such shape, paired with shock, serving as the conditioned danger cue (CS+). Generalization stimuli (GS), parametrically vary in similarity to the CS+, but are never paired with shock. While playing the game, participants are given the opportunity to avoid shock (instrumental conditioning) at the cost of poorer performance. Fear-potentiated startle (FPS), skin conductance responses (SCR) and online risk ratings were obtained and each displayed the expected Pavlovian generalization gradient. Instrumental avoidance responses also form a generalization gradient and are strongly associated with Pavlovian indices of generalization (FPS and risk ratings but not SCR). Additionally, FPS at acquisition was a significant predictor of subsequent avoidance behavior. This novel experimental tool will be useful in describing and testing individual differences associated with clinical anxiety.
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    Neurocircuitry of Generalization of Avoidance Behavior following Pavlovian Conditioning in Adults with High and Low Trait Anxiety
    (2016-08) van Meurs, Brian
    One of the cardinal features of many anxiety disorders is maladaptive avoidance. While behavioral avoidance is important for survival and adaptive when danger is present, in the absence of a threat it is maladaptive. Signaled avoidance depends on Pavlovian learning that a neutral conditioned stimulus signals an ensuing aversive unconditioned stimulus. Maladaptive signaled avoidance could therefore result from abnormalities in Pavlovian conditioning. Overgeneralization of conditioned fear is one such abnormality that has been demonstrated in several anxiety disorders. To assess the relationship between anxiety and generalization of signaled avoidance behavior, 22 participants, with a range of trait anxiety scores split into two group of high and low anxiety, completed a generalization gradient, approach-avoidance fMRI task following Pavlovian discrimination conditioning. Results indicated the expected curvilinear generalization gradient in avoidance responses and ratings of risk, with group differences in avoidance responses. There were several functional regions of interest which also demonstrated the expected curvilinear gradient as well as group differences in percent BOLD signal change across the gradient. This was true for both Pavlovian trials, as well as during the decision making stage of the Instrumental trials. There were also several regions in which activations were significantly related to avoidance behavior. These results indicate that individuals with higher levels of trait anxiety are at increased risk of ‘maladaptive’ avoidance of safe stimuli that resemble danger-cues. Moreover brain areas such as the anterior insula and subgenual anterior cingulate cortex, and primary visual cortex, which are involved in the Pavlovian generalization of fear, are also involved in the overgeneralization of the avoidance response. Additional unexpected findings highlight the role of the cerebellum, somatosensory cortex, and gender in production and maintenance of an avoidance response.
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    “We know what you see, so here’s an ad!” Online Behavioral Advertising and Surveillance on Social Media in an Era of Privacy Erosion.
    (2021-06) Sifaoui, Asma
    Technology has helped creating new opportunities for advertisers to better reach their audiences online. Online Behavioral Advertising is one of these strategies that is being used to target specific audiences with personalized messages to specific consumers based on their online behavior and personal information. However, this personalization has impacted how consumers respond to these personalized ads because they may feel that they are continuously monitored and watched by these brands. This feeling is called perceived surveillance. I explain the relationship between the levels of personalization of the ad based on the brand (match vs. mismatch in ad with previous search) and levels of personalization of the ad based on the product (match vs. mismatch in ad with previous search) and advertising effectiveness (i.e., ad avoidance, attitudes, and purchase intentions) through perceived surveillance. By using the Social Contract Theory, I suggest that higher levels of personalization (i.e., match in brand and/or product with previous online search) illustrate a breach in the social contract between brands and consumers. Furthermore, I explain the relationships between perceived surveillance and the advertising outcomes through the Reactance Theory where higher level of perceived surveillance would lead to more avoidance of the persuasive message and more negative attitudes, and lower purchase intention because of the threat to freedom that surveillance creates. This thesis contributes to theory by looking at perceived surveillance as an antecedent to these advertising outcomes and presents a framework to understand consumers’ perceptions of increased levels of personalization. Practically, this study amplifies the need to safeguard consumers’ privacy; thus, advertisers need to align their strategies to better serve their customers.