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Full-Text Articles in Psychology
Neural Substrates Of Active Avoidance And Its Impact On Fear Extinction, Elizabeth Parisi
Neural Substrates Of Active Avoidance And Its Impact On Fear Extinction, Elizabeth Parisi
Theses and Dissertations
Models of anxiety suggest that avoidance of a conditioned fear stimulus prevents new safety learning, thereby serving to maintain fear. However, there is little empirical data in humans on the impact of avoidance of conditioned fear stimuli on subsequent fear extinction. In the present study I investigated the effect of avoidance of threat on neural activity during avoidance/control and a subsequent extinction phase using ultra high-resolution (7T) fMRI. Results indicated that active avoidance was associated with increased activity in regions involved in reward prediction, but this did not differentiate active avoidance from an active control condition. Neural activation during the …
Contextually Modulated Avoidance Behavior In Rats Post-Pavlovian Extinction, Lauren Branigan
Contextually Modulated Avoidance Behavior In Rats Post-Pavlovian Extinction, Lauren Branigan
Theses and Dissertations
The following study sought to examine the psychological substrates of renewal (e.g.., context dependent extinction processes) for conditioned avoidance behaviors in rats. Using signaled active avoidance conditioning, rats acquired two-way shuttle responding, to two different auditory stimuli. These behaviors were then extinguished through exposure to the auditory stimuli where shuttling behavior was now without consequence. Subjects were then tested for renewal of avoidance in three distinct renewal sequences (e.g., ABA vs ABB, AAB vs AAA, and ABC vs ABB) in three separate groups of rats. It was found that subjects showed more responding to a stimulus presented outside of its …
The Role Of The Amygdala, Retrosplenial Cortex, And Medial Prefrontal Cortex In Trace Fear Extinction And Reconsolidation, Janine Lynn Kwapis
The Role Of The Amygdala, Retrosplenial Cortex, And Medial Prefrontal Cortex In Trace Fear Extinction And Reconsolidation, Janine Lynn Kwapis
Theses and Dissertations
A wealth of research has outlined the neural circuits responsible for the consolidation, reconsolidation, and extinction of standard "delay" fear conditioning, in which awareness is not required for learning. Far less is understood about the neural circuit supporting more complex, explicit associations. "Trace" fear conditioning is considered to be a rodent model of explicit fear because it relies on the cortex and hippocampus and requires explicit contingency awareness in humans for successful acquisition. In the current set of studies, we aimed to better characterize the neural circuit supporting the consolidation, reconsolidation, and extinction of trace fear in order to better …
The Role Of Nmda Receptors In Extinction Of Cocaine Self-Administration, Madalyn Hafenbreidel
The Role Of Nmda Receptors In Extinction Of Cocaine Self-Administration, Madalyn Hafenbreidel
Theses and Dissertations
Relapse is highly prevalent among recovering addicts, and can be triggered by associations made between the rewarding effects of the drug and cues, such as drug paraphernalia or contexts. Inhibiting these associations, through new extinction learning, could help reduce relapse rates. Extinction is formed in phases, like other types of memory. The memory first is acquired in short-term memory, then is consolidated into long-term storage from which it can be retrieved at a later time (Quirk & Mueller, 2008). NMDA receptors are necessary for extinction in other paradigms (Santini, Muller, & Quirk, 2001), and we previously found that blocking NMDA …