The present study aimed to: (1) Characterize markers of reward sensitivity during periods of social stress using a well validated social feedback paradigm; (2) Evaluate clinical relations between reward markers and anhedonia; and (3) Investigate if elevated levels of baseline prior exposure to stress (i.e., peer victimization) are associated with the degree of ventral striatum suppression and anhedonia symptoms in a social stress context. A total of 29 adolescents between the ages of 13 and 17 years old (Mage = 15.31; SD = 1.51; 55.2% cisgender girls) participated in the present study. Participants were asked to complete a semi-structured interview; fill out self-report questionnaires regarding social anxiety, stress, depression, and anhedonia; and complete a magnetic resonance imaging scan while playing the Island Getaway task. Ventral striatum (VS) BOLD signal activation estimates were then extracted during discrete phases of the game (e.g., anticipation of social feedback and outcome of social feedback) and statistically compared within-subjects via paired samples t-tests and correlated to social anxiety measures. Additionally, regression analyses assessed the effect of VS activation on anhedonia as well as the associative effect of peer victimization on VS activation and anhedonia. Results revealed that when in the presence of social stress (defined as the potential for negative feedback), socially anxious adolescents demonstrated significantly suppressed VS activation relative to baseline when anticipating feedback. Additionally, results indicated that the degree of reduced VS activation during anticipation was correlated to total changes in anhedonia severity across the task. Lastly, results demonstrated that overt peer victimization is a significant predictor of suppressed VS activation during anticipation of social feedback, but not during social outcomes. Taken together, these results identify potentially novel mechanisms associated with anhedonia and blunted reward processing in socially anxious youth that could be improved via interventions that target positive-valence systems. / Doctor of Philosophy / Socially anxious teens may be at a heightened risk for developing anhedonia – which means that they are showing a significant lack of interest in things they used to find interesting or rewarding. This is problematic, because the presence of anhedonia is associated with not doing as well in therapy and even with higher rates of suicide attempt. One area that may be linked to the development of anhedonia in socially anxious teens is social stress induced disrupted reward processing in certain regions of the brain that generally activate when people anticipate a reward. Despite this, there is very little research on the development of anhedonia is socially anxious teens and even less that focuses on biological and behavioral experiences of reward processing when under social stress. This study examines this potential stress-to-anhedonia pipeline by looking at a key region of the brain, called the ventral striatum, to see if social stress does disrupt reward processing in socially anxious teens, and, if so, if this disrupted reward processing is related to anhedonia. Through evaluating a total of 29 socially anxious teens who underwent a social stress task while completing brain scanning, the present study demonstrated evidence for diminished brain activation in the ventral striatum when anticipating rewards. Additionally, the present study showed that reduced brain activation in the ventral striatum was associated with changes in anhedonia severity. Lastly, results from this study indicated that peer victimization (or bullying) was a significant predictor of diminished brain activation in the ventral striatum. Taken together, these results identify potentially new markers associated with anhedonia and blunted reward processing in socially anxious youth that could be improved via interventions.
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/114949 |
| Date | 05 May 2023 |
| Creators | Carlton-Smith, Corinne Nicole |
| Contributors | Psychology, Richey, John Anthony, Kim-Spoon, Jungmeen, Ollendick, Thomas H., Boljonis, Rosanna Breaux |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Dissertation |
| Format | ETD, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
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