Adolescent Peer Acceptance: An fMRI and Ecological Momentary Assessment Study

Mary Pereira Ryan

Advisor: Tara Chaplin, PhD, Department of Psychology

Committee Members: Sarah Fischer, Tim Curby

Online Location, https://zoom.us/j/9387717508
May 07, 2025, 10:30 AM to 12:30 PM

Abstract:

Adolescence is a period of heightened sensitivity to social reward and peer acceptance. This increase may be due to the developmental changes that occur in the brain during this stage, including rapid changes in reward processing (e.g., striatum, amygdala) and social processing brain regions (e.g., dmPFC, superior temporal gyrus). Because of these developmental changes, peer acceptance can be important for protecting adolescents from depressive symptoms. Some initial fMRI studies have examined the neural basis for the association between lower peer acceptance and depressive symptoms finding that adolescent adolescents with symptoms showed greater TPJ and anterior insula activation during a peer acceptance task versus healthy controls. While some studies have examined this association, more work is needed in this area. Additionally, this prior work has largely been in the lab or scanner and thus has not examined real-world momentary associations between peer acceptance and negative emotions related to depression. This dissertation addressed these gaps in the literature with the following studies: 

Study 1 investigated the association between neural responses to peer acceptance and depressive symptoms in early adolescence. Using functional magnetic resonance imaging (fMRI), I examined neural activation in key reward and salience processing regions—ventral striatum (VS), anterior insula (AI), anterior cingulate cortex (ACC), and temporoparietal junction (TPJ)—in a sample of 163 adolescents (ages 11–14). I tested whether neural responses to peer acceptance were associated with baseline depressive symptoms and whether they predicted depressive symptom trajectories over a two-year period. Results indicated that lower ACC activation during peer acceptance was associated with higher depressive symptoms at baseline, suggesting that blunted salience processing of social rewards may have contributed to adolescent depression. However, neural responses to peer acceptance did not predict changes in depressive symptoms longitudinally. These findings highlighted the importance of the ACC in the neural processing of peer social reward and its potential role in adolescent depression.

Study 2 added ecological momentary assessment (EMA) to a sub-sample of 96 youth from the Paper 1 study. EMA is a survey method that involves repeatedly collecting data on an individual’s current thoughts, emotions, and behaviors in real-time, within their natural environment, making it a suitable methodology to examine real-world associations between adolescent emotions and peer acceptance. This study integrated functional Magnetic Resonance Imaging (fMRI) and ecological momentary assessment (EMA) to examine these associations in 72 adolescents (ages 14–17) over 28 days. Results showed that peer acceptance predicted higher positive emotions and lower negative emotions at the same time point. Greater right anterior cingulate cortex (ACC) activation enhanced the positive emotional impact of peer acceptance, and while greater left temporoparietal junction (lTPJ) and anterior cingulate cortex (ACC) activation dampened it. Additionally, no neural moderators emerged for negative emotions. These findings suggested that neural sensitivity to social reward influenced how adolescents emotionally responded to peer acceptance in daily life and may inform future research supporting adolescent mental health. These studies may also inform interventions aimed at promoting adolescent mental health by identifying neural and momentary emotional processes that contribute to resilience or risk for depression.