How social evaluative feedback shapes beliefs about the self and others: behavioral and neurophysiological studies

Social evaluative feedback plays a central role in shaping one's self-view and impressions of others. It can either confirm or conflict with one’s self-view. When conflicts arise, discrepancies are reduced by updating the self-view or revising beliefs about the sender. Positive and unexpected feedback typically induces positive changes in the self-view, whereas individuals with depressive symptoms show reduced integration of positive information and stronger generalization of negative information. These findings raise questions about how feedback sender characteristics (e.g., relevance, expertise, valence) and individual differences in depressive symptoms influence feedback processing and integration, as well as which neural mechanisms underlie these processes. This dissertation examined how individuals update their beliefs in social evaluative contexts using three electroencephalography (EEG) and behavioral studies. While Study I focused solely on the updating of feedback expectations with clear sender contingencies, Study II concentrated on how feedback alters perceptions of others, and Study III focused on how feedback influences the selfview. It was expected that positive feedback would elicit stronger updates of self-views and expectations in healthy participants, while smaller updates would occur in response to negative feedback or higher depressive symptoms. On a neural level, we expected sender and feedback characteristics to modulate specific event-related potentials (ERPs) of the EEG: the early posterior negativity (EPN), the feedbackrelated negativity (FRN), and the late positive potential (LPP). Study I showed that participants differentiated expectations across senders based on the sender's valence, updating them more strongly for negative ones. Self-relevant feedback enhanced the EPN and LPP, while expectation violations influenced the FRN. Study II demonstrated the rapid adjustment of expectations to sender valence, with positive senders increasing and negative senders decreasing self-view ratings. Expectation violations modulated the FRN, while incongruence with self-view modulated the LPP. The LPP also tracked the magnitude of self-view updating. Study III revealed that depressive symptoms were associated with stronger negative expectations and a reduced positivity bias, especially regarding negative expert feedback and positive peer feedback. The FRN again reflected expectation violations, while the LPP was modulated by incongruence and symptom severity. Overall, the findings indicate that belief updating is influenced by the sender's valence, relevance, and individual characteristics. The FRN and LPP emerged as sensitive neural markers of dynamic belief change, advancing our understanding of social evaluative feedback in healthy and clinical populations.