Self-esteem instability in major depressive disorder: a computational analysis of expectation updating in response to performance feedback.

INTRODUCTION: Major Depressive Disorder (MDD) is consistently associated with low self-esteem; however, how self-evaluative beliefs are updated in response to environmental feedback in MDD remains poorly understood. In this study, we tested the hypothesis that low self-esteem in MDD reflects dynamic instability driven by altered processing of social-evaluative information, rather than a simple static deficit. METHODS: The study enrolled 60 patients with MDD and 30 healthy control participants. All participants completed a Social Comparison-Based Performance Task in which experimentally manipulated positive and negative performance feedback, presented relative to others, was used to modulate perceived social rank. Trial-by-trial changes in performance expectations following feedback were modeled computationally to derive sensitivity coefficients for positive (k_positive) and negative (k_negative) feedback. RESULTS: Relative to healthy controls, the MDD group exhibited significantly lower baseline self-esteem, as measured by the Rosenberg Self-Esteem Scale (RSES), as well as lower initial performance expectations at task onset (p < 0.001). Computational modeling revealed that patients with MDD exhibited significantly greater sensitivity of performance expectation updating to both positive (p < 0.001, r = -0.45) and negative (p < 0.001, r = -0.53) feedback compared with healthy controls. LIMITATIONS: Study limitations include the lack of control for psychotropic medications and the recruitment of a sample restricted to outpatients with moderate symptom severity. CONCLUSIONS: Low self-esteem in MDD is better characterized by instability in self-related belief dynamics rather than a simple static deficit. Therapeutic interventions may therefore benefit from targeting heightened sensitivity to environmental feedback and promoting self-esteem stability, rather than focusing solely on increasing self-esteem levels.