Depression and self-knowledge : behavioral and brain responses of reflected self-evaluation and implicit self-esteem in sub-clinical depression
Year: 2023
Type: dissertation
Abstract: Depression often involves negative self-knowledge, with individuals viewing themselves in a distorted, negative way. The neurobiological mechanism underlying this phenomenon is not yet fully understood. This dissertation consists of three individual studies that investigate behavioral and brain responses of negative self-knowledge in depression. Study I reviewed existing studies and found that, for depressed individuals, negative self-knowledge has been associated with enhanced responses at late positive components and altered activity in cortical midline structures during negative biased direct self-evaluation, where individuals evaluate the self through their own perspective. Study II investigated brain activity of reflected self-evaluation, where individuals evaluate the self through another person’s perspective, in participants with enhanced depressive symptoms (labeled as a dysphoric group). The functional magnetic resonance images were scanned while the participants were evaluating themselves according to others’ opinions. Compared to a control group, the dysphoric group exhibited negative bias in behavioral ratings and altered brain activity in the bilateral tempo-parietal junction during the reflected self-evaluation. Study III investigated brain responses of depression-related low self-esteem, which is considered a consequence of the negative self-evaluation, in both a dysphoric group and a control group. The electroencephalogram was recorded during an implicit association task measuring implicit self-esteem. The results showed that, contrary to the control group, the dysphoric group exhibited an enhanced late positive brain response when the self was unconsciously associated with negative personality traits, compared to when the self was associated with positive personality traits, within the time window of 400–1,000 ms post-stimulus latency. The results suggest a facilitated self-is-negative association, reflecting low implicit self-esteem, in sub-clinical depression. Overall, this dissertation extends our understanding of Beck’s cognitive theory of depression by providing behavioral and neuroimaging evidence for the negative reflected self-evaluation and the low implicit self-esteem related to depression. It also suggests that the self-negativity bias does not occur only in clinical depression, but also in sub-clinical populations with enhanced depressive symptoms.
Author: Lou, Yixue
Institution: University of Jyväskylä
Language: English
Subfield: Experimental and Cognitive Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W7018306374