Self-esteem, cortisol reactivity, and depressed mood mediated by perceptions of control.

This study investigated cortisol reactivity (CR) as a moderator and perceptions of control as a mediator between low self-esteem (SE) and depressed mood. Fifty-four participants completed SE and mood inventories before an uncontrollable laboratory stressor. Salivary cortisol was determined before and after the stressor. Analyses indicated significance for SE (beta=-0.30), CR (beta=-0.92) and their interaction (beta=-0.90) in predicting depressed mood (P=0.03 for all). Low SE and decreased CR predicted the highest levels of depressed mood. The interaction indicated that depressed mood was predicted by increases in cortisol in individuals with higher SE, but by decreases in cortisol in individuals with lower SE. These relationships were statistically explained by low perceptions of control at baseline. Findings support biopsychological explanations for depression, with SE, CR, and uncontrollability as putative markers of depressed mood that may be even more pronounced in depressive disorders.