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Although depression is characterized by low self-esteem as measured by questionnaires, research using implicit measures of self-esteem has failed to reveal the expected differences between depressed and non-depressed individuals. In this study, we used an implicit measure which enables the differentiation of ideal Self and actual Self-esteem, through the introduction of propositions: "I am" versus "I want to be". We measured implicit relational associations about actual and ideal self in low (N=27) versus high dysphoric (N=29) undergraduates. Our data revealed that dysphoric individuals have a higher ideal-self-esteem, and lower actual selfesteem in comparison to healthy participants. The results underscore the need to go beyond simple associations and suggest that the use of individual-specific propositions could enhance our understanding of the implicit measurement of self-esteem. Furthermore, these results underscore the importance of actual versus ideal self-discrepancy theories, which might guide the content of therapeutic interventions.

A growing body of work suggests that both depressed and non-depressed individuals display implicit positivity towards the self. In the current study, we examined whether this positivity can be underpinned by two qualitatively distinct propositions related to actual (‘I am good’) or ideal (‘I want to be good’) self-esteem. Dysphoric and non-dysphoric participants completed a self-esteem Implicit Association Test (IAT) as well an Implicit Relational Assessment Procedure (IRAP) targeting their actual self-esteem and an IRAP targeting ideal self-esteem. Both groups demonstrated similar and positive IAT effects. A more complex picture emerged with regard to the IRAP effects. Whereas non-dysphorics did not differ in their actual and ideal self-esteem, their dysphoric counterparts demonstrated lower actual than ideal self-esteem. Our results suggest that closer attention to the role of propositional processes in implicit measures may unlock novel insight into the relationship between implicit self-esteem and depression.

Abstract 2Objective: Although left dorsolateral prefrontal cortical (DLPFC) repetitive Transcranial Magnetic Stimulation (rTMS) is used to treat major depression, its underlying neurophysiological working mechanism remains to be determined. Prior research suggested that the clinical effects could be mediated by affecting the hypothalamic-pituitary-adrenal (HPA) system, but experimental studies in healthy individuals did not yield clear results. However, in healthy individuals, the influence of HFrTMS on the HPA-system may only be detected when it is challenged.Methods: In 30 rTMS naïve healthy females we evaluated the effect of one sham-controlled high frequency (HF)-rTMS session applied to the left DLPFC on the stress hormone cortisol by collecting salivary cortisol samples. In order to increase stress levels, five minutes after stimulation, all participants performed the Critical Feedback Task (CFT), during which they were criticized on their performance. To take possible mood influences into account, all participants were also assessed with Visual Analogue Scales (VAS).Results: The experimental procedure did not affect mood differently in the real or sham stimulation.Area under the curve (AUCi) analysis showed that one real HF-rTMS session significantly influenced HPA-system sensitivity, as demonstrated by a decrease in cortisol concentrations. The sham procedure yielded no effects.Conclusions: In line with former observations in major depression, one real left DLPFC HF-rTMS session significantly influenced HPA-system sensitivity in experimentally stressed females, resulting in decreases in cortisol levels.