Contrasting chronic with episodic depression: an analysis of distorted socio-emotional information processing in chronic depression.

BACKGROUND

The specific features that differentiate chronic and episodic depression are widely unknown. This study compares the chronic and episodic form of depression with regard to two domains of socio-emotional information processing: Decoding of other people's emotional states (Theory of Mind) and the perception of own emotions (alexithymia).

METHOD: This study compares 30 chronically and 29 episodically depressed patients by tapping into Theory of Mind deficits with a multi-method approach and by assessing alexithymic deficits. Furthermore, a retrospective assessment of adverse relational childhood experiences is administered.

RESULTS

The observed results reveal distorted information processing in only one of the two domains: Chronically depressed patients scored higher in alexithymia than episodically depressed patients, while no group differences in the domain of Theory of Mind were found. Moreover, alexithymia was found to mediate the influence of adverse relational childhood experiences on depression type (chronic vs. episodic).

LIMITATIONS: Due to the reliance on retrospective and self-report data, results should be interpreted with due caution. In addition, the cross-sectional design limits causal conclusions.

CONCLUSIONS

These results suggest a potentially central role of the deficient perception of own emotions in causing or maintaining chronic depression. Derived practical implications include a focus on the perception of own emotions in the psychotherapy of chronic depression. If future research continues to uncover systematic differences in the psychopathology of chronic and episodic depression, chronicity should be more strongly considered when classifying unipolar depressive disorders.