Suppression and acceptance in unipolar depression: Short-term and long-term effects on emotional responding.

OBJECTIVES: Transdiagnostic treatments increasingly include emotion regulation training focused on use of emotional suppression and acceptance. Despite the frequent use of these treatments in depression, little is known about the effects of these strategies in this population. DESIGN: An experimental study. METHODS: Eighty Veterans with unipolar depression participated in a study examining effects of these strategies on emotional responding (subjective, behavioural, and physiological). Physiological measures included: heart rate (HR), respiration (Resp), skin conductance (SC), and corrugator electromyography. On Day 1, participants were randomised to one of three conditions (acceptance, suppression, or control) and underwent an autobiographical sad mood induction. On Day 2, participants underwent a similar mood induction one week later. RESULTS: The suppression group demonstrated reduced physiological reactivity (Resp and SC) on Day 1. However, the suppression group reported decreased positive affect on Day 2. CONCLUSIONS: Results support short-term effectiveness and longer term costs from suppression use among depressed individuals. Findings may inform application of transdiagnostic emotion regulation treatments and suggest suppression functions differently in depressed versus other clinical populations.