Campell-Sills, Barlow, Brown, Hofmann (2006).

The present investigation compared the subjective and physiological effects of emotional suppression and acceptance in a sample of individuals with anxiety and mood disorders. Sixty participants diagnosed with anxiety and mood disorders were randomly assigned to one of two groups. One group listened to a rationale for suppressing emotions, and the other group listened to a rationale for accepting emotions. Participants then watched an emotion-provoking film and applied the instructions. Subjective distress, heart rate, skin conductance level, and respiratory sinus arrhythmia were measured before, during, and after the film. Although both groups reported similar levels of subjective distress during the film, the acceptance group displayed less negative affect during the post-film recovery period. Furthermore, the suppression group showed increased heart rate and the acceptance group decreased heart rate in response to the film. There were no differences between the two groups in skin conductance or respiratory sinus arrhythmia. These findings are discussed in the context of the existing body of research on emotion regulation and current treatment approaches for anxiety and mood disorders.