Background: Though characteristics of emotional processing in patients with bipolar disorder have been less explored, deficits in emotional regulation are thought to be a core feature of bipolar disorder. We hypothesized that patients with bipolar depression would demonstrate emotional biases and their emotional responsiveness would be related to an ability to cope and adapt.
Methods: Seventeen patients with bipolar depression and 15 healthy controls completed Conner-Davidson Resilience Scale (CD-RISC). Subjects rated pictures of the International Affective Picture System that priorly had been selected by investigators along the 3 dimensions of pleasure, arousal and dominance on the Self-Assessment of Manikin scale.
Results: The patients had a significantly lower CD-RISC score than controls. Pictures with positive valence were rated as less pleasant and less arousal in patients than in controls. Emotionally neutral pictures, on the other hand, were rated as more arousing in patients than in controls. The mean score of pleasure and arousal ratings for negative emotional stimuli was not different between the two groups. In the patients group, the severities of depressive symptoms were significantly correlated with the pleasure scores of neutral stimuli, and the CD-RISC scores were significantly correlated with the arousal scores of positive stimuli and pleasure scores of neutral stimuli.
Conclusions: The current findings suggest decreased sensitivity to emotionally positive stimuli and increased sensitivity to emotionally neutral stimuli in bipolar depression. Given the relationship of those emotional biases with the resilience scores, therapeutic implications of those emotional biases need to be studied further in the future.