Mood-congruent bias and attention shifts in the different episodes of bipolar disorder.

An "affective" go/no-go task was used in the different episodes of bipolar patients (euthymic, depressed, and manic) to examine (1) the presence of a mood-congruent attentional bias; and (2) the patients' ability to inhibit and invert associations between stimuli and responses through blocks. A group of healthy individuals served as controls. Results revealed a mood-congruent attentional bias: patients in the manic episode processed positive information faster, whereas those in the depressive episode processed negative information faster. In contrast, neither euthymic patients nor healthy individuals showed any mood-congruent biases. Furthermore, there was a shift cost across blocks for healthy individuals, but not for the patients. This may reflect a general impairment at selecting relevant information (e.g., in terms of disability to inhibit and invert associations between stimuli and responses) in bipolar participants, regardless of their episode. This state/trait dissociation in an episodic and chronic disorder such as bipolar disorder is important for its appropriate characterisation.