The effects of reward and frustration in patients with bipolar disorder: Evidence from a computerized task with non-contingent feedback.

BACKGROUND: Bipolar disorder (BD) is characterized by mood changes that implies alterations in reward sensitivity and frustration tolerance. This study examined the effects of monetary reward and frustration on attentional performance and on affective experience across mood states in BD. METHODS: An Affective Posner Task in which the nature of contingencies are divided in the three successive blocks (baseline condition, monetary reward and non-contingent feedback) was applied to BD individuals in their different episodes: mania (n = 30), depression (n = 30), and euthymia (n =  30) as well as to a group of healthy controls (n = 30). RESULTS: Monetary reward improved performance (in terms of faster response times) in the euthymic group and the control group, whereas it impaired performance in the manic group and has not significant effect in the depressed group. In addition, an increased interference of frustration on response accuracy was exhibited in the three groups of BD patients (including euthymia) compared with healthy controls. LIMITATIONS: Participants' affective experience was self-informed by a Likert scale, so the reliability of this measure can be undermined in symptomatic patients in terms of stability and objectivity. Although it was statistically controlled, at the time of testing, all BD patients were medicated. CONCLUSIONS: A dissociated effect of reward and frustration was found between symptomatic and euthymic states in BD: whereas the benefit from monetary reward is affected only during symptomatic episodes (i.e., a state), the notably increased interference of frustration is exhibited also during euthymia (i.e., a trait).