Impaired emotion processing in remitted patients with bipolar disorder

In the present study, we examined whether there is an impairment in affect matching abilities in remitted patients with bipolar disorder and if this could be attributed to problems with facial perception per se and/or the ability to perceive the relative valence of facial expressions indicating emotions. We examined 19 patients with bipolar disorder I, currently remitted, and 30 healthy controls (15 men), matched on age, education, and gender, using two computerized tests: matching facial identity [Kinney's Identity Matching Test (KIMT)] and matching facial emotional expressions [Kinney's Affect Matching Test (KAMT)]. Patients with bipolar disorder performed significantly worse than the healthy group on the KAMT, but not on the KIMT. Performance on the KAMT and KIMT did not correlate with age of onset and duration of illness, or with manic or depressive residual symptoms. The present findings support the differential deficit hypothesis regarding impaired affect perception in bipolar disorder during remission. Patients' deficits were restricted to the matching of facial emotional expressions despite their intact perception of facial identity.