Bora E - This systematic review was performed to investigate the potential distinctive neuropsychological features of clinical subgroups of bipolar disorder (BD). History of psychosis and full-manic episode were modestly correlated with increased cognitive deficits in BD. Between clinical subtypes of BD, neurocognitive differences were quite subtle and were not distinctive. Other factors reflecting differences in illness severity could also explain observed between-group differences. Most of the cognitive heterogeneity in BD could not be explained by proposed subtypes of BD.