Reality monitoring and paranoia in remitted delusional depression

Object: Is delusional depression a more severe form of mood disorder, or psychoticism should be considered an indi-vidual characteristic associated with affective illness?Recent studies supported the hypothesis that patients affected by psychiatric disorders with psychotic symptoms havespecific abnormalities of reality testing of ongoing perception, which become evident with source monitoring tasks. The aimof this work is to study neuropsychological correlate (source monitoring task) of psychosis in euthymic mood disorderedpatients with or without psychotic features.Method: Fifty-nine patients in stable euthymic conditions were studied, 33 with a DSM-IV diagnosis of Bipolar Disor-der and 26 with a DSM-IV diagnosis of Major Depressive Disorder. Psychopathological assessment included measures ofparanoia (FVPS, IPSAQ), social adjustment (SASS), and depressive dysfunctional cognitions (CQ). Reality monitoringtasks performance were evaluated with the Source Monitoring Task (Keefe 2002) and were analysed with signal detectionanalysis.Results: Patients with a remitted major depressive episode with psychotic features used more lax criteria in evaluatingself generated, but not perceived stimuli in respect to patients who did not show psychotic features.Conclusions: Our findings support the hypothesis of selective biases in reality monitoring as neuropsychological corre-lates of psychosis