Correlation between neuropsychological and social cognition measures and symptom dimensions in schizophrenic patients

Neurocognitive and social cognition deficits have been largely reported in Schizophrenia (SKZ) but their association with psychopathology remains uncertain. Our purpose was to explore the relationship between symptom dimensions and neuropsychological performances. We enrolled 35 stabilized schizophrenic outpatients of the Department of Psychiatry of Policlinico Hospital, University of Milan, who completed psychiatric Rating Scales, the Brief Assessment of Cognition in Schizophrenia (BACS) and the Executive and Social Cognition Battery (ESCB). Disorganized dimension seems to have the most significant impact on cognition, being associated with performance in several BACS subtests (verbal memory, working memory, motor speed, symbol coding, Tower of London) and ESCB tasks (MET and Hotel task number of tasks attempted, number of broken MET rules, sum of deviations in Hotel Task). Positive dimension correlated with performance in verbal fluency, negative dimension with IOWA Test results, cognitive dimension with MET number of inefficiencies and Eyes test score. Impulsive-aggressive and depressive dimensions weakly correlated only with Faux Pas test. Our study supports the existence of a specific disorganized dimension in SKZ, separated from cognitive dimension evaluated through clinical instruments (e.g. PANSS), but capable of influencing cognitive abilities. Furthermore, it strengthens the validity of ecological tasks in evaluating cognition in SKZ.