Are negative symptoms really related to cognition in schizophrenia?

Previous studies have generally found a relationship between negative and cognitive symptoms in schizophrenia. The present study investigated the relationship between the 5 PANSS factors of a recent consensus model developed by NIMH researchers, and cognitive performance as assessed with the MATRICS Consensus Cognitive Battery (MCCB) in 80 patients with schizophrenia using correlation and regression analyses. The PANSS Cognitive factor showed a small to moderate significant association with MCCB Speed of processing, Working memory, Verbal learning, the Neurocognitive composite score, and the Overall composite score. Notably, however, no relationship was found between the PANSS Negative factor and any of the MCCB scores. The Positive, Excited and Depressed factors also did not show associations with the MCCB. These results highlight the need for refined assessment instruments and support the relative independence of cognition from other domains of psychopathology, including negative symptoms, in patients with schizophrenia.