Neurocognitive normality in schizophrenia revisited

Publication date: Available online 19 November 2015 Source:Schizophrenia Research: Cognition Author(s): R. Walter Heinrichs, Farena Pinnock, Eva Muharib, Leah Hartman, Joel Goldberg, Stephanie McDermid Vaz The validity and significance of normal range neurocognition in schizophrenia remain unclear and controversial. We assessed whether normal range patients and controls demonstrate evidence of decline relative to premorbid ability and differ in performance profiles across measures, including those external to the normality criterion. In addition, we compared below normal range healthy control participants with patients at the same ability level. Performance normality was defined as a MATRICS Consensus Cognitive Battery (MCCB) composite T score between 40 and 60. Patients (n=17) and controls (n=24) meeting the criterion were compared on MCCB domain scores and on independent measures of reading ability, probabilistic and social reasoning. Patients (n=19) and controls (n=20) scoring below 40 on the MCCB composite were compared on the same set of measures. Cognitively normal range patients and controls did not differ on estimated premorbid ability or decline and differed only on the Processing Speed domain of the MCCB. Performance did not differ across other domains or on social and probabilistic reasoning tasks. Cognitively below normal range patients and controls showed marked discrepancies between premorbid and current ability, but there were no group differenc...
Source: Schizophrenia Research: Cognition - Category: Psychiatry Source Type: research