Cognitive Development in Schizophrenia: Follow-Back from the First Episode

Despite consensus that schizophrenia is a neurodevelopmental disorder characterized by cognitive deficits, objective data documenting the course of cognitive development remain sparse. We conducted a follow-back study of patients ascertained at the time of their initial episode of schizophrenia or schizoaffective disorder, and a group of demographically matched healthy volunteers. We obtained school records containing standardized achievement test scores from the 1st through 12th grades, and scholastic aptitude test results from the 11th and 12th grades, and examined the developmental trajectories of cognitive performance with respect to prospective examinations conducted following participants’ enrollment in our study. We found significant differences in academic achievement tests as early as the first grade, with scores from participants who would later develop schizophrenia lagging behind their peers by 0.8 to 1.1 grade equivalents. This gap widened resulting in a difference between groups of 1.5 to 1....