PRESERVED, DETERIORATED AND COMPROMISED IQ TRAJECTORIES IN SCHIZOPHRENIA SPECTRUM DISORDER: FINDINGS FROM A SYSTEMATIC REVIEW

Abstract

Individuals with a schizophrenia spectrum disorder (SSD) are commonly reported to experience intellectual and neurocognitive impairments which may commence prior to the onset of other symptoms. Considerable cognitive heterogeneity is known to exist within the SSD population. Several lines of inquiry have attempted to characterize the variability in IQ trajectory by comparing the relationship between estimates of premorbid and current intellectual function. Three putative IQ trajectories have been consistently identified in the literature: a preserved IQ (PIQ) and compromised IQ (CIQ) trajectory respectively reflective of intact and impaired current intellectual function in the absence of a m..