Meta-analysis of 41 Functional Neuroimaging Studies of Executive Function in Schizophrenia

Abstract

Impaired cognition is a core, disabling feature of schizophrenia, with no established treatment. Although numerous deficits have been described across perceptual, attentional, mnemonic, linguistic, and intellectual functions, impaired executive functions are among the most widely observed, and they are consistently associated with impaired function of the prefrontal cortex (PFC).¹ Different aspects of executive dysfunction have been examined, including multiple facets of working memory, response inhibition, conflict processing, and problem solving, demonstrating deficits across a range of circumscribed PFC regions, such as the ventrolateral PFC (VLPFC), dorsolateral PFC (DLPFC), ventromedial PFC, and anterior cingulate cortex (ACC). A recent quantitative meta-analysis of 12 N-back studies found alterations among schizophrenic subjects compared with healthy controls in several nodes of this neural network, including reduced activity in the DLPFC and increased activity in the VLPFC, ACC, and left frontal pole.² Other studies have reported reduced activity in the VLPFC during other working memory tasks³ and in the ACC during conflict processing.^4,5