Reduced functional connectivity during controlled semantic integration in schizophrenia: A multivariate approach

• Published in: Human brain mapping Vol. 36; no. 8; pp. 2948 - 2964
• Main Authors: Woodward, Todd S., Tipper, Christine M., Leung, Alexander L., Lavigne, Katie M., Sanford, Nicole, Metzak, Paul D.
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.08.2015; John Wiley & Sons, Inc; John Wiley and Sons Inc
• Subjects: Adult; Brain - physiopathology; Brain Mapping - methods; constrained principal component analysis; Female; functional connectivity; functional magnetic resonance imaging; Humans; Language Tests; Magnetic Resonance Imaging - methods; Male; Multivariate Analysis; Neural Pathways - physiopathology; Neuropsychological Tests; Pattern Recognition, Visual - physiology; Psychotic Disorders - physiopathology; Reaction Time; Reading; schizophrenia; Schizophrenia - physiopathology; semantic association; semantic distance; semantic integration; Semantics; Signal Processing, Computer-Assisted; functional connectivity; semantic association; schizophrenia; functional magnetic resonance imaging; semantic integration; constrained principal component analysis; semantic distance
• ISSN: 1065-9471; 1097-0193
• DOI: 10.1002/hbm.22820

Impairment in controlled semantic association is a central feature of schizophrenia, and the goal of the current functional magnetic resonance imaging study was to identify the neural correlates of this impairment. Thirty people with schizophrenia and 30 healthy age‐ and gender‐matched control subjects performed a task requiring participants to match word pairs that varied in semantic distance (distant vs. close). A whole‐brain multivariate connectivity analysis revealed three functional brain networks of primary interest engaged by the task: two configurations of a multiple demands network, in which brain activity did not differ between groups, and a semantic integration network, in which coordinated activity was reduced in schizophrenia patients relative to healthy controls, for distantly relative to closely related word pairs. The hypoactivity during controlled semantic integration in schizophrenia reported here, combined with hyperactivity in automatic semantic association reported in the literature, suggests an imbalance between controlled integration and automatic association. This provides a biological basis for Bleuler's concept of schizophrenia as a “split mind” arising from an impaired ability to form coherent associations between semantic concepts. Hum Brain Mapp 36:2948–2964, 2015. © 2015 Wiley Periodicals, Inc.