title: The functional anatomy of schizophrenia: A dynamic causal modeling study of predictive coding.
abstract: This paper tests the hypothesis that patients with schizophrenia have a deficit in selectively attending to predictable events. We used dynamic causal modeling (DCM) of electrophysiological responses - to predictable and unpredictable visual targets - to quantify the effective connectivity within and between cortical sources in the visual hierarchy in 25 schizophrenia patients and 25 age-matched controls. We found evidence for marked differences between normal subjects and schizophrenia patients in the strength of extrinsic backward connections from higher hierarchical levels to lower levels within the visual system. In addition, we show that not only do schizophrenia subjects have abnormal connectivity but also that they fail to adjust or optimize this connectivity when events can be predicted. Thus, the differential intrinsic recurrent connectivity observed during processing of predictable versus unpredictable targets was markedly attenuated in schizophrenia patients compared with controls, suggesting a failure to modulate the sensitivity of neurons responsible for passing sensory information of prediction errors up the visual cortical hierarchy. The findings support the proposed role of abnormal connectivity in the neuropathology and pathophysiology of schizophrenia.
authors.affiliation: Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Israel. Electronic address: nfogelson@gmail.com.
authors.forename: Noa
authors.initials: N
authors.lastname: Fogelson
authors.affiliation: The Wellcome Trust Centre for Neuroimaging, Institute of Neurology, UCL, London, UK.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Litvak
authors.affiliation: Institute for Psychiatric Studies, Sha'ar Menashe Mental Health Center, Hadera, Israel; B Rappaport Faculty of Medicine, Technion, Haifa, Israel.
authors.forename: Avi
authors.initials: A
authors.lastname: Peled
authors.affiliation: Department of Physical Education, University of A Coruña, La Coruña, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Fernandez-del-Olmo
authors.affiliation: The Wellcome Trust Centre for Neuroimaging, Institute of Neurology, UCL, London, UK. Electronic address: k.friston@ucl.ac.uk.
authors.forename: Karl
authors.initials: K
authors.lastname: Friston
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology*; D001499:Bayes Theorem; D001921:Brain / Q000503:physiopathology*; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D009434:Neural Pathways / Q000503:physiopathology; D009474:Neurons / Q000502:physiology; D009483:Neuropsychological Tests; D010775:Photic Stimulation; D012559:Schizophrenia / Q000188:drug therapy / Q000503:physiopathology*; D012815:Signal Processing, Computer-Assisted; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: Connectivity; Dynamic causal modeling; EEG; Prediction; Schizophrenia