Network modeling of resting state connectivity points towards the bottom up theories of schizophrenia. (30th August 2017)

• Record Type: Journal Article
• Authors: Orliac, François; Delamillieure, Pascal; Delcroix, Nicolas; Naveau, Mikael; Brazo, Perrine; Razafimandimby, Annick; Dollfus, Sonia; Joliot, Marc
• Is Part Of: Psychiatry research. Volume 266(2017)
• Page Start: 19
• Page End: 26
• Publication Date: 2017-08-30
• Subjects: AH Auditory Hallucinations in medical history -- ANCOVA Analysis Of COVAriance -- ANOVA ANalysis Of Variance -- AVH Auditory and Visual Hallucinations in medical history -- BNFC Between-Network Functional Connectivity -- C-FD Cumulated Framewise Displacement -- Cpz-eq average Chlorpromazine equivalent -- DMN Default-Mode Network -- FC Functional Connectivity -- FD Framewise Displacement -- HC Healthy Controls -- ICA Independent Component Analysis -- MANOVA Multivariate ANalysis Of Variance -- MICCA Multi-scale Individual Component Clustering Analysis -- MINI Mini International Neuropsychiatric Interview -- MRI Magnetic Resonance Imaging -- NBS Network-Based Statistics -- NH No Hallucinations in medical history -- PANSS Positive And Negative Syndrome Scale -- PANSS-N Negative symptoms subscale of the PANSS -- PANSS-P Positive symptoms subscale of the PANSS -- RN Resting-state Network -- PS Patients with Schizophrenia -- WNFC Within-Network Functional Connectivity; Functional magnetic resonance imaging -- Hallucinations -- Neural networks; Psychiatry -- Periodicals; Brain -- Imaging -- Periodicals; Psychiatry -- Periodicals; Diagnostic Imaging -- Periodicals; Psychiatrie -- Périodiques; Cerveau -- Imagerie pour le diagnostic -- Périodiques; 616.890754
• DOI: 10.1016/j.pscychresns.2017.04.003
• Languages: English
• ISSNs: 0925-4927

Abstract

Abstract: The dysconnectivity theory of schizophrenia proposes that schizophrenia symptoms arise from abnormalities in neuronal synchrony. Resting-state Functional Connectivity (FC) techniques allow us to highlight synchronization of large-scale networks, the Resting-state Networks (RNs). A large body of work suggests that disruption of RN synchronization could give rise to specific schizophrenia symptoms. The present study aimed to explore within- and between-network FC strength of 34 RNs in 29 patients suffering from schizophrenia, and their relationships with schizophrenia symptoms. Resting-state data were analyzed using independent component analysis and dual-regression techniques. Our results showed that both within-RN and between-RN FC were disrupted in patients with schizophrenia, with a global trend toward weaker FC. This decrease affected more particularly visual, auditory and crossmodal binding networks. These alterations were correlated with negative symptoms, positive symptoms and hallucinations, indicating abnormalities in visual processing and crossmodal binding in schizophrenia. Moreover, we stressed an anomalous synchronization between a visual network and a network thought to be engaged in mental imaging processes, correlated with delusions and hallucinations. Altogether, our results supported the assumption that some schizophrenia symptoms may be related to low-order sensory alterations impacting higher-order cognitive processes, i.e. the "bottom-up" hypothesis of schizophrenia symptoms. Highlights: Resting-state networks allow to explore brain organization in schizophrenia. Both within and between network connectivity are disrupted in schizophrenia. Visual, auditory and crossmodal binding networks seem more particularly affected. Impairments in basic perceptual processes may impact higher-order processes. Confusion between mental imagery and external stimuli may result in hallucinations.