Basic Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Psychiatr. Dec 19, 2021; 11(12): 1274-1287
Published online Dec 19, 2021. doi: 10.5498/wjp.v11.i12.1274
Differential aberrant connectivity of precuneus and anterior insula may underpin the diagnosis of schizophrenia and mood disorders
Katrin Aryutova, Rositsa Paunova, Sevdalina Kandilarova, Kristina Stoyanova, Michael HJ Maes, Drozdstoy Stoyanov
Katrin Aryutova, Sevdalina Kandilarova, Drozdstoy Stoyanov, Psychiatry and Medical Psychology, Medical University, Plovdiv 4002, Bulgaria
Rositsa Paunova, Kristina Stoyanova, Michael HJ Maes, Research Institute, Medical University, Plovdiv 4002, Bulgaria
Author contributions: Kandilarova S and Stoyanov D designed and coordinated the study; Kandilarova S, Aryutova K, Paunova R and Stoyanova K performed the experiments; Kandilarova S and Paunova R acquired and analyzed the data; Aryutova K and Paunova R interpreted the data; Aryutova K wrote the original draft; Aryutova K prepared the visualization; Maes MH, Kandilarova S and Stoyanov D reviewed and edited the original draft; all authors approved the final version of the article.
Institutional review board statement: The Ethics Committee at Medical University of Plovdiv has approved the protocol of the study on 29 May 2015 (ID: P-369/29.05.2015).
Informed consent statement: The informed consent statement was waived.
Conflict-of-interest statement: Authors declare no conflict of interest.
Data sharing statement: Data are available to share on demand.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed following the Creative Commons Attribution-NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Drozdstoy Stoyanov, DSc, PhD, Professor, Psychiatry and Medical Psychology, Medical University, Vassil Aprilov 15 a, Plovdiv 4002, Bulgaria. drozdstoy.stoyanov@mu-plovdiv.bg
Received: April 14, 2021
Peer-review started: April 14, 2021
First decision: June 5, 2021
Revised: June 15, 2021
Accepted: August 31, 2021
Article in press: August 31, 2021
Published online: December 19, 2021
Processing time: 244 Days and 19.4 Hours
Abstract
BACKGROUND

Over the past decade, resting-state functional magnetic resonance imaging (rs-fMRI) has concentrated on brain networks such as the default mode network (DMN), the salience network (SN), and the central executive network (CEN), allowing for a better understanding of cognitive deficits observed in mental disorders, as well as other characteristic psychopathological phenomena such as thought and behavior disorganization.

AIM

To investigate differential patterns of effective connectivity across distributed brain networks involved in schizophrenia (SCH) and mood disorders.

METHODS

The sample comprised 58 patients with either paranoid syndrome in the context of SCH (n = 26) or depressive syndrome (Ds) (n = 32), in the context of major depressive disorder or bipolar disorder. The methods used include rs-fMRI and subsequent dynamic causal modeling to determine the direction and strength of connections to and from various nodes in the DMN, SN and CEN.

RESULTS

A significant excitatory connection from the dorsal anterior cingulate cortex to the anterior insula (aI) was observed in the SCH patient group, whereas inhibitory connections from the precuneus to the ventrolateral prefrontal cortex and from the aI to the precuneus were observed in the Ds group.

CONCLUSION

The results delineate specific patterns associated with SCH and Ds and offer a better explanation of the underlying mechanisms of these disorders, and inform differential diagnosis and precise treatment targeting.

Keywords: Schizophrenia, Major depressive disorder, Bipolar disorder, Resting-state functional magnetic resonance imaging, effective connectivity, precuneus, insula, default mode network, salience network

Core Tip: The present study reports a significant excitatory connection from the anterior cingulate cortex to the anterior insula (aI) that was observed in the schizophrenia patient group, whereas inhibitory connections from the precuneus (Pc) to the ventrolateral prefrontal cortex and from aI to Pc were observed in the major depressive episode group. The results delineate specific aberration patterns which correspond to the clinical presentations of the nosological units and can further contribute to a better explanation of the underlying mechanisms of these disorders as well as to inform differential diagnosis and precise treatment targeting.