Altered Effective Connectivity in the Default Network of the Brains of First-Episode, Drug-Naïve Schizophrenia Patients With Auditory Verbal Hallucinations.
Zhiyong Zhao, Xuzhou Li, Guoxun Feng, Zhe Shen, Shangda Li, Yi Xu, Manli Huang, Dongrong Xu
Frontiers in Human Neuroscience 2018 DOI: 10.3389/fnhum.2018.00456 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Case-control study Peer reviewed |
|---|---|
| Sample size | 86 |
| Population | First-episode, drug-naïve schizophrenia patients with auditory verbal hallucinations (n=28), schizophrenia patients without auditory verbal hallucinations (n=20), and healthy controls (n=38) |
| Topics | Default mode network |
| Keywords | Granger causality analysis Auditory verbal hallucinations Effective connectivity Schizophrenia |
| Key findings | Compared with schizophrenia patients without auditory verbal hallucinations, those with hallucinations showed decreased effective connectivity from the anteromedial prefrontal cortex to the left inferior temporal gyrus and from the posterior cingulate cortex to the left cerebellum posterior lobe, left inferior temporal gyrus, and right middle frontal gyrus. Connectivity strengths correlated with clinical assessments, and these connectivities showed diagnostic value in distinguishing the two patient groups. The authors suggest the left inferior temporal gyrus may be a potential biomarker for hallucinations in schizophrenia. |
Abstract
Although the default mode network (DMN) is known to be abnormal in schizophrenia (SZ) patients with auditory verbal hallucinations (AVHs), it is still unclear whether AVHs that occur in SZ are associated with certain information flow in the DMN. This study collected resting-state functional magnetic resonance imaging data from 28 first-episode, drug-naïve SZ patients with AVHs, 20 SZ patients without AVHs, and 38 healthy controls. We used Granger causality analysis (GCA) to examine effective connectivity (EC) of two hub regions [posterior cingulate cortex (PCC) and anteromedial prefrontal cortex (aMPFC)] within the DMN. We used two-sample t-tests to compare the difference in EC between the two patient groups, and used Spearman correlation analysis to characterize the relationship between imaging findings and clinical assessments. The GCA revealed that, compared with the non-AVHs group, EC decreased from aMPFC to left inferior temporal gyrus (ITG) and from PCC to left cerebellum posterior lobe, ITG, and right middle frontal gyrus in SZ patients with AVHs. We also found significant correlations between clinical assessments and mean strengths of connectivity from aMPFC to left ITG and from PCC to left ITG. Moreover, receiver operating characteristic analysis revealed that the above-mentioned effective connectivities had a diagnostic value for distinguishing SZ patients with AVHs from non-AVHs patients. These findings suggest that AVHs in SZ patients may be associated with the aberrant information flows of the DMN, and the left ITG may probably serve as a potential biomarker for the neural mechanisms underlying AVHs in SZ patients.
Comparable studies
Other observational and cohort studies on default mode network, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| A default mode of brain function Normal adult human brain | 2001 | Observational study | |
| Resting-State Functional Connectivity Reflects Structural Connectivity in the Default Mode Network Healthy subjects | 2008 | Observational cohort | |
| Meditation experience is associated with increased cortical thickness Participants with extensive Insight meditation experience and matched controls | 2005 | Observational cohort | n = 20 |
| Meditation experience is associated with differences in default mode network activity and connectivity Experienced meditators and matched meditation-naive controls | 2011 | Observational cohort | |
| The precuneus/posterior cingulate cortex plays a pivotal role in the default mode network: Evidence from a partial correlation network analysis Healthy subjects | 2008 | Observational study |
Citations in the library
Cites 5
- Effects of model-based physiological noise correction on default mode network anti-correlations and correlations Neuroimage May 15, 2009
- The Neurodynamic Organization of Modality-Dependent Hallucinations Cerebral Cortex April 24, 2012
- Dysconnectivity of multiple resting-state networks in patients with schizophrenia who have persistent auditory verbal hallucinations Journal of Psychiatry and Neuroscience October 20, 2011
- Auditory Hallucinations and the Brain’s Resting-State Networks: Findings and Methodological Observations Schizophrenia Bulletin June 8, 2016
- The Computational Anatomy of Psychosis Frontiers in Psychiatry April 25, 2013