Dynamic Functional Connectivity in Neuropsychiatric Disorders: Methods and Applications

Editorial

20 April 2020

Editorial: Dynamic Functional Connectivity in Neuropsychiatric Disorders: Methods and Applications

Xiaoya Fu

Feng Liu

Zaixu Cui

and

Wenbin Guo

2,803 views

5 citations

Editors

Wenbin Guo

Second Xiangya Hospital, Central South University

Feng Liu

Tianjin Medical University General Hospital

Zaixu Cui

Chinese Institute for Brain Research, Beijing (CIBR)

Impact

Increased CV of dALFF in the left precuneus displayed in coronal (A), sagittal (B), transverse (C), and three-dimensional view (D). Box plots with Whiskers (min–max) show the CV values in the left precuneus of the two groups (E), and scatterplots show the relationship between the CV in the precuneus of the PD group and the disease duration (F). CV, coefficient of variation; dALFF, dynamic spontaneous low-frequency fluctuation.

Original Research

01 October 2019

Dynamic Alterations of Spontaneous Neural Activity in Parkinson's Disease: A Resting-State fMRI Study

Chao Zhang

, 9 more and

Kuncheng Li

Objective: To investigate the dynamic amplitude of low-frequency fluctuations (dALFFs) in patients with Parkinson's disease (PD) and healthy controls (HCs) and further explore whether dALFF can be used to test the feasibility of differentiating PD from HCs.

Methods: Twenty-eight patients with PD and 28 demographically matched HCs underwent resting-state functional magnetic resonance imaging (rs-fMRI) scans and neuropsychological tests. A dynamic method was used to calculate the dALFFs of rs-fMRI data obtained from all subjects. The dALFF alterations were compared between the PD and HC groups, and the correlations between dALFF variability and disease duration/neuropsychological tests were further calculated. Then, the statistical differences in dALFF between both groups were selected as classification features to help distinguish patients with PD from HCs through a linear support vector machine (SVM) classifier. The classifier performance was assessed using a permutation test (repeated 5,000 times).

Results: Significantly increased dALFF was detected in the left precuneus in patients with PD compared to HCs, and dALFF variability in this region was positively correlated with disease duration. Our results show that 80.36% (p < 0.001) subjects were correctly classified based on the SVM classifier by using the leave-one-out cross-validation method.

Conclusion: Patients with PD exhibited abnormal dynamic brain activity in the left precuneus, and the dALFF variability could distinguish PD from HCs with high accuracy. Our results showed novel insights into the pathophysiological mechanisms of PD.

5,619 views

45 citations

Original Research

12 July 2019

Increased Temporal Dynamics of Intrinsic Brain Activity in Sensory and Perceptual Network of Schizophrenia

Youxue Zhang

, 1 more and

Yuan Tian

(A) The preprocessed full-length blood oxygen level-dependent fMRI maps were segmented into several sliding windows (50 TR). Within each window, the fALFF and ReHo were computed for each voxel. The sliding window was systematically shifted by one TR, and the corresponding fALFF and ReHo were computed. Then, the temporal variability of the dynamic fALFF and ReHo were defined as the CV maps across the sliding windows. The pattern of temporal variability of the fALFF (B) and ReHo (C) of the schizophrenic subjects/healthy controls were shown.

Schizophrenic subject is thought as a self-disorder patient related with abnormal brain functional network. It has been hypothesized that self-disorder is associated with the deficient functional integration of multisensory body signals in schizophrenic subjects. To further verify this assumption, 53 chronic schizophrenic subjects and 67 healthy subjects were included in this study and underwent resting-state functional magnetic resonance imaging. The data-driven methods, whole-brain temporal variability of fractional amplitude of low-frequency fluctuations and regional homogeneity (ReHo), were used to investigate dynamic local functional connectivity and dynamic local functional activity changes in schizophrenic subjects. Patients with schizophrenia exhibited increased temporal variability ReHo and fractional amplitude of low-frequency fluctuations across time windows within sensory and perception network (such as occipital gyrus, precentral and postcentral gyri, superior temporal gyrus, and thalamus). Critically, the increased dynamic ReHo of thalamus is significantly correlated with positive and total symptom of schizophrenic subjects. Our findings revealed that deficit in sensory and perception functional networks might contribute to neural physiopathology of self-disorder in schizophrenic subjects.

3,509 views

30 citations

Original Research

02 July 2019

Predicting the Post-therapy Severity Level (UPDRS-III) of Patients With Parkinson's Disease After Drug Therapy by Using the Dynamic Connectivity Efficiency of fMRI

Xuesong Li

, 8 more and

Hua Guo

3,049 views

11 citations

Original Research

12 April 2019

Altered Local and Large-Scale Dynamic Functional Connectivity Variability in Posttraumatic Stress Disorder: A Resting-State fMRI Study

Shishun Fu

, 9 more and

Guihua Jiang

Posttraumatic stress disorder (PTSD) is a psychiatric condition that can emerge after exposure to an exceedingly traumatic event. Previous neuroimaging studies have indicated that PTSD is characterized by aberrant resting-state functional connectivity (FC). However, few existing studies on PTSD have examined dynamic changes in resting-state FC related to network formation, interaction, and dissolution over time. In this study, we compared the dynamic resting-state local and large-scale FC between PTSD patients (n = 22) and healthy controls (HC; n = 22; conducted as standard deviation in resting-state local and large-scale FC over a series of sliding windows). Local dynamic FC was examined by calculating the dynamic regional homogeneity (dReHo), and large-scale dynamic FC (dFC) was investigated between regions with significant dReHo group differences. For the PTSD patients, we also investigated the relationship between symptom severity and dFC/dReHo. Our results showed that PTSD patients were characterized by I) increased dynamic (more variable) dReHo in left precuneus (PCu); II) increased dynamic (more variable) dFC between the left PCu and left insula; and III) decreased dFC between left PCu and left inferior parietal lobe (IPL), and decreased dFC between left PCu and right PCu. However, there is no significant correlation between the clinical indicators and dReHo/dFC after the family-wise-error (FWE) correction. These findings provided the initial evidence that PTSD is characterized by aberrant patterns of fluctuating communication within brain system such as the default mode network (DMN) and among different brain systems such as the salience network and the DMN.

3,938 views

19 citations