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Background: Uncontrollable body movements are typical symptoms of Parkinson's disease (PD), which results in inconsistent findings regarding resting-state functional connectivity (rsFC) networks, especially for group difference clusters. Systematically identifying the motion-associated data was highly demanded., Purpose: To determine data censoring criteria using a quantitative cross validation-based data censoring (CVDC) method and to improve the detection of rsFC deficits in PD., Study Type: Prospective., Subjects: Forty-one PD patients (68.63 ± 9.17 years, 44% female) and 20 healthy controls (66.83 ± 12.94 years, 55% female)., Field Strength/sequence: 3-T, T1-weighted gradient echo and EPI sequences., Assessment: Clusters with significant differences between groups were found in three visual networks, default network, and right sensorimotor network. Five-fold cross-validation tests were performed using multiple motion exclusion criteria, and the selected criteria were determined based on cluster sizes, significance values, and Dice coefficients among the cross-validation tests. As a reference method, whole brain rsFC comparisons between groups were analyzed using a FMRIB Software Library (FSL) pipeline with default settings., Statistical Tests: Group difference clusters were calculated using nonparametric permutation statistics of FSL-randomize. The family-wise error was corrected. Demographic information was evaluated using independent sample t-tests and Pearson's Chi-squared tests. The level of statistical significance was set at P < 0.05., Results: With the FSL processing pipeline, the mean Dice coefficient of the network clusters was 0.411, indicating a low reproducibility. With the proposed CVDC method, motion exclusion criteria were determined as frame-wise displacement >0.55 mm. Group-difference clusters showed a mean P-value of 0.01 and a 72% higher mean Dice coefficient compared to the FSL pipeline. Furthermore, the CVDC method was capable of detecting subtle rsFC deficits in the medial sensorimotor network and auditory network that were unobservable using the conventional pipeline., Data Conclusion: The CVDC method may provide superior sensitivity and improved reproducibility for detecting rsFC deficits in PD., Level of Evidence: 1 TECHNICAL EFFICACY: Stage 2., (© 2023 International Society for Magnetic Resonance in Medicine.)

Given the rising incidence of stroke, several technology-driven methods for rehabilitation have recently been developed. Virtual reality (VR) is a promising therapeutic technology among them. We recently developed a neuroscientifically grounded VR system to aid recovery of motor function poststroke. The developed system provides unilateral and bilateral upper extremity (UE) training in a fully immersive virtual environment that may stimulate and activate mirror neurons (MNs) in the brain necessary for UE rehabilitation. Twenty-three participants were randomized to a VR group (n = 12) to receive VR intervention (8 h within 2 weeks) plus 8-h occupational therapy (OT) or a control group (n = 11) to receive time-matched OT alone. Treatment effects on motor recovery and cortical reorganization were investigated using the Barthel Index (BI), Fugl-Meyer Upper Extremity (FM-UE), and resting-state fMRI. Both groups significantly improved BI (P < 0.05), reflecting the recovery of UE motor function. The VR group revealed significant improvements on FM-UE scores (P < 0.05) than the control group. Neural activity increased after the intervention, particularly in the brain areas implicating MNs, such as in the primary motor cortex. Overall, results suggested that using a neuroscientifically grounded VR system might offer additional benefits for UE rehabilitation in patients receiving OT., (© 2021 New York Academy of Sciences.)

Virtual reality (VR) is considered to be a promising therapeutic technology for the rehabilitation of upper extremities (UEs) post-stroke. Recently, we designed and then implemented a neuroscientifically grounded VR protocol for the rehabilitation of patients with stroke. The system provides unilateral and bilateral limb mirroring exercises in a fully immersive virtual environment that may stimulate and activate the mirror neuron system in the brain to help patients for their rehabilitation. Twelve patients with subacute stroke underwent the newly implemented VR treatment in addition to conventional rehabilitation for 8 consecutive weekdays. The treatment effect on brain reorganization and motor function was investigated using resting-state fMRI (rs-fMRI) and the Fugl-Meyer assessment for Upper Extremity (FM-UE), respectively. Fifteen healthy controls (HCs) also underwent rs-fMRI scanning one time. The study finally obtained usable data from 8 patients and 13 HCs. After the intervention, patients demonstrated significant improvement in their FM-UE scores (p values < 0.042). Voxel-wise functional connectivity (FC) analysis based on the rs-fMRI data found that HCs showed widespread bilateral FC patterns associated with the dominant hemispheric primary motor cortex (M1). However, the FC patterns in patients revealed intra-hemispheric association with the ipsilesional M1 seed and this association became visible in the contra-hemisphere after the intervention. Moreover, the change of FC values between the bilateral M1 was significantly correlated with the changes in FM-UE scores (p values < 0.037). We conclude that unilateral and bilateral limb mirroring exercise in an immersive virtual environment may enhance cortical reorganization and lead to improved motor function.

Background: Stroke is a major cause of life-long disability in adults, associated with poor quality of life. Virtual reality (VR)-based therapy systems are known to be helpful in improving motor functions following stroke, but recent clinical findings have not been included in the previous publications of meta-analysis studies. Aims: This meta-analysis was based on the available literature to evaluate the therapeutic potential of VR as compared to dose-matched conventional therapies (CT) in patients with stroke. Methods: We retrieved relevant articles in EMBASE, MEDLINE, PubMed, and Web of Science published between 2010 and February 2019. Peer-reviewed randomized controlled trials that compared VR with CT were included. Results: A total of 27 studies met the inclusion criteria. The analysis indicated that the VR group showed statistically significant improvement in the recovery of UL function (Fugl-Meyer Upper Extremity [FM-UE]: n = 20 studies, Mean Difference [MD] = 3.84, P = .01), activity (Box and Block Test [BBT]: n = 13, MD = 3.82, P = .04), and participation (Motor Activity Log [MAL]: n = 6, MD = 0.8, P = .0001) versus the control group. Conclusion: VR appears to be a promising therapeutic technology for UL motor rehabilitation in patients with stroke.

The relationship between the cognitive impairment and the structural and functional abnormalities in the brains of patients with schizophrenia (SZ) is not yet clear. This study aims to investigate the relationship, thereby exploring the neuromechanism underlying SZ. We collected multimodal MRI data from 68 first-episode, drug-naïve patients with SZ, and 64 well-matched healthy controls, and used regional homogeneity (ReHo) and gray matter volume (GMV) to assess the functional and structural integrity of the brains, respectively. We then evaluated in the entire brain the correlations between ReHo/GMV and the participants' neuropsychological assessment scores for each group using a partial correlation analysis controlling for age and sex. We found significant uncoupling between attention performance and mean ReHo in the left middle frontal gyrus, right superior/inferior parietal lobe (IPL), right angular gyrus (AG) and right middle/inferior temporal lobe (ITG) in SZ compared with healthy controls. Moreover, we found that the SZ group showed decreased GMV in the right IPL and AG, and a significant coupling between ReHo and GMV in the right ITG. Our findings suggest that the attention dysfunction found in SZ may be associated with the structural and functional abnormalities as well as the structure-function interrelation in several SZ-related brain regions., (Copyright © 2019 Elsevier B.V. All rights reserved.)