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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.

Virtual reality (VR) is considered to be a promising therapeutic technology for the rehabilitation of upper extremities (UEs) poststroke. 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.

The stability and rheology of water-in-oil-in-water (W/O/ W) emulsions stabilized by and fatty alkoxy ethylene ether-AEO9 (oil-in-water) were investigated. The addition of salt (NaCl) at varying concentrations into the internal aqueous phase formed a strong network that changed the stability of multiple emulsions. W/O/W emulsions were further modified by varying the disperse phase ratio, concentration of AEO9, and shear forces. Remarkably, the thickening behavior was induced into W/O/W emulsions when the concentration of NaCl (0−0.2 wt %), dispersed phase (ϕ = 0.20−0.33), and shear forces (3000−5000 rpm) varied in the emulsion formulations. An increase of up to 3 orders of magnitude in the viscoelasticity (storage modulus and yield stress) of multiple emulsions was achieved. Multiple emulsion droplets showed strong resistance to coalescence during longterm shelf storage by the formation of a gel-like barrier at the interface. These emulsions products are, therefore, highly versatile formulation with a high degree of stability.

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BackgroundUncontrollable 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.PurposeTo 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 TypeProspective.SubjectsForty‐one PD patients (68.63 ± 9.17 years, 44% female) and 20 healthy controls (66.83 ± 12.94 years, 55% female).Field Strength/Sequence3‐T, T1‐weighted gradient echo and EPI sequences.AssessmentClusters 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 TestsGroup 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.ResultsWith 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 ConclusionThe CVDC method may provide superior sensitivity and improved reproducibility for detecting rsFC deficits in PD.Level of Evidence1Technical EfficacyStage 2

Resting-state fMRI plays an increasing role in understanding the neural mechanisms of Parkinson's disease (PD). However, neural network alterations, regional and global signal associations are not fully understood in PD patients. Here, we studied the whole-brain neural networks including the inter-network and their correlations with the global fluctuation in 37 PD patients and 20 healthy controls. Our findings revealed that the visual cortex had reduced neural network connectivity in PD patients and altered connections from default mode network to other networks. Weaker correlations were observed between the global signal and regional networks in the PD patients than healthy controls.