Therapeutic Effects of Transcranial Magnetic Stimulation on Visuospatial Neglect Revealed With Event-Related Potentials

Virtual reality rehabilitation for unilateral spatial neglect: A systematic review of immersive, semi-immersive and non-immersive techniques

INTRODUCTION

In recent decades, new virtual reality (VR)-based protocols have been proposed for the rehabilitation of Unilateral Spatial Neglect (USN), a debilitating disorder of spatial awareness. However, it remains unclear which type of VR protocol and level of VR immersion can maximize the clinical benefits. To answer these questions, we conducted a systematic review of the use of VR for the rehabilitation of USN.

METHOD

Studies between 2000 and 2022 that met the inclusion criteria were classified according to their research design and degree of immersion (non-immersive, NIVR; semi-immersive, SIVR; immersive, IVR).

RESULTS

A total of 375 studies were identified, of which 26 met the inclusion criteria. Improvements were found in 84.6% of the reviewed studies: 85.7% used NIVR, 100% used SIVR and 55.6% used IVR. However, only 42.3% of them included a control group and only 19.2% were randomized control trials (RCT).

CONCLUSION

VR protocols may offer new opportunities for USN rehabilitation, although further RCTs are needed to validate their clinical efficacy.

Parameters of Auditory Evoked Related Potentials P300 in Disorders of Different Cognitive Function Domains (Visuospatial/Executive and Memory) in Elderly Hypertensive Persons

The neurophysiological correlates of certain types of cognitive impairment in relation to the spatial pattern of auditory cognitive evoked-related potentials (ERPs) in hypertensive persons remain unclear. The aim of this study was to determine the parameters of ERPs (N200, P300) in impaired different domains (visuospatial/executive and memory) of cognitive function in arterial hypertension, including cardiovascular ischemic events. A total of 46 patients (65-84 years) were observed. The clinical diagnosis of vascular dementia, the Montreal Cognitive Assessment Scale (MoCA test) and the spatial pattern of ERPs (N200, P300) were the parameters used to identify three groups: the Control Group without cognitive impairment (n = 13), the group with a leading memory disturbance (Memory Group, n = 20) and the group with a leading visuospatial/executive disturbance (VS/E Group, n = 13). In persons belonging to the Memory Group, N2 latency was prolonged in the central (C3 C4) and right parietal (P4) brain parts; latency of the motor component (P300) may remain similar to that of the ControlGroup. In persons belonging to theVS/E Group, maximal prolonged recognition time (N2), especially in the left central (C3), frontal-midline (Fz), right parietal (P3) and temporal (P4) brain parts, was observed; P300 latency in the central-midline (Cz) and left anterior-temporal (F7) brain parts among all the groups was revealed.

Resting-state electroencephalography changes in poststroke patients with visuospatial neglect

Background

This study aimed to explore the electrophysiological characteristics of resting-state electroencephalography (rsEEG) in patients with visuospatial neglect (VSN) after stroke.

Methods

A total of 44 first-event sub-acute strokes after right hemisphere damage (26 with VSN and 18 without VSN) were included. Besides, 18 age-matched healthy participants were used as healthy controls. The resting-state electroencephalography (EEG) of 64 electrodes was recorded to obtain the power of the spectral density of different frequency bands. The global delta/alpha ratio (DAR), DAR over the affected hemispheres (DAR_AH), DAR over the unaffected hemispheres (DAR_UH), and the pairwise-derived brain symmetry index (pdBSI; global and four bands) were compared between groups and receiver operating characteristic (ROC) curve analysis was conducted. The Barthel index (BI), Fugl-Meyer motor function assessment (FMA), and Berg balance scale (BBS) were used to assess the functional state of patients. Visuospatial neglect was assessed using a battery of standardized tests.

Results

We found that patients with VSN performed poorly compared with those without VSN. Analysis of rsEEG revealed increased delta and theta power and decreased alpha and beta power in stroke patients with VSN. Compared to healthy controls and poststroke non-VSN patients, patients with VSN showed a higher DAR (P < 0.001), which was significantly positively correlated with the BBS (DAR: r = –0.522, P = 0.006; DAR_AH: r = –0.521, P = 0.006; DAR_UH: r = –0.494, P = 0.01). The line bisection task was positively correlated with DAR (r = 0.458, P = 0.019) and DAR_AH (r = 0.483, P = 0.012), while the star cancellation task was only positively correlated with DAR_AH (r = 0.428, P = 0.029). DAR_AH had the best discriminating value between VSN and non-VSN, with an area under the curve (AUC) of 0.865. Patients with VSN showed decreased alpha power in the parietal and occipital areas of the right hemisphere. A higher parieto-occipital pdBSI_alpha was associated with a worse line bisection task (r = 0.442, P = 0.024).

Conclusion

rsEEG may be a useful tool for screening for stroke patients with visuospatial neglect, and DAR and parieto-occipital pdBSI_alpha may be useful biomarkers for visuospatial neglect after stroke.