Computer-Assisted Rehabilitation Shows Greater Efficacy Than Traditional in Visuospatial Skills and Cognition in Neglect Patients.

This study is crucial for improving unilateral spatial neglect (USN) treatments, focusing on comparing the effectiveness of computer-assisted cognitive rehabilitation (CACR) against conventional rehabilitation (CR) methods. It aimed to address a significant research gap and improve patient outcomes by evaluating the impact of CACR versus CR on visuospatial perception, visual field and attention, and visual memory in patients with USN. This study was a randomized controlled trial. Forty-five consecutive patients with USN from a university rehabilitation center were divided into two groups: 22 patients received CACR with Rehacom software, focusing on saccadic eye movement, visual field, and visual-motor coordination, while 23 underwent CR that combined hemispheric activation approach, mental imagery training, and vibration therapy. Assessments included the Motor-Free Visual Perception Test (MVPT), Line Bisection Test (LBT), Visual Span Test (VST), and Visual Recognition Test (VRT). The study employed ANCOVA and effect size calculations to evaluate the effectiveness of CACR compared to CR in treating patients with USN. Results indicated that CACR significantly outperformed CR in improving visuospatial perception, visual field, attention, and memory, showcasing its effectiveness in treating USN. These findings demonstrate the superiority of CACR over CR, particularly in enhancing visual memory and attention, as evidenced by the large effect size in VRT and moderate effects in LBT and VST. This suggests CACR's potential as a more effective approach for rehabilitation in patients with USN due to brain injuries.

Comparison of uni- and multimodal motion stimulation on visual neglect: A proof-of-concept study.

Spatial neglect is characterized by the failure to attend stimuli presented in the contralesional space. Typically, the visual modality is more severely impaired than the auditory one. This dissociation offers the possibility of cross-modal interactions, whereby auditory stimuli may have beneficial effects on the visual modality. A new auditory motion stimulation method with music dynamically moving from the right to the left hemispace has recently been shown to improve visual neglect. The aim of the present study was twofold: a) to compare the effects of unimodal auditory against visual motion stimulation, i.e., smooth pursuit training, which is an established therapeutical approach in neglect therapy and b) to explore whether a combination of auditory + visual motion stimulation, i.e., multimodal motion stimulation, would be more effective than unimodal auditory or visual motion stimulation. 28 patients with left-sided neglect due to a first-ever, right-hemispheric subacute stroke were included. Patients either received auditory, visual, or multimodal motion stimulation. The between-group effect of each motion stimulation condition as well as a control group without motion stimulation was investigated by means of a one-way ANOVA with the patient's visual exploration behaviour as an outcome variable. Our results showed that unimodal auditory motion stimulation is equally effective as unimodal visual motion stimulation: both interventions significantly improved neglect compared to the control group. Multimodal motion stimulation also significantly improved neglect, however, did not show greater improvement than unimodal auditory or visual motion stimulation alone. Besides the established visual motion stimulation, this proof-of-concept study suggests that auditory motion stimulation seems to be an alternative promising therapeutic approach to improve visual attention in neglect patients. Multimodal motion stimulation does not lead to any additional therapeutic gain. In neurorehabilitation, the implementation of either auditory or visual motion stimulation seems therefore reasonable.

Music-based interventions for unilateral spatial neglect: A systematic review.

This study aimed to evaluate the effects of music-based interventions on unilateral spatial neglect. Five databases were retrieved prior to May 5, 2022. A range of study designs were considered, including randomized controlled trials, controlled clinical trials, cohorts, and case series/reports. Types of music-based interventions were not limited. Methodological quality of randomized trials were evaluated using the RoB 2 tool, and the RoBiNT scale was utilized to assess the quality of case studies. Two authors independently summarized main results for assessments. Search strategies identified 186 potentially relevant articles, and 10 articles were collected for in-depth analysis. Preliminary results showed that USN patients performed better in cancellation tests than bisection tests after music-based intervention. In summary, pleasant music listening may have a beneficial effect on the visual attention of USN patients, and it can be hypothesized that this is related to the positive mood and emotions of patients induced by music. Music with a dynamic auditory stimulus as a new music listening programme in USN rehabilitation is worthy of further investigation. Instrument playing intervention can be considered as a multisensory stimulation to ameliorate neglect performance via multiple mechanisms. However, current results only support the short-term positive effects of music-based interventions on USN.

Rehabilitation of hemispatial neglect in stroke.

Hemi-spatial neglect (HSN) is a debilitating post stroke cognitive deficit resulting in reduced attention to stimuli presented in the contra-lateral hemi-visual field. It adversely impacts patient's medical recovery, activities of daily living and quality of life. Early referral to Rehabilitation Medicine specialist for thorough evaluation, prompt recognition of functional impairments and formulation of a comprehensive rehabilitation plan unique to patient is important. It is part of the comprehensive and holistic management of stroke patients with HSN. We summarize the current management strategies used for post-stroke HSN rehabilitation with the options including non-invasive brain stimulation, visuomotor feedback training, robotic rehabilitation and trans-dermal nicotine patch.

Neglect syndrome in post-stroke conditions: assessment and treatment (scoping review).

There is no consensus about the definition or most effective treatment for neglect syndrome. The aim of this review was therefore to evaluate the results of trials that investigated different treatment methods for neglect syndrome. A systematic literature search in PubMed and Web of Science databases was performed to identify studies that investigated the effects of neglect therapies. Authors followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Studies were selected by two assayers, and disagreement was resolved by a third reviewer. The literature search identified 202 articles: 19 met the inclusion criteria and were included for data extraction. Thirty-five different kinds of assessments were used in these studies, and 17 treatment methods were applied. Successful treatments were reported at least in some parts of the assessments in 12 studies: mirror therapy (in two trials), transcranial magnetic stimulation, street crossing test in virtual reality, smooth pursuit eye movement training, saccadic eye movement therapy, direct current stimulation, eye patching therapy, prism adaptation treatment, socially assistive pet-type therapeutic robot (PARO), Kinesiological Instrument for Normal and Altered Reaching Movement robotic device therapy, transcutaneous electrical nerve stimulation, and optokinetic stimulation (the last two methods in the same trial). No success was shown in seven trials, which contained not only single treatments but combined ones also. Authors concluded that there are no convincing results for or against any of the different therapies used for neglect syndrome. The quality of the trials is questionable, and the numbers of included patients are small in the trials.

Modifying the Adult Rat Tonotopic Map with Sound Exposure Produces Frequency Discrimination Deficits That Are Recovered with Training.

Frequency discrimination learning is often accompanied by an expansion of the functional region corresponding to the target frequency within the auditory cortex. Although the perceptual significance of this plastic functional reorganization remains debated, greater cortical representation is generally thought to improve perception for a stimulus. Recently, the ability to expand functional representations through passive sound experience has been demonstrated in adult rats, suggesting that it may be possible to design passive sound exposures to enhance specific perceptual abilities in adulthood. To test this hypothesis, we exposed adult female Long-Evans rats to 2 weeks of moderate-intensity broadband white noise followed by 1 week of 7 kHz tone pips, a paradigm that results in the functional over-representation of 7 kHz within the adult tonotopic map. We then tested the ability of exposed rats to identify 7 kHz among distractor tones on an adaptive tone discrimination task. Contrary to our expectations, we found that map expansion impaired frequency discrimination and delayed perceptual learning. Rats exposed to noise followed by 15 kHz tone pips were not impaired at the same task. Exposed rats also exhibited changes in auditory cortical responses consistent with reduced discriminability of the exposure tone. Encouragingly, these deficits were completely recovered with training. Our results provide strong evidence that map expansion alone does not imply improved perception. Rather, plastic changes in frequency representation induced by bottom-up processes can worsen perceptual faculties, but because of the very nature of plasticity these changes are inherently reversible.SIGNIFICANCE STATEMENT The potent ability of our acoustic environment to shape cortical sensory representations throughout life has led to a growing interest in harnessing both passive sound experience and operant perceptual learning to enhance mature cortical function. We use sound exposure to induce targeted expansions in the adult rat tonotopic map and find that these bottom-up changes unexpectedly impair performance on an adaptive tone discrimination task. Encouragingly, however, we also show that training promotes the recovery of electrophysiological measures of reduced neural discriminability following sound exposure. These results provide support for future neuroplasticity-based treatments that take into account both the sensory statistics of our external environment and perceptual training strategies to improve learning and memory in the adult auditory system.

Association between prism adaptation and auditory cues on spatial navigation in individuals with unilateral neglect.

BACKGROUND: Unilateral neglect is common among right-hemispheric stroke individuals and also concerns the auditory modality. Prism adaptation can improve auditory extinction during a dichotic listening task, but its effect during an ecological task has not been studied. OBJECTIVE: The main objective was to evaluate whether lateralized cueing before and after prism adaptation improved virtual spatial navigation of stroke individuals with visual and auditory unilateral neglect. Secondary objectives were to assess spatial memory and obtain a better understanding of the mechanism of the cueing treatment by using an eye-tracker. METHODS: We included 22 stroke individuals with left visual and auditory neglect, 14 individuals without neglect, and 12 healthy controls. After a familiarization task, participants underwent 3 evaluation sessions. Participants were first passively shown a path that they had then to actively reproduce by using a joystick. A path with lateralized beeping sounds indicating direction and a path without any sounds were followed in a randomized order. After prism adaptation, the participants followed a third path with lateralized beeping sounds. The time of navigation and number of trajectory mistakes were recorded. After navigation, spatial memory was assessed. Additionally, an eye-tracker was used during the navigation period. RESULTS: The navigational performance of participants with neglect was significantly better with than without auditory cues, especially after prism adaptation. With auditory cues, participants without neglect reached the navigational performance of healthy controls. The spatial memory of individuals with neglect was significantly lower with auditory cues. Eye-tracking analyses showed that participants with neglect made more saccades and looked longer at the right-square angles in the absence of auditory cues. CONCLUSIONS: This study demonstrates the positive effect of auditory cues in virtual spatial navigation of individuals with visual and auditory neglect and the potentiation of the help of cues after prism adaptation.

Using real-time fMRI neurofeedback to restore right occipital cortex activity in patients with left visuo-spatial neglect: proof-of-principle and preliminary results.

Hemineglect is common after right parietal stroke, characterised by impaired awareness for stimuli in left visual space, with suppressed neural activity in the right visual cortex due to losses in top-down attention signals. Here we sought to assess whether hemineglect patients are able to up-regulate their right visual cortex activity using auditory real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback. We also examined any effect of this training procedure on neglect severity. Two different neurofeedback methods were used. A first group of six patients was trained to up-regulate their right visual cortex activity and a second group of three patients was trained to control interhemispheric balance between their right and left visual cortices. Over three sessions, we found that the first group successfully learned to control visual cortex activity and showed mild reduction in neglect severity, whereas the second group failed to control the feedback and showed no benefit. Whole brain analysis further indicated that successful up-regulation was associated with a recruitment of bilateral fronto-parietal areas. These findings provide a proof of concept that rt-fMRI neurofeedback may offer a new approach to the rehabilitation of hemineglect symptoms, but further studies are needed to identify effective regulation protocols and determine any reliable impact on clinical symptoms.

Improving left spatial neglect through music scale playing.

The study assessed whether the auditory reference provided by a music scale could improve spatial exploration of a standard musical instrument keyboard in right-brain-damaged patients with left spatial neglect. As performing music scales involves the production of predictable successive pitches, the expectation of the subsequent note may facilitate patients to explore a larger extension of space in the left affected side, during the production of music scales from right to left. Eleven right-brain-damaged stroke patients with left spatial neglect, 12 patients without neglect, and 12 age-matched healthy participants played descending scales on a music keyboard. In a counterbalanced design, the participants' exploratory performance was assessed while producing scales in three feedback conditions: With congruent sound, no-sound, or random sound feedback provided by the keyboard. The number of keys played and the timing of key press were recorded. Spatial exploration by patients with left neglect was superior with congruent sound feedback, compared to both Silence and Random sound conditions. Both the congruent and incongruent sound conditions were associated with a greater deceleration in all groups. The frame provided by the music scale improves exploration of the left side of space, contralateral to the right hemisphere, damaged in patients with left neglect. Performing a scale with congruent sounds may trigger at some extent preserved auditory and spatial multisensory representations of successive sounds, thus influencing the time course of space scanning, and ultimately resulting in a more extensive spatial exploration. These findings offer new perspectives also for the rehabilitation of the disorder.

[Treatment of neglect: new therapy approaches]. / Neglektbehandlung: neue Therapieansätze.

Neglect is a supramodal, clinically relevant disorder, which occurs in the different sensory modalities as well as in the mental representation. The different manifestations of neglect show interindividual and intraindividual variation. Different spatial and attention-related interventions lead to varying degrees of improvement in neglect symptoms but are often not stable in time or transferable to activities of daily living. Representational deficits or body-related aspects to modify personal neglect are rarely a priority in current therapies. Because of the multisensory and motor deficits from our point of view the future of neglect rehabilitation lies in a combined therapy of visual exploration, motor imagery with intensive motor therapy of motor sensory deficits and probably best reinforced by continued neck muscle vibration or allocation of attention to the neglected side.

Aphasia and unilateral spatial neglect due to acute thalamic hemorrhage: clinical correlations and outcomes.

Thalamic hemorrhages are associated with a variety of cognitive dysfunctions, and it is well known that such cognitive changes constitute a limiting factor of recovery of the activities of daily living (ADL). The relationship between cognitive dysfunction and hematomas is unclear. In this study, we investigated the relationship between aphasia/neglect and hematoma volume, hematoma type, and the ADL. One hundred fifteen patients with thalamic hemorrhage (70 men and 45 women) were studied. Their mean age was 68.9 ± 10.3 years, and patients with both left and right lesions were included. We calculated hematoma volume and examined the presence or absence of aphasia/neglect and the relationships between these dysfunctions and hematoma volume, hematoma type, and the ADL. Fifty-nine patients were found to have aphasia and 35 were found to have neglect. Although there was no relationship between hematoma type and cognitive dysfunction, hematoma volume showed a correlation with the severity of cognitive dysfunction. The ADL score and ratio of patient discharge for patients with aphasia/neglect were lower than those for patients without aphasia/neglect. We observed a correlation between the hematoma volume in thalamic hemorrhage and cognitive dysfunction. Aphasia/neglect is found frequently in patients with acute thalamic hemorrhage and may influence the ADL.

Multisensory Stimulation to Improve Low- and Higher-Level Sensory Deficits after Stroke: A Systematic Review.

The aim of this systematic review was to integrate and assess evidence for the effectiveness of multisensory stimulation (i.e., stimulating at least two of the following sensory systems: visual, auditory, and somatosensory) as a possible rehabilitation method after stroke. Evidence was considered with a focus on low-level, perceptual (visual, auditory and somatosensory deficits), as well as higher-level, cognitive, sensory deficits. We referred to the electronic databases Scopus and PubMed to search for articles that were published before May 2015. Studies were included which evaluated the effects of multisensory stimulation on patients with low- or higher-level sensory deficits caused by stroke. Twenty-one studies were included in this review and the quality of these studies was assessed (based on eight elements: randomization, inclusion of control patient group, blinding of participants, blinding of researchers, follow-up, group size, reporting effect sizes, and reporting time post-stroke). Twenty of the twenty-one included studies demonstrate beneficial effects on low- and/or higher-level sensory deficits after stroke. Notwithstanding these beneficial effects, the quality of the studies is insufficient for valid conclusion that multisensory stimulation can be successfully applied as an effective intervention. A valuable and necessary next step would be to set up well-designed randomized controlled trials to examine the effectiveness of multisensory stimulation as an intervention for low- and/or higher-level sensory deficits after stroke. Finally, we consider the potential mechanisms of multisensory stimulation for rehabilitation to guide this future research.

Influence of the stimulus parameters of galvanic vestibular stimulation on unilateral spatial neglect.

Galvanic vestibular stimulation (GVS) stimulates the vestibular system electrically with low-amplitude direct current through surface electrodes applied to the left and right mastoids. The effects of GVS on unilateral spatial neglect (USN) in poststroke patients were recently reported, but the influence of the current intensity and application duration of GVS on USN has not been sufficiently investigated. Here we explored the influence of these stimulus parameters on USN. We recruited seven patients with right-hemisphere stroke and left-sided USN (four female) for this single-blind, sham-controlled cross-over trial. Their scores on the line cancellation test were measured under three stimulation conditions [left-cathodal/right-anodal GVS (L-GVS), right-cathodal/left-anodal GVS, and sham] at three time points (before the start of GVS, 10 min after the start of GVS, and 20 min after the start of GVS). The GVS intensity was set below the sensory threshold and differed among the patients (0.4-2.0 mA). The cancellation scores were significantly increased after 10 and 20 min L-GVS, with a greater increase observed after the latter (P<0.0001). The other stimulus conditions had no significant effect. There was a significant positive correlation between the change in the increase in the cancellation score with L-GVS and the total charge (r=0.81, P=0.0004). The effect of GVS on USN may depend on its application duration, current intensity, and polarity.

Does galvanic vestibular stimulation reduce spatial neglect? A negative study.

INTRODUCTION: In spatial neglect, the functional benefit of rehabilitation methods is subject to debate. A few studies have reported that galvanic vestibular stimulation (GVS) is efficacious in spatial neglect. The objective of the present study was to establish whether the effects of GVS persist after the end of stimulation. MATERIALS: Four patients with pathological rightward deviation in a bisection task at least three months after right hemisphere stroke. A single-blind, randomized crossover design was used to assess the effects of GVS on performance in line bisection and star cancellation tasks under three different conditions (cathode-right, cathode-left and sham stimulation). RESULTS: There were no significant differences in the performance of either task following GVS (relative to sham stimulation). CONCLUSION: Galvanic vestibular stimulation did not reduce spatial neglect symptoms in any of the stimulation conditions. Further studies are necessary to understand the disparity between our results and those reported in the literature. Repeated sessions, a higher current intensity and/or alternating-current stimulation may improve this method before it can be used clinically.

The effectiveness of different treatment modalities for the rehabilitation of unilateral neglect in stroke patients: a systematic review.

BACKGROUND: Patients suffering from unilateral neglect syndrome (UNS) are not able to respond to stimuli administered to the side of the body opposite to the lesion. UNS is most commonly seen after right-hemisphere lesions. Patients with UNS experience more problems with activities of daily living and recovery after stroke is delayed. OBJECTIVE: To investigate which treatment modalities can alleviate the symptoms of UNS after stroke and to determine their effectiveness. METHODS: Databases PubMed, Web of knowledge and PEDro have been searched. Quality assessment was conducted using the 9-item Delphi list. Data extraction was performed by the first author. Effect sizes have been calculated using Cohen's d. RESULTS: 15 RCT's have been included. Most studies used add-on therapies. Almost all studies found improvements in both groups, but only 7 trials showed statistically significant between group differences in favor of the experimental group. Large effect sizes were found in only four studies. CONCLUSIONS: All the interventions discussed in this review can reduce the symptoms of UNS. However, TENS, optokinetic stimulation, somatosensory electrostimulation, mirror therapy and virtual reality training seem to be the most effective treatment methods (d > 0,80). Future research should focus on producing studies of higher methodological quality with larger sample sizes.

The Detection of Motion by Blind Subjects With the Epiretinal 60-Electrode (Argus II) Retinal Prosthesis.

OBJECTIVE: To investigate the ability of 28 blind subjects implanted with a 60-electrode Argus II (Second Sight Medical Products Inc) retinal prosthesis system to detect the direction of a moving object. METHODS: Blind subjects (bare light perception or worse in both eyes) with retinitis pigmentosa were implanted with the Argus II prosthesis as part of a phase 1/2 feasibility study at multiple clinical sites worldwide. The experiment measured their ability to detect the direction of motion of a high-contrast moving bar on a flatscreen monitor in 3 conditions: with the prosthesis system on and a 1-to-1 mapping of spatial information, with the system off, and with the system on but with randomly scrambled spatial information. RESULTS: Fifteen subjects (54%) were able to perform the task significantly better with their prosthesis system than they were with their residual vision, 2 subjects had significantly better performance with their residual vision, and no difference was found for 11 subjects. Of the 15 better-performing subjects, 11 were available for follow-up testing, and 10 of them had significantly better performance with normal rather than with scrambled spatial information. CONCLUSIONS: This work demonstrates that blind subjects implanted with the Argus II retinal prosthesis were able to perform a motion detection task they could not do with their native vision, confirming that electrical stimulation of the retina provides spatial information from synchronized activation of multiple electrodes. TRIAL REGISTRATION: clinicaltrials.gov Identifier:NCT00407602

Galvanic vestibular stimulation improves arm position sense in spatial neglect: a sham-stimulation-controlled study.

BACKGROUND: Disturbed arm position sense (APS) is a frequent and debilitating condition in patients with hemiparesis after stroke. Patients with neglect, in particular, show a significantly impaired contralesional APS. Currently, there is no treatment available for this disorder. Galvanic vestibular stimulation (GVS) may ameliorate neglect and extinction by activating the thalamocortical network. OBJECTIVE: The present study aimed to investigate the immediate effects and aftereffects (AEs; 20 minutes) of subsensory, bipolar GVS (M = 0.6 mA current intensity) on APS in stroke patients with versus without spatial neglect and matched healthy controls. METHODS: A novel optoelectronic arm position device was developed, enabling the precise measurement of the horizontal APS of both arms. In all, 10 healthy controls, 7 patients with left-sided hemiparesis and left-spatial neglect, and 15 patients with left hemiparesis but without neglect were tested. Horizontal APS was measured separately for both forearms under 4 experimental conditions (baseline without GVS, left-cathodal/right-anodal GVS, right-cathodal/left-anodal GVS, sham GVS). The immediate effects during GVS and the AEs 20 minutes after termination of GVS were examined. RESULTS: Patients with neglect showed an impaired contralateral APS in contrast to patients without neglect and healthy controls. Left-cathodal/right-anodal GVS improved left APS significantly, which further improved into the normal range 20 minutes poststimulation. GVS had no effect in patients without neglect but right-cathodal/left-anodal GVS worsened left APS in healthy participants significantly. CONCLUSIONS: GVS can significantly improve the impaired APS in neglect. Multisession GVS can be tested to induce enduring therapeutic effects.