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Background/Objective. This study aims to investigate how complex visuospatial neglect behavioural phenotypes predict long-term outcomes, both in terms of neglect recovery and broader functional outcomes after 6 months post-stroke. Methods. This study presents a secondary cohort study of acute and 6-month follow-up data from 400 stroke survivors who completed the Oxford Cognitive Screen's Cancellation Task. At follow-up, patients also completed the Stroke Impact Scale questionnaire. These data were analysed to identify whether any specific combination of neglect symptoms is more likely to result in long-lasting neglect or higher levels of functional impairment, therefore warranting more targeted rehabilitation. Results. Overall, 98/142 (69%) neglect cases recovered by follow-up, and there was no significant difference in the persistence of egocentric/allocentric (X2 [1] = .66 and P = .418) or left/right neglect (X2 [2] = .781 and P = .677). Egocentric neglect was found to follow a proportional recovery pattern with all patients demonstrating a similar level of improvement over time. Conversely, allocentric neglect followed a non-proportional recovery pattern with chronic neglect patients exhibiting a slower rate of improvement than those who recovered. A multiple regression analysis revealed that the initial severity of acute allocentric, but not egocentric, neglect impairment acted as a significant predictor of poor long-term functional outcomes (F [9,300] = 4.742, P < .001 and adjusted R2 = .098). Conclusions. Our findings call for systematic neuropsychological assessment of both egocentric and allocentric neglect following stroke, as the occurrence and severity of these conditions may help predict recovery outcomes over and above stroke severity alone. ispartof: NEUROREHABILITATION AND NEURAL REPAIR vol:35 issue:9 pages:823-835 ispartof: location:United States status: published

The objective of this scoping review is to clarify how post-stroke perceptual and premotor neglect have been defined across the literature. We will achieve this aim by providing a systematic and comprehensive summary of the measurement approaches and neural underpinnings of these neglect subtypes.

Objectives Visuospatial neglect (VSN) is a common cognitive disorder after stroke. The primary aim of this systematic review was to provide an overview of the impact of VSN in 3 aspects: (1) activities of daily living (ADL), (2) participation, and (3) caregiver burden. The second aim was to investigate the differences in studies focusing on populations with mean age Methods PubMed, EMBASE, Web of Science, Cochrane Library, Emcare, PsychINFO, Academic Search Premier and CENTRAL were searched systematically. Quality was assessed with the Mixed Methods Appraisal Tool. Results Of the 115 included studies, 104 provided outcomes on ADL, 15 on participation (4 studies with mean age ≥ 65), and 2 on caregiver burden (1 study with mean age ≥ 65). Quality assessment yielded scores ranging from 0 to 100%. VSN had a negative impact on ADL (i.e., independence during ADL and performance in self-care, household tasks, reading, writing, walking, wheelchair navigation) and participation (i.e., driving, community mobility, orientation, work). The impact of VSN on fulfilling social roles was unclear. VSN had a negative effect on caregiver burden. We found no clear age-related differences. Conclusions and implications VSN has a negative impact not only on patients’ independence but particularly on the performance of ADL. Despite the far fewer studies of VSN as compared with ADL, VSN also seems to hamper participation and increase caregiver burden, but further research is needed. Because of the large impact, VSN should be systematically and carefully assessed during rehabilitation. A considerable number of different instruments were used to diagnose VSN. Diagnosing VSN at more than one level [function (i.e., pen-and-paper test), activities, and participation] is strongly recommended. Consensus is needed on how to assess VSN and its negative impact for research and rehabilitation practice. Systematic review Registration No. PROSPERPO Registration No. CRD42018087483.

This study aimed to investigate changes in attention processing after low-frequency repetitive transcranial magnetic stimulation (rTMS) over the left posterior parietal cortex to better understand its role in visuospatial neglect (VSN) rehabilitation. The current study included 10 subacute stroke patients with VSN consecutively recruited from the inpatient stroke rehabilitation center at Xuanwu Hospital (the teaching hospital affiliated with Capital Medical University) between March and November 2019. All patients performed a battery of tasks (including line bisection, line cancellation, and star cancellation tests) two weeks before treatment and at the beginning and end of treatment; the attentive components of the test results were analyzed. In addition, low-frequency rTMS was used to stimulate the left posterior parietal cortex for 14 days and event-related potential data were collected before and after the stimulation. Participants were evaluated using a target-cue paradigm and pencil-paper tests. No significant differences were detected on the battery of tasks before rTMS. However, we found that rTMS treatment significantly improved the response times and accuracy rates of patients with VSN. After rTMS, the treatment side (left) amplitude of P300 following an event-related potential was higher than that before treatment (left target, p = 0.002; right target, p = 0.047). Thus, our findings suggest that rTMS may be an effective treatment for VSN. The observed increase in event-related potential amplitude supports the hypothesized compensational role of the contralesional hemisphere in terms of residual performance. Our results provide electrophysiological evidence that may help determine the mechanisms mediating the therapeutic effects of rTMS.

The occurrence of visuospatial neglect acts as a key predictor of recovery outcome following stroke. However, the specific behavioural profiles associated with various neglect subtypes are not well understood. This study aims to identify real-world functional impairments associated with neglect, to determine whether functional impairment profiles differ across patients with egocentric and allocentric neglect, and to investigate how neglect severity predicts functional impairments.Notes from 290 stroke patients' occupational therapy functional assessments were qualitatively and quantitatively analysed in the context of neglect type and severity as reported by the OCS Cancellation Task. Overall, neglect patients had more references to having difficulty initiating tasks, finding items, exhibiting spatial inattention, and having difficulty using both arms than patients without neglect. The proportion of theme references did not differ significantly across patients with egocentric and allocentric neglect. The quantitative severity of egocentric neglect was acted as a significant predictor of reference occurrence over and above stroke severity within difficulty finding items, spatial inattention, body inattention, and upper limb use.This study expands on previous findings by identifying real-world functional impairments differentiating patients with and without neglect. This data provides novel insight into the impact of neglect on functional abilities.

Visuospatial neglect constitutes a supramodal cognitive deficit characterized by reduction or loss of spatial awareness for the contralesional space. It occurs in over 40% of right- and 20% of left-brain-lesioned stroke patients with lesions located mostly in parietal, frontal and subcortical brain areas. Visuospatial neglect is a multifaceted syndrome - symptoms can be divided into sensory, motor and representational neglect - and therefore requires an individually adapted diagnostic and therapeutic approach. Several models try to explain the origins of visuospatial neglect, of which the “interhemispheric rivalry model” is strongly supported by animal and human research. This model proposes that allocation of spatial attention is balanced by transcallosal inhibition and both hemispheres compete to direct attention to the contralateral hemi-space. Accordingly, a brain lesion causes an interhemispheric imbalance, which may be re-installed by activation of lesioned, or deactivation of unlesioned (over-activated) brain areas through noninvasive brain stimulation. Research in larger patient samples is needed to confirm whether noninvasive brain stimulation can improve long-term outcomes and whether these also affect activities of daily living and discharge destination.

Visuospatial neglect (VN) frequently occurs in Posterior Cortical Atrophy (PCA) and requires specific rehabilitation. In this single-case study, we investigated the efficacy of a computer-assisted cognitive training (CCT) alone or coupled with multiple sessions of anodal transcranial direct-current stimulation (A-tDCS) over the right posterior parietal cortex in improving left VN symptoms in a patient with PCA. The digital ReMoVES platform was used for both VN assessment and training. We found a significant improvement after CCT combined with A-tDCS within the limits of a single-case, our results suggest, for the first time, the usefulness of this combined approach in a neurodegenerative disorder.

Introduction: Visuospatial neglect (VSN) is common after stroke and can seriously hamper everyday life. One of the most commonly used and highly recommended rehabilitation methods is Visual Scanning Training (VST) which requires a lot of repetition which makes the treatment intensive and less appealing for the patient. The use of eHealth in healthcare can increase options regarding improved treatment in the areas of patient satisfaction, treatment efficacy and effectiveness. One solution to motivational issues might be Augmented Reality (AR), which offers new opportunities for increasing natural interactions with the environment during treatment of VSN. Aim: The development of an AR-based scanning training program that will improve visuospatial search strategies in individuals affected by VSN. Method: We used a Design Research approach, which is characterized by the iterative and incremental use of prototypes as research instruments together with a strong human-centered focus. Several design thinking methods were used to explore which design elements the AR game should comply with. Seven patients with visuospatial neglect, eight occupational therapists, a game design professional and seven other healthcare professionals participated in this research by means of co-creation based on their own perspectives. Results: Fundamental design choices for an AR game for VSN patients included the factors extrinsic motivation, nostalgia, metaphors, direct feedback, independent movement, object contrast, search elements and competition. Designing for extrinsic motivation was considered the most important design choice, because due to less self-awareness the target group often does not fully understand and accept the consequences of VSN. Conclusion: This study produced a prototype AR game for people with VSN after stroke. The AR game and method used illustrate the promising role of AR tools in geriatric rehabilitation, specifically those aimed at increasing the independence of patients with VSN after stroke. 2020 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Introduction: Visuospatial neglect (VSN) is common after stroke and can seriously hamper everyday life. One of the most commonly used and highly recommended rehabilitation methods is Visual Scanning Training (VST) which requires a lot of repetition which makes the treatment intensive and less appealing for the patient. The use of eHealth in healthcare can increase options regarding improved treatment in the areas of patient satisfaction, treatment efficacy and effectiveness. One solution to motivational issues might be Augmented Reality (AR), which offers new opportunities for increasing natural interactions with the environment during treatment of VSN. Aim: The development of an AR-based scanning training program that will improve visuospatial search strategies in individuals affected by VSN. Method: We used a Design Research approach, which is characterized by the iterative and incremental use of prototypes as research instruments together with a strong human-centered focus. Several design thinking methods were used to explore which design elements the AR game should comply with. Seven patients with visuospatial neglect, eight occupational therapists, a game design professional and seven other healthcare professionals participated in this research by means of co-creation based on their own perspectives. Results: Fundamental design choices for an AR game for VSN patients included the factors extrinsic motivation, nostalgia, metaphors, direct feedback, independent movement, object contrast, search elements and competition. Designing for extrinsic motivation was considered the most important design choice, because due to less self-awareness the target group often does not fully understand and accept the consequences of VSN. Conclusion: This study produced a prototype AR game for people with VSN after stroke. The AR game and method used illustrate the promising role of AR tools in geriatric rehabilitation, specifically those aimed at increasing the independence of patients with VSN after stroke. 2020 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Neglect is a disabling neuropsychological syndrome that is frequently observed following right-hemispheric stroke. Affected individuals often present with multiple attentional deficits, ranging from reduced orienting towards contralesional space to a generalized impairment in maintaining attention over time. Although a degree of spontaneous recovery occurs in most patients, in some individuals this condition can be treatment-resistant with prominent ongoing non-spatial deficits. Further, there is a large inter-individual variability in response to different therapeutic approaches. Given its potential to alter neuronal excitability and affect neuroplasticity, non-invasive brain stimulation is a promising tool that could potentially be utilized to facilitate recovery. However, there are many outstanding questions regarding its implementation in this heterogeneous patient group. Here we provide a critical overview of the available evidence on the use of non-invasive electrical brain stimulation, focussing on transcranial direct current stimulation (tDCS), to improve neglect and associated attentional deficits after right-hemispheric stroke. At present, there is insufficient robust evidence supporting the clinical use of tDCS to alleviate symptoms of neglect. Future research would benefit from careful study design, enhanced precision of electrical montages, multi-modal approaches exploring predictors of response, tailored dose-control applications and increased efforts to evaluate standalone tDCS versus its incorporation into combination therapy.

Consistently lateralized reading errors are commonly understood as side-effects of visuospatial neglect impairment. There is however a qualitative difference between systematically omitting full words presented on one side of passages (egocentric neglect dyslexia) and lateralized errors when reading single words (allocentric neglect dyslexia). This study aims to investigate the relationship between egocentric and allocentric neglect dyslexia and visuospatial neglect. 1209 stroke survivors completed standardized reading and cancellation tests. Stringent criteria identified unambiguous cases of allocentric neglect dyslexia (N = 17) and egocentric neglect dyslexia (N = 35). These conditions were found to be doubly dissociated with all cases of egocentric and allocentric neglect dyslexia occurring independently. Allocentric neglect dyslexia was dissociated from both egocentric and allocentric visuospatial neglect. Additionally, two cases of allocentric neglect dyslexia which co-occurred with oppositely lateralized domain-general visuospatial neglect were identified. Conversely, all cases of egocentric neglect dyslexia were found in the presence of domain-general visuospatial neglect. These findings suggest that allocentric neglect dyslexia cannot be fully understood as a consequence of visuospatial neglect. In contrast, we found no evidence for a dissociation between egocentric neglect dyslexia and visuospatial neglect. These findings highlight the need for new, neglect dyslexia specific rehabilitation strategies to be designed and tested. ispartof: Journal Of Clinical And Experimental Neuropsychology vol:42 issue:4 pages:1-11 ispartof: location:England status: Published online

To identify studies concerning the effects of computer based cognitive rehabilitation (CBCR) on visuospatial neglect (VN) after stroke to summarize the current state of knowledge in this research field and make recommendations for future research.Four electronic databases were systematically searched. Authors of relevant studies were contacted to detect unpublished data or articles not found by searching databases. Data was extracted from included studies using predefined coding schemes and characteristics and results of individual studies were summarized qualitatively.Studies were included if at least 50% of the included patients had a stroke, if the studies explored the effects of CBCR as a primary intervention for rehabilitation of VN and if they included neuropsychological outcome measures for the presence of VN.Seven studies were included. Six of the seven studies suggested positive effects of CBCR on VN after stroke. However, the study that did not find these effects was also the study with the strongest methodological quality. All included studies consisted of small samples, varied greatly in design and had various methodological limitations.Because the existing literature is very sparse and studies have various methodological limitations, it is currently not possible to either support or reject the effects of CBCR on VN after stroke. Future studies should aim to compare CBCR with active and passive control conditions and include larger samples in randomized and blinded designs.

Rehabilitation of patients with chronic visuospatial neglect is underexplored, and little is known about neural mechanisms that can be exploited to promote recovery. In this study, we present data on resting-state functional connectivity within the dorsal attention network (DAN) in chronic neglect patients as they underwent training in a virtual reality (VR) environment that improved left-side awareness.The study included 13 patients with visuospatial neglect persisting more than six months after a right-sided stroke. The patients underwent resting-state functional magnetic resonance imaging (fMRI). Scans were collected at baseline and after five weeks of intense training. We specifically examined resting-state functional connectivity within the DAN. In addition, using spatial concordance correlation, we compared changes in the spatial topology of the DAN with that of other networks.We found a longitudinal increase in interhemispheric functional connectivity between the right frontal eye field and the left intraparietal sulcus following training (before: 0.33 ± 0.17 [mean ± SD]; after: 0.45 ± 0.13; P = 0.004). The spatial concordance analyses indicated that training influenced the DAN connectivity more than any of the other networks.Intense VR training that improved left-sided awareness in chronic stroke patients also increased sporadic interhemispheric functional connectivity within the DAN. Specifically, a region responsible for saccadic eye movement to the left became more integrated with the left posterior parietal cortex. These results highlight a mechanism that should be exploited in the training of patients with chronic visuospatial neglect.

Background Visuospatial neglect (VSN) impairs the control of locomotor heading in post-stroke individuals, which may affect their ability to safely avoid moving objects while walking. Objective We aimed to compare VSN+ and VSN− stroke individuals in terms of changes in heading and head orientation in space while avoiding obstacles approaching from different directions and reorienting toward the final target. Methods Stroke participants with VSN (VSN + ) and without VSN (VSN−) walked in a virtual environment avoiding obstacles that approached contralesionally, head-on or ipsilesionally. Measures of obstacle avoidance (onset-of-heading change, maximum mediolateral deviation) and target alignment (heading and head-rotation errors with respect to target) were compared across groups and obstacle directions. Results In total, 26 participants with right-hemisphere stroke participated (13 VSN+ and 13 VSN−; 24 males; mean age 60.3 years, range 48 to 72 years). A larger proportion of VSN+ (75%) than VSN− (38%) participants collided with contralesional and head-on obstacles. For VSN− participants, deviating to the same side as the obstacle was a safe strategy to avoid diagonal obstacles and deviating to the opposite-side led to occasional collisions. VSN+ participants deviated ipsilesionally, displaying same-side and opposite-side strategies for ipsilesional and contralesional obstacles, respectively. Overall, VSN+ participants showed greater distances at onset-of-heading change, smaller maximum mediolateral deviation and larger errors in target alignment as compared with VSN− participants. Conclusion The ipsilesional bias arising from VSN influences the modulation of heading in response to obstacles and, along with the adoption of the “riskier” strategies, contribute to the higher number colliders and poor goal-directed walking abilities in stroke survivors with VSN. Future research should focus on developing assessment and training tools for complex locomotor tasks such as obstacle avoidance in this population.

Background Position sense is commonly impaired after stroke. Traditional rehabilitation methods instruct patients to visualize their limbs to compensate for impaired position sense. Objective Our goal was to evaluate how the use of vision influences impaired position sense. Methods We examined 177 stroke survivors, an average of 12.7 days (+/− 10 days (SD)) post-stroke, and 133 neurologically-intact controls with a robotic assessment of position sense. The robot positioned one limb (affected) and subjects attempted to mirror-match the position using the opposite limb (unaffected). Subjects completed the test without, then with vision of their limbs. We examined three measures of position sense: variability (Var), contraction/expansion (C/E) and systematic shift (Shift). We classified stroke survivors as having full compensation if they performed the robotic task abnormally without vision but corrected performance within the range of normal with vision. Stroke survivors were deemed to have partial compensation if they performed the task outside the range of normal without and with vision, but improved significantly with vision. Those with absent compensation performed the task abnormally in both conditions and did not improve with vision. Results Many stroke survivors demonstrated impaired position sense with vision occluded [Var: 116 (66%), C/E: 91 (51%), Shift: 52 (29%)]. Of those stroke survivors with impaired position sense, some exhibited full compensation with vision [Var: 23 (20%), C/E: 42 (46%), Shift: 32 (62%)], others showed partial compensation [Var: 37 (32%), C/E: 8 (9%), Shift: 3 (6%)] and many displayed absent compensation (Var: 56 (48%), C/E: 41 (45%), Shift: 17 (33%)]. Stroke survivors with an affected left arm, visuospatial neglect and/or visual field defects were less likely to compensate for impaired position sense using vision. Conclusions Our results indicate that vision does not help many stroke survivors compensate for impaired position sense, at least within the current paradigm. This contrasts with historical reports that vision helps compensate for proprioceptive loss following neurologic injuries.

This paper presents the immersive virtual reality (VR) application iVRoad for the detection of unilateral visuospatial neglect in right hemisphere poststroke patients. With our immersive VR tool, it is possible to perform realistic road crossing in a safe environment using a head-mounted display (HMD). We present and discuss the virtual environment (VE) for an upcoming study with neglect patients, a broad range of neurological patients and a healthy control group. Our aim is to determine whether extrapersonal neglect can be reliably diagnosed in the chronic phase using VR with the help of various measured values (task completion time, errors, head rotations, eye tracking).

Objectives: The purpose of this pilot study was to investigate the feasibility and effects of computer-based cognitive rehabilitation (CBCR) in patients with symptoms of visuospatial neglect or homonymous hemianopia in the subacute phase following stroke. Method: A randomized, controlled, unblinded cross-over design was completed with early versus late CBCR including 7 patients in the early intervention group (EI) and 7 patients in the late intervention group (LI). EI received CBCR training immediately after inclusion (m = 19 days after stroke onset) for 3 weeks and LI waited for 3 weeks after inclusion before receiving CBCR training for 3 weeks (m = 44 days after stroke onset). Results: CBCR improved visuospatial symptoms after stroke significantly when administered early in the subacute phase after stroke. The same significant effect was not found when CBCR was administered later in the rehabilitation. The difference in the development of the EI and LI groups during the first 3 weeks was not significant, which could be due to a lack of statistical power. CBCR did not impact mental well-being negatively in any of the groups. In the LI group, the anticipation of CBCR seemed to have a positive impact of mental well-being. Conclusion: CBCR is feasible and has a positive effect on symptoms in patients with visuospatial symptoms in the subacute phase after stroke. The study was small and confirmation in larger samples with blinded outcome assessors is needed.

Patients with visuospatial neglect (VSN) suffer from an imbalance in visual attention between their left and right (egocentric or allocentric) hemispace. The view of VSN as an attentional imbalance between two hemispaces ignores the fact that—in our daily life—we are presented with varying levels of stimulus density, within but also across hemispaces. Therefore, we developed a novel experimental paradigm in which stroke patients (n = 207) were presented with a different number of simple objects in the left and right (egocentric) hemispaces and were asked to indicate whether there were more objects in the left or the right hemispace. We systematically varied the density of visual stimuli to investigate whether a high level of stimulus density impairs task performance of patients with VSN to a larger degree than it does for patients without VSN. Error rate increased when more objects were presented in the display, but this effect was most pronounced in patients with VSN, especially when more objects were presented in their contralesional than in their ipsilesional hemispace. Our findings reveal that deficits in early visual processing in patients with VSN become especially apparent when overall stimulus density is high. The degree of stimulus density should therefore be taken into account when considering the impact of attentional deficits on activities in daily life.

The diagnosis of Visuospatial neglect is generally conducted using paper based manual methods. The obtained results could be confused with sensory inattention pathology. In this paper we are presenting a new Virtual Reality based diagnosis method for patients suffering from Visuospatial neglect. For this purpose a Virtual Reality simulation called Farm Parade has been developed where the patient, after wearing a Virtual Reality headset, will be guided inside a road crossing a farm like environment where animals at both sides of the road will slowly move and generate sounds to encourage patients to look at them. The patient head motion will be then tracked to generate a graph showing his capacity to move his head and judge if he is suffering from Visuospatial neglect. The strength of the proposed system is the generation of numerical values relative to the amount of head’s rotation which could be helpful for measuring precisely the degree of recovery.

Background and objective. Proportional recovery of upper-extremity motor function and aphasia after stroke may suggest common mechanisms for spontaneous neurobiological recovery. This study aimed to investigate if the proportional recovery rule also applies to visuospatial neglect (VSN) in right-hemispheric first-ever ischemic stroke patients and explored the possible common underlying mechanisms. Methods. Patients with upper-limb paresis and VSN were included. Recovery defined as the change in Letter Cancellation Test (LCT) score at ~8 days and 6 months poststroke. Potential recovery defined as LCTmax-LCTinitial = 20 − LCTinitial. Hierarchical clustering separated fitters and nonfitters of the prediction rule. A cutoff value on LCTmax-LCTinitial was determined. The change in LCT and Fugl-Meyer Assessment Upper Extremity was expressed as a percentage of the total possible score to investigate the communality of proportional recovery. Results. Out of 90 patients, 80 displayed proportional recovery of VSN (ie, “fitters,” 0.97; 95% CI = 0.82-1.12). All patients who did not follow the prediction rule for VSN (ie, ”nonfitters”) had ≥15 missing O’s at baseline and failed to show proportional recovery of the upper limb. Conclusions. This study shows that the proportional recovery rule also applies to patients with VSN poststroke. Patients who fail to show proportional recovery of VSN are the same patients who fail to show proportional recovery of the upper limb. These findings support the idea of common intrahemispheric mechanisms underlying spontaneous neurobiological recovery in the first months poststroke. Future studies should investigate the prognostic clinical and neurobiological markers of these subgroups.

Unilateral visuospatial neglect and neglect dyslexia are neuropsychological syndromes in which patients exhibit consistently lateralised perceptual deficits. However, there is little agreement surrounding whether neglect dyslexia is best understood as a consequence of a domain-general visuospatial neglect impairment or as an independent, content-specific cognitive deficit. Previous case studies have revealed that neglect dyslexia is an exceptionally heterogeneous condition and have strongly suggested that not all neglect dyslexia patient error patterns can be fully explained as a consequence of domain-general visuospatial neglect impairment. Additionally, theoretical models which attempt to explain neglect dyslexia as a consequence of domain-general unilateral visuospatial neglect fail to account for neglect dyslexia errors which occur when reading vertically presented words, lack of neglect errors when reading number strings, and neglect dyslexia which co-occurs with oppositely lateralised domain-general visuospatial neglect. Cumulatively, these shortcomings reveal that neglect dyslexia cannot always be accurately characterised as a side-effect of domain-general visuospatial unilateral neglect deficits. These findings strongly imply that neglect dyslexia may be better understood as a content-specific impairment.

Neglect Dyslexia is a neuropsychological syndrome in which patients commit consistently lateralised letter omission, addition, and substitution errors when reading individual words. Although neglect dyslexia frequently co-occurs with domain-general visuospatial neglect, some cases of neglect dyslexia may be best characterised as a dissociable impairment within a word-centred reference frame. This investigation employs data from a single case study of a patient who demonstrated word-centred neglect dyslexia to clarify neglect dyslexia's relationship with visuospatial neglect. AB completed the Oxford Cognitive Screen and an original reading assessment in which she read 302 words, pseudo-words, and numbers presented in normal, vertical, and mirror-reflected orientations. AB was found to commit consistently lateralised right neglect dyslexia errors (e.g., SHOWN misread as "show" or RELATED misread as "relate"). By contrast, AB did not exhibit object-centred or viewer-centred neglect. AB was also found to commit lateralised reading errors affecting the terminal portions of words when lateralised spatial bias was eliminated by presenting words vertically. Additionally, AB consistently misread terminal letters (originally right-lateralised) even when words were mirror-reflected so that these letters were presented in the left side of space. AB committed no neglect dyslexia errors when reading normally, vertically, or mirror-reflected numbers, and demonstrated a qualitatively different error pattern when reading pseudo-words. The results of this case study imply that neglect dyslexia can involve a content-specific, word-centred cognitive deficit and can be dissociated from egocentric and allocentric visuospatial neglect.

Spatial neglect is a debilitating disorder frequently observed after damage to the right cerebral hemisphere. Previous investigations have revealed that prism adaptation (PA) therapy can lead to improvements in neglect-related symptoms. In the typical PA protocol patients repeatedly point toward a visual target while wearing prism goggles. A few years ago, a novel PA procedure, involving a variety of more "ecological" visuo-motor activities during adaptation, less repetitive than a sequence of pointings, was introduced by our research group, and shown to be able to improve neglect-related symptoms to the same extent as the standard pointing task. The ecological procedure was easy to administer and pleasant for the patients. In all previous studies, patients were treated by specialized personnel during hospitalization. In the current study, we investigated the effectiveness of the ecological PA method when performed in a home-based setting, with the help of caregivers and family members. Seven right-brain-damaged patients with chronic left spatial neglect underwent a two-week ecological PA treatment, extended, for two extra weeks, in 6 patients, who were available for this additional rehabilitation session. As a control treatment, patients performed the same activities while wearing neutral goggles, before the PA procedure. Two weeks of ecological PA training proved to be able to significantly improve performance in neuropsychological tests (BIT, Cancellation tasks), a neurological scale (NIH), and functional abilities (CBS), when compared to both the baseline and the neutral control treatment, with improvements being maintained over 6 months. The ecological home-based PA training is effective in alleviating signs of spatial neglect. Importantly, this training is affordable, pleasant, and feasible to be performed in the comfort of the patient's home. Easily extendable to larger patient populations and prolonged periods, this method has a real potential to benefit the quality of life of brain-damaged patients with left spatial neglect.

La negligencia visuoespacial es un síndrome incapacitante, que suele ocurrir tras lesiones hemisféricas derechas y que supone una afectación en la vida diaria de los pacientes. No siendo sólo un déficit en los aspectos atencionales, sino que puede ir acompañado de déficit en otros procesos cognitivos, conductuales y emocionales. Observándose que no es un proceso unitario y que no afecta por igual a todos los pacientes. Se aplicó a una muestra de 38 participantes (media edad: 48,69 De: 8,70) que sufrían de negligencia visuoespacial tras un ictus hemisférico derecho una batería de exploración visuoespacial, dividiéndolos en tres perfiles de afectación (leve, moderado y grave) mediante clustering jerárquico. Aplicándose un paradigma experimental denominado Paradigma de Atenciones Múltiples en conjunción a un eye-tracker tanto a los participantes del grupo experimental, como a un grupo normativo formado por 21 sujetos (media edad: 45,57 De:10,17) sin afectación cognitiva. La aplicación de este set experimental de paradigma y eye-tracker se realizaba antes y después del tratamiento neurorehabilitador realizado en el Institut Guttmann. El paradigma experimental consistía en la respuesta manual ante un estímulo (una X de color negro) de aparición repentina en diferentes posiciones en el espacio (a lo largo de 5 columnas). Con este paradigma experimental y la tecnología de eye-tracking se buscaba estudiar la capacidad de captura atencional, así como la velocidad de captura y respuesta que se muestra afectada tras un ictus hemisférico derecho. En el análisis pre-tratamiento los tres perfiles muestran respuesta diferentes, siendo el perfil grave el que tiene una peor captura atencional y menor velocidad de respuesta ante estímulos en el hemicampo izquierdo. Sin cambios en la velocidad de captura y en la rectitud de búsqueda de un estímulo. Mostrando estos participantes diagnosticados de negligencia espacial una capacidad de captura atencional en el hemicampo izquierdo, pero diferente en función de su grado de afectación atencional. Tras el tratamiento neurorehabilitador intensivo se observa una mejora de la captura atencional en el hemicampo izquierdo de todos los perfiles, con un incremento de la captura y mejora de la velocidad de repuesta del perfil grave en el hemicampo izquierdo. Los resultados de este estudio indican la importancia de la clasificación del grado de afectación de la negligencia espacial, ya que no todos los pacientes diagnosticados de negligencia espacial se comportan de similar manera. Así mismo estos sujetos muestran una diferente capacidad de captura atencional y velocidad de captura y respuesta que no es observada en las pruebas de exploración neuropsicológica. Siendo necesaria una valoración de estos aspectos debido a su influencia en el síndrome de negligencia y en su rehabilitación. Pudiendo aplicarse tareas informatizadas de captura atencional con aparición repentina de los estímulos de cara a mejorar la captura en el hemicampo negligido tras una lesión hemisférica derecha., Visuo-spatial neglect is a disabling syndrome, which usually occurs after right hemispheric injuries and involves an affectation in the daily life of the patients. Not only being a deficit in attentional aspects, it can be accompanied by a deficit in cognitive, behavioral and emotional processes. Observing that it is not a unitary process and it does not affect all patients equally. It was applied to a sample of 38 participants (average age: 48.69 De: 8.70) who suffered visuospatial neglect after a right hemispheric stroke a visuospatial examination battery, dividing them into three profiles of visuospatial neglect (mild, moderate and severe) through hierarchical clustering. An experimental paradigm called the Multiple Attention Paradigm was applied in conjunction with an eye-tracker, both to the participants of the experimental group and to a normative group made up of 21 subjects (average age: 45.57 De: 10.17) without cognitive impairment. The application of this experimental set of paradigm and eye-tracker was performed before and after the neurorehabilitation treatment implemented at the Institut Guttmann. The experimental paradigm consisted of the manual response to a stimulus (a black X) of sudden appearance in different positions in space (along 5 columns). With this experimental paradigm and eye-tracking technology, the aim was to study the ability to capture attention, as well as the speed of capture and response that is affected after a right hemispheric stroke. In the pre-treatment analysis, the three profiles show different responses, with the severe profile having the worst attentional capture and the lowest response speed to stimuli in the left hemifield. No changes in the speed of capture and in the search straightness of a stimulus. These participants, diagnosed with spatial negligence, showed an attentional capture capacity in the left hemifield, but different depending on their degree of attentional involvement. After the intensive neurorehabilitation treatment, an improvement in the attentional capture in the left hemifield of all the profiles was observed, with an increase in the attentional capture and improvement in the speed of response of the severe profile in the left hemifield. The results of this study indicate the importance of classifying the degree of spatial negligence, since not all patients diagnosed behave in a similar way. Likewise, these subjects show a different capacity of attention capture and speed of capture and response that is not observed in the neuropsychological examination tests. An assessment of these aspects is necessary due to its influence on the negligence syndrome and its rehabilitation. Being able, to apply computerized tasks of attention capture with sudden appearance of the stimuli, in order to improve the capture in the neglected hemifield after a right hemispheric lesion.

Visuospatial neglect is a disorder that can often result from stroke and is characterized by an inability to attend to contralesional stimuli. Two common subtypes include allocentric (object-centered) neglect and egocentric (viewer-centered) neglect. In allocentric neglect, spatial inattention is localized to the contralesional side of an object regardless of its relative position to the observer. In egocentric neglect, spatial inattention is localized to the contralesional side of the individual's midline. The neuroanatomical correlates of each subtype are unknown. However, recent work has suggested that damage to temporal, inferior parietal, and occipital areas may result in allocentric neglect and that damage to frontoparietal areas may result in egocentric neglect. We used voxel-based lesion-symptom mapping (VLSM) to compare lesion location to behavioral performance on the conventional six subtests of the Behavioral Inattention Test (BIT) in 62 subjects with acute right hemisphere ischemic stroke. Results identified an anatomical dissociation in lesion location between subjects with neglect based on poor performance on allocentric tests (line bisection, copying, and drawing tasks) and on egocentric tests (star, letter, and line cancellation). VLSM analyses revealed that poor performance on the allocentric tests was associated with lesions to the superior and inferior parietal cortices, and the superior and middle temporal gyri. In contrast, poor performance on the egocentric tests was associated with lesions in the precentral gyrus, middle frontal gyrus, insula, and putamen. Interestingly, the letter cancellation test and average performance on egocentric tests were associated with frontal and parietal lesions. Some of these parietal lesion locations overlapped with lesion locations associated with allocentric neglect. These findings are consistent with suggestions that damage to temporal and parietal areas is more associated with allocentric neglect and damage to frontal lobe areas is more associated with egocentric neglect.

Persons with post-stroke visuospatial neglect (VSN) often collide with moving obstacles while walking. It is not well understood whether the collisions occur as a result of attentional-perceptual deficits caused by VSN or due to post-stroke locomotor deficits. We assessed individuals with VSN on a seated, joystick-driven obstacle avoidance task, thus eliminating the influence of locomotion. Twelve participants with VSN were tested on obstacle detection and obstacle avoidance tasks in a virtual environment that included three obstacles approaching head-on or 30 $^{\circ}$ contralesionally/ipsilesionally. Our results indicate that in the detection task, the contralesional and head-on obstacles were detected at closer proximities compared to the ipsilesional obstacle. For the avoidance task collisions were observed only for the contralesional and head-on obstacle approaches. For the contralesional obstacle approach, participants initiated their avoidance strategies at smaller distances from the obstacle and maintained smaller minimum distances from the obstacles. The distance at detection showed a negative association with the distance at the onset of avoidance strategy for all three obstacle approaches. We conclusion the observation of collisions with contralesional and head-on obstacles, in the absence of locomotor burden, provides evidence that attentional-perceptual deficits due to VSN, independent of post-stroke locomotor deficits, alter obstacle avoidance abilities.

Objective To investigate whether the efficacy of continuous theta-burst stimulation (cTBS) for improving visuospatial neglect can be enhanced by providing more days of stimulation and more stimulation trains per day. Methods In a prospective study, right-handed patients with right hemisphere stroke and visuospatial neglect were randomized to cTBS or sham cTBS treatment for 2 weeks and were followed up for 4 weeks. The cTBS group received active cTBS over the posterior parietal cortex of the unaffected hemisphere, combined with conventional rehabilitation therapy. Changes in scores for two paper–pencil tests for visuospatial neglect (star cancellation and line bisection) were evaluated. Results In each group, 10 patients completed follow up. Compared with the sham group, star cancellation test scores in the cTBS group were improved by 37.03% at the end of treatment and by 47.21% after 4 weeks’ follow up, and the line bisection score improved by 21.37% at the end of treatment and by 35.99% after 4 weeks’ follow up. Conclusions These results suggest that the efficacy of cTBS in visuospatial neglect can be enhanced and prolonged by increasing the days of stimulation and the number of stimulation trains per day over the left posterior parietal cortex.

BACKGROUND Persons with perceptual-attentional deficits due to visuospatial neglect (VSN) after a stroke are at a risk of collisions while walking in the presence of moving obstacles. The attentional burden of performing a dual-task may further compromise their obstacle avoidance performance, putting them at a greater risk of collisions. OBJECTIVE The objective of this study was to compare the ability of persons with (VSN+) and without VSN (VSN-) to dual task while negotiating moving obstacles. METHODS Twenty-six stroke survivors (13 VSN+, 13 VSN-) were assessed on their ability to (a) negotiate moving obstacles while walking (locomotor single task); (b) perform a pitch-discrimination task (cognitive single task) and (c) simultaneously perform the walking and cognitive tasks (dual task). We compared the groups on locomotor (collision rates, minimum distance from obstacle and onset of strategies) and cognitive (error rates) outcomes. RESULTS For both single and dual task walking, VSN+ individuals showed higher collision rates compared to VSN- individuals. Dual tasking caused deterioration of locomotor (more collisions, delayed onset and smaller minimum distances) and cognitive performances (higher error rate) in VSN+ individuals. Contrastingly, VSN- individuals maintained collision rates, increased minimum distance, but showed more cognitive errors, prioritizing their locomotor performance. CONCLUSION Individuals with VSN demonstrate cognitive-locomotor interference under dual task conditions, which could severely compromise safety when ambulating in community environments and may explain the poor recovery of independent community ambulation in these individuals.

Currently there seems to be consensus that visuospatial neglect may involve egocentric and allocentric symptoms. However, the relation between the two is still discussed and models have been proposed based on the high correlation between allocentric and egocentric neglect symptoms. To analyze the relation between these two kinds of symptoms we developed a new paradigm. In contrast to previous paradigms, we varied the extension of the search field and we added centered reference targets to evaluate egocentric effects independent from allocentric effects. Patients with exclusively left-sided neglect (n = 15) and left-sided visual field deficit (VFD) (n = 9) were included. Right brain damaged patients (n = 15) and a healthy control (n = 15) acted as control groups. The results revealed egocentric inattention in VFD patients. Neglect patients suffered from egocentric and allocentric neglect, but we found no interaction between both kinds of impairments in the sense of a monotonous additive or multiplicative increase going from right to left in terms of egocentric and allocentric coordinates. On the contrary, at the outmost left allocentric and egocentric positions, the number of omissions did not increase, unlike in outmost right and centered positions. In conclusion, our experiment shows that egocentric and allocentric neglect can be clearly dissociated in neglect patients and do not interact. Inclusion of neglect patients with a VFD may lead to an artificial interaction between egocentric and allocentric symptoms and this may explain the differences with results of previous studies.

Background. After stroke, visuospatial and kinesthetic (sense of limb motion) deficits are common, occurring in approximately 30% and 60% of individuals, respectively. Although both types of deficits affect aspects of spatial processing necessary for daily function, few studies have investigated the relationship between these 2 deficits after stroke. Objective. We aimed to characterize the relationship between visuospatial and kinesthetic deficits after stroke using the Behavioral Inattention Test (BIT) and a robotic measure of kinesthetic function. Methods. Visuospatial attention (using the BIT) and kinesthesia (using robotics) were measured in 158 individuals an average of 18 days after stroke. In the kinesthetic matching task, the robot moved the participant’s stroke-affected arm at a preset direction, speed, and magnitude. Participants mirror-matched the robotic movement with the less/unaffected arm as soon as they felt movement in their stroke affected arm. Results. We found that participants with visuospatial inattention (neglect) had impaired kinesthesia 100% of the time, whereas only 59% of participants without neglect were impaired. For those without neglect, we observed that a higher percentage of participants with lower but passing BIT scores displayed impaired kinesthetic behavior (78%) compared with those participants who scored perfect or nearly perfect on the BIT (49%). Conclusions. The presence of visuospatial neglect after stroke is highly predictive of the presence of kinesthetic deficits. However, the presence of kinesthetic deficits does not necessarily always indicate the presence of visuospatial neglect. Our findings highlight the importance of assessment and treatment of kinesthetic deficits after stroke, especially in patients with visuospatial neglect.

Left Neglected is the second neurologically themed novel by Lisa Genova, an American author and neuroscientist based at Harvard University. Genova’s well-received first novel, Still Alice , is a pseudo-memoir of a Harvard University Professor who develops early-onset Alzheimer’s disease. Genova’s book centres on Sarah Nickleson, a 37-year-old vice-president of human resources at an international consulting firm, and her young family. Sarah struggles to juggle the conflicting demands of work and family life. Her life takes a dramatic twist when she overturns her car and sustains a traumatic brain injury, leaving her with profound left visuospatial neglect. The second half of the book documents Sarah’s rehabilitation, including the reappearance of her previously long-term absent mother which forces Sarah to …

[Purpose] This study aimed to investigate the effects of body awareness training (BAT) on mild visuospatial neglect in patients following acute stroke. [Subjects] The subjects were 12 stroke patients randomly assigned to either the experimental group (n1=6) or control group (n2=6). [Methods] The experimental group underwent BAT for 15 minutes and then task-oriented training for 30 minutes a day, five times a week for three weeks. The control group underwent task-oriented training for 30 minutes a day, five times a week for three weeks. Assessments were made using the Motor-free Visual Perception Test (MVPT), Line Bisection Test (LBT), and modified Barthel index (MBI). [Results] Following the interventions, the experimental group showed a significant change in MVPT, LBT, and MBI scores. [Conclusion] The results of this study suggest the feasibility and suitability of BAT with task-oriented training for mild visuospatial neglect in patients with acute stroke.

This practice analysis introduces the Birmingham Cognitive Screen (BCoS), a comprehensive screening tool for stroke survivors including individuals with aphasia and visuospatial neglect. A case study is used to demonstrate how the cognitive profiles created by the multiple-domain assessment at different time points can reduce the need to use multiple standardised assessments to check relative deficits and residual abilities, as well as to guide the rehabilitation process, educate the stroke survivor and family, monitor improvement in impairment and help the therapist to evaluate his or her treatment.

Studies that have investigated prism adaptation (PA) effects on symptoms of visuospatial neglect have primarily used neuropsychological tests as outcome measures. An important question that remains to be answered is whether PA effects translate into improvements in patients' daily life activities. In the present review, we examined systematically the evidence for the effect of PA treatment on daily life activities in patients with neglect. Two authors independently assessed the methodological quality of 25 intervention and 1 follow-up studies using validated scales. PA effects were evaluated for reading/writing, activities of daily living (ADL) direct tests, ADL questionnaires, and navigation tests. Studies were evaluated as being of excellent (n = 1), good (n = 12), fair (n = 10), or poor (n = 3) quality. Among the 26 articles, a total of 32 measurements showed significant PA effects (one measurement from a study of excellent quality, 17 from studies of good quality, 10 from studies of fair quality, four from studies of poor quality), whereas non-significant effects were found in 15 measurements (two from a study of excellent quality, three from studies of good quality, eight from studies of fair quality, two from studies of poor quality). There is some evidence suggesting that PA can improve daily functioning, particularly as measured by reading/writing and ADL direct tests. The impact of several variables on PA effects should be investigated further including sample heterogeneity and time since injury.

On the basis of double dissociations in clinical symptoms of patients with unilateral visuospatial neglect, neuropsychological research distinguishes between different spatial domains (near vs. far) and different spatial reference frames (egocentric vs. allocentric). In this fMRI study, we investigated the neural interaction between spatial domains and spatial reference frames by constructing a virtual three-dimensional world and asking participants to perform either allocentric or egocentric judgments on an object located in either near or far space. Our results suggest that the parietal–occipital junction (POJ) not only shows a preference for near-space processing but is also involved in the neural interaction between spatial domains and spatial reference frames. Two dissociable streams of visual processing exist in the human brain: a ventral perception-related stream and a dorsal action-related stream. Consistent with the perception–action model, both far-space processing and allocentric judgments draw upon the ventral stream whereas both near-space processing and egocentric judgments draw upon the dorsal stream. POJ showed higher neural activity during allocentric judgments (ventral) in near space (dorsal) and egocentric judgments (dorsal) in far space (ventral) as compared with egocentric judgments (dorsal) in near space (dorsal) and allocentric judgments (ventral) in far space (ventral). Because representations in the dorsal and ventral streams need to interact during allocentric judgments (ventral) in near space (dorsal) and egocentric judgments (dorsal) in far space (ventral), our results imply that POJ is involved in the neural interaction between the two streams. Further evidence for the suggested role of POJ as a neural interface between the dorsal and ventral streams is provided by functional connectivity analysis.

Neglect patients are not aware of stimuli in the contralesional space. We aimed to simulate neglect-like behaviour in healthy participants, by asking them to orient their visuospatial attention in two conditions: non-hypnotic suggestion and post-hypnotic suggestion. Results showed that directing visuospatial attention to one side of space caused neglect of stimuli in the opposite side of space, but only when participants were under post-hypnotic suggestion. Furthermore, directing visuospatial attention to the right side of space caused more neglect of left-sided stimuli than directing visuospatial attention to the left side of space did for right-sided stimuli. We propose that post-hypnotic suggestion can be a useful tool for (de)activating neurocognitive mechanisms underlying visuospatial awareness, a function that is fundamental for our survival. The use of post-hypnotic suggestion could be applied to the study of many domains of cognitive neurosciences (e.g., neurocognitive rehabilitation).

Objective: Adaptation to prisms displacing the visual scene rightward is a therapeutic tool for left unilateral spatial neglect (USN). We aimed at comparing the effects of the classic adaptation procedure (repeated pointing toward visual targets, control treatment, C), with those of a novel adaptation method, involving ecological visuomotor activities (experimental treatment, E). Method: In 10 right-brain-damaged USN patients, each treatment was given for 1 week, with a crossover design, for a total of 20 sessions, twice per day. USN was assessed by cancellation, reading, and drawing tasks, and by a standardized scale. Neurological severity was assessed by the National Institutes of Health (NIH) stroke scale (Brott et al., 1989), disability by the Functional Independence Measure (FIM) scale. Results: The 2-week treatments (EC, CE) were equally effective, improving both USN, confirming previous reports (Frassinetti, Angeli, Meneghello, Avanzi, & Làdavas, 2002) and, importantly, disability. The improvement was independent of baseline performance, duration of disease, and neurological severity. Recovery took place after the first week, continued in the second week, and was stable at the follow-up of 3 months. The improvement of USN, measured by cancellation performance, and, in part, that of disability, measured through the FIM scale, were mediated by the size of the leftward aftereffects, suggesting a causal relationship between prism exposure and recovery. The E protocol was better tolerated. Conclusions: Daily life visuomotor activities, associated with prism exposure, are a useful tool for rehabilitating USN patients. This new treatment may widen the compliance with prism exposure treatments and their feasibility within home-based programs.

There is growing evidence that visuospatial neglect (VSN) is associated with lower functional performance in other modalities and is not restricted to the lesioned hemisphere alone, and may also affect the non-lesioned hemisphere in severe first-ever strokes. We aimed to investigate the longitudinal association between the severity of VSN, as reflected by the extent of ipsilesional and contralesional spatial attention deficit, and clinical severity of stroke.This is a secondary data analysis with merged data from two prospective cohort studies. Resulting in 90 patients and 8 longitudinal measurements at 1, 2, 3, 4, 5, 8, 12, and 26 weeks post-stroke onset. A letter cancellation test (LCT) was used as the primary outcome measure to demonstrate presence and severity of VSN. The clinical severity of stroke was classified using the Bamford Classification.No significant association between clinical severity and the number of ipsilesional, as well as contralesional, omissions on the LCT was observed. Recovery of VSN at the contralesional hemiplegic, as well as ipsilesional non-hemiplegic side, was only dependent on 'time' as a reflection of spontaneous neurobiological recovery post-stroke. The recovery of the ipsilesional extension of VSN was significantly slower for the total anterior circulation infarct (TACI) group compared to the non-TACI group.Larger strokes have a significant negative impact on recovery of visual attention at the non-hemiplegic side. No clinical determinants that regulate spontaneous time-dependent recovery of VSN were found. While early 'stroke severity' has been regarded as a strong predictor of functional outcome at a group level, other prognostic factors (demographic, stroke related) need to be determined.EXPLICIT-stroke Trial: http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1424 Stroke Intensity Trial: http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1665.

The contralesional line bisection error in hemianopia is a well-known clinical phenomenon. Its origin, however, is still unclear. We therefore investigated the causes of the hemianopic bisection error in 84 patients with unilateral homonymous hemianopia without visuospatial neglect. Our results suggest that the contralesional bisection error is neither a consequence of the visual field defect itself nor a manifestation of strategic adaptation of attention and eye movements into contralesional hemispace. Additional extrastriate brain injury, presumably to occipito-temporal areas including the occipital white matter, seems to be critical for the emergence of the contralesional bisection error that is frequently associated with but separable from homonymous hemianopia.

Aim: The study aims to describe the epidemiology and the neural correlates of peripersonal visuospatial neglect (PVN) in patients admitted to the Geneva Stroke Unit for an acute stroke or a transient ischemic attack (TIA). Methods: Eligible subjects were tested for PVN using both the Ota's discriminative cancellation task and a line bisection task. Brain lesions were identified on diffusion-weighted imaging. A multivariate analysis was performed to identify risk factors of PVN. Results: Ninety-eight consecutive patients (40.8% females) were recruited: 64 cases of ischemic stroke, 9 cases of hemorrhagic stroke and 25 cases of TIAs. The mean age was 61.9 ± 2.86 years. The incidence of PVN was 23.5% (95% CI 15.5-33.1) and was not significantly different between patients with right and left hemisphere stroke. There were 5 cases of ipsilesional neglect. There was no association between PVN and age, sex, stroke severity, handedness, lesion type, lesion volume and time to first examination. Lesions of temporal and parietal lobes were the most frequent in patients with PVN. Conclusion: PVN has a low incidence in the acute stroke settings and there is no particular predictor of its presence. It is most often associated with temporo-parietal lesions.

Objective Contraversive pushing (CP) is a neurologic disorder characterized by a lateral postural imbalance. Pusher patients actively push toward their contralesional side due to a misperception of the body's orientation in relation to gravity. Although not every patient with CP suffers from spatial neglect (SN), both phenomena are highly correlated in right-hemispheric patients. The present study investigates whether peripersonal visuospatial functioning differs in neglect patients with versus without CP (NP+ vs. NP- patients). Method Eighteen right-hemispheric stroke patients with SN were included, of which 17 in a double-blind case-control study and 1 single case with posterior pushing to supplement the discourse. A computer-based visuospatial navigation task, in which lateralized deviation can freely emerge, was used to quantify visuospatial behavior. In addition, visuospatial orienting was monitored using line bisection. Results Significant intergroup differences were found. The NP+ patients demonstrated a smaller ipsilesional navigational deviation and more cross-over (contralesional instead of ipsilesional deviation) in long line bisection. As such, they demonstrated a contraversive (contralesionally directed) shift in comparison with the NP- patients. Conclusions These findings highlight the similarity between 2 systems of space representation. They are consistent with a coherence between the neural processing system that mainly provides for postural control, and the one responsible for nonpredominantly postural, visuospatial behavior.

[Purpose] To investigate the effects of a combination of transcranial direct current stimulation (tDCS) and feedback training (FT) on subacute stroke patients with unilateral visuospatial neglect. [Subjects] The subjects were randomly assigned to a tDCS + FT group (n=6) and a FT group (n=6). [Methods] Patients in the tDCS + FT group received tDCS for 20 minutes and then received FT for 30 minutes a day, 5 days a week for 3 weeks. The control group received FT for 30 minutes a day, 5 days a week for 3 weeks. [Results] After the intervention, both groups showed significant improvements in the Motor-Free Visual Perception Test (MVPT), line bisection test (LBT), and modified Barthel index (MBI) over the baseline results. The comparison of the two groups after the intervention revealed that the rDCS + FT group showed more significant improvements in MVPT, LBT, and MBI. [Conclusion] The results of this study suggest that tDCS combined with FT has a positive effect on unilateral visuospatial neglect in patients with subacute stroke.

When neurologically normal individuals bisect a horizontal line as accurately as possible, they reliably show a slight leftward error. This leftward inaccuracy is called pseudoneglect because errors made by neurologically normal individuals are directionally opposite to those made by persons with visuospatial neglect (Jewell & McCourt, 2000). In the current study, normal right-handed observers bisected horizontal lines that were altered to bias line length judgments either toward the right or the left side of the line. Non-target dots were placed on or near the line stimuli using principles derived from a theory of visual illusions of length called centroid extraction (Morgan, Hole, & Glennerster, 1990). This theory argues that the position of a visual target is calculated as the mean position of all stimuli in close proximity to the target stimulus. We predicted that perceptual alterations that shifted the direction of centroid extraction would also shift the direction of line bisection errors. Our findings confirmed this prediction and support the idea that both perceptual and attentional factors contribute to the pseudoneglect effect.

Six patients with visuospatial neglect following right hemisphere lesions were given three tasks that assessed performance in areas of space ranging from extreme left to extreme right. A line bisection task required the patients to detect and bisect lines of four different lengths at seven left-right spatial locations, a number report task required the patients to name 11 two-digit numbers in a left-right array, and a tiling task required patients to place small black tiles over the black squares of a grid that stretched from 65 degrees left to 65 degrees right. Performance was compared with that of 20 age-matched controls. The patients showed the characteristic signs of left-side neglect in left space, extending to the central midline. Performance was relatively normal in centre-right space but all 6 patients showed signs of neglect of extreme right space (60 degrees to the right of the midline and beyond). We propose that neglect is best characterised as a bilateral, asymmetrical compression of experienced space in which the constriction extends further from the left than from the right but nevertheless affects both sides of space.

Figure copying is often used to detect visuospatial neglect (VSN) in brain-damaged patients. We describe algorithms that enable the computation of parameters for describing figure-copying performance. The researcher can readily implement these algorithms on a computer using image analysis software, and they provide information on goodness-of-fit, relative to a standard model, as well as on dynamic aspects of subjects' performance in completing figure copies. To demonstrate the clinical utility of these algorithms, preliminary results from a group of right-hemisphere brain-damaged patients, some of whom have VSN, are compared with those for age-matched controls.

The temporary improvement of visuospatial neglect during galvanic vestibular stimulation (Scand. J. Rehabil. Med. 31 (1999)117) may result from correction of the spatial reference frame distorted by the responsible lesion. Prior to an investigation of the neural basis of this effect in neurological patients, exploration of the neural mechanisms underlying such procedures in normals is required to provide insight into the physiological basis thereof. Despite their clinical impact, the neural mechanisms underlying the interaction of galvanic (and other) vestibular manipulations with visuospatial processing (and indeed the neural bases of how spatial reference frames are computed in man) remain to be clarified. We accordingly used fMRI in normal volunteers to investigate the effect of galvanically induced interference with the egocentric spatial reference frame on the neural processes underlying allocentric visuospatial (line bisection) judgments. A significant specific interaction of galvanic vestibular stimulation with the neural mechanisms underlying allocentric visuospatial judgments was observed in right posterior parietal and ventral premotor cortex only. Activation of these areas previously found to be damaged in visuospatial neglect suggests that these effects reflect the increased processing demands when compensating for the distorted egocentric spatial reference frame while maintaining accurate performance during the allocentric spatial task. These results thus implicate right posterior parietal and right ventral premotor cortex in the computation of spatial reference frames. Furthermore, our data imply a specific physiological basis for the temporary improvement of visuospatial neglect in patients with right hemisphere lesions during galvanic vestibular stimulation and may thus impact upon the rehabilitation of neglect: understanding the interaction of galvanic vestibular stimulation with allocentric visuospatial judgments in healthy volunteers may lead to the more effective deployment of such techniques in neurological patients.