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Animal and human literature supports spatial-motor "Aiming" bias, a frontal-subcortical syndrome, as a core deficit in spatial neglect. However, spatial neglect treatment studies rarely assess Aiming errors. Two knowledge gaps result: spatial neglect rehabilitation studies fail to capture the impact on motor-exploratory aspects of functional disability. Also, across spatial neglect treatment studies, discrepant treatment effects may also result from sampling different proportions of patients with Aiming bias. We review behavioural evidence for Aiming spatial neglect, and demonstrate the importance of measuring and targeting Aiming bias for treatment, by reviewing literature on Aiming spatial neglect and prism adaptation treatment, and presenting new preliminary data on bromocriptine treatment. Finally, we review neuroanatomical and network disruption that may give rise to Aiming spatial neglect. Because Aiming spatial neglect predicts prism adaptation treatment response, assessment may broaden the ability of rehabilitation research to capture functionally-relevant disability. Frontal brain lesions predict both the presence of Aiming spatial neglect, and a robust response to some spatial neglect interventions. Research is needed that co-stratifies spatial neglect patients by lesion location and Aiming spatial neglect, to personalize spatial neglect rehabilitation and perhaps even open a path to spatial retraining as a means of promoting better mobility after stroke.

Background and Purpose: Delirium, an acute reduction in cognitive functioning, hinders stroke recovery and contributes to cognitive decline. Right-hemisphere stroke is linked with higher delirium incidence, likely, due to the prevalence of spatial neglect (SN), a right-brain disorder of spatial processing. This study tested if symptoms of delirium and SN after right-hemisphere stroke are associated with abnormal function of the right-dominant neural networks specialized for maintaining attention, orientation, and arousal. Methods: Twenty-nine participants with right-hemisphere ischemic stroke undergoing acute rehabilitation completed delirium and SN assessments and functional neuroimaging scans. Whole-brain functional connectivity of 4 right-hemisphere seed regions in the cortical-subcortical arousal and attention networks was assessed for its relationship to validated SN and delirium severity measures. Results: Of 29 patients, 6 (21%) met the diagnostic criteria for delirium and 16 (55%) for SN. Decreased connectivity of the right basal forebrain to brain stem and basal ganglia predicted more severe SN. Increased connectivity of the arousal and attention network regions with the parietal, frontal, and temporal structures in the unaffected hemisphere was also found in more severe delirium and SN. Conclusions: Delirium and SN are associated with decreased arousal network activity and an imbalance of cortico-subcortical hemispheric connectivity. Better understanding of neural correlates of poststroke delirium and SN will lead to improved neuroscience-based treatment development for these disorders. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03349411.

Objective To derive and validate a comorbidity-based delirium risk index (DRI) to predict postoperative delirium. Data source/study setting Data of 506 438 hip fracture repair surgeries from 2006 to 2016 were collected to derive DRI and perform internal validation from the Premier Healthcare Database, which provided billing information on 20-25 percent of hospitalizations in the USA. Additionally, data of 1 130 569 knee arthroplasty surgeries were retrieved for external validation. Study design Thirty-six commonly seen comorbidities were evaluated by logistic regression with the outcome of postoperative delirium. The hip fracture repair surgery cohort was separated into a training dataset (60 percent) and an internal validation (40 percent) dataset. The least absolute shrinkage and selection operator (LASSO) procedure was applied for variable selection, and weights were assigned to selected comorbidities to quantify corresponding risks. The newly developed DRI was then compared to the Charlson-Deyo Index for goodness-of-fit and predictive ability, using the Akaike information criterion (AIC), Bayesian information criterion (BIC), area under the ROC curve (AUC) for goodness-of-fit, and odds ratios for predictive performance. Additional internal validation was performed by splitting the data by four regions and in 4 randomly selected hospitals. External validation was conducted in patients with knee arthroplasty surgeries. Data collection Hip fracture repair surgeries, knee arthroplasty surgeries, and comorbidities were identified by using ICD-9 codes. Postoperative delirium was defined by using ICD-9 codes and analyzing billing information for antipsychotics (specifically haloperidol, olanzapine, and quetiapine) typically recommended to treat delirium. Principal findings The derived DRI includes 14 comorbidities and assigns comorbidities weights ranging from 1 to 6. The DRI outperformed the Charlson-Deyo Comorbidity Index with better goodness-of-fit and predictive performance. Conclusions Delirium risk index is a valid comorbidity index for covariate adjustment and risk prediction in the context of postoperative delirium. Future work is needed to test its performance in different patient populations and varying definitions of delirium.

Objectives: Free Water Protocols (FWPs) are implemented selectively because of mixed evidence on the benefits associated with their use. This retrospective study examines the implementation a long-standing clinical program and descriptively reports rehabilitation and quality care outcomes. Methods: Data were collected over 6 years (n = 575). Inpatient rehabilitation setting. Variables included in this study were age, medical diagnoses, rate of acute care hospital transfers, discharge destinations, length of time on FWP. Results: Cohort consisted of older adults (M = 68.43, SD = 15.11), with diagnosis of stroke (60.2%), brain injury (19.1%), spinal cord injury (7.3%), cardiac (1%), orthopedics (5%), other (13.1%). Acute care hospital transfers occurred in 6% as descriptively compared to national average (14%). Additionally, participants tolerated FWP for days (M = 14.1, SD = 14.4) and most went home following rehabilitation Discussion: This retrospective study concludes the feasibility of implementing a FWP in a rehabilitation facility and reports descriptive outcomes. Experimental research is required for conclusions to be made regarding effectiveness of the FWP for dysphagia.

OBJECTIVE: This study examined lexical and neuroanatomic correlates of reading errors in individuals with spatial neglect, defined as a failure to respond to stimuli in the side of space opposite a brain lesion, causing functional disability. METHOD: One hundred and ten participants with left spatial neglect after right-hemisphere stroke read aloud a list of 36 words. Reading errors were scored as “contralesional” (error in the left half of the word) or as “other”. The influence of lexical processing on neglect dyslexia was studied with a stepwise regression using word frequency, orthographic neighborhood (number of same length neighbors that differ by 1 letter), bigram and trigram counts (number of words with the same 2- and 3-letter combinations), length, concreteness, and imageability as predictors. MRI/CT images of 92 patients were studied in a voxelwise lesion-symptom analysis (VLSM). RESULTS: Longer length and more trigram neighbors increased, while higher concreteness reduced, the rate of contralesional errors. VLSM revealed lesions in the inferior temporal sulcus, middle temporal and angular gyri, precuneus, temporal pole, and temporo-parietal white matter associated with the rate of contralesional errors. CONCLUSIONS: Orthographic competitors may decrease word salience, while semantic concreteness may help constrain the selection of available word options when it is based on degraded information from the left side of the word. PUBLIC SIGNIFICANCE STATEMENT: Reading impairments arising after stroke represent a devastating problem, restricting an individual’s life participation, independence and quality of life. In this study, we examined reading impairments in neglect dyslexia, a symptom characterized by reading errors in the half of the word opposite a brain lesion. To help improve the current understanding of this symptom, we identified specific word characteristics and stroke locations that are associated with increased rates of neglect dyslexia reading errors.

Background: Health-related quality of life (HRQOL) is a construct of quality of life relevant to health. HRQOL can be measured multiple ways including self-perceived interpretation of one’s health status. Research has shown value in understanding self-perceived or person-centered HRQOL. Thus, these types of assessments have been integrated into health care systems, used to help patients set personal goals and to determine treatment success. The purpose of this study was to describe the group, examine the relationship between HRQOL and functional independence, and then determine the impact of standard care on the HRQOL (index and visual analog scale [VAS]).Methods: Retrospective clinical observation study. Descriptive statistics used to describe the stroke sample. Comparison was performed to explore the correlation between the EuroQol 5-Dimensions Questionnaire (EQ-5D) and the Functional Independence Measure (FIM) at admission and discharge. Paired-samples t-test was conducted to evaluate the impact of standard therapy on HRQOL on EQ-5D.Results: n=1325; mean age of 72 years (SD=13.28) and 65% females. A weak, positive correlation found at admission (r=.15, n=1325, p

INTRODUCTION: Delirium is well studied in the acute care setting, but there is limited understanding of its impact in the post-acute care setting, particularly in the inpatient rehabilitation facility (IRF). OBJECTIVE: To investigate the prevalence and related outcomes of delirium in the IRF setting, particularly patients’ transfers to acute care hospitals. DESIGN: Retrospective cohort study SETTING: A freestanding IRF PARTICIPANTS: Patients discharged from an IRF between January 2016 and December 2016 (12 months) INTERVENTIONS: Not applicable MAIN OUTCOME MEASURES: Transfer to acute care hospitals, motor and cognitive Functional Independence Measures (FIM), length of stay, discharge disposition RESULTS: A total of 1,567 patients (53.86% female, mean age 72.86 +/− 13.9) were included in the analysis. Positive scores were found among 142 (9.1%) patients on a 3-Minute Diagnostic Interview for Confusion Assessment Method (3D-CAM), indicating delirium on admission. Fifty-nine (3.8%) were un-scorable on 3D-CAM. Twice as many delirium patients were transferred to acute care hospitals compared to non-delirium patients (22.5% versus 10.8%, P

Objective: To determine whether prism adaptation treatment (PAT) integrated into the standard of care improves rehabilitation outcome in patients with spatial neglect (SN). Design: Retrospective matched control study based on information extracted from June 2017-September 2019. Setting: Inpatient rehabilitation. Participants: Patients from 14 rehabilitation hospitals scoring >0 on the Catherine Bergego Scale (N=312). The median age was 69.5 years, including 152 (49%) female patients and 275 (88%) patients with stroke. Interventions: Patients were matched 1:1 by age (±5 years), FIM score at admission (±2 points), and SN severity using the Catherine Bergego Scale (±2 points) and classified into 2 groups: treated (8-12 daily sessions of PAT) vs untreated (no PAT). Main Outcome Measures: FIM and its minimal clinically important difference (MCID) were the primary outcome variables. Secondary outcome was home discharge. Results: Analysis included the 312 matched patients (156 per group). FIM scores at discharge were analyzed using repeated-measures analyses of variance. The treated group showed reliably higher scores than the untreated group in Total FIM, F=5.57, P=.020, partial η2=0.035, and Cognitive FIM, F=19.20, P

Better understanding of cerebral blood flow (CBF) perfusion in stroke recovery can help inform decisions about optimal timing and targets of restorative treatments. In this study, we examined the relationship between cerebral perfusion and recovery from stroke‐induced reading deficits. Left stroke patients were tested with a noninvasive CBF measure (arterial spin labeling) 3 months post‐stroke. We measured blood flow perfusion within the left and right sides of the brain, in areas surrounding the lesion, and areas belonging to the reading network. Two hypotheses were tested. The first was that recovery of reading function depends on increased perfusion around the stroke lesion. This hypothesis was not supported by our findings. The second hypothesis was that increased perfusion of intact areas within the reading circuit is tightly coupled with recovery. Our findings are consistent with this hypothesis. Specifically, higher perfusion in the left reading network measured during the subacute stroke period predicted better reading ability and phonology competence in the chronic period. In contrast, higher perfusion of the right homologous regions was associated with decreased reading accuracy and phonology competence in the subacute and chronic periods. These findings suggest that recovery of reading and language competence may rely on improved blood flow in the reading network of the language‐dominant hemisphere.

ObjectiveTo evaluate the effect of intensive rehabilitation on the modified Rankin Scale (mRS), a measure of activities limitation commonly used in acute stroke studies, and to define the specific changes in body structure/function (motor impairment) most related to mRS gains.MethodsPatients were enrolled >90 days poststroke. Each was evaluated before and 30 days after a 6-week course of daily rehabilitation targeting the arm. Activity gains, measured using the mRS, were examined and compared to body structure/function gains, measured using the Fugl-Meyer (FM) motor scale. Additional analyses examined whether activity gains were more strongly related to specific body structure/function gains.ResultsAt baseline (160 ± 48 days poststroke), patients (n = 77) had median mRS score of 3 (interquartile range, 2–3), decreasing to 2 [2–3] 30 days posttherapy (p < 0.0001). Similarly, the proportion of patients with mRS score ≤2 increased from 46.8% at baseline to 66.2% at 30 days posttherapy (p = 0.015). These findings were accounted for by the mRS score decreasing in 24 (31.2%) patients. Patients with a treatment-related mRS score improvement, compared to those without, had similar overall motor gains (change in total FM score, p = 0.63). In exploratory analysis, improvement in several specific motor impairments, such as finger flexion and wrist circumduction, was significantly associated with higher likelihood of mRS decrease.ConclusionsIntensive arm motor therapy is associated with improved mRS in a substantial fraction (31.2%) of patients. Exploratory analysis suggests specific motor impairments that might underlie this finding and may be optimal targets for rehabilitation therapies that aim to reduce activities limitations.Clinical TrialClinicaltrials.gov identifier: NCT02360488.Classification of EvidenceThis study provides Class III evidence that for patients >90 days poststroke with persistent arm motor deficits, intensive arm motor therapy improved mRS in a substantial fraction (31.2%) of patients.

Spatial neglect after right brain stroke affects balance, and improvements in sitting balance after prism adaptation have been demonstrated using short-duration center of pressure (CoP) data. We present long-duration (5 min) CoP and trunk muscles electromyography recordings of a 61-year-old man with left-sided spatial neglect, before and after a single session of prism adaptation. His CoP-derived measures showed improved balance and postural stability in both the anterior-posterior and medial-lateral directions after prism adaptation. Concurrently, asymmetry in neuromuscular activations was reduced. The findings suggest that improved sitting balance may be associated with more symmetrical activation of trunk muscles after prism adaptation.

The identification of brain tumor type, shape, and size from MRI images plays an important role in glioma diagnosis and treatment. Manually identifying the tumor is time expensive and prone to error. And while information from different image modalities may help in principle, using these modalities for manual tumor segmentation may be even more time consuming. Convolutional U-Net architectures with encoders and decoders are state of the art in automated methods for image segmentation. Often only a single encoder and decoder is used, where different modalities and regions of the tumor share the same model parameters. This may lead to incorrect segmentations. We propose a convolutional U-Net that has separate, independent encoders for each image modality. The outputs from each encoder are concatenated and given to separate fusion and decoder blocks for each region of the tumor. The features from each decoder block are then calibrated in a final feature fusion block, after which the model gives it final predictions. Our network is an end-to-end model that simplifies training and reproducibility. On the BraTS 2019 validation dataset our model achieves average Dice values of 0.75, 0.90, and 0.83 for the enhancing tumor, whole tumor, and tumor core subregions respectively.

Brain tumor classification plays an important role in brain cancer diagnosis and treatment. Pathologists typically have to work through numerous pathology images that can be in the order of hundreds or thousands which takes time and is prone to manual error. Here we investigate automating this task given pathology images as well as 3D MRI volumes without lesion maps. We use data provided by the CPM-RadPath 2019 MICCAI challenge. We first evaluate accuracy on the validation dataset with MRI and pathology images separately. We predict the 3D tumor mask with our custom developed tumor segmentation model that we used for the BraTS 2019 challenge. We show that the predicted tumor segmentations give a higher validation accuracy of 77.1% vs. 69.8% with MRI images when trained by a 3D residual convolutional neural network. For pathology images we train a 2D residual network and obtain a 66.2% validation accuracy. In both cases we find high training accuracies above 95% which suggests overfitting. We propose a dual path residual convolutional neural network model that trains simultaneously from both MRI and pathology images and we use a simple method to prevent overfitting. One path of our network is fully 3D and considers 3D tumor segmentations as input while the other path considers pathology images. To prevent overfitting we stop training after 90% training accuracy at the epoch number where our network loss increases in the following one. With this approach we achieve a validation accuracy of 84.9% showing that indeed combining the two image sources yields a better overall accuracy.

OBJECTIVE Spatial neglect (SN) constitutes a substantial barrier to functional recovery after acquired brain injury. However, because of its multimodal nature, no single test can capture all the signs of SN. To provide a clinically feasible solution, we used conventional neuropsychological tests as well as the Catherine Bergego Scale (CBS) via the Kessler Foundation Neglect Assessment Process (KF-NAP). The goal was to add evidence that a global approach should detect better even subtle signs of SN. METHOD Fourteen individuals with lesions located in the right cerebral hemisphere participated in the study. Participants were assessed with a comprehensive battery of neuropsychological tests, comprising a set of visuospatial tests to evaluate several spatial domains. In addition, patients underwent functional assessment with the Barthel Index, the Functional Independence Measure (FIM), and the CBS via KF-NAP. RESULTS The CBS via KF-NAP was associated with the visuospatial paper-based tests (p = .004) as well as the Motor FIM (p = .003), and was more sensitive than the Behavioral Inattention Test-Conventional in detecting SN (p = .014). CONCLUSIONS We showed that the CBS via KF-NAP was able: (a) to detect functional impairment, especially motor, related to SN; (b) to selectively measures spatial rather than nonspatial dysfunctions; and (c) to be highly sensitive in detecting SN signs especially in those patients with mild severity, covering several aspects of SN manifestations. The patient's SN diagnosis based on the CBS via KF-NAP is clinically important and directly relevant to care planning and goal setting. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

BACKGROUND: Intensive, adaptable and engaging telerehabilitation is needed to enhance recovery and maximize outcomes. Such services may be provided under early supported discharge, or later for chronic populations. A novel virtual reality game-based telerehabilitation system was designed for individuals post-stroke to enhance their bimanual upper extremity motor function, cognition, and wellbeing. OBJECTIVES: To evaluate the feasibility of novel therapeutic game controller and telerehabilitation system for home use. METHODS: Individuals chronic post-stroke and their caregivers were recruited (n=8+8) for this feasibility study. One was a screen failure and seven completed four weeks (20 sessions) of home-based therapy with or without remote monitoring. Standardized clinical outcome measures were taken pre- and post-therapy. Game performance outcomes were sampled at every session, while participant and caregiver subjective evaluations were done weekly. RESULTS: There was a 96% rate of compliance to protocol, resulting in an average of 13,000 total arm repetitions/week/participant. Group analysis showed significant (p < 0.05) improvements in grasp strength (effect size [ES] = 0.15), depression (Beck Depression Inventory II, ES = 0.75), and cognition (Neuropsychological Assessment Battery for Executive Function, ES = 0.46). Among the 49 outcome variables, 36 variables (73.5%) improved significantly (p = 0.001, binomial sign test). Technology acceptance was very good with system rating by participants at 3.7/5 and by caregivers at 3.5/5. CONCLUSIONS: These findings indicate the feasibility and efficacy of the system in providing home-based telerehabilitation. The BrightBrainer system needs to be further evaluated in randomized control trials and with individuals early post-stroke.

Spatial neglect is a disorder of attention, perception, and processing of stimuli in contralesional space. The heterogeneous behaviors involve diverse neuroanatomical mechanisms. Anecdotal evidence suggests that neural circuitry of active spatial perception may differ from that used to encode spatial memory. These differences can escape detection by conventional assessments, thereby leading to missed diagnoses. We present a case, in an artist who demonstrates selective impairment in a contralesional space during active Where spatial perception. His performance is better when asked to draw entirely from memory. This case highlights the variability in neglect, importance for comprehensive testing, and encourages further investigation.

Purpose Patching for double vision is a common palliative treatment for head-trauma patients with acquired strabismus when prisms are not feasible. Methods We review literature on spatial neglect and discuss possible effects of monocular occlusion on spatial attention. Results Patching the left eye has been shown to worsen spatial judgments in some brain-injured patients with left neglect by inhibiting the right superior colliculus further impairing contralateral leftward orienting (the Sprague Effect). Conclusions Because more peripheral parts of the visual field increasingly project to the contralateral superior colliculus with the temporal crescent being entirely contralateral, avoiding patching of the temporal crescent was advised, and in most cases can be achieved by taping off the spectacle lens and avoiding an elastic eye patch.

OBJECTIVES Poststroke delirium may be underdiagnosed due to the challenges of disentangling delirium symptoms from underlying neurologic deficits. We aimed to determine the prevalence of individual delirium features and the frequency with which they could not be assessed in patients with intracerebral hemorrhage. DESIGN Prospective observational cohort study. SETTING Neurocritical Care and Stroke Units at a university hospital. PATIENTS Consecutive patients with intracerebral hemorrhage from February 2018 to May 2018. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS An attending neurointensivist performed 257 total daily assessments for delirium on 60 patients (mean age 68.0 [SD 18.4], 62% male, median intracerebral hemorrhage score 1.5 [interquartile range 1-2], delirium prevalence 57% [n = 34]). Each assessment included the Confusion Assessment Method for the ICU, Intensive Care Delirium Screening Checklist, a focused bedside cognitive examination, chart review, and nurse interview. We characterized individual symptom prevalence and established delirium diagnoses using Diagnostic and Statistical Manual of Mental Disorders, fifth edition criteria, then compared performance of the Confusion Assessment Method for the ICU and Intensive Care Delirium Screening Checklist against reference-standard expert diagnosis. Symptom fluctuation (61% of all assessments), psychomotor changes (46%), sleep-wake disturbances (46%), and impaired arousal (37%) had the highest prevalence and were never rated "unable to assess," while inattention (36%), disorientation (27%), and disorganized thinking (18%) were also common but were often rated 'unable to assess' (32%, 43%, and 44% of assessments, respectively), most frequently due to aphasia (32% of patients). Including nonverbal assessments of attention decreased the frequency of 'unable to assess' ratings to 11%. Since the Intensive Care Delirium Screening Checklist may be positive without the presence of symptoms that require verbal assessment, it was more accurate (sensitivity = 77%, specificity = 97%, area under the receiver operating characteristic curve, 0.87) than the Confusion Assessment Method for the ICU (sensitivity = 41%, specificity = 88%, area under the receiver operating characteristic curve, 0.64). CONCLUSIONS Delirium is common after intracerebral hemorrhage, but severe neurologic deficits may confound its assessment and lead to underdiagnosis. The Intensive Care Delirium Screening Checklist's inclusion of nonverbal features may make it more accurate than the Confusion Assessment Method for the ICU in patients with neurologic deficits, but novel tools designed for such patients may be warranted.

Spasticity or increase in muscle tone presents challenges during post-stroke rehabilitation. The use of off-the-shelf game controllers is problematic for individuals with hand spasticity. The novel BrightBrainer Grasp (BBG) controller was designed to overcome these barriers when used in virtual rehabilitation of individuals post-stroke. The custom controller measures power grasp, finger extension, wrist position and orientation, as well as 3D hand position. It is designed to minimize friction when used by those with no gravity bearing. Two controllers were used in bilateral training. This paper presents a detailed description of the BBG controllers and their interaction with the BrightBrainer™ gaming system. Two case reports of individuals chronic post-stroke who participated in a 4-week telerehabilitation intervention are included.

Highlights • Time and effort for hand-segmenting lesions bottlenecks brain lesion-deficit studies. • We provide a fully-automated tool for stroke brain lesion segmentation. • This tool significantly outperforms existing techniques, including on small lesions. • Freely available tool should accelerate progress in brain lesion-deficit studies., Automatic identification of brain lesions from magnetic resonance imaging (MRI) scans of stroke survivors would be a useful aid in patient diagnosis and treatment planning. It would also greatly facilitate the study of brain-behavior relationships by eliminating the laborious step of having a human expert manually segment the lesion on each brain scan. We propose a multi-modal multi-path convolutional neural network system for automating stroke lesion segmentation. Our system has nine end-to-end UNets that take as input 2-dimensional (2D) slices and examines all three planes with three different normalizations. Outputs from these nine total paths are concatenated into a 3D volume that is then passed to a 3D convolutional neural network to output a final lesion mask. We trained and tested our method on datasets from three sources: Medical College of Wisconsin (MCW), Kessler Foundation (KF), and the publicly available Anatomical Tracings of Lesions After Stroke (ATLAS) dataset. To promote wide applicability, lesions were included from both subacute (1 to 5 weeks) and chronic ( > 3 months) phases post stroke, and were of both hemorrhagic and ischemic etiology. Cross-study validation results (with independent training and validation datasets) were obtained to compare with previous methods based on naive Bayes, random forests, and three recently published convolutional neural networks. Model performance was quantified in terms of the Dice coefficient, a measure of spatial overlap between the model-identified lesion and the human expert-identified lesion, where 0 is no overlap and 1 is complete overlap. Training on the KF and MCW images and testing on the ATLAS images yielded a mean Dice coefficient of 0.54. This was reliably better than the next best previous model, UNet, at 0.47. Reversing the train and test datasets yields a mean Dice of 0.47 on KF and MCW images, whereas the next best UNet reaches 0.45. With all three datasets combined, the current system compared to previous methods also attained a reliably higher cross-validation accuracy. It also achieved high Dice values for many smaller lesions that existing methods have difficulty identifying. Overall, our system is a clear improvement over previous methods for automating stroke lesion segmentation, bringing us an important step closer to the inter-rater accuracy level of human experts.

PURPOSE OF REVIEW: Spatial neglect is asymmetric orienting and action after a brain lesion, causing functional disability. It is common after a stroke; however, it is vastly underdocumented and undertreated. This article addresses the implementation gap in identifying and treating spatial neglect, to reduce disability and improve healthcare costs and burden. RECENT FINDINGS: Professional organizations published recommendations to implement spatial neglect care. Physicians can lead an interdisciplinary team: functionally relevant spatial neglect assessment, evidence-based spatial retraining, and integrated spatial and vision interventions can optimize outcomes. Research also strongly suggests spatial neglect adversely affects motor systems. Spatial neglect therapy might thus “kick-start” rehabilitation and improve paralysis recovery. SUMMARY: Clinicians can implement new techniques to detect spatial neglect and lead interdisciplinary teams to promote better, integrated spatial neglect care. Future studies of brain imaging biomarkers to detect spatial neglect, and real-world applicability of prism adaptation treatment, are needed.

The right brain critically mediates a number of fundamental cognitive functions. In this chapter, we review the definitions and history, pathophysiology and neuroanatomy, clinical presentation, and approach to rehabilitation of four major cognitive syndromes associated with right brain injury. Although these disorders can occur in other neurological disorders, stroke is the most common setting to observe disabling spatial neglect, anosognosia for hemiplegia, emotional processing disorder, including emotional aprosodia, and alien hand syndrome (callosal and posterior types). We urge physicians, nurses, psychologists and therapists to incorporate rehabilitation of right brain stroke syndrome into acute and chronic rehabilitation plans. Better identification and treatment of right brain stroke may reduce the significant long-term disability associated with these cognitive problems, and may improve poststroke family and community reintegration.

Spatial neglect is asymmetric attention, orienting, and action causing functional disability. It is linked to higher-order cortical sensory processing; however, spatial motor “Aiming” processing is critical to fundamental, adaptive environmental movement and daily life function. The cingulate cortex, in particular the anterior cingulate and anterior midcingulate cortex, is strongly linked to spatial Aiming deficits and likely to predict daily life disability in spatial neglect. The authors review the impact and mechanisms of spatial neglect and then describe specific symptoms associated with spatial neglect that are theoretically linked to cingulate cortical functions or associated with lesions extending to cingulate regions in a well-characterized spatial neglect cohort. The treatment implications for a link between cingulate cortex spatial Aiming neglect and therapies that improve spatial action, arousal, and persistence are discussed. Clinicians may want to consider theoretically motivated treatments targeted at specific symptoms as well as use treatments supported for spatial neglect based on unselected and uncharacterized groups.

OBJECTIVE: To characterize the mediation of attention and action in space following traumatic brain injury (TBI). METHOD: Two exploratory analyses were performed to determine the influence of spatial 'Aiming' motor versus spatial 'Where' bias on line bisection in TBI participants. The first experiment compared performance according to severity and location of injury in TBI. The second experiment examined bisection performance in a larger TBI sample against a matched control group. In both experiments, participants bisected lines in near and far space using an apparatus that allowed for the fractionation of spatial Aiming versus Where error components. RESULTS: In the first experiment, participants with severe injuries tended to incur rightward error when starting from the right in far space, compared with participants with mild injuries. In the second experiment, when performance was examined at the individual level, more participants with TBI tended to incur rightward motor error compared to controls. CONCLUSIONS: TBI may cause frontal-subcortical cognitive dysfunction and asymmetric motor perseveration, affecting spatial Aiming bias on line bisection. Potential effects on real-world function need further investigation. (PsycINFO Database Record(c) 2016 APA, all rights reserved). Language: en

Emerging research suggests spatial neglect after right stroke is linked to dysfunctional attention and motor networks. Advanced functional connectivity analysis clarified brain network recovery, however we need to know how networks participate in adaptive motor performance. We need to verify network changes associated with validated functional measures and spatial-motor performance in spatial neglect, especially in patients with large brain lesions and significant disability. This study tested whether disability-relevant spatial neglect associates with different patterns of resting state functional connectivity between motor, dorsal and ventral attention networks (MN, DAN and VAN). Right stroke patients had spatial neglect (n = 8) or not (n = 10) on the Behavioural Inattention Test-conventional. Spatial neglect patients had weaker intranetwork VAN connectivity, and reduced internetwork connectivity between VAN and left frontal eye field (DAN), and between VAN and the left primary motor area (MN). These network impairments might explain the co-occurrence of attention and motor deficits in spatial neglect, and open a path to assessing functional connectivity in clinical trials of combined spatial retraining and motor rehabilitation after stroke.

Spatial neglect commonly follows right hemisphere stroke. It is defined as impaired contralesional stimulus detection, response, or action, causing functional disability. While prism adaptation treatment is highly promising to promote functional recovery of spatial neglect, not all individuals respond. Consistent with a primary effect of prism adaptation on spatial movements, we previously demonstrated that functional improvement after prism adaptation treatment is linked to frontal lobe lesions (Chen, Goedert, Shah, Foundas, & Barrett, 2014). However, that study was a treatment-only study with no randomized control group. The current study randomized individuals with spatial neglect to receive ten days of prism adaptation treatment, or to receive only standard care (control group). Replicating our earlier results, we found that the presence of frontal lesions moderated response to prism adaptation treatment: Among prism-treated patients, only those with frontal lesions demonstrated functional improvements in their neglect symptoms. Conversely, among individuals in the standard-care control, the presence of frontal lesions did not modify recovery. These results suggest that further research is needed on how frontal lesions may predict response to prism adaptation treatment. Additionally, the results help elucidate the neural network involved in spatial movement and could be used to aid decisions about treatment.

Objective To examine the impact of spatial neglect on rehabilitation outcome, risk of falls, and discharge disposition in stroke survivors. Design Inception cohort. Setting Inpatient rehabilitation facility (IRF). Participants Individuals with unilateral brain damage after their first stroke (N=108) were assessed at IRF admission and discharge. At admission, 74 of them (68.5%) demonstrated symptoms of spatial neglect as measured using the Kessler Foundation Neglect Assessment Process (KF-NAP). Interventions Usual and standard IRF care. Main Outcome Measures The FIM, Conley Scale, number of falls, length of stay (LOS), and discharge disposition. Results The greater the severity of spatial neglect (higher KF-NAP scores) at IRF admission and the lower the FIM scores at admission as well as at discharge. Higher KF-NAP scores also correlated with greater LOS and lower FIM improvement rate. The presence of spatial neglect (KF-NAP score>0), but not Conley Scale scores, predicted falls such that participants with spatial neglect fell 6.5 times more often than those without symptoms. More severe neglect, indicated by KF-NAP scores at IRF admission, reduced the likelihood of returning home at discharge. A model that took spatial neglect and other demographic, socioeconomic, and clinical factors into account predicted home discharge. Rapid FIM improvement during IRF stay and lower annual income level were significant predictors of home discharge. Conclusions Spatial neglect after a stroke is a prevalent problem and may negatively affect rehabilitation outcome, risk of falls, and LOS.

Objective: To evaluate the evidence basis of single-domain cognitive tests frequently used by behavioral neurologists in an effort to improve the quality of clinical cognitive assessment. Methods: Behavioral Neurology Section members of the American Academy of Neurology were surveyed about how they conduct clinical cognitive testing, with a particular focus on the Neurobehavioral Status Exam (NBSE). In contrast to general screening cognitive tests, an NBSE consists of tests of individual cognitive domains (e.g., memory or language) that provide a more comprehensive diagnostic assessment. Workgroups for each of 5 cognitive domains (attention, executive function, memory, language, and spatial cognition) conducted evidence-based reviews of frequently used tests. Reviews focused on suitability for office-based clinical practice, including test administration time, accessibility of normative data, disease populations studied, and availability in the public domain. Results: Demographic and clinical practice data were obtained from 200 respondents who reported using a wide range of cognitive tests. Based on survey data and ancillary information, between 5 and 15 tests in each cognitive domain were reviewed. Within each domain, several tests are highlighted as being well-suited for an NBSE. Conclusions: We identified frequently used single-domain cognitive tests that are suitable for an NBSE to help make informed choices about clinical cognitive assessment. Some frequently used tests have limited normative data or have not been well-studied in common neurologic disorders. Utilizing standardized cognitive tests, particularly those with normative data based on the individual9s age and educational level, can enhance the rigor and utility of clinical cognitive assessment.

Given the increasing rates of stroke and our aging population, it is critical that we continue to foster innovation in stroke rehabilitation. Although there is evidence supporting cognitive rehabilitation in stroke, the set of cognitive domains effectively addressed to date represents only a small subset of the problems experienced by stroke survivors. Further, a gap remains between investigational treatments and our evolving theories of brain function. These limitations present opportunities for improving the functional impact of stroke rehabilitation. The authors use a case example to encourage the reader to consider the evidence base for cognitive rehabilitation in stroke, focusing on four domains critical to daily life function: (1) speech and language, (2) functional memory, (3) executive function and skilled learned purposive movements, and (4) spatial-motor systems. Ultimately, they attempt to draw neuroscience and practice closer together by using translational reasoning to suggest possible new avenues for treating these disorders.

Introduction: Delirium, a disorder of attention and arousal, poses a large public health burden. Inattention and fluctuating cognitive status, two primary delirium symptoms, also occur when specialized right brain systems are impaired. Although right hemisphere stroke may predispose to delirium, systematic assessment methods and management of these patients are not yet available. We sought to characterize the incidence of delirium in right hemisphere stroke patients and explore whether stroke localization was associated with delirium. Methods: We identified consecutive patients admitted to our stroke service with acute right hemisphere stroke over a 6-month period from our prospective stroke registry. We reviewed the medical record for core delirium symptoms: inattention, cognitive fluctuation, and either disorganized thinking, or altered level of consciousness. Delirium was assessed by systematically screening for trigger words. We compared baseline characteristics with Fisher’s exact and t-tests and assessed relation of stroke localization to delirium with logistic regression. Results: Of 105 patients with acute right hemisphere stroke, 27 (26%) had delirium. Delirium patients were older (mean age 78 vs. 68, p Conclusion: The high delirium incidence we found supports routine delirium screening in acute stroke patients. Stroke localization may be one factor to incorporate into screening tools. Studies to prospectively identify and treat delirium in both right and left hemisphere stroke patients are warranted.

Delirium is an acute attention and cognitive dysfunction, adversely affecting functional outcomes and mortality. As many as half of hospitalized right brain stroke survivors may develop delirium. Further, about 50% of right stroke patients experience spatial neglect, impairing safety and recovery. In this review we explore the brain mechanisms, which may explain the high incidence of delirium and spatial neglect after right-brain stroke. We suggest that brain networks for spatial attention and arousal, composed of ascending projections from the midbrain nuclei and integrating dorsal and ventral cortical and limbic components, may underlie impairments in delirium and spatial neglect. We propose that lateralized deficits in spatial neglect may arise because cortical and limbic components of these functional networks are disproportionally impaired by right-brain strokes, and that spatial neglect may lower the threshold for developing delirium. An improved understanding of the brain basis of delirium and spatial neglect could provide a critical biomarker for initiating preventive care in stroke patients at high risk of hospital morbidity and loss of independence.

Aphasia, a cognitive-linguistic disorder secondary to stroke, is a frequent and often chronic consequence of stroke with detrimental effects on autonomy and health-related quality of life. Treatment of aphasia can be approached in a number of ways. Impairment-based approaches that focus on training a specific linguistic form can be implemented. Additionally, functionally oriented intervention such as supported conversation and aphasia groups are also frequently utilized when providing a treatment program for an individual with aphasia. Creating a treatment approach that includes both impairment and functional methodologies and considers how these relate to the three domains proposed by the International Classification of Functioning Disability and Health (ICF)-body functions and structure, activity, and participation-can provide an individual with aphasia an optimal treatment program that is person-centered and multi-faceted.

To test the hypothesis that a left-dominant brain immune network (LD-BIN) might affect the occurrence of infection during inpatient rehabilitation of stroke and traumatic brain injury (TBI).A retrospective analysis was performed on electronic medical records between January 2009 and December 2010. All patients with left- or right-sided stroke or TBI were included into the study. The LD-BIN hypothesis was tested by comparing HAI rates depending on whether patients had left- or right-sided brain lesions.A large inpatient rehabilitation hospital.Among the patients (N=2236) with stroke or TBI who had either a left- or right-sided brain lesion, 163 patients were identified with HAIs.Not applicable.Frequency of HAIs.In the 163 patients identified with HAIs with a diagnosis of stroke or TBI, chi-square analysis revealed a significantly higher proportion of HAIs among patients with left-sided (n=98; 60.1%) relative to right-sided (n=65; 39.9%) brain injuries (χ(2)=6.68, P.01). These effects could not be attributed to either clinical or demographic factors.Our findings are consistent with the hypothesis that an LD-BIN may mediate vulnerability to infection during rehabilitation of patients with stroke or TBI. Further translational research investigating novel means of managing patients based on brain lesion location, and modulating the LD-BIN via behavioral and physiologic interventions, may result in neuroscience-based methods to improve infection resistance in brain-injured patients.

This study assessed the prevalence of convergence insufficiency (CI) with and without simultaneous vision dysfunctions within the traumatic brain injury (TBI) sample population because although CI is commonly reported with TBI, the prevalence of concurrent visual dysfunctions with CI in TBI is unknown.A retrospective analysis of 557 medical records from TBI civilian patients was conducted. Patients were all evaluated by a single optometrist. Visual acuity, oculomotor function, binocular vision function, accommodation, visual fields, ocular health, and vestibular function were assessed. Statistical comparisons between the CI and non-CI, as well as inpatient and outpatient subgroups, were conducted using χ and Z tests.Approximately 9% of the TBI sample had CI without the following simultaneous diagnoses: saccade or pursuit dysfunction; third, fourth, or sixth cranial nerve palsy; visual field deficit; visual spatial inattention/neglect; vestibular dysfunction; or nystagmus. Photophobia with CI was observed in 16.3% (21 of 130), and vestibular dysfunction with CI was observed in 18.5% (24 of 130) of the CI subgroup. Convergence insufficiency and cranial nerve palsies were common and yielded prevalence rates of 23.3% (130 of 557) and 26.9% (150 of 557), respectively, within the TBI sample. Accommodative dysfunction was common within the nonpresbyopic TBI sample, with a prevalence of 24.4% (76 of 314). Visual field deficits or unilateral visual spatial inattention/neglect was observed within 29.6% (80 of 270) of the TBI inpatient subgroup and was significantly more prevalent compared with that of the outpatient subgroup (p0.001). Most TBI patients had visual acuities of 20/60 or better in the TBI sample (85%; 473 of 557).Convergence insufficiency without simultaneous visual or vestibular dysfunctions was observed in about 9% of the visually symptomatic TBI civilian population studied. A thorough visual and vestibular examination is recommended for all TBI patients.

The experience of having a stroke involves changes to many activities in social, leisure and work life, and the way we interact with the world. The purpose of this chapter is to describe the changes in mind-body interactionthat affect people who have experienced a stroke. We will explain health strategies important after stroke, and describe specific mind-body problems that affect daily life: issues with movement and mobility, problems perceiving and moving in the 3-D world, problems with sensation, self-awareness, and pain. We also discuss mind-body problems with mood and emotion, social function, concentration and memory problems, and communication disorder (aphasia) and fatigue. We end the chapter describing important steps in returning to the community for stroke survivors and their families, and cultural issues.

Visual impairments are common after traumatic brain injury (TBI) and negatively affect quality of life. We describe a 39-year-old woman with a severe TBI who was evaluated by the inpatient optometry and vision rehabilitation service with findings of complete right homonymous hemianopia and right cranial nerve III palsy with 30-degree right exotropia (eye turn out) and complete right ptosis (eyelid will not open). The 30-degree exotropia advantageously generated 30 degrees of right visual field expansion when the right ptosis was treated with a magnetic levator prosthesis, which restores eyelid opening. Once opened, the patient used visual field expansion derived from a right exotropia to overcome functional impairments caused by right hemianopia. Field expansion improved the patient's wheelchair mobility and reaching tasks during inpatient therapy. This is the first report of visual field expansion by strabismus facilitated by correction of ptosis. Strabismus should be considered for its potential field expansion benefits when homonymous visual deficits are present, before considering patching. A multidisciplinary vision rehabilitation team is well suited to make this determination.

Stroke is a chronic disease. Standardized assessment is essential in order to determine areas for treatment. Individuals with aphasia are often excluded from research, because it is believed that their language impairments may impact their ability to provide informed consent. Thus, right spatial neglect could be under-diagnosed.This study was developed to (1) determine the frequency of spatial neglect in chronic left-brain stroke survivors with aphasia, (2) determine the clinical utility of an aphasia-friendly consent form, and (3) determine any differences between neglect and no-neglect groups regarding activities of daily living (ADL) performance and community independence.Forty-six people were consented at community center. Three were screen failures secondary to the exclusion criteria. A novel, aphasia-friendly consent form was developed to facilitate participation of individuals with aphasia. This enabled 93% or 40 out of the 43 recruited participants to be included in this study. The Behavioral Inattention Test-conventional and the Catherine Bergego Scale via Kessler Foundation Neglect Assessment Process (CBS via KF-NAP) were utilized to determine neglect. The Life Space Questionnaire was used to determine community mobility and independence. The Barthel Index (BI) was used for objective clarification of performance in ADL.Successful use of the consent form resulted in determination that five out of 40 (12.5%) met criteria for spatial neglect; (on the CBS via KF-NAP). The neglect group had lower scores on the Life Space, suggesting less community mobility and independence, however, it was not statistically significant (p = 0.16). Differences in BI scores were also not significant (p = .013) but the neglect group did have reduced independence.This study demonstrates the need to administer functional neglect assessments in left-brain stroke and to include individuals with aphasia in research.

Whyte J, Barrett AM. Advancing the evidence base of rehabilitation treatments: a developmental approach. Translational research refers to the development of new scientific discoveries into evidence-based treatments for human diseases and conditions. This developmental process requires that a number of scientific, as well as social and psychological obstacles, be overcome during a sequence of research stages that address different goals. Rehabilitation, like other biomedical disciplines, requires this kind of developmental process. For a variety of reasons, however, development of rehabilitation treatments is less linear than the familiar phases of pharmaceutical research. In addition, research on treatments intended to address impairments (body structure/function, in terms of the International Classification of Functioning, Disability and Health ), faces the challenge of determining the likely impact of an impairment-level treatment on the multifaceted activities and aspects of participation that are the typical goals of rehabilitation treatments. This article describes the application of treatment theory and enablement theory to the development of new impairment-based treatments, and examines similarities and differences between the developmental sequence needed for rehabilitation treatment research versus pharmaceutical research in other areas of medicine.

Background Spatial bias in natural, implicit tasks such as reaching and grasping may manifest differently from that in arbitrary laboratory-experiment line bisection tasks. Because spatial processing in everyday activities is difficult to quantify, it is important to study spatial behavior in an implicit laboratory task. Drawing tasks of copying lines or objects integrate spatial perceptual-attentional ("where") input and motor-intentional ("aiming") output, and may be more implicit than line bisection because participants are unaware that the placement of their drawings will be assessed. Objectives We examined whether it is possible to distinguish "where" and "aiming" spatial biases in a line-copying task. We examined changes in "where" and "aiming" biases in response to bottom-up versus top-down cues (hemispace presentation and drawing direction). Methods In 13 healthy adults, we collected copied-line displacements and lengths in both the natural (left-right congruency) and reversed (left-right incongruency) viewing conditions, to distinguish "where" and "aiming" biases. Results Participants displaced lines leftward (P=0.01) as they copied, displaying primarily a "where" bias. They displaced lines in the drawing direction irrespective of viewing condition, a finding consistent with induced "aiming" effects (P=0.291). Presenting lines on participants' right or left side did not affect the "where" spatial bias. Cues did not affect copied-line lengths. Conclusions We showed that an implicit laboratory-experiment task of copying lines can discern complex stages of spatial processing in healthy adults. Further evaluation of this task will greatly contribute to the understanding of mechanisms of human spatial cognition.

Background/Aims: Healthy individuals demonstrate leftward bias on visuospatial tasks such as line bisection, which has been attributed to right brain dominance. We investigated whether this asymmetry occurred in patients with probable dementia of the Alzheimer type (pAD) which is associated with neurodegenerative changes affecting temporoparietal regions. Methods: Subjects with pAD and matched controls performed a line bisection task in near and far space under conditions of no distraction, left-sided visual distraction and right-sided visual distraction. Results: Participants with pAD manifested different motor-preparatory ‘aiming’ spatial bias than matched controls. There were significantly greater rightward ‘aiming’ motor-intentional errors both without distraction and with right-sided distraction. Conclusion: ‘Aiming’ motor-preparatory brain activity may be induced by distraction in pAD subjects as compared to typical visual-motor function in controls.

Aphasia researchers and clinicians share some basic beliefs about language recovery post stroke. Most agree there is a spontaneous recovery period and language recovery may be enhanced by participation in a behavioral therapy program. The application of biological interventions in the form of pharmaceutical treatments or brain stimulation is less well understood in the community of people who work with individuals having aphasia. The purpose of this article is to review the literature on electrical brain stimulation as an intervention to improve aphasia recovery. The article will emphasize emerging research on the use of transcranial magnetic stimulation (TMS) to accelerate stroke recovery. We will profile the current US Food and Drug Administration (FDA)-approved application to depression to introduce its potential for future application to other syndromes such as aphasia.

Patterns of cerebral asymmetry related to visuospatial functions may change with age. The typical leftward bias on a line bisection task may reflect cerebral asymmetry. With age, such leftward bias decreases. This study demonstrated that the age-related decrease of leftward bias may actually be sex-specific. In addition, previous research suggests that young adults’ deviation in line bisection may reflect asymmetric hemispheric activation of perceptual–attentional “where” spatial systems, rather than motor-intentional “aiming” spatial systems; thus, we specifically fractionated “where” and “aiming” bias of men and women ranging in age from 22 to 93 years old. We observed that older men produced greater rightward line bisection errors, of primarily “where” spatial character. However, women's errors remained leftward biased, and did not significantly change with age. “Where” spatial systems may be linked to cortico-cortical processing networks involving the posterior part of the dorsal visuospatial processing stream. Thus, the current results are consistent with the conclusion that reduced right dorsal spatial activity in aging may occur in the male, but not female, adult spatial system development. (JINS, 2011, 17, 455–462)

Proposals that adaptation with left-shifting prisms induces neglect-like symptoms in normal individuals rely on a dissociation between the postadaptation performance of individuals trained with left- versus right-shifting prisms (e.g., Colent, Pisella, & Rossetti, 2000). A potential problem with this evidence is that normal young adults have an a priori leftward bias (e.g., Jewell & McCourt, 2000). In Experiment 1, we compared the line bisection performance of young adults to that of aged adults, who as a group may lack a leftward bias in line bisection. Participants trained with both left- and right-shifting prisms. Consistent with our hypothesis, while young adults demonstrated aftereffects for left, but not right prisms, aged adults demonstrated reliable aftereffects for both prisms. In Experiment 2, we recruited a larger sample of young adults, some of whom were right-biased at baseline. We observed an interaction between baseline bias and prism-shift, consistent with the results of Experiment 1: Left-biased individuals showed a reduced aftereffect when training with right-shifting prisms and right-biased individuals showed a reduced aftereffect when training with left-shifting prisms. These results suggest that previous failures to find generalizable aftereffects with right-shifting prisms may be driven by participants’ baseline biases rather than specific effects of the prism itself. (JINS, 2010, 16, 795–804.)

Monocular patching might improve perceptual-attentional, not motor-intentional deficits in a patient with chronic post-stroke left spatial neglect. Performing a line-cancellation task, his omission errors were associated with a perceptual-attentional 'where' deficit, while perseverative errors were associated with 'aiming' motor-intentional bias. Contralesional patching had no effect on the omissions (p = .871), whereas ipsilesional patching reduced left-sided omissions compared with the unpatched condition (p = .016). Neither patching condition altered perseverative errors. Further research is needed to examine whether targeting treatments to spatial neglect symptoms (omissions, perseveration) results in improved outcomes.

Hemispatial neglect (HSN) is a frequent, conspicuous neurobehavioral accompaniment of brain injury. Patients with HSN share several superficial similarities, leading earlier clinical neuroscientists to view neglect as a unitary condition associated with brain structures that mediate relatively discrete spatial cognitive mechanisms. Over the last two decades, research largely deconstructed the neglect syndrome, revealing a remarkable heterogeneity of behaviors and providing insight into multiple component processes, both spatial and nonspatial, that contribute to hemispatial neglect. This review surveys visual HSN, presenting first the means for detection and diagnosis in its manifold variations. We summarize cognitive operations relevant to spatial attention and evidence for their role in neglect behaviors and then briefly consider neural systems that may subserve the component processes. Finally, we propose several methods for rehabilitating HSN, including the challenges facing remediation of such a heterogeneous cognitive disorder.