Post-stroke Unilateral Spatial Neglect Research Articles

Current knowledge and practice of post-stroke unilateral spatial neglect rehabilitation: a national survey of Nigerian physiotherapists

BackgroundUnilateral spatial neglect (USN) is a leading cause of disability and handicap in stroke survivors affecting functional recovery. Therapists’ knowledge and practice in post-stroke unilateral spatial neglect are key to the success of rehabilitation.AimThis study aimed to evaluate physiotherapists’ knowledge of USN and the current practice of USN management.MethodA cross-sectional study was undertaken among Nigerian physiotherapists (N = 240). An online structured questionnaire that assessed respondents’ knowledge, current practice, barriers, and enablers to post-stroke USN rehabilitation was administered.ResultsThe total knowledge score was 12.6 ± 4.75 on a scale of 25. Few physiotherapists (7.92%) demonstrated good knowledge of USN. Postgraduate certification (p = 0.001), clinical practice setting (p = 0.008), and working full time in neurorehabilitation (p = 0.033) were significantly associated with the therapist’s knowledge of USN. There was a nonsignificant positive correlation between the duration of practice in the neurorehabilitation setting (r = 0.02; p = 0.854) and USN knowledge. A nonsignificant minimal negative correlation between practice as a physiotherapist (r = − 0.02; p = 0.772) and USN knowledge was also noted. The age of physiotherapists showed no linear relationship with the therapist’s knowledge of USN (r = − 0.00; p = 0.992). Constraint-induced movement therapy (86.47%) was the most commonly used USN treatment, while Albert’s test (49.37%) was the most utilized screening tool for USN.ConclusionsVery few physiotherapists had good knowledge of USN. Participants’ knowledge increased as they attained higher education levels relating to neurological physiotherapy. These findings emphasize the need for specialist rehabilitation training for physiotherapy practice.

Effectiveness of repetitive transcranial magnetic stimulation on post-stroke unilateral spatial neglect

Post-stroke cognitive impairment refers to the cognitive impairment caused by stroke. Unilateral spatial neglect is the main symptom and results in remarkably lower independence in activities of daily living and participation. Recent studies suggested that repetitive transcranial magnetic stimulation (rTMS) may have a positive effect on post-stroke cognitive impairment, but no relevant systematic review has been conducted on post-stroke cognitive impairment, especially unilateral spatial neglect. Therefore, relevant studies on rTMS in the treatment of post-stroke were collected and analyzed by systematic review and meta-analysis to determine whether rTMS can improve the cognitive function of patients, especially post-stroke unilateral spatial neglect, to provide reliable evidence for rTMS intervention. PubMed, Cochrane Central Register of Controlled Trials, Embase, PsycINFO databases, Web of Science and CINAHL were searched up to February 3, 2021. Three authors screened the reviews and independently assessed their methodological quality using the Jadad scale. The number of studies finally pooled was 28, and the sample size was 819. In the overall cognition function, the efficacy of the intervention group was superior to that of the control group. This meta-analysis result indicated that rTMS influences unilateral spatial neglect. rTMS was effective in improving patients’ activities of daily living. Subgroup analysis showed the preferred items in selecting frequency pulses and session. Furthermore, rTMS could not improve unilateral spatial neglect with an onset time of less than 1 month and over 1 month. This meta-analysis shows that rTMS intervention may be a promising way to treat post-stroke cognitive impairment.

Current knowledge and practice of post-stroke unilateral spatial neglect rehabilitation: A cross-sectional survey of South African neurorehabilitation physiotherapists.

BackgroundUnilateral spatial neglect (USN) affects the rehabilitation process leading to poor functional outcomes after stroke. South African physiotherapists’ level of uptake of available evidence in USN rehabilitation and the barriers they encounter are not known.ObjectivesTo evaluate knowledge, current practice enablers and barriers to USN management in stroke survivors amongst physiotherapists in South Africa.MethodsOur cross-sectional survey used a total sampling technique. Questionnaires were sent to neurorehabilitation physiotherapists in South Africa. Descriptive and inferential statistics analysed the data.ResultsThe overall knowledge score of USN was 14.11 ± 5.23 of a total of 25. The knowledge was good for definitions of USN; moderate for incidences, causes, screening, diagnosis and prognosis of USN and poor for pharmacological approaches to the management of USN. A significant low positive correlation between respondents’ age (r = 0.46; p = 0.016) and years of practice as a physiotherapist (r = 0.43; p = 0.026) and knowledge of USN was found. The most frequently utilised intervention was constraint-induced movement therapy; the commonly utilised assessment tool was the comb and razor test. ‘Inadequate therapy time’ (55.56%) and ‘lack of relevant equipment for rehabilitation of USN’ (38.89%) were identified as major barriers to USN rehabilitation. Major enablers to USN rehabilitation were the ‘presence of multidisciplinary stroke team in clinical practice’ (83.35%) and ‘availability of adequate staff’ (76.47%).ConclusionPhysiotherapists demonstrated a fair knowledge of USN although knowledge about pharmacological management of USN was modest. Current practice in post-stroke USN by South African neuro-physiotherapists follows current evidence and practice guidelines.Clinical implicationOur study shows the level of knowledge and current practice of post-stroke USN rehabilitation. The demonstrated fair knowledge of USN may be improved through training, curriculum modifications or continuing professional development. Identified barriers to the rehabilitation of post-stroke USN can assist health policy, managers and clinicians to improve stroke-specific care.

Effect of Eye Movement Training on Balance in Post Stroke Patients with Unilateral Spatial Neglect. First Preliminary report

Background: Unilateral Spatial Neglect (USN) is a complex disorder associated with stroke and is more severe and persistent following right hemisphere damage. Stroke patients have mobility limitations, muscle weakness, and behaviors disorders. The problem with USN is lack of orientation and information from affected side that may cause balance problems specially in elderly survivors. Training eye movements are aimed at improving visual function by training patients to navigate the blind hemifield and increase their overall sensitivity. Accurate reliable knowledge of balance in stroke survivors is important for prognosis and to predict falls. Aim of the study: This study was designed to find out the effect of training eye movements on balance in elderly post stroke survivors with USN. Subjects and Methods: The study included 15 of both sexes with post stroke USN (11 males and 4 females) their mean age was 69.1 ± 1.9 years. Patients received sequentially in same session training for eye movement program and a traditional gait training program 4 days/week for 6 weeks. Balance assessment was measured by Berg Balance Scale (BBS), Time Up and go test (TUG), 10 meters Talking Test (10mWT), and 6 Minutes Walking Test (6MWT). Results: there were significant changes in between pre and post-study as the analysis of mean values of BBS, TUG, 10mW, and 6MWT.Conclusion: eye movement training had a significant effect on improving balance in post stroke survivors with USN. Eye movement training improved patients with USN ability to explorer the blind hemispace and to improve balance.

The effect of theta-burst stimulation on unilateral spatial neglect following stroke: a systematic review

Objective: To evaluate the effectiveness of theta-burst stimulation for the treatment of stroke-induced unilateral spatial neglect. Data sources: A systematic literature search was conducted from the inception of each database to 30 June 2018 using CINAHL, EMBASE, PubMed, PsycINFO, and Scopus. Review methods: Articles were included if theta-burst stimulation was used to treat neglect following a stroke. The additional a priori inclusion criteria were as follows: (1) ⩾3 adult (⩾18 years) participants, (2) ⩾50% stroke population, and (3) peer-reviewed journal articles published in English. Extracted data included study and treatment characteristics, results, and adverse events. Results: Nine studies met the inclusion criteria, generating a total of 148 participants. Eight studies evaluated a continuous stimulation protocol and one study investigated an intermittent stimulation protocol. Overall, both protocols significantly improved neglect severity when compared against placebo or active controls (P < 0.05). Adding smooth pursuit training to theta-burst stimulation did not improve neglect relative to when the stimulation was delivered alone (P > 0.05). There was inconsistent reporting of neglect terminology, outcome measures, and adverse events. The treatment characteristics were heterogeneous among the trials. Conclusion: This systematic review found that theta-burst stimulation seems to improve post-stroke unilateral spatial neglect, but because the evidence is limited to a few small studies with varied and inconsistent protocols and use of terminology, no firm conclusion on effectiveness can be drawn.

Post-stroke visual neglect affects goal-directed locomotion in different perceptuo-cognitive conditions and on a wide visual spectrum.

Unilateral spatial neglect (USN), a highly prevalent and disabling post-stroke deficit, has been shown to affect the recovery of locomotion. However, our current understanding of USN role in goal-directed locomotion control, and this, in different cognitive/perceptual conditions tapping into daily life demands, is limited. To examine goal-directed locomotion abilities in individuals with and without post-stroke USN vs. healthy controls. Participants (n = 45, n = 15 per group) performed goal-directed locomotion trials to actual, remembered and shifting targets located 7 m away at 0° and 15° right/left while immersed in a 3-D virtual environment. Greater end-point mediolateral displacement and heading errors (end-point accuracy measures) were found for the actual and the remembered left and right targets among those with post-stroke USN compared to the two other groups (p < 0.05). A delayed onset of reorientation to the left and right shifting targets was also observed in USN+ participants vs. the other two groups (p < 0.05). Results on clinical near space USN assessment and walking speed explained only a third of the variance in goal-directed walking performance. Post-stroke USN was found to affect goal-directed locomotion in different perceptuo-cognitive conditions, both to contralesional and ipsilesional targets, demonstrating the presence of lateralized and non-lateralized deficits. Beyond neglect severity and walking capacity, other factors related to attention, executive functioning and higher-order visual perceptual abilities (e.g. optic flow perception) may account for the goal-directed walking deficits observed in post-stroke USN+. Goal-directed locomotion can be explored in the design of future VR-based evaluation and training tools for USN to improve the currently used conventional methods.

Post-stroke unilateral spatial neglect: virtual reality-based navigation and detection tasks reveal lateralized and non-lateralized deficits in tasks of varying perceptual and cognitive demands

BackgroundUnilateral spatial neglect (USN), a highly prevalent and disabling post-stroke impairment, has been shown to affect the recovery of locomotor and navigation skills needed for community mobility. We recently found that USN alters goal-directed locomotion in conditions of different cognitive/perceptual demands. However, sensorimotor post-stroke dysfunction (e.g. decreased walking speed) could have influenced the results.Analogous to a previously used goal-directed locomotor paradigm, a seated, joystick-driven navigation experiment, minimizing locomotor demands, was employed in individuals with and without post-stroke USN (USN+ and USN-, respectively) and healthy controls (HC).MethodsParticipants (n = 15 per group) performed a seated, joystick-driven navigation and detection time task to targets 7 m away at 0°, ±15°/30° in actual (visually-guided), remembered (memory-guided) and shifting (visually-guided with representational updating component) conditions while immersed in a 3D virtual reality environment.ResultsGreater end-point mediolateral errors to left-sided targets (remembered and shifting conditions) and overall lengthier onsets in reorientation strategy (shifting condition) were found for USN+ vs. USN- and vs. HC (p < 0.05). USN+ individuals mostly overshot left targets (− 15°/− 30°). Greater delays in detection time for target locations across the visual spectrum (left, middle and right) were found in USN+ vs. USN- and HC groups (p < 0.05).ConclusionUSN-related attentional-perceptual deficits alter navigation abilities in memory-guided and shifting conditions, independently of post-stroke locomotor deficits. Lateralized and non-lateralized deficits in object detection are found. The employed paradigm could be considered in the design and development of sensitive and functional assessment methods for neglect; thereby addressing the drawbacks of currently used traditional paper-and-pencil tools.

Visual perceptual deficits and their contribution to walking dysfunction in individuals with post-stroke visual neglect

ABSTRACTBackground: Unilateral spatial neglect (USN), a highly prevalent and disabling post-stroke deficit, severely affects functional mobility. Visual perceptual abilities (VPAs) are essential in activities involving mobility. However, whether and to what extent post-stroke USN affects VPAs and how they contribute to mobility impairments remains unclear. Objectives: To estimate the extent to which VPAs in left and right visual hemispaces are (1) affected in post-stroke USN; and (2) contribute to goal-directed locomotion. Methods: Individuals with (USN+, n = 15) and without (USN-, n = 15) post-stroke USN and healthy controls (HC, n = 15) completed (1) psychophysical evaluation of contrast sensitivity, optic flow direction and coherence, and shape discrimination; and (2) goal-directed locomotion tasks. Results: Higher discrimination thresholds were found for all VPAs in the USN+ group compared to USN- and HC groups (p < 0.05). Psychophysical tests showed high sensitivity in detecting deficits in individuals with a history of USN or with no USN on traditional assessments, and were found to be significantly correlated with goal-directed locomotor impairments. Conclusion: Deficits in VPAs may account for the functional difficulties experienced by individuals with post-stroke USN. Psychophysical tests used in the present study offer important advantages and can be implemented to enhance USN diagnostics and rehabilitation.

Ecological Virtual Reality Evaluation of Neglect Symptoms (EVENS): Effects of Virtual Scene Complexity in the Assessment of Poststroke Unilateral Spatial Neglect

Background. Unilateral spatial neglect (USN) is a highly prevalent and disabling poststroke impairment. USN is traditionally assessed with paper-and-pencil tests that lack ecological validity, generalization to real-life situations and are easily compensated for in chronic stages. Virtual reality (VR) can, however, counteract these limitations. Objective. We aimed to examine the feasibility of a novel assessment of USN symptoms in a functional shopping activity, the Ecological VR-based Evaluation of Neglect Symptoms (EVENS). Methods. EVENS is immersive and consists of simple and complex 3-dimensional scenes depicting grocery shopping shelves, where joystick-based object detection and navigation tasks are performed while seated. Effects of virtual scene complexity on navigational and detection abilities in patients with (USN+, n = 12) and without (USN−, n = 15) USN following a right hemisphere stroke and in age-matched healthy controls (HC, n = 9) were determined. Results. Longer detection times, larger mediolateral deviations from ideal paths and longer navigation times were found in USN+ versus USN− and HC groups, particularly in the complex scene. EVENS detected lateralized and nonlateralized USN-related deficits, performance alterations that were dependent or independent of USN severity, and performance alterations in 3 USN− subjects versus HC. Conclusion. EVENS’ environmental changing complexity, along with the functional tasks of far space detection and navigation can potentially be clinically relevant and warrant further empirical investigation. Findings are discussed in terms of attentional models, lateralized versus nonlateralized deficits in USN, and tasks-specific mechanisms.

Exploring barriers and facilitators to the clinical use of virtual reality for post-stroke unilateral spatial neglect assessment

Background: Hemineglect, defined as a failure to attend to the contralesional side of space, is a prevalent and disabling post-stroke deficit. Conventional hemineglect assessments lack sensitivity as they contain mainly non-functional tasks performed in near-extrapersonal space, using static, two-dimensional methods. This is of concern given that hemineglect is a strong predictor for functional deterioration, limited post-stroke recovery, and difficulty in community reintegration. With the emerging field of virtual reality, several virtual tools have been proposed and have reported better sensitivity in neglect-related deficits detection than conventional methods. However, these and future virtual reality-based tools are yet to be implemented in clinical practice.Objectives: The present study aimed to explore the barriers/facilitators perceived by clinicians in the use of virtual reality for hemineglect assessment; and to identify features of an optimal virtual assessment.Methods: A qualitative descriptive process, in the form of focus groups, self-administered questionnaire and individual interviews was used.Results: Two focus groups (n = 11 clinicians) were conducted and experts in the field (n = 3) were individually interviewed. Several barriers and facilitators, including personal, institutional, client suitability, and equipment factors, were identified. Clinicians and experts in the field reported numerous features for the virtual tool optimization.Conclusion: Factors identified through this study lay the foundation for the development of a knowledge translation initiative towards an implementation of a virtual assessment for hemineglect. Addressing the identified barriers/facilitators during implementation and incorporating the optimal features in the design of the virtual assessment could assist and promote its eventual adoption in clinical settings.Implications for rehabilitationA multimodal and active knowledge translation intervention built on the presently identified modifiable factors is suggested to be implemented to support the clinical integration of a virtual reality-based assessment for post-stroke hemineglect.To amplify application and usefulness of a virtual-reality based tool in the assessment of post-stroke hemineglect, optimal features identified in the present study should be incorporated in the design of such technology.

Post-stroke unilateral spatial neglect treated with acupuncture and rehabilitation: a randomized controlled trial

To observe the impacts on post-stroke unilateral spatial neglect treated with acupuncture for "regaining consciousness, benefiting marrow and opening orifices" and rehabilitation. Forty patients of post-stroke unilateral spatial neglect were randomized into an observation group and a control group, 20 cases in each one. In the observation group, acupuncture was applied to the acupoints for "regaining consciousness, benefiting marrow and opening orifices", named Baihui (GV 20), Sishencong (EX-HN 1), Benshen (GB 13), Shenting (GV 24), and the bilateral yuan-primary points and luo-connecting points of the heart meridian, pericardium meridian and kidney meridian, as well as the acupoints along the affected meridians. Additionally, the rehabilitation was provided. In the control group, acupuncture at the acupoints along the affected meridians and rehabilitation were adopted. The treatment was given once a day, 5 times a week. After 8 weeks of treatment the evaluation was made. the indexes of unilateral spatial neglect such as line bisection test, the score of the mini-mental state examination (MMSE), the score of simple Fugl-Meyer motor function assessment and the modified Barthel indexes were adopted for the assessment of the severity of unilateral spatial neglect, cognitive function, motor function, and the activities of daily living. After treatment, the indexes of unilateral spatial neglect (line bisection test, line cancellation test, clock-drawing test and copying drawing test), MMSE score, the simple Fugl-Meyer motor function assessment and modified Barthel indexes were all improved as compared with those before treatment in the two groups (all P<0.01). The improvements in the observation group were more obvious than those in the control group (P<0.05, P<0.01). The combination of acupuncture treatment for "regaining consciousness, benefiting marrow and opening orifices" and rehabilitation much more effectively alleviates the severity of post-stroke unilateral spatial neglect and improves the motor function and the activities of daily living in the patients.

Repetitive Transcranial Magnetic Stimulation (rTMS) for Higher Brain Function Deficits

The management of higher brain dysfunctions such as stroke-induced unilateral spatial neglect (USN) or aphasia is crucial because these dysfunctions have devastating neurological repercussions on the patients' daily life and quality of life. Impairment of the physiological interhemispheric rivalry is often the result of brain insults such as strokes or traumatic injuries, and it may lead to USN or aphasia. Repetitive transcranial magnetic stimulation (rTMS), a non-invasive brain stimulation method, is a promising tool for restoring the pathological imbalance in interhemispheric rivalry by either suppressing the hyperactivity of the unaffected hemisphere or facilitating hypoactivity in the affected hemisphere. The concept of paradoxical functional facilitation (Kapur, 1996) has important clinical implications when coupled with rTMS applications. In addition to conventional rTMS (c-rTMS), other clinically relevant protocols of patterned rTMS (p-rTMS) have been developed: the theta burst stimulation (TBS), the paired associative stimulation (PAS), and the quadripulse stimulation (QPS). TBS is commonly used in the rehabilitation of patients with post-stroke USN and those with non-fluent aphasia because of its prolonged beneficial effects and the short duration of stimulation. TBS may be considered an effective and safe protocol of rTMS. We foresee broader clinical applications of p-rTMS (TBS) and c-rTMS in the treatment of various neurological deficits.

Impact of post-stroke unilateral spatial neglect on goal-directed arm movements: systematic literature review

Background: Unilateral spatial neglect (USN), a highly prevalent post-stroke impairment, refers to one's inability to orient or respond to stimuli located in the contralesional visual hemispace. Unilateral spatial neglect has been shown to strongly affect motor performance in functional activities, including non-affected upper extremity (UE) movements. To date, our understanding of the effects of USN on goal-directed UE movements is limited and comparing performance of individuals post-stroke with and without USN is required.Objective: To determine, in individuals with stroke, how does the presence of USN, in comparison to the absence of USN, impacts different types of goal-directed movements of the non-affected UE.Methods: The present review approach consisted of a comprehensive literature search, an assessment of the quality of the selected studies and qualitative data analysis.Results: A total of 20 studies of moderate to high quality were selected. The USN-specific impairments were found in tasks that required a perceptual, memory-guided or delayed actions, and fewer impairments were found in tasks that required an immediate action to a predefined target.Conclusion: The results indicate that USN contributes to deficits observed in action execution with the non-effected UE that requires greater perceptual demands.

Determining the Barriers and Facilitators to Adopting Best Practices in the Management of Poststroke Unilateral Spatial Neglect: Results of a Qualitative Study

Background: A gap exists between best and actual management of poststroke unilateral spatial neglect (USN). Given the negative impact of USN on poststroke recovery, knowledge translation efforts are needed to optimize USN management. To date, no study has investigated the specific barriers and facilitators affecting USN management during the acute care process. Objective: To identify the facilitators and barriers that affect evidence-based practice use by occupational therapists (the primary discipline managing USN) when treating individuals with acute poststroke USN. Methods: Focus group methodology elicited information from 9 acute care occupational therapists. Results: Key barriers identified included lack of basic evidence-based practice skills specific to USN treatment and personal motivation to change current practices and engrained habits. Key facilitators included the presence of a multidisciplinary stroke team, recent graduation, and an environment with access to learning time and resources. Synthesized Web-based learning was also seen as important to uptake of best practices. Conclusion: It is estimated that upwards of 40% of patients experience poststroke USN in the acute phase, and we have evidence of poor early management. This study identified several modifiable factors that prepare the ground for the creation and testing of a multimodal knowledge translation intervention aimed at improving clinicians’ best practice management of poststroke USN.

Increasing knowledge of best practices for occupational therapists treating post-stroke unilateral spatial neglect: Results of a knowledge-translation intervention study

The aim of this study was to investigate: (i) the feasibility of delivering a multi-modal knowledge translation intervention specific to the management of acute post-stroke unilateral spatial neglect; and (ii) the impact of the knowledge translation intervention on occupational therapists' knowledge of evidence-based unilateral spatial neglect problem identification, assessment and treatment, and self-efficacy related to evidence-based practice implementation. A 3-period (pre-post) repeated measures design. Acute care occupational therapists treating patients with post-stroke unilateral spatial neglect were recruited from two major Canadian cities. Participants completed two pre-intervention assessments, took part in a day-long interactive multi-modal knowledge translation intervention and a subsequent 8-week follow-up, and completed a post-intervention assessment. Knowledge of evidence-based problem identification, assessment and treatment of unilateral spatial neglect, and self-efficacy to perform evidence-based practice activities were measured using standard scales. The intervention was tested on 20 occupational therapists. Results indicate a significant improvement in knowledge of best practice unilateral spatial neglect management (p < 0.000) and evidence-based practice self-efficacy in carrying out evidence-based practice activities (p < 0.045) post-intervention. Use of a multi-modal knowledge translation intervention is feasible and can significantly improve occupational therapists' knowledge of unilateral spatial neglect best practices and self-efficacy. The findings should help advance best practices specific to the management of post-stroke unilateral spatial neglect as well as informing knowledge translation studies in other areas of practice.

Brain Activity Stimulated by Prism Adaptation Tasks Utilized for the Treatment of Unilateral Spatial Neglect: A Study with fNIRS.

We investigated the neurological basis for efficacy of prism adaptation therapy, which is used for the treatment of poststroke unilateral spatial neglect (USN). Study subjects were 6 USN-positive (+), 6 USN-negative patients, and 6 healthy volunteer control subjects. USN was identified by the Behavioural Inattention Test (BIT). During the tasks, brain activity was assessed with fNIRS via changes in oxyHb concentration per unit length. There was no significant difference in the number of errors in the task between the 3 groups. However, in the USN(+) group there was a significantly greater reduction in oxyHb levels in the right parietal association cortex during the prism adaptation task than in the other 2 groups (P < 0.05). There was an immediate improvement in USN symptoms as well as a significant increase in oxyHb levels during the prism adaptation in the channels covering the right frontal and parietal lobes in 2 patients in the USN(+) group (P < 0.05). This result suggested that decreased activity in the right parietal association cortex, which is related to spatial perception, during the prism adaptation task and task-induced reorganization of the right frontal and parietal areas were involved in improvement in USN symptoms.

Superior Colliculi Involvement in Poststroke Unilateral Spatial Neglect: A Pilot Study

Purpose: The neural mechanisms underlying unilateral spatial neglect (USN) are unclear. The superior colliculi (SC) may be involved in USN expression, and the spatial summation effect (SSE), where reaction times to bilateral stimuli are faster than to unilateral, may be a behavioral index of SC function. We determined the feasibility of investigating SC contribution to poststroke USN using the SSE in 3 groups. Methods: Seven participants with left near-extrapersonal space USN (USN+) following right hemisphere stroke, 10 without (USN-), and 10 controls were tested under binocular/monocular (right eye patched) conditions while responding to unilateral/bilateral stimuli. Control and USN- groups completed the SSE paradigm. Results: Most USN+ participants were unable to initiate the SSE paradigm due to poor visual fixation and demonstrated higher contrast sensitivity for left-sided stimuli. Controls showed an SSE (under both viewing conditions) while the USN- showed an abnormal SSE whereby reaction times to bilateral stimuli were faster than to unilateral-left but not to unilateral-right stimuli (under both binocular/monocular conditions). Conclusion: This study is the first to investigate SC contribution in poststroke USN using the SSE; we identified higher contrast sensitivity to left-sided stimuli and poor fixation in the USN+ group. These findings suggest avenues for research that may lead to novel rehabilitation interventions.