Continuing issues in the assessment of neglect

The line bisection bias as a deficit of proportional reasoning - evidence from number line estimation in neglect

This study aimed to investigate whether neurological patients presenting with a bias in line bisection show specific problems in bisecting a line into two equal parts or their line bisection bias rather reflects a special case of a deficit in proportional reasoning more generally. In the latter case, the bias should also be observed for segmentations into thirds or quarters. To address this question, six neglect patients with a line bisection bias were administered additional tasks involving horizontal lines (e.g., segmentation into thirds and quarters, number line estimation, etc.). Their performance was compared to five neglect patients without a line bisection bias, 10 patients with right hemispheric lesions without neglect, and 32 healthy controls. Most interestingly, results indicated that neglect patients with a line bisection bias also overestimated segments on the left of the line (e.g., one third, one quarter) when dissecting lines into parts smaller than halves. In contrast, such segmentation biases were more nuanced when the required line segmentation was framed as a number line estimation task with either fractions or whole numbers. Taken together, this suggests a generalization of line bisection bias towards a segmentation or proportional processing bias, which is congruent with attentional weighting accounts of line bisection/neglect. As such, patients with a line bisection bias do not seem to have specific problems bisecting a line, but seem to suffer from a more general deficit processing proportions.

Rapid screening for neglect following stroke: A systematic search and European Academy of Neurology recommendations

Background and purpose

Unilateral neglect is a common cognitive disorder following stroke. Neglect has a significant impact on functional outcomes, so it is important to detect. However, there is no consensus on which are the best screening tests to administer to detect neglect in time‐limited clinical environments.

Methods

Members of the European Academy of Neurology Scientific Panel on Higher Cortical Functions, neuropsychologists, occupational therapists, and researchers produced recommendations for primary and secondary tests for bedside neglect testing based on a rigorous literature review, data extraction, online consensus meeting, and subsequent iterations.

Results

A total of 512 articles were screened, and 42 were included. These reported data from 3367 stroke survivors assessed using 62 neglect screens. Tests were grouped into cancellation, line bisection, copying, reading/writing, and behavioral. Cancellation tasks were most frequently used (97.6% of studies), followed by bisection, copying, behavioral, and reading/writing assessments. The panel recommended a cancellation test as the primary screening test if there is time to administer only one test. One of several cancellation tests might be used, depending on availability. If time permits, one or more of line bisection, figure copying, and baking tray task were recommended as secondary tests. Finally, if a functional and ecological test is feasible, the Catherine Bergego Scale was recommended. Overall, the literature suggests that no single test on its own is sufficient to exclude a diagnosis of neglect. Therefore, the panel recommended that multiple neglect tests should be used whenever possible.

Conclusions

This study provides consensus recommendations for rapid bedside detection of neglect in real‐world, clinical environments.

A Patient With Bipolar Illness and Her Neuropsychological Signature

This article describes a case study in which neuropsychological assessment was carried out on a 30-year-old, previously diagnosed, bipolar female to determine existence of specific deficits in cognitive function. The patient, whose mood cycles were 12 hours to 24 hours, was subsequently evaluated 8 hours per day for 5 consecutive days (a complete work week of neuropsychological assessment). Neuropsychological results showed motor slowing, right hemispheric dysfunctioning, and memory problems during depressive periods and attentional and executive problems during hypomanic and manic periods. The most normal performance was found during euthymic periods. In addition, left and right hemi visual neglect, aphasia, and sensorimotor problems were present across all mood states. Treatment implications are subsequently described.

Feasibility of a Semi-computerized Line Bisection Test for Unilateral Visual Neglect Assessment

BACKGROUND

Commonly used paper-and-pencil based test modalities for assessing the degree of unilateral visual neglect (ULN) in patients with hemispheric cerebral lesions consume human resources with a significant inter and intra-rater variability.

OBJECTIVE

To explore the feasibility of a semi-computerized electronic-pen based ULN assessment system (e-system) to improve assessment quality without altering the conventional user interface.

MATERIALS AND METHODS

Thirty cognitively healthy participants (HG) and 11 participants diagnosed with right-hemispheric lesion and unilateral visual neglect (NG) were recruited to evaluate the e-system. Line bisection tests (LBT) were repeatedly conducted twice for the inter-rater and intra-rater (reliability) comparisons. The LBT results were assessed by the e-system and the golden standard methods (manual rater assessment). The percent deviation (%), assessment duration (sec), and number of neglected line (each) were evaluated.

RESULTS

The inter-rater comparisons of the assessed deviation (%) variable showed excellent interrater reliabilities (CCCs) ranging from .84 (.59 to .95 (p < .001)) to .99 (.90 to .99 (p < .001)) for HG and NG. The Bland Altman mean difference (B-A) plots with bias (95% LOA (limits of agreement)) showed similar agreements between the e-system and the raters ranging from -.04 % (-2.10 to 1.97) to 1.30 % (-2.23 to 4.84) for HG and NG. The effect sizes (ES), which show similarities between the assessment methods, yielded smaller ranges from .01 to .30 for HG and NG. The reliability (test-retest) comparisons showed similar assessment results between the e-system, rater 1, and rater 2. The manual rater assessment time ranging from 5.85 to 6.00 minutes and inter- and intraassessment variations were virtually eliminated with the e-system.

CONCLUSION

The semi-computerized system with the conventional paper-and pencil user-interface showed valid and reliable assessment results. It may be a feasible replacement for the manual rater assessment modality even in a clinical setting.

Ocular–visual defect and visual neglect in stroke patients – A report from Kathmandu, Nepal

Purpose

To find out the type of visual defects, ocular defects or visual neglect occurring in patients with stroke.

Methods

In this cross-sectional study including 40 subjects diagnosed as stroke, assessment included visual acuity with the Sheridan-Gardner chart, objective and subjective refraction, duction and version eye movement, cover test at distance and near, anterior segment examination with the slit lamp, posterior segment examination after pupil dilatation, color vision test with the Farnsworth D-15 test, diplopia charting, the Hess charting, and visual field examination on Goldmann perimetry. 33 subjects (82.5%) having stroke underwent star cancellation test for visual neglect evaluation. Chi-square test with Yate's correction was performed to evaluate associations between visual neglect and neurological findings.

Results

The mean age of the subjects was 52.1 ± 15.7 years with male/female ratio of 0.7. Neurological findings included hemiplegia/hemiparesis in 84.8%, ischemic stroke in 80%, left hemisphere involvement in 60%, and cortical area involvement in 65%. Ocular finding included extraocular muscle palsy in 17.5%, exotropia in 12.5%, and ptosis in 7.5%. Co-morbid ocular findings such as cataract, retinopathy, and age-related macular degeneration were also reported. Visual neglect was present in 54.5% subjects predominantly affecting the left side.

Conclusion

This study reports the relationship between ocular–visual disorders and stroke. There should be a formal screening for visual problems in stroke patients in hospital and rehabilitation settings.

Visual neglect following stroke: current concepts and future focus

Visual neglect is a common, yet frequently overlooked, neurological disorder following stroke characterized by a deficit in attention and appreciation of stimuli on the contralesional side of the body. It has a profound functional impact on affected individuals. A assessment and management of this condition are hindered, however, by the lack of professional awareness and clinical guidelines. Recent evidence suggests that the underlying deficit in visual attention is due to a disrupted internalized representation of the outer world rather than a disorder of sensory inputs. Dysfunction of the cortical domains and white-matter tracts, as well as inter-hemispheric imbalance, have been implicated in the various manifestations of visual neglect. Optimal diagnosis requires careful history-taking from the patient, family, and friends, in addition to clinical assessment with the line bisection test, the star cancellation test, and the Catherine Bergego Scale. Early recognition and prompt rehabilitation employing a multidisciplinary approach is desirable. Although no treatment has been definitively shown to be of benefit, those with promise include prism adaptation, visual scanning therapy, and virtual reality-based techniques. Further high quality research to seek optimum short- and long-term rehabilitative strategies for visual neglect is required.

A virtual reality test battery for assessment and screening of spatial neglect

BACKGROUND

There is a need for improved screening methods for spatial neglect.

AIM

To construct a VR-test battery and evaluate its accuracy and usability in patients with acute stroke.

METHOD

VR-DiSTRO consists of a standard desktop computer, a CRT monitor and eye shutter stereoscopic glasses, a force feedback interface, and software, developed to create an interactive and immersive 3D experience. VR-tests were developed and validated to the conventional Star Cancellation test, Line bisection, Baking Tray Task (BTT), and Visual Extinction test. A construct validation to The Rivermead Behavioral Inattention Test, used as criterion of visuospatial neglect, was made. Usability was assessed according to ISO 9241-11.

RESULTS

Thirty-one patients with stroke were included, 9/31 patients had neglect. The sensitivity was 100% and the specificity 82% for the VR-DiSTRO to correctly identify neglect. VR-BTT and VR-Extinction had the highest correlation (r² = 0.64 and 0.78), as well as high sensitivity and specificity. The kappa values describing the agreement between traditional neglect tests and the corresponding virtual reality test were between 0.47-0.85. Usability was assessed by a questionnaire; 77% reported that the VR-DiSTRO was 'easy' to use. Eighty-eight percent reported that they felt 'focused', 'pleased' or 'alert'. No patient had adverse symptoms. The test session took 15 min.

CONCLUSIONS

The VR-DiSTRO quickly and with a high accuracy identified visuospatial neglect in patients with stroke in this construct validation. The usability among elderly patients with stroke was high. This VR-test battery has the potential to become an important screening instrument for neglect and a valuable adjunct to the neuropsychological assessment.

Clinical assessment of hemispatial neglect: evaluation of different measures and dimensions

The multidimensional nature of the neglect syndrome constitutes a challenge for clinical assessments. This study evaluates the sensitivity of different clinical measures to detect neglect and explores ways to evaluate the diversity of the syndrome in a clinical sample. An extensive battery of tests was used to examine aspects of visuospatial, representational, and personal neglect. A total of 31 normal control participants and 34 patients with right hemisphere stroke were examined 16.8 days post-stroke, on average. Of the patients, 24 showed neglect in at least one task. The Random shape cancellation test, Star cancellation, and two line bisection tasks appeared to be the most sensitive tests of visuospatial neglect. Personal neglect and neglect in far space occurred only together with extrapersonal neglect. Besides near space, other spatial aspects of neglect are important to consider in clinical assessments, but standardized methods are needed. In this patient group a minimum of 10 tests were needed to cover various aspects of detection, dissociations, and severity of neglect. A multifactorial approach in clinical testing of neglect is recommended.

Assessment of spatial attention after brain damage with a dynamic reaction time test

Lateralized spatial biases after brain damage are commonly assessed using batteries of paper-and-pencil tests. These tests hardly allow quantification of performance in different locations in space, and they tend to lose sensitivity along the course of recovery. We tested the dynamic Starry Night Test (SNT), a novel computerized test measuring reaction time and detection accuracy for visual target stimuli in a dynamic background, in 32 inpatients with right hemisphere stroke (RHS), 16 patients with left hemisphere stroke (LHS), and 9 healthy controls. As a group, only the RHS patients were significantly slower to respond to contralesional targets. Individually, 21 (66%) RHS patients and 5 (31%) LHS patients showed statistically significant contralateral deficits. In a number of RHS patients the SNT was more sensitive to the ipsilesional bias of spatial attention than the Behavioral Inattention Test (BIT), a standardized paper-and-pencil test battery of unilateral spatial neglect. Two illustrative case reports show that the dynamic SNT, but not the BIT, was sensitive to the spatial deficit in recovered patients, one of whom was involved in repeated car accidents. The SNT overcomes serious shortcomings of paper-and-pencil tests of unilateral neglect. It provides a simple quantitative tool for monitoring the natural and treatment-induced recovery of patients.

Effektivität experimenteller und rehabilitativer Interventionen bei visuellem Neglect - Eine Metaanalyse

Zusammenfassung: Präsentiert wird eine Metaanalyse zur Wirksamkeit neuropsychologischer Interventionen bei visuellem Hemineglect. Es wurden die publizierten Outcome-Ergebnisse Experimental- und Rehabilitationsstudien zur Modifikation und Modulation des Neglectsyndroms quantitativ integriert. 133 identifizierte Studien wurden in sechs Klassen eingeteilt. Studien-, Interventions- und Patientenmerkmale dienten zur Bestimmung moderierender Einflüsse, über Sensitivitätsanalysen wurde die Robustheit der Ergebnisse abgeschätzt. Die mittlere Gesamteffektivität der Interventionen liegt um 0.8 Standardeinheiten Symptomverbesserung gegenüber dem Prä-Niveau bei Patienten mit chronischem Neglect. Spontanremissionseffekte sind aufgrund der durchschnittlichen Erkrankungsdauer als gering zu veranschlagen und konnten empirisch nicht nachgewiesen werden. Explorationstrainings, personale Intervention und Hinweisreiz-Verfahren stellen sich als überdurchschnittlich effektiv und signifikant effektiver als bloße Reduktion der Umweltanforderungen heraus.

Selbstinstruktionstraining bei visuellem Neglect - Eine einzelfallanalytische Untersuchung

Zusammenfassung: Patienten mit Neglect sollten sich bei Aufgaben aus dem Bereich der Neglectdiagnostik mit einer Selbstverbalisationstechnik dazu anleiten, die vernachlässigte linke Seite zu beachten. Das methodische Vorgehen sah eine Einzelfallanalyse mit direkter Replikation vor. Pro Person wurden 25 Sitzungen absolviert. Dem Problem der Mehrfachvorgabe von Aufgaben, das sich bei einer Einzelfallanalyse stellt, wurde begegnet, indem Parallelversionen der Testmaterialien erstellt wurden. Das Selbstinstruktionstraining reduzierte die neglecttypischen Fehler signifikant. Die Hypothese, daß die eingeführte Behandlung eine Besserung der Symptomatik bedingt, konnte sich zudem in einer Replikationsstudie bewähren. Offen bleibt, ob die Selbstinstruktionen der Patienten spezifisch auf einen Verhaltensbereich wirkten oder aber auf andere generalisierten.

Prediction of gait velocity in ambulatory stroke patients during rehabilitation

OBJECTIVE

To quantify prediction of gait velocity in ambulatory stroke patients during rehabilitation.

DESIGN

Single group (n = 42) at the beginning of rehabilitation (Test 1) and 8 weeks later (Test 2).

SETTING

Inpatient rehabilitation.

PATIENTS

Unilateral first stroke; informed consent; able to walk 10 meters.

MEASURES

INDEPENDENT VARIABLES

Gait velocity at Test 1, age, time from stroke to Test 1, side of lesion, neglect.

DEPENDENT VARIABLES

Gait velocity at Test 2, gait velocity change.

RESULTS

The correlation between initial gait velocity and gait velocity outcome at Test 2 was of moderate strength (r2 = .62, p<.05). However, even at its lowest, the standard error of prediction for an individual patient was 9.4 m/min, with 95% confidence intervals extending over a range of 36.8 m/min. Age was a weak predictor of gait velocity at Test 2 (r2 = -.10, p<.05). Gait velocity change was poorly predicted. The only significant correlations were initial gait velocity (r2 = .10, p<.05) and age (r2 = .10, p<.05).

CONCLUSION

While the prediction of gait velocity at Test 2 was of moderate strength on a group basis, the error surrounding predicted values of gait velocity for a single patient was relatively high, indicating that this simple approach was imprecise on an individual basis. The prediction of gait velocity change was poor. A wide range of change scores was possible for patients, irrespective of their gait velocity score on admission to rehabilitation.

Diagonal neglect on cancellation

Patients with right hemisphere injury frequently neglect to cancel targets primarily in the left part of the page nearest the body. Since this region is diagonally opposite the area from where such patients usually begin cancelling, near left ('diagonal') neglect may be consequent to stimulus order effects ('fatigue'). We evaluated the persistence of near left neglect in nine stroke patients when they had to cancel either the near or the far half of the page before proceeding to the other half. Our results showed that near left neglect on the page was largely unaffected by cancellation order. Furthermore, a near left gradient of omissions was established within both radial (near and far) halves of the page, as well as for the entire page. Our findings suggest that diagonal cancellation neglect is unrelated to fatigue and reflects a consistent, two-dimensional disorder of spatial attention. Such neglect may be related to the extent of the visible stimulus array, as well as to the array's location in egocentric space.