Development of the Halifax Visual Scanning Test: A New Measure of Visual-Spatial Neglect for Personal, Peripersonal, and Extrapersonal Space

Identifying spatial neglect - an updated systematic review of the psychometric properties of assessment tools in adults post-stroke

Spatial neglect commonly occurs after a stroke, resulting in diverse impacts depending on the type and severity. There are almost 300 tools for assessing neglect, yet there is a lack of knowledge on the psychometric properties of these tools. The objective of this systematic review, registered on Prospero (CRD42021271779), was to determine the quality of the evidence for assessing spatial neglect, categorized by neglect subtype. The following databases were searched on 3rd May 2022 from database inception: Ovid Emcare, Embase, Ovid MEDLINE, APA PsycINFO, Web of Science (SCI-EXPANDED; SSCI; A&HCI; ESCI) and Scopus. All primary peer-reviewed studies (>5 participants) of adults post stroke, reporting any psychometric property of 33 commonly used neglect assessment tools were included. The COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) risk of bias tool was used to assess the methodological quality of the studies and summarize the psychometric properties of each tool. 164 articles were included, with a total of 12,463 people with stroke. The general quality of the evidence was poor and no one tool had high-quality evidence of both validity and reliability. Eleven tools show some promise as they meet the minimum criteria for good measurement properties for both validity and reliability.

Does prism adaptation treatment reduce spatial neglect and improve function?

The potential of using prism adaptation for treating spatial neglect (SN) was questioned when recent meta-analyses found inconsistent evidence. However, analyses of clinical datasets support the use of prism adaptation treatment (PAT) in reducing SN and improving function. The main objective of this review is to evaluate the current state of the evidence of PAT therapeutic effects, identify knowledge gaps, and make suggestions to guide further research and support clinical decision-making. We used the framework of the National Institutes of Health (NIH) Stage Model for Behavioral Intervention Development which provides guidance on best practices for developing effective behavioral interventions that can be implemented in real-world settings. This model emphasizes the interplay between mechanisms underlying therapeutic effects ("who" should receive the treatment and "how" best does it work?) and considerations of adaptability and feasibility in real-world settings. The present critical review led to the following conclusion: the use of the NIH Stage Model reveals the heterogeneity of PAT studies and challenges in advancing PAT as an effective intervention. The key mechanisms such as prism strength, treatment intensity, arm visibility and activities during treatment, and evaluation methods lack consensus. Therefore, clinical research teams must continue to collect evidence to determine critical mechanisms and the optimal protocol. Further research identifying the optimal PAT protocol is needed before another meta-analysis on PAT's clinical efficacy should be conducted again.

A scoping review and critique of the Input-Output subtyping dimension of spatial neglect

Spatial neglect is a common and debilitating disorder after stroke whereby individuals have difficulty reporting, orienting, and/or responding to the contralesional side of space. Given the heterogeneity of neglect symptom presentation, various neglect subtypes have been proposed to better characterize the disorder. This review focuses on the distinction between Input neglect (i.e., difficulty perceiving and/or attending to contralesional stimuli) and Output neglect (i.e., difficulty planning and/or executing movements toward contralesional stimuli). Conceptualizations of Input and Output neglect have varied considerably. We provide a novel summary of the terminology, measurement approaches, and neural correlates of these subtypes. A protocol detailing our systematic scoping review strategy is registered on the Open Science Framework (https://osf.io/bvtxf/). For feasibility and greater comparability across studies, we limited our inclusion criteria to tasks focused on visual stimuli and upper-limb movements. A total of 110 articles were included in the review. Subtyping tasks were categorized based on whether they mainly manipulated aspects of the input (i.e., congruence of visual input with motor output, presence of visual input) or the output (i.e., modality, goal, or direction of output) to produce an Input-Output subtype dissociation. We used our review results to identify four main critiques of this literature: 1) lack of consistency/clarity in conceptual models; 2) methodological issues of dissociating Input and Output subtypes; 3) a need for updated neural theories; and 4) barriers to clinical application. We discuss the lessons learned from this subtyping dimension that can be applied to future research on neglect subtype assessment and treatment.

An International and Multidisciplinary Consensus on the Labeling of Spatial Neglect Using a Modified Delphi Method

Survivors of neurologic injury (most commonly stroke or traumatic brain injury) frequently experience a disorder in which contralesionally positioned objects or the contralesional features of individual objects are often left unattended or underappreciated. The disorder is known by >200 unique labels in the literature, which potentially causes confusion for patients and their families, complicates literature searches for researchers and clinicians, and promotes a fractionated conceptualization of the disorder. The objective of this Delphi was to determine if consensus (≥75% agreement) could be reached by an international and multidisciplinary panel of researchers and clinicians with expertise on the topic. To accomplish this aim, we used a modified Delphi method in which 66 researchers and/or clinicians with expertise on the topic completed at least 1 of 4 iterative rounds of surveys. Per the Delphi method, panelists were provided with results from each round prior to responding to the survey in the subsequent round with the explicit intention of achieving consensus. The panel ultimately reached consensus that the disorder should be consistently labeled spatial neglect. Based on the consensus reached by our expert panel, we recommend that researchers and clinicians use the label spatial neglect when describing the disorder in general and more specific labels pertaining to subtypes of the disorder when appropriate.

Can prism adaptation effects generalize to wheelchair maneuvering?

BACKGROUND

While prism adaptation (PA) has been recognized as a promising tool for treating spatial neglect, implementation as a standard treatment in clinical care has been lagging. Limited evidence for the generalization of after-effects to everyday activities has been a barrier towards implementation.

OBJECTIVES

This study examined whether a home-friendly standardized PA protocol (Peg-the-Mole, PTM) induces after-effects that can transfer to wheelchair maneuvering. We also examined the impact of using constant (1 starting hand position) or variable (3 starting hand positions) training conditions on the transfer of after-effects to wheelchair maneuvering.

METHODS

Sixty participants were randomly assigned to one of four PTM conditions: 1) prisms/constant training; 2) prisms/variable training; 3) sham goggles/constant training; 4) sham goggles/variable training.

RESULTS

The use of PTM with rightward shifting prisms induced after-effects on proprioceptive and visual pointing outcome tasks. Groups using PTM with prism goggles showed a leftward shift in their position within a wheelchair course and a reduction in the number of right-sided collisions. The training condition did not have an impact on the transfer of after-effects to wheelchair driving.

CONCLUSION

PTM is a clinically appealing PA protocol that induces after-effects that can transfer to an everyday activity relevant to patients with neglect.