Increased Cognitive Load Reveals Unilateral Neglect and Altitudinal Extinction in Chronic Stroke

Abstract

Objective: Neuropsychological studies suggest that the ability to compensate for the presence of spatial neglect highly depends on the attentional resources a patient can rely on. The present research aimed to study neglect in situations where attentional resources are limited due to multitasking. Method: We examined two patients more than 3 years after a right-hemispheric stroke. Both had received neuropsychological rehabilitation for left neglect and did not show any impairment in standard tests. We used a dual-task paradigm combining a peripheral target detection task with a central shape recognition task. Peripheral targets could appear in left/right positions but also in lower/upper positions. Results: In patient #1, dual-task condition exacerbated left neglect and extinction. Patient #2 did not show any sign of neglect along the horizontal axis, but omitted half of the lower targets when they were presented simultaneously with upper targets under dual-task condition. This behavior reflects altitudinal extinction as the detection of single targets appearing either in upper or lower position was preserved. Conclusion: The present findings show that dual-tasking is a sensitive tool for the quantitative and qualitative assessment of spatial attention deficits, which are often overlooked by standard methods, especially in chronic stage. (JINS, 2019, 25, 644–653)

Dual-Task in Large Perceptual Space Reveals Subclinical Hemispatial Neglect

“…However, most previous studies (e.g. Andres et al, 2019;Blini et al, 2016;Bonato, 2015;Bonato et al, 2010Bonato et al, , 2012, which have compared more complex computer-based tasks to pen-and-paper methods in the peripersonal space, have found that the computer-based tasks are more sensitive in identifying mild neglect. Which factors contributed to both large-screen tasks being sensitive in identifying RH patients' subclinical neglect?…”

“…Hence, a large test field may be one of the components that increase sensitivity. Further, a dual-task assignment presumably eliminates the typical top-down coping mechanism and brings out symptoms that would otherwise be compensated for (Andres et al, 2019;Bonato, 2015;Robertson & Frasca, 1992;Robertson & Manley, 2004;van Kessel et al, 2013). Increases in task demands need not be either visuospatial or attentional in order to improve assessment (Mennemeier, Morris, & Heilman, 2004;Ricci et al, 2016).…”

“…Several previous studies (e.g. Andres et al, 2019;Blini et al, 2016;Bonato, 2015;Bonato et al, 2010Bonato et al, , 2012van Kessel et al 2013) have already noted that a dual-task paradigm is in itself more sensitive than a single task in bringing out mild neglect. Therefore, the effect of the large visual field would require particular attention in future studies.…”

“…Various studies have compared new assessment methods with traditional tests (e.g. Deouell et al, 2005;Kim et al, 2010;Tanaka et al, 2005;Ulm et al, 2013;van Kessel et al, 2010), and computerized dual-tasks with single tasks (Andres et al, 2019;Blini et al, 2016;Bonato, 2015;Bonato et al, 2010Bonato et al, , 2012van Kessel et al 2013). However, to our knowledge, there is only limited research comparing different computerized dual-tasks.…”

Spatial Neglect Subtypes, Definitions and Assessment Tools: A Scoping Review

“…New tools for identifying neglect are continually being developed, possibly due to the existing tools not being able to detect milder forms of neglect, or an inability to detect the different neglect subtypes. The increasing number of virtual reality and computer-based tools being developed have the potential to increase the task demands, such as dual-task paradigms or speeded reaction time tests, in order to identify mild or subclinical neglect (121)(122)(123). However, many of these tools are not feasible to use in clinical settings due to the complex setup or cost requirements.…”