Visual Scanning Training for Neglect after Stroke with and without a Computerized Lane Tracking Dual Task

Abstract

Neglect patients typically fail to explore the contralesional half-space. During visual scanning training, these patients learn to consciously pay attention to contralesional target stimuli. It has been suggested that combining scanning training with methods addressing non-spatial attention might enhance training results. In the present study, a dual task training component was added to a visual scanning training (i.e., Training di Scanning Visuospaziale – TSVS; Pizzamiglio et al., 1990). Twenty-nine subacute right hemisphere stroke patients were semi-randomly assigned to an experimental (N = 14) or a control group (N = 15). Patients received 30 training sessions during 6 weeks. TSVS consisted of four standardized tasks (digit detection, reading/copying, copying drawings, and figure description). Moreover, a driving simulator task was integrated in the training procedure. Control patients practiced a single lane tracking task for 2 days a week during 6 weeks. The experimental group was administered the same training schedule, but in weeks 4–6 of the training, the TSVS digit detection task was combined with lane tracking on the same projection screen, so as to create a dual task (computerized visual reaction time task designed for training). Various neglect tests and driving simulator tasks were administered before and after training. No significant group and interaction effects were found that might reflect additional positive effects of dual task training. Significant improvements after training were observed in both groups taken together on most assessment tasks. Ameliorations were generally not correlated to post-onset time, but spontaneous recovery, test–retest variability, and learning effects could not be ruled out completely, since these were not controlled for. Future research might focus on increasing the amount of dual task training, the implementation of progressive difficulty levels in driving simulator tasks, and further exploration of relationships between dual task training and daily functioning.

Component deficits of visual neglect: “Magnetic” attraction of attention vs. impaired spatial working memory

“…These findings support and specify multi-component models of neglect, which postulate that neglect behavior results from variable combinations of component deficits in different patients Bartolomeo, 2007Binder et al, 1992;Heilman et al, 2002;M. M. Mesulam, 2002;Vallar, 1998). Specifically, our multiple single-case approach was able to identify patients with variable severity of combined MA and SWM deficits.…”

“…When asked to cross out targets scattered on a sheet, neglect patients typically restrict their exploration to the right part of the sheet and omit cancelling left-sided targets (Albert, 1973). The precise mechanisms leading to neglect behavior are object of debate since almost a century, but some consensus is now emerging that distinct component deficits of neglect may variously dissociate in some patients Binder, Marshall, Lazar, Benjamin, & Mohr, 1992;Charras et al, 2012;Heilman, Watson, & Valenstein, 2002;Mesulam, 1985;Mesulam, 2000;Vallar, 1998), or combine and interact in others (Bartolomeo, 2007;Coulthard, Parton, & Husain, 2007;Gainotti, D'Erme, & Bartolomeo, 1991;Karnath, 1988). As a consequence, the focus of research is now shifting to the identification of these component deficits, to the study of their modes of interactions and the exploration of their anatomical bases.…”

Simulated driving: The added value of dynamic testing in the assessment of visuo‐spatial neglect after stroke

“…The simulated driving task (Van Kessel, Geurts, Brouwer, & Fasotti, 2013;Van Kessel et al, 2010) consisted of a driving scene projected on a large screen (2.13 m 9 3.18 m; Figure 1). A straight road without intersections or oncoming traffic was projected on the screen.…”

Novel insights in rehabilitation of neglect

“…They indicate that it is unclear at present which characteristics of VR are most important and that it is unknown whether effects can be sustained in the longer term. In neglect patients, VR has been recently applied both for diagnostic purposes (Broeren et al, 2007;Buxbaum et al, 2008Buxbaum et al, , 2012Jannink et al, 2009;Kim et al, 2010;Van Kessel et al, 2010, 2013aFordell et al, 2011;Peskine et al, 2011;Dvorkin et al, 2012) and as a rehabilitation tool (Webster et al, 2001;Castiello et al, 2004;Katz et al, 2005;Ansuini et al, 2006;Kim et al, 2007Kim et al, , 2011Smith et al, 2007;Sedda et al, 2012;Van Kessel et al, 2013b). In their review on the use of VR in the assessment and treatment of neglect, Tsirlin et al (2009) argue that an important benefit of VR technologies is that they provide rich and realistic environments with a high level of control over their parameters and thus allow for training in a safe and cost effective way.…”

“…In fact, both groups showed significant but similar improvement in performance on a test of driving-related visual attention skills after training and benefits lasted up to 6 months after stroke. Van Kessel et al (2013b) conducted a study in which visual scanning training (based on Pizzamiglio et al, 1990Pizzamiglio et al, , 1992) was compared to an experimental condition consisting of a combination of visual scanning training and a VR driving simulator task. Twenty-nine subacute right hemisphere stroke patients were semi-randomly assigned to one of both conditions.…”