Visual search in stroke patients using a digitized object cancellation test without markers
Summary
Stroke patients can have problems regarding visual search, which could affect rehabilitation and activities of daily living (ADL). Lesions in the right hemisphere are associated with disorganized visual search. Visual search can be evaluated with a cancellation test, in which targets that are embedded in a set of distractors, are cancelled. The targets are marked in order to keep track of the search performance. In ADL however, no visual markers appear during visual search. In this study, visual search in stroke patients with lesions in the left hemisphere (LH) or the right hemisphere (RH) was explored with a digitized cancellation test with and without visual markers. The amount of omitted targets, perseverations, intersections, consistency in search direction and the duration of the test performance were extracted to evaluate visual search performance. It was found that more omissions and perseverations were made when no markers were provided. In contrast,
search direction was more consistent. Furthermore, patients with lesions in the RH made more omissions, more intersections and showed a less consistent search direction on both versions. In addition, patients with lesions to the RH made more perseverations when no markers appeared in the test.