The Visual Scanning Test: a Neuropsychological Tool to Assess Extrapersonal Visual Unilateral Spatial Neglect

The Visual Scanning Test (VST) involved a visual search for a target between similar visual distractors, projected in the far space, so as to simulate the search within a visual field. It is overall composed by four trials, each trial contained 20 cases and made up by 20 stimuli. On about the 80% of cases, the test provided the presence of target in the left, center or in right hemispace. In the remaining 20% of cases, the test provided the presence of a catch trial (absence of the target), to assess the presence of frontal disturbances or malingering. The test is constructed according to an increasing attentional load for the target on the left-hemispace. Participants, sitting in front a blank wall, were required to actively and free explore the projected visual field to search for the visual target, naming its identification (saying YES or NO). During the task, the examiner annotated the reaction times and the errors.