Horizontal visual search in a large field by patients with unilateral spatial neglect

Abstract

Abstract:In this study, we investigated the horizontal visual search ability and pattern of horizontal visual search in a large space performed by patients with unilateral spatial neglect (USN). Subjects included 9 patients with right hemisphere damage caused by cerebrovascular disease showing left USN, 9 patients with right hemisphere damage but no USN, and 6 age-matched healthy individuals with no history of brain damage.The number of visual search tasks accomplished was recorded in the first experiment, and the neck rotation angle was continuously measured during the task, and quantitative data of the measurements were collected. The results revealed a strong correlation between the number of visual search tasks accomplished and the total Behavioral Inattention Test Conventional Subtest (BITC) score in subjects with right hemisphere damage. In both USN and control groups, the head position during the visual search task showed a balanced bell-shaped distribution from the central point on the field to the left and right sides. Our results indicate that compensatory strategies along with the cervical rotation may be effective to improve the search ability and achieve balance towards the neglected side.4

Head Position of Patients with Right Hemisphere Damage during a Visual Search Task in a Large Field

“…In a previous study, we reported a strong correlation between the number of visual search tasks accomplished in a large space and the total BITC score, and no significant difference was observed in the neck rotation angle as well as the average and maximum values of the group without USN including normal healthy adults and individuals with USN, under experimental settings [7]. In addition, the neck rotation pattern of the group with USN presented a tendency to search in the right space [7]. In this experimental setting, the non-USN group with right hemisphere damage and healthy adult group obtained the highest score (36 points) in the visual search task in a large space.…”

“…By analyzing horizontal visual search ability, head position, and neck rotation pattern during the search task in a large space, we reported a strong correlation between the number of visual search tasks performed in a large space and the total BITC score. Furthermore, no significant difference was observed with respect to the neck rotation angle as well as the average and maximum values of the two groups [7].…”

“…We have previously reported on the diversity of USN symptoms, wherein we focused on a sound lateralization ability using auditory tasks [6], as well as on a visual search ability and horizontal neck rotation angle during visual search tasks in a large space [7]. In our previous study, we divided subjects into two groups, one with USN and one without USN, based on the score of Behavioural Inattention Test Conventional Subtest (BITC).…”

“…The present study aimed to understand the symptoms of USN, and develop more effective rehabilitation program. The details of the participants, methods, experimental settings, and a figure are the same as in our previous report [7].…”

Through the Eyes of Neglect Patients: A Preliminary Eye-Tracking Study of Unilateral Spatial Neglect

“…Individuals with USN tend to compensate visual search capability and achieve balance on the neglected side with cervical rotations (6,7). Spatial and temporal patterns of visual search during cancellation, visuomotor, and visual search tasks have been proposed to improve (8).…”