title: Assessment of visual space recognition of patients with unilateral spatial neglect and visual field defects using a head mounted display system.
abstract: [Purpose] The purpose of this study was the development of a method for presenting diverse visual information and assessing visual space recognition using a new head mounted display (HMD) system. [Subjects] Eight patients: four with unilateral spatial neglect (USN) and four with visual field defects (VFD). [Methods] A test sheet was placed on a desk, and its image was projected on the display of the HMD. Then, space recognition assessment was conducted using a cancellation test and motion analysis of the eyeballs and head under four conditions with images reduced in size and shifted. [Results] Leftward visual search was dominant in VFD patients, while rightward visual search was dominant in USN patients. The angular velocity of leftward eye movement during visual search of the right sheet decreased in both patient types. Motion analysis revealed a tendency of VFD patients to rotate the head in the affected direction under the left reduction condition, whereas USN patients rotated it in the opposite direction of the neglect. [Conclusion] A new HMD system was developed for presenting diverse visual information and assessing visual space recognition which identified the differences in the disturbance of visual space recognition of VFD and USN patients were indicated.
authors.affiliation: The Graduate School of Information Science and Technology, Hokkaido University: N14, W9, Kita-ku, Sapporo 060-0814, Japan; Department of Rehabilitation, Sapporo Shuyukai Hospital, Japan.
authors.forename: Shunichi
authors.initials: S
authors.lastname: Sugihara
authors.affiliation: Department of Physical Therapy, Faculty of Health Sciences, Hokkaido University of Science, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Department of Physical Therapy, Faculty of Health Sciences, Hokkaido University of Science, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Miyasaka
authors.affiliation: Department of Human Science and Informatics, School of Biological Science and Engineering, Tokai University, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Izumi
authors.affiliation: The Graduate School of Information Science and Technology, Hokkaido University: N14, W9, Kita-ku, Sapporo 060-0814, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Shimizu
keywords: Unilateral spatial neglect; Visual field defects; Visual space recognition