Immediate effects of head-mounted display adaptation in cases of unilateral spatial neglect: study of straight-ahead pointing

Abstract

This study aimed to clarify the effect of an adaptation of a deviation of the visual field in three axes on spatial cognition in patients with unilateral spatial neglect and distorted spatial perception in three dimensions. [Participants and Methods] Fifteen patients with cerebrovascular disease and symptoms of unilateral spatial neglect were included. Forty-eight pointing movements with a camera attached to a head-mounted display changed in three axes were compared with the control condition in which the camera was deflected only in the horizontal plane as with the prism adaptation. The main outcome measures were subjective straight-ahead pointing, line bisection, line cancellation, and star cancellation. [Results] The head-mounted display adaptive therapy was performed under conditions that varied in all three axes. The results indicated that it was possible to deflect the subjective straight-ahead pointing position to the lower left direction. [Conclusion] In contrast to the prism adaptation, which deflects the visual field in a single axis in the horizontal plane, the tri-axial adaptation corrected the median cognition in the left-right direction as well as the cognition of the body center, including the vertical direction.

Effects of unilateral neck muscle vibration on standing postural orientation and spatial perception in healthy subjects based on stimulus duration and simultaneous stimulation of trunk muscles

“…To assess spatial perception, SSA was measured using a 32” (1375 × 767 pixels) touch panel (NEWCOM Inc., Saitama, Japan) [ 25 ], which was placed in front of each participant. The position of the touch panel was adjusted such that when a participant reached it with their right index finger in an upright sitting position, the distance could be achieved with slight elbow flexion without excessive forward bending or trunk rotation.…”

“…Subsequently, the participants were instructed to touch the location on the touch panel with their index fingers, which they thought was directly in front of the manubrium of sternum. After two practice sessions with closed eyes, the exercise was repeated eight times, and the mean position in the ML and AP planes [mm] on the touch panel were calculated using Grid software (NEWCOM Inc., Saitama, Japan) [ 25 ]. During the practice sessions, we checked only the procedures and gave no feedback on the results.…”