Gaze scanning by walking people with visual field loss

项目总结

Project Summary In mobility tasks, we look around the environment usually by moving both eye and head. Since eye movement amplitude is usually small (<15º), the contribution of head movement to the gaze scanning may be larger and more important. For patients with visual field loss in walking, our previous studies did not find their eye movements dispersed wider than normally sighted. A remaining question is whether the patients primarily scan by moving their heads. However, due to the technically challenges in head tracking, research on head movement behaviors in outdoor walking scenarios is relatively sparse than that for eye movement. In a few studies that do include head tracking, the investigation was either conducted in virtual environment, or the head movements were only qualitatively assessed. In this project, we propose to conduct secondary analysis of data collected in previous federally funded research projects, in which we recorded the eye-in-head and scene videos with a head mounted camera in patients with visual field loss as well as normally sighted controls, as they walked on busy streets in Boston downtown area. To extract head movements from the scene videos, we will use the latest 3D visual mapping technology, which has substantially advanced in recent years as it is been applied to self-driving research nowadays. This would be the first time the complete gaze scanning patterns including the head movements of the visually impaired people in an open outdoor environment are quantitatively evaluated. The previously collected videos also include an intervention condition, where the patients with hemi-field loss walking while wearing a prism field expander. By comparing the gaze scanning behavior with and without the field expander, we would be able to understand how gaze scanning behaviors can be intervened. The knowledge gained from this research can potentially inform the low vision rehabilitation community.