A new method to measure higher visual functions in an immersive environment.

Area of Science:

• Neuroscience
• Vision Science
• Human-Computer Interaction

Background:

• Higher visual functions encompass object recognition, color/shape perception, and motion detection.
• Traditional tests lack assessment of interhemispheric interaction and hemifield-specific visual function.
• Current methods do not differentiate visual performance between contralesional and ipsilesional visual hemifields.

Purpose of the Study:

• To develop and evaluate a novel measurement setup for assessing higher visual functions in an immersive environment.
• To adapt visual stimuli for projection onto a non-flat hemispherical screen using a distortion algorithm.
• To assess the usability and acceptance of the developed visual function testing battery.

Main Methods:

• Developed a real-time system for comparing visual stimuli (shape, size, orientation, motion) in either visual hemifield.
• Implemented the system in a hemispherical immersive environment to account for peripheral/central vision and visual field loss.
• Utilized a distortion algorithm to correct image warping on the curved screen and conducted a pilot study with 57 healthy volunteers.

Main Results:

• Distortion algorithm achieved >97% structural similarity between original and warped images.
• Pilot study demonstrated high accuracy in size (0.18°), shape (0.19°), orientation (2.56°), speed (0.33°/s), and motion direction (7.41°) discrimination.
• Satisfaction Questionnaire indicated high acceptance and usability of the developed testing battery.

Conclusions:

• A novel method for measuring higher visual functions in an immersive setting has been successfully developed.
• The study prioritized the usability of the visual function testing battery over task performance.
• The developed battery of five subtasks is validated and prepared for clinical application in neurological patients.