VESTIBULAR DISORDER / MOTION SICKNESS
Dizziness, vertigo and disequilibrium are commonly reported symptoms with different meanings and different diagnosis, making it difficult to get a correct diagnosis. While reports of unsteadiness, perception of movement, and imbalance may be caused by several vestibular disorders, these symptoms could also be attributed to the perceptual distortions experienced by individuals with visual stress.
Visual stress is caused by a sensitivity to light and patterned visual images in the environment and can lead to physical discomfort including nausea, dizziness, disequilibrium, and headache; and perceptual distortions including movement of text, appearance of lights or colours, and warping or change to stationary objects causing the sensation of movement or instability. These symptoms can lead to difficulties navigating the environment when there is a loss of equilibrium that is often accompanied by spatial disorientation. Patterned carpets may appear to move, tile floors may appear crooked, doorways or windows may appear to lean, or escalators appear to shimmer or vibrate.
Research into visual stress and its relationship to visually induced motion sickness noted that the strong sensory stimulation that leads to visual stress might be effective at evoking motion sickness as well. While visual stress and visually induced motion sickness are different conditions, they share the same mechanisms. 
It is important to include visual stress when investigating possible causes of symptoms and investigate individually prescribed coloured filter lenses as a means to relieve symptoms.