What is the link between visual field and motion sickness?

Motion sickness occurs when there is a sensory conflict between visual input and vestibular messages: the eye perceives movement that the semicircular canals do not confirm, or vice versa. The width of the visual field, which refers to the portion of the scene that stimulates the peripheral retina, directly modulates the intensity of this conflict, and thus the likelihood of nausea, sweating, and dizziness.

Narrow field: the paradox of VR headsets

Conventional virtual reality headsets only offer a field of 30 to 60°; peripheral vision, specialized in speed detection, is deprived of optical flow while the head moves.

This 'sensory gap' creates a mismatch between actual vestibular acceleration and the absence of visual scrolling, promoting cybersickness: headaches, nausea, and dizziness. The problem worsens if the display lags: the scene moves across the retina while the vestibule has already registered the end of the movement.

Wide field: more stable immersion

Wide Field-of-View (180 × 95°) systems, such as CAVE or BNAVE devices, allow the periphery to capture optical flow consistent with vestibular accelerations.

In healthy subjects, these configurations significantly reduce the incidence and severity of simulator sickness compared to narrow HMDs. The brain finds lateral visual signals compatible with what the inner ear feels; the sensory-motor conflict resolves.

Too much moving periphery: reversed conflict

Conversely, projecting a rotating peripheral backdrop around a stationary subject induces the illusion of movement; the brain believes it is moving, while the vestibule remains silent.

This over-stimulation of vision causes nausea, cold sweats, and disorientation after a few minutes. The same mechanism explains car motion sickness: when seated in the back, one primarily sees rapid lateral scrolling (strong peripheral flow) without perceiving the actual acceleration of the road.

Prevention strategies

• VR: widening the FOV or displaying a fixed cockpit reduces conflict; lowering display latency is crucial.
• Transport: looking at the road (consistent central flow) or limiting peripheral vision (partially closing the eyelids) mitigates motion sickness.
• Vestibular rehabilitation: gradually increasing the magnitude and speed of peripheral flow (optokinetic) to acclimate sensitive patients to visually rich environments.

In summary

The more the peripheral visual field receives optical flow inconsistent with vestibular information, the more likely motion sickness is; too little periphery (narrow headset) or too much artificially moving periphery (rapid optokinetic stimulus) each create their own conflict. Therefore, adjusting the viewing angle and the coherence of the backdrop is an essential lever for preventing or treating motion sickness, both real and virtual.

References

1. Herdman S. J. & Clendaniel R. A. (eds). Vestibular Rehabilitation (4th ed.). F.A. Davis, 2014. - Chap. 28: "The Role of Emerging Technologies in Vestibular Rehabilitation" (Wide Field-of-View, HMD & cybersickness). - Chap. 6: "Postural Abnormalities in Vestibular Disorders" (Virtual Reality Environments).
2. Leigh R. J. & Zee D. S. (2015). The Neurology of Eye Movements (3rd ed.). Oxford University Press. Section "Optokinetic Stimulation and Circularvection".