Have you ever ridden a roller coaster and felt nauseous, or off balance as you walk off the ride? Motion sickness experienced on an amusement ride has very similar symptoms to cybersickness. Cybersickness or virtual reality sickness is a real phenomenon that can result in lingering aftereffects that impact your balance and motor skills even hours after the experience.
Inexpensive virtual reality head mounted displays (e.g., Gear VR, HTC Vive, Oculus Rift, PlayStation VR) have been available to content developers for a while now to create gaming experiences or training content for military, industrial or sports market verticals. Even less expensive systems are beginning to proliferate in the consumer market (e.g., Google Cardboard, Google’s Daydream, View-Master VR) with the potential to change the way we consume entertainment content daily. Microsoft’s HoloLens, an augmented reality system, promises to change the way we work by putting the equivalent of your notebook computer on your head and allowing you to work with email, Skype, your internet browser or other applications virtually.
The future of work is going to be altered by this technology. Lack of awareness of the impact of cybersickness or even the strain these systems can put on your visual system could negatively impact productivity, safety and satisfaction.
Design Interactive’s President and Founder Dr. Kay Stanney is the leading expert in cybersickness and answers a few questions about why it occurs and how you can combat it.
Does cybersickness really exist?
The problems associated with virtual reality (VR) technology are real and are typically coined “cybersickness.” Peruse any number of VR blogs today and you will find cybersickness is alive and making people feel not so well! It is a real threat to the widespread adoption of VR applications.
So, then what exactly is cybersickness, and why does it happen?
Cybersickness occurs because of the disconnect between what our eyes are seeing and what our ears, or vestibular system, is telling us. It is similar to the nauseous feeling that occurs when you get seasick. When you experience seasickness the eyes tell you that you are stationary, but your inner ears tell you otherwise. Contrary, in cybersickness your eyes see movement, yet you aren’t actually in motion. This imbalance is what causes the queasy feeling. VR exposure can cause people to vomit (about 1%), experience nausea (about 70%), disorientation (about 70%), and oculomotor problems (about 80%). It can also cause sleepiness (a.k.a. sopite syndrome; about 40%) and visual flashbacks (about 10%). Approximately 80% to 95% of those exposed to a VAMR [Virtual, Augmented and Mixed Reality] experience report some level of symptomatology post-exposure, which may be as minor as a headache or as severe as vomiting or intense vertigo.
Are there any effects from this digitally induced sickness that are long lasting?
Yes; perhaps even more troubling than the sickness symptoms, the problems do not stop immediately upon cessation of exposure. In fact, VAMR exposure is associated with aftereffects, which can render the exposed individual ill-equipped to operate in their normal environment for a period of time after exposure. These aftereffects can manifest as postural instability, visual displacements (e.g., altered vestibulo-ocular reflex), and altered hand-eye coordination, among other ailments. Strictly speaking, any effect of a VAMR that persists after an individual has returned to the real world qualifies as an aftereffect. These aftereffects generally result from an individual’s adaptation to the VAMR, which is the natural and automatic response to an intersensorily imperfect VAmR (sensory conflicts) and is elicited due to the plasticity of human sensory systems. The concern here is particularly with protracted exposure, which is ever more possible with consumer off-the-shelf VAMR headsets, as the consequences may go beyond nausea to mirror the same kind of impairments associated with being inebriated – the inability to walk straight, touch your nose, and see clearly. Yes, indeed one day you may be pulled over for being VAMR drunk! In the past, we have even equated VAMR exposure to blood alcohol level.
How can cybersickness be combatted?
Cybersickness can be combatted with design and usage techniques. From a design perspective, you can minimize sensory conflicts, for example by adding concordant motion (e.g., a motion base to reduce visual-vestibular conflicts), asking observers to actively align their head/body to the behavior of the virtual motion they are experiencing, or when conflicts persist, providing some visual motion cues that match the vestibular system (e.g., adding stable visual cues, such as a fixed-horizon or a stable vehicle dashboard) or depth of field blur (which alleviates accommodation–vergence conflicts by masking high-frequency spatial data), peripheral blur, or dynamic field of view (e.g., modifying FOV based on speed and angular velocity). Similarly, you can provide rest frame cues (preferably visual background cues like a fixed-horizon, but alternatively smaller, subtle foreground cues such as HUD-type fixed arrows or grid lines, or even more pronounced stationary visual cues [e.g., researchers at Purdue found a virtual nose to be somewhat effective]) that are consistent with an observer’s vestibular cues. You can also design to support adaptation to the novel motion dynamics through repeat exposures, active viewpoint control (e.g., be the driver not the passenger), or through the provision of visual “leading indicators” (e.g., visual arrows highlighting direction of travel to support movement predictability) or physical leading indicators (e.g., linkage of a passive observer’s hands to an active observer’s control handle to passively receive indications of forthcoming motion) that allow passive observers to reliably predict how the viewpoint is going to change. From a usage perspective, you can keep exposure durations short and take breaks to facilitate decompression from exposure.
Who should be concerned about it?
Cybersickness is a concern for technologists, VAMR application developers, and users alike. From a technology perspective, gains are being made to eliminate shortcomings that lead to cybersickness, such as latency, jitter, flicker, and calibration issues. Application developers are defining design techniques that minimize cybersickness, such as adding motion bases, using creative movement techniques, and providing visual rest frames. Users need to be cognizant of the adverse effects of VAMR exposure so they can self-monitor for sickness and deleterious aftereffects (e.g., ataxia, visual disturbances, and coordination issues) and adjust their exposure duration accordingly.
What do we still not know?
While many have postulated its causes, we still have no definitive theory of cybersickness. Most studies have been done with young adults, so we know little about the impact of VAMR exposure on children and older people. We also are just starting to develop a set of VAMR design principles that can optimize the user experience while minimizing cybersickness.
How can we mitigate these effects from interfering with our daily lives outside of the virtual reality?
In my opinion, if VAMR are designed to minimize the adverse effects of exposure and the user is prudent, keeping exposure duration short and taking breaks, then these tactics can help mitigate the problems. However, until we are able to safely mimic the missing vestibular cues in visually-based VAMR environments and create optics that don’t pose an undue burden on the visual system, the problems are likely to persist.
How is Design Interactive positioned to be the leaders in understanding and mitigating cybersickness?
Design Interactive is leading the way in developing best practices and design specifications for low cost VAMR solutions that minimize adverse effects. We are working with content developers in industries such as military training and entertainment/amusement to ensure the content created avoids common mistakes that lead to cybersickness while still permitting a positive and engaging experience for end users. DI has also developed objective measures of the physiological impact of VAMR technology both during and after exposure to help our clients design content that is more readily tolerated. We will soon be introducing an algorithm that can predict the onset of cybersickness and be used to evaluate content, create break schedules and improve the state of existing VAMR training systems and amusement attractions, thereby helping VAMR developers overcome this nettlesome problem.