Virtual reality is mostly used in movies and gaming system. In 2014, Mark Zuckerberg, Facebook CEO, spent $2 billion to get Oculus VR and its Rift virtual-reality headsets. In addition, Google vends a boxy cardboard viewer that enables to turn smartphones screen into VR wonderlands for only $15. You Tube has introduced live, 360-degree video.
There is a barrier to the extensive use of this technology because Virtual reality sometimes makes people sick.
Virtual-reality sickness is not a new phenomenon. It has been detected in test pilots, potential astronauts and test drivers while they test their skills, although it has been referred simulator sickness in these cases. Unlike seasickness or motion sickness, virtual reality sickness has its origin in the disparity between the vestibular systems and visual, states Jorge Serrador, an expert in pharmacology, physiology and neuroscience.
But how does VR sickness work? Imagine you are standing below deck in vessel on choppy seas. Assume the whole cabin is moving, therefore, your eyes tell you are standing still. But you can feel the motion — down, pitching side to side and up. You begin to feel clammy and have headaches. You can also go pale and start looking for a trash basket to retch.
The problem begins in the vestibular system in the inner ear. The system consists of three semicircular canals that have hair cells, so referred for their hair-like projections into a series of fluid filled chambers and canals. As the head moves, the fluid in the canals moves, which result to stimulation of the hair cells. Since each canal is located differently, each relays information on a different kind of movement to the brain: down/up and side to side.
Semicircular canal is connected to the utricle, a sac comprising of tiny carbonate particles known as otoliths and fluid. If the head is in motion, the otoliths move too, relaying the brain signals of horizontal movement. Next there is a chamber known as saccule that uses a similar setup to perceive vertical acceleration.
This system works in tandem with the proprioceptive system and the virtual system, integrating sensations and sight from joints and muscles to tell the brain the location of the body. A virtual-reality puts a wedge between these systems.
Virtual-reality sickness, unlike car sickness and seasickness, it does not need movement at all. The problem was first reported in 1957 among helicopter-trainees. On 1989, the study revealed that many military pilots sickness during simulator training.
In response to simulator sickness, simulator developers began adding motion to their models, forming plane simulators that pitched, moved up and down and rolled a bit. But sickness still did not stop because the simulator motion and the computer visualization might not line up fully.
As the mismatch become bigger, the sickness becomes worse. A study conducted in 2003 and published in the journal Neuroscience Letters, researchers in Japanese got people in a VR simulator and asked them to move and turn their heads. Sometimes, the virtual-reality screen would twist and turn twice as much as the actual movement of a person. People in those condition said that they felt sicker compared to those in conditions where the visual cues and the movement matched up.
There is no who knows why visual and vestibular mismatches lead to nausea feelings. One theory suggests that takes the confusions ingestion of something toxic. It reacts by throwing up. However, this theory does not have enough evidence.
VR developers are working to reduce the nauseating effects of their products. For instance Oculus Rift came up with a soaped-up refresh rate that prevents visual lags as you navigate the virtual world.