Issues and Challenges

There is high level of concern over the negative influences of interactive VR environments towards social implications. The users who are engage in violence VR video games and television in the virtual world may become desensitized to their their violent virtual actions and mimic that behavior in real world. There are other issues like people turning their backs on the real world and wander around the synthetic worlds that fulfill their whims. As of now, violence in VR is nearly inevitable but it is still important to address social issues before they result in crisis or harm.

For a virtual environment systems to be compatible with their users, it is vital for designers to understand design constraints imposed by human sensory and motor physiology. The physiological and perceptual issues that directly impact the design of virtual environment systems are visual perception, auditory perception, and haptic and kinesthetic perception.
The human visual system is very sensitive to any anomalies in perceived imagery and becomes prominent when motion is introduced into a virtual reality. In auditory perception, there is challenge for audio localization to obtain realistic auditory environment. Localization is helps differentiating sound sources and their direction. In VR, localization is determined by intensity differences and temporal or phase differences between signals at the ears.
The mechanical contact with the skin is called a haptic sensation (touch). The sensations of the skin adapts with the exposure to a stimuli. The sensation decreases in sensitivity to a continued stimulus and may disappear completely in long run. It also varies on receptor type, whether to rapidly adapt and relate to pressure, touch and smell or not. Therefore, it is very important to incorporate haptic feedback in virtual environments. Whereas, Kinesthesia is an awareness of the movements and relative position of body parts and is determined by the rate and direction of movement of the limbs. The challenge of kinesthesia in VR include the fact that a small rate of movement of a joint can be too small for perception and certain kinesthetic effects are not well understood.

Ensuring Health and safety of users are important and challenging issues for VR systems to avoid discomfort, harm or even injury. Developers should ensure that advancement in technology do not come at the expense of human well-being. When experiencing VR, the brain tends to work harder to integrate the unusual stimuli being presented to the different senses. Therefore, VR has power to affect the senses and brain of a user, leading to fatigue or sickness such as dizziness and nausea unlike any other simpler media. It is due to the problems in hardware, low-level software or carelessness of a VR developer who disregards the side effects of the experience on the user. Prolonged repetitive VR movements can lead to fatigue as the interference requires large amounts of muscular effort.
VR users has high chances of affecting their tissues. The HMDs and other visual displays are closely coupled with eyes can harm user’s eyes by the electromagnetic field (emf) and laser lights from VR systems if the exposure is prolonged. Even the poor adjustments of HMD can cause eye strains and head, neck and spine could be harmed by the weight or position of HMDs. Imbalance of body position due to VR systems could make the user fall or trip resulting bumps and bruises.

Cyber Sickness : Cybersickness is a form of motion sickness that occurs as a result of exposure to VR. It can range from slight headache to an emetic response. Several factors has been identified that may contribute to cybersickness such as vection, lag, field of view but it is still an undergoing research to identify the specific causes of cybersickness and to develop methods to alleviate this ailment. Vection is illusion of self-movement in VR which causes conflicts between the visual and vestibular system in the body because the motion is just illusion. Lag occurs when a user perceives a delay between the time a physical motion is made and the time the computer responds with a corresponding change in the display because of spatial distortions and rearrangements using mirrors and prisms.
Other indirect consequences of VR exposure such as head spinning, postural ataxia, reduced eye-hand coordination, vestibular disturbances and etc.