Virtual Reality & Cybersickness

• Introduction

• Cybersickness symptoms

• Theories for the cause of cybersickness

• Physical pathologies

• Cybersickness effects

• Preventive solutions

• References

Introduction

• Definition• Cybersickness has been described as a

variant form of common motion sickness which has adverse effects upon the visual, neural, and psychological status.

Introduction

• Importance• Industrial needs and economic reasons

• Problems in research• Difficult to predict who will be adversely

affected • No government regulations

Cybersickness symptoms

• Disruption to perceptual and sensory-motor activities involving the vestibular system

• Disorientation

• Disequilibrium

• Inappropriate vestibular-ocular reflex

• Autonomic response• Drowsiness, Salivation, Sweating, and Vomiting

• Signs (HR, BP , RR , hypothermia)

Theories for the cause of cybersickness

• Computational lag theory• Lag between computation and display,

incompatibility between the actual and expected visual input to NS

• Vestibular-ocular incompatibility theory or sensory conflict theory

• Difference between the ocular input and the vestibular input results in an nausea response by NS

Physical pathologies

• Repetitive stress injury• Extended use and repeated movements

(joystick or keyboard)• Functional disability (tendinitis and

ligamentous injury)

Physical pathologies

• Immersion injury• Any physical trauma occurring during VR

use• So involved and engrossed in VR,

Disoriented with their immediate surroundings

• Attempt unsafe action with wearing a device (running or jumping)

Physical pathologies

• Transmittable disease• Potential fomite to harbor pathogenic

organisms• Used by multiple individuals• Airborne pathogens and skin flora on HMD

or hand controllers• Streptococcus species, hemophilus

influenza, and multiple viruses

Cybersickness effects

• Visual effects– Nausea– Asthenopia (eyestrain)– Impact of electromagnetic fields (eyes)

Cybersickness effects

• Neural effects– Impact of EMF on CNS

• Cellular damage

– Flicker vertigo• Seizure while a flickering light is observed

• Brief loss of attention

• Occurs on flicker frequency of 8 to 12 Hz

Cybersickness effects

• Psychological effects– Develop a new personality in VR– Acrophobia or Claustrophobic– addicted– Residual aftereffects

• Illusory sensations of climbing and turning

• Perceived inversion of the visual field

Preventive solutions

– Keep exposure duration short until your senses are accustomed to VR

– Refrain from jerky or quick movements when first immersed

– Allow enough time to readaptation in real world before do anything risk

– Don’t sit down, active, interaction with new environment when readapted

Preventive solutions

• Warning label on VR for children• Avoid poorly designed HMDs• Learn to properly adjust lenses• Avoid prolonged or excessive use of VR

• Consult a physician if you experience prolonged dizziness or nausea

Preventive solutions

• Drug therapy– Reduce vestibular output– Control nausea and individual training– Adverse side-effects on performance and

reliability of the operator

References

• http://www.cs.cmu.edu/~dccrow/uwaterloo/KIN_416.html

• http://www.academic.marist.edu/papers/karin/virtual.html

• http://www.I-med.com/mi/safety.html• http://www.oir.ucf.edu/pubrel/reportarchives/UCF

Report03.08.96/cybersickness.html• http://ie.engr.ucf.edu/vr_research/synergy/sick.ht

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