Vection and simulator sickness.
Simulator sickness has been identified as a form of motion sickness in which users of simulators exhibit symptoms characteristic of true motion sickness.  In a fixed-base simulator, visual and vestibular sources of information specifying dynamic orientation are in conflict to the extent that the optical flow pattern viewed by the pilot creates a compelling illusion of self-motion, which is not corroborated by the inertial forces transmitted through the vestibular sense organs.  Visually induced illusory self-motion is known as vection, and a strict interpretation of sensory conflict theory of motion sickness suggests that vection in a fixed-base simulator would be a necessary precondition for simulator sickness.  Direct confirmation of this relation is reported in this article.
Hettinger
L J
LJ
Essex Corporation.
Berbaum
K S
KS
Kennedy
R S
RS
Dunlap
W P
WP
Nolan
M D
MD
D000293:Adolescent; D000328:Adult; D000337:Aerospace Medicine; D001359:Aviation / Q000193:education*; D006801:Humans; D008297:Male; D009041:Motion Sickness / Q000209:etiology* / Q000523:psychology*; D009903:Optical Illusions; D011434:Proprioception; D011795:Surveys and Questionnaires