Editing Spatial disorientation (section)

== Physiology ==
There are four physiologic systems that interact to allow humans to orient themselves in space. Vision is the dominant sense for orientation, but the vestibular system, proprioceptive system and auditory system also play a role.{{cn|date=June 2022}}

Spatial orientation (the inverse being spatial disorientation, aka ''spatial-D'') is the ability to maintain body orientation and posture in relation to the surrounding environment (physical space) at rest and during motion. Humans have evolved to maintain spatial orientation on the ground. Good spatial orientation on the ground relies on the use of visual, auditory, vestibular, and proprioceptive sensory information. Changes in linear acceleration, angular acceleration, and gravity are detected by the vestibular system and the proprioceptive receptors, and then compared in the brain with visual information.{{cn|date=June 2022}}

The three-dimensional environment of flight is unfamiliar to the human body, creating sensory conflicts and illusions that make spatial orientation difficult and sometimes impossible to achieve. The result of these various visual and nonvisual illusions is spatial disorientation.<ref>{{cite book |last1=Previc |first1=Fred H. |last2=Ercoline |first2=William R. |date=2004 |title=Spatial disorientation in aviation |location=Reston, Virginia |publisher=American Institute of Astronautics and Aeronautics |isbn=978-1-60086-670-8 |doi=10.2514/4.866708}}</ref><ref name=Jedick/><ref>{{cite web|url=http://www.britannica.com/EBchecked/topic/558427/spatial-disorientation|title=Spatial disorientation - physiology |website=Britannica |access-date=30 July 2016}}</ref> Various models have been developed to yield quantitative predictions of disorientation associated with known aircraft accelerations.<ref>{{cite conference |last1=Newman |first1=Michael C. |last2=Lawson |first2=Ben D. |last3=Rupert |first3=Angus H. |last4=McGrath |first4=Braden J. |title=AIAA Modeling and Simulation Technologies Conference |date=August 13–16, 2012 |chapter=The role of perceptual modeling in the understanding of spatial disorientation during flight and ground-based simulator training |conference=AIAA modeling and simulation technologies conference |location=Minneapolis, Minnesota |doi=10.2514/6.2012-5009 |publisher=American Institute of Aeronautics and Astronautics|isbn=978-1-62410-183-0 }}</ref>