Terry K, Sinitski EH, Wilken JM, Dingwell JB. 

XXIII^rd Conference of the International Society of Biomechanics, Brussels Belgium 2011.

Kinematic and temporospatial effects of medio-tareral mechanical and visual perturbation amplitudes during gait.

http://homepages.ulb.ac.be/~labo/ISB2011/ISB2011_ScientificProgram_files/558.pdf

This study examined how kinematic and temporo-spatial gait parameters change in response to multiple amplitudes of sinusoidal pseudo-random medio-lateral (M-L) visual and support surface (mechanical) perturbations in an immersive virtual reality (VR) environment. Our goal was to determine how perturbation magnitude altered gait variability. The variability of center of mass (COM) position, COM velocity, and step width in the M-L direction systematically increased with perturbation amplitude for the mechanical perturbations. However, larger visual perturbation amplitudes did not produce corresponding increases in any of these gait parameters.