Influence of step frequency on visual speed perception during locomotion

Abstract

[Thurrell et al. 1998] first observed that the perceived speed of optic flow decreases in linear proportion to the increasing physical speed of locomotion on a treadmill and proposed this as a mechanism to discount from the visual signal retinal motion due to self-motion, described as an arthrovisual effect [Thurrell and Pelah 2005]. Since human locomotion consists of a complex of articulated movement, step parameters and associated afferent, efferent and efference copy signals, questions arise as to the relative contributions of these component messages to the reduction in the perception of optic flow speed (POFS). Here we report experiments [Casey 2010] on the role of step frequency (SF) previously proposed as a reliable estimate for perception of the speed of self-motion [Durgin et al. 2007; Dong et al. 2008].