ABSTRACT
Though vision is of great importance in keeping track of where one is when moving through the environment, we nevertheless seem to be able to successfully update our positions relative to surrounding objects and surfaces when walking without vision (Thomson, 1983). Two distinct types of mechanism have been proposed to underlie this ability:
A computational process that calculates the distance and direction walked on the basis of non-visual sensory cues, and then combines the result with a memory representation of the environment in order to work out one’s new location. A model of this type has been proposed by Book and Gârling (1981).
A direct and automatic updating process. Locomotion generates not only optical flow, but also proprioceptive information, and these two sources of information are strictly correlated. Rieser, Guth, and Hill (1986) proposed that individuals become attuned to the association between vision and proprioception so that proprioception alone produces immediate and non-inferential awareness of one’s change of position, just as vision does. Updating one’s position can therefore be accomplished on the basis of proprioceptive information when vision is not available.
