Navigating without Vision: Basic and Applied Research

JACK M. LOOMIS, ROBERTA L. KLATZKY, and REGINALD G. GOLLEDGE
2001 Optometry and Vision Science  
We describe some of the results of our program of basic and applied research on navigating without vision. One basic research topic that we have studied extensively is path integration, a form of navigation in which perceived self-motion i s integrated over time to obtain an estimate of current posilion and orientation. In experiments on pathway completion, one test of path integration ability, we have found that subjects who are passively guided over the outbound path without vision exhibit
more » ... nificant errors when attempting to return to the origin but are nevertheless sensitive to turns and segment lengths in the stimulus path. We have also found no major differences in path inlegration ability among blirid and sighted populations. A model we havc developed that attributes errors in path integration to errors in encoding the stimulus path is a good beginning toward understanding path integration performance. In otber research on path integration, in which optic flow information was manipulated in addition to the proprioceptive and vestibular information of nonvisual locomotion, we havc found that optic flow is a weak input to the path integration process. In other basic research, our studies of auditory distance perception in outdoor environments show systematic underestimation o C sound source distance. Our applied research has been concerned with developing and evaluating a navigation system for the visually impaired that uses three recent technologies: the Global Positioning System, Geographic Information Systems, and virtual acouslics. Our work shows that there is considerable promise of these three technologies in allowing visually impaired individuals to navigate and learn about unfamiliar environments without the assistance of human guides. (Optoni Vis Sci 2001;78:282-289) Key Words: u r l i t o r y c1ist;lrice perception, hlincl, GIs, Geographic: Iriiorrnatiori System, GPS, Global Positioning Sys1rri1, r~,~~i g a~i o n , navigalion syslsrn for t h e blirid, path i n t c g r~l i o n , spatiat hearing, virtu;ll sound, visually inip=~irt.cl Jack M . Loornip D q a r m m t of Psychology
doi:10.1097/00006324-200105000-00011 pmid:11384005 fatcat:hy3hctrqjbedzgtkxllulqtjwq