Active control of locomotion facilitates nonvisual navigation

In some navigation tasks, participants are more accurate if they view the e nvironment beforehand. To characterize the benefits associated with visual previews, 32 blindfolded participants were guided along simple paths and as ked to walk unassisted to a specified destination (e.g., the origin). Paths were completed without vision, with or without a visual preview of the env ironment. Previews did not necessarily improve nonvisual navigation. When p reviewed landmarks stood near the origin or at off-path locations, they pro vided little benefit; by contrast, when they specified intermediate destina tions (thereby increasing the degree of active control), performance was gr eatly enhanced. The results suggest that the benefit of a visual preview st ems from the information it supplies for actively controlled locomotion. Ac curacy in reaching the final destination, however, is strongly contingent u pon the destination's location during the preview.