Visual Experience and Access to Spatial Knowledge

Persons who were congenitally blind, late blind, and blindfold sighted learned an object-array by being guided within it in cardinal directions towards walls. Subjects then judged the near, far, left, and right locations of objects from different points of observation (PO). One-half of the subjects were guided to POs and at spot informed about their orientation (actual condition). The rest were first asked to imagine being at POs (imaginal condition). Group and task condition did not interact, but group and PO did: Visual experience speeded up judgments, especially in corners. The sequence imaginal-actual speeded up judgments in all groups.