Visuo-spatial imagery in congenitally totally blind people.

The present study provides evidence for congenitally blind people's ability to generate visuo-spatial images, and explores its limitations. Congenitally blind and sighted participants were asked to memorize the spatial positions of target objects (cubes) in two- and three-dimensional matrices, while simultaneously performing a sequence of spatially based imagery operations. Furthermore, during half of the trials, subjects were required to perform an articulatory suppression task. Although articulatory suppression affected both groups to the same extent, congenitally blind people performed poorly with more demanding spatial tasks and when an active elaboration was required.