Visual imagery and visual-spatial language: enhanced imagery abilities in deaf and hearing ASL signers.

The ability to generate visual mental images, to maintain them, and to rotate them was studied in deaf signers of American Sign Language (ASL), hearing signers who have deaf parents, and hearing non-signers. These abilities are hypothesized to be integral to the production and comprehension of ASL. Results indicate that both deaf and hearing ASL signers have an enhanced ability to generate relatively complex images and to detect mirror image reversals. In contrast, there were no group differences in ability to maintain information in images for brief periods or to imagine objects rotating. Signers' enhanced visual imagery abilities may be tied to specific linguistic requirements of ASL (referent visualization, topological classifiers, perspective shift, and reversals during sign perception).