ASL has been shown to result in:

1) Better visual spatial memory

Summary: Deaf and Hearing signers (ages 15-53) were better at remembering spatial locations for pictures of faces and shoes than Hearing nonsigners. In contrast, all groups were comparable at remembering spatial locations for nameable objects. This suggests that sign language experience improves organization and recall of visual spatial information that cannot be easily labeled.

2) Enhanced ability for visual imagery and mental rotations of visual objects.

Summary: Deaf and hearing native signers showed better ability to integrate fragmented visual pieces into whole figures than nonsigners. Signers were also better at mentally rotating objects than nonsigners.

3) Enhanced motion processing in the left language-dominant hemipshere

Summary: Deaf and hearing signers are faster than hearing nonsigners at detecting moving stimuli that appear in the right visual field. Researchers attribute the right visual advantage to ASL experience that is highly specialized in the left language-area hemisphere.

Arnold, P. and Mills, M. (2001). Memory for faces, shoes, and objects by deaf and hearing signers and hearing non-signers, Journal of Psycholinguistic Research,30, pp. 185–195.

Emmorey, K. and Bellugi, U. (1993). Visual imagery and visual–spatial language: enhanced imagery abilities in deaf and hearing ASL signers, Cognition,46, pp. 139–181.

Emmorey, K. and McCullough, S. (1998). Mental rotation within linguistic and non-linguistic domains in users of American sign language, Cognition,68, pp. 221–246.

Neville, H.J. and Lawson, D.S. (1987). Attention to central and peripheral visual space in a movement decision task. III. Separate effects of auditory deprivation and acquisition of a visual language, Brain Research, 405, pp. 284–294.

Bosworth, RG and Dobkins, KR (2002). Visual field asymmetries for motion processing in deaf and hearing signers, Brain and Cognition, 49, pp. 170–181.

Bavelier et al., (2001). Impact of early deafness and early exposure to sign language on the cerebral organization for motion processing, Journal of Neuroscience, 21, pp. 8931–8942.