The neural representation of language in users of American Sign Language

Studies of American Sign Language (ASL) offer unique insights into the fundamental properties of human language. Neurolinguistic studies explore the effects of left and right hemisphere lesions on the production and comprehension of signed language. Following damage to the left hemisphere perisylvian regions, signers, like users of spoken languages, exhibit frank aphasic disturbances. Sign language paraphasia illustrates the linguistic specificity of impairment. A case study involving cortical stimulation mapping (CSM) in a deaf signer provides evidence for the specialization of Broca's area in sign language production. The effects of right hemisphere damage highlight the specialized properties of sign language use. Data from functional magnetic resonance imaging (fMRI) of deaf signers confirm the importance of left hemisphere language structures in the use of signed language, but also reveal the contributions of right hemisphere regions to the processing of ASL. These studies provide new insights into the complementary roles of biology and environment in language representation in the human brain. Learning Outcomes: As a result of this activity, the participant will read studies of aphasia in users of signed language and a discussion of neurolinguistic studies of paraphasia in ASL. The participant will examine the role of the right hemisphere in language use and findings from a functional imaging study of sentence processing in ASL and English. (C) 2001 Elsevier Science Inc. All rights reserved.