Emmorey, K. & Corina, D. (1993). Hemispheric specialization for ASL signs and English words: Differences between imageable and abstract forms. Neuropsychologia, 31(7), 645 - 654.
American Sign Language (ASL) exhibits properties for which both hemispheres in hearing people show specialized functioning (linguistic vs. spatial). To determine the laterality of processing ASL in the normal intact brain, ASL signs and nonsigns were presented to each visual half field of deaf signers for lexical decision. The English glosses for these signs were presented to hearing English speakers along with nonwords. Deaf ASL signers and hearing English speakers both showed a left hemisphere advantage for abstract lexical items. ASL signers showed a significant right hemisphere advantage for imageable signs, whereas English speakers exhibited no visual field effect for imageable words. This difference in brain laterality may reflect differences in the role of imagery in the two languages.