In summary, if Broca in the left brain is injured or damaged, ASL speakers would have difficulty with expression as found in spoken language lesion. Likewise, if Wernicke in the left brain is injured, they would have difficulty with reception, similarly found in spoken language lesion.
As for activation in the right brain, it's related to visual-spatial processing. If there is lesion in the right brain in ASL speakers, they would have difficulty with using spatial relation (e.g. describing a room), but, they would still be able to describe a room using ASL words (e.g. "next to", "on top of", etc.) rather than using space.
Emmorey, Karen (2002). "Sign Language and Brain" Language, Cognition, and the Brain: Insights From Sign Language Reserach. Chapter 9, pp 271-314.
Harlan Lane, Robert Hoffmeister, Ben Bahan (1996). "Signed Language and the Brain". A Journey into the Deaf-World. pp 101-104.
Pickell, H., Klima, E., Love, T., Kritchevsky, M., Bellugi, U. & Hickok, G. (2007). "Sign language aphasia following right hemisphere damage in a left-hander: A case of reversed cerebral dominance in a deaf signer?" Neuroscase, 11, pp 194-203.
Saito, K., Otsuki, M., & Ueno, S. (2007). "Sign language aphasia due to left occipital lesion in a deaf signer." Neurology, 69, pp 1466-1468.
Related topic: Brain and (Sign) Language
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