Check out the current issue of Scientific American Mind -- on newsstands now! -- to see an "Ask The Brains" feature co-authored by Greg Hickok and Carol Padden on the topic of whether deaf people talk to themselves in sign language. Short answer: Of course they do! For a slightly longer answer you can view the article itself for the ridiculously low price of only $4.95. Act now and you not only get the Ask The Brains piece, but you will also receive attractive mug shots of Dr. Padden and yours truly. But wait, there's more! The good folks at SciAm will throw in the entire Oct/Nov issue for that low, low price, which includes what looks to be an interesting article by Eric Kandel, among others.
Seriously though, the question of whether deaf people talk to themselves connects with a burgeoning literature on the nature of neural/cognitive representations of "inner sign" vs. "inner speech" which, of course, if typically studied under the guise of linguistic (verbal) working memory. I say "under the guise" because our own view (see Hickok & Poeppel, 2000/2004 & Hickok et al. 2003) is that verbal working memory is not its own encapsulated cognitive system, but instead falls out of the operations of the dorsal-stream auditory-motor integration circuit that we have been promoting for several years now. The relevance of sign language to the question of neural representations of such inner linguistic abilities (whether we call them verbal working memory or sensory-motor integration) should be obvious: it allows us to assess whether the representations involved are tied to specific sensory-motor modalities, or whether they involve more abstract amodal processes. Short answer to this question: a little bit of both. More on this in future blog entries.
Btw, if YOU have a brain/language question you'd like answered, send us an email with the heading "Ask the Talking Brains." If the question is halfway coherent and/or we can think of something halfway coherent to say about it, we'll post your question and our response in a blog entry. :-)
Hickok, G., Buchsbaum, B., Humphries, C., & Muftuler, T. (2003). Auditory-motor interaction revealed by fMRI: Speech, music, and working memory in area Spt. Journal of Cognitive Neuroscience, 15, 673-682
Hickok, G. & Poeppel, D. (2000). Towards a functional neuroanatomy of speech perception. Trends in Cognitive Sciences, 4, 131-138
Hickok, G. & Poeppel, D. (2004). Dorsal and ventral streams: A framework for understanding aspects of the functional anatomy of language. Cognition, 92, 67-99.