3Chapter 3 Neural Organization of Language: Clues From Sign Language Aphasia
A central issue in understanding the neural organization of language is the extent to which this organization is dependent on the sensory and motor modalities through which language is perceived and produced. There are many reasons to think that the neural organization of language should be profoundly inuenced by extrinsic factors in development such as sensory and motor experience. The temporal processing demands imposed by the auditory system have been argued to favor left hemisphere systems (Tallal, Miller, & Fitch, 1993), which could, in turn, determine aspects of the lateralization pattern of auditory-mediated language. Superior temporal lobe regions thought to be important for language comprehension are situated in and around auditory cortices-a natural location given auditory sensory input of language. Likewise, Broca’s area, which is classically thought to play a role in speech production, is situated just anterior to motor cortex controlling the speech articulators. Thus, it would not be unreasonable to hypothesize that the neural organization of languageincluding its lateralization and within hemisphere organization-is determined in large part by the particular demands imposed by the sensory and motor interface systems.