ABSTRACT
The ability to use rule-governed language appears early in childhood and is present in every society of the world. This universality of language is carried by specialized brain structures that are revealed by losses in specific language functions that occur following damage to certain areas of the brain, and by corresponding patterns of metabolic activity in these areas when language tasks are performed by neurologically healthy adults (Goodglass & Wingfield, 1998). In cases where oral communication cannot be conducted, sign languages have developed that are equally as rich in lexicon and syntax but with manual movements used to express objects, actions, and their syntactic relations (Meier, 1991).
