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Language, brain and disability

It has often been remarked that we come to appreciate unique complexity and function of language only when it starts to go wrong. This happens daily in many small ways - when we detect ambiguity, express ourselves incoherently, or speak at cross-purposes. Less commonly, it happens in dramatic and devastating manner, in form of language disability. Those who find it difficult or impossible to communicate, on account of some physical, psychological, or other disability, face frustrating, isolated, and uncertain future, in which their disability is often not recognized, and community support services may be inaccessible or absent. Drawing attention to existence and extent of language disability is thus important role for any encyclopedia of language.

(Adapted from: The Cambridge Encyclopedia of language)