The Organization of Language and the Brain

TLDR

Research on language organization in the brain relies on post‑mortem studies of patients with left‑hemisphere damage, leading to the identification of aphasias and the development of Wernicke’s localization theory. Wernicke’s localizations have withstood repeated testing and uniquely predict new phenomena, making his theory the sole model that accounts for novel observations.

Abstract

The study of the organization of the brain for language has been based of necessity on investigations in man. The bulk of our information in this area has come from careful studies of patients suffering from isolated damage as a result of vascular disease, whose brains have, after death, been subjected to careful anatomical examination. Disorders of language resulting from brain damage, almost always on the left side, are called aphasias. Carl Wernicke, nearly 100 years ago. described the linguistic differences between aphasias resulting from damage in different anatomical locations and outlined a theory of the organization of language in the brain. Not only have Wernicke’s localizations stood up under repeated examinations but his theory has been the only one which has permitted the prediction of new phenomena, or has been able to account for new observations. Several remarkable disorders, such as isolated disturbances of reading and the symptomatology of the corpus callosum, are examples of the explanatory power of this theory.