Brain specialization for language does not depend on literacy.
Aphasia in focal brain-damaged illiterates is analogous to aphasia in patients who have learned how to read and write, regarding (1) expectancy rate, (2) distribution of clinical types, (3) semiological structure, and (4) score of relevant laboratory variables. The organization of neurological structures whose lesions produce language disturbances seems to be independent from the acquisition of reading and writing skills.
Adult↗