Abstract: Many studies have revealed the cognitive ability of illiteracy who had not receive normal school education. Originally, the studies of illiteracy concentrated on spoken processing and phonological awareness.Then, those studies of illiteracy investigated phonological and semantic processing of words. With the development of brain imaging techniques, many researchers focused on the illiteracy’ cognitive mechanism of word processing and how the early spelling ability modulated the organization of brain function. These researches discussed the function of the left fusiform gyrus in the word recognition and the laterality of brain function of illiteracy. In the future the studies of how the brain change with the illiteracy learning spelling and how the influence of cultural cognition to aging are interesting.

Key words: illiteracy, word processing, cognition, brain function