Language processing in the human brain of literate and illiterate subjects

Using functional magnetic resonance imaging (fMRI) or positron emission tomography (PET), much knowledge has been gained in understanding how the brain is activated during controlled experiments of language tasks in educated healthy subjects and in uneducated healthy subjects. While previous studies have compared performance between alphabetic subjects, few data were about Chinese-speaking individuals. In alphabetic subjects, studies indicate that the literates surpass the illiterates, especially in tasks involving phonological processing, and that different activation regions in fMRI are located between Broca's area and the inferior parietal cortex, as well as the posterior-mid-insula bridge between Wernicke's and Broca's area. In Chinese subjects, the results were shown in silent word recognition tasks (the left inferior/middle frontal gyrus and bilateral superior temporal gyri) and in silent picture-naming tasks (the bilateral inferior/middle fontal gyri and left limbic cingulated gyrus). In this study, the authors use some recent fMRI data to investigate language processing in the human brain of literate and illiterate subjects.