51

The acquisition of reading and writing, or “literacy,” is probably one of the most powerful tools that we acquire in our lives and that transform our brain and cognitive system. In this article, we examine the fact that, beyond allowing the acquisition of new knowledge (through reading) and the external storage of information (through handwritten notes, books, computers, and so on), literacy induces three main changes in the brain networks dedicated to language. Indeed, literacy acquisition not only allows spoken language areas to be activated by written inputs, but also modifies the spoken language system itself through two mechanisms. On the one hand, literacy improves phonological coding (in the planum temporale) and, on the other hand, it makes, in some listening situations, orthographic representations be activated top-down by spoken inputs (in the left occipitotemporal cortex). In addition, literacy induces anatomical changes, including in intra- and inter-hemispheric connectivity. Lastly, we highlight the theoretical and practical implications of these findings for neuropsychologists.