Vygotsky's analysis of the changes in our thinking that take place as we move from early spoken language to develop literacy is one of the major discoveries of the twentieth century. It is set out in Thought and Language, Chapter 6 (MIT Press, any edition). Vygotsky's categories were "inner speech" - the language that is inside our heads all the time, whether or not we are communicating with other people - "speech", and "written speech", which, he said, required "deliberate structuring of the web of meaning".
The introduction to writing in the British National Curriculum for languages involves copying out words, an activity which forces children to jerk their eyes back and forth between the original and their own version, concentrating on remembering sequences of letters rather than constructing meaning. The alternative is Clicker, www.cricksoft.com, a piece of software that allows children to build sentences from words the teacher presents to them at the foot of a computer screen. All their attention is focused on selecting the words they need, and you can include grammatical inflections and variations as well as basic vocabulary. A speech engine, optional extra, will read the sentences back with realistic accentuation. Using Clicker, I regularly enable young children to construct sentences in foreign languages, then hold them in their minds and write them without copying. Commercial product though it is, it is the most useful bridge between written and spoken language I have ever seen. It works with non-Roman scripts - you can insert Chinese characters as pictures, and reverse the word order to read from right to left. For more detail, follow this link:
www.cricksoft.com/uk/ideas/johnbald.htm