ABSTRACT
In this chapter, brain organization of writing and writing disturbances associated with brain pathology will be examined. Initially, it will be proposed that historically writing developed in three different stages, and it is based in three different abilities: visuoconstructive, praxic, and linguistic. The analysis of writing disturbances observed in cases of brain pathology (agraphias) supports the assumption that there are three major types of agraphias corresponding to the impairment in each one of these fundamental abilities. Later in the section Brain Activation during Writing, contemporary neuroimagining studies are introduced and the patterns of brain activation observed during writing are reviewed. Different writing systems are currently used, and not only brain activation during writing but also clinical characterization of writing disturbances are not totally coincidental among these different writing systems; this question will be examined in the section On the Origins of Writing. Further, it will be emphasized that writing evolution has continued with the introduction of typewriters, and more recently, computers; brain control required for handwriting and for using computers is partially different; and it can be anticipated that toward the future new agraphia syndromes will be described. In the final section, some tentative conclusions are presented.
