Do Specific Agraphias Exist?

Ten years of work on the acquired dyslexias has been basically positive as far as the broader cognitive neuropsychology research program is concerned. However, the overall picture is complicated as the use of the syndrome-complex approach and the large variety of syndromes and sub-syndromes that have been isolated have led to the natural lines of functional cleavage in the domain being not too clearly visible. As a counterpoint, it would be useful to take another domain where the correspondence between syndromes and normal function is simpler. The complementary set of disorders – the agraphias, impairments in the writing process – provides an excellent example in this respect.

Before 1980, agraphia was treated by neuropsychologists as a poor relation of aphasia. Writing was viewed as a highly complex secondary skill, with forms of breakdown of little theoretical interest. Most work was concerned with the pattern of the concomitant aphasic or apraxic disorders that occurred with agraphic difficulties (see, e.g., Marcie & Hécaen, 1979). One influential view was that cases of agraphia that appeared to be pure were not the result of damage to specific mechanisms concerned with writing, but were the secondary effect of a confusional state characterised by a reduction and/or ready shifting of attention (Chedru & Geschwind, 1972). Writing, it was argued, was affected because it is a complex skill that is rarely overlearned.