The specificity of notation codes in apraxic agraphia: dissociation between Arabic and alphabetical scripts in a...

This article describes the case of a patient with corticobasal syndrome, who showed severe ideomotor and visuoconstructional apraxia along with handwriting difficulties more marked for letters and words than for digits and numbers. For alphabetical script, these difficulties were less marked when graphic motor patterns were activated with a model, whilst for digits IV's graphic productions were better in dictation. Moreover, IV's graphic production was negatively influenced by graphomotor complexity for letters but not for numbers. IV is the first reported case of a patient with severe limb apraxia, who also showed peripheral agraphia, with dissociation in alphabetical and numerical notation codes resulting from a specific deficit in the activation of graphomotor programs.