Authors:

GRAHAM, N.L., PATTERSON, K. & HODGES, J.R.

Reference:

Year of publication:

2001

CBU number:

5296

Abstract:

Objectives: To document and analyse the emergence of jargon dysgraphia, at approximately 5 years into disease progression, in a patient initially presenting with left-temporal atrophy, severe anomia, mild semantic impairment, surface dyslexia and surface dysgraphia. Methods: The principal experimental procedure involved serial administration of tests of written and oral spelling to dictation, with the goal of specifying (a) the similarity between target word and response in terms of length and overlapping letters, and (b) the orthographic legality and letter frequencies of the spelling responses. Results: After FM ceased to spell any words correctly, or even in a phonologically plausible manner, her spelling responses maintained greater than chance overlap with dictated target words in length and constituent letters. The gap between targets and responses gradually widened, however, until her responses consisted of apparently random strings of letters that were nonetheless word-like, well-formed and fluently executed. FM's speech became ever more anomic, empty and stereotyped, but never revealed a hint of jargon aphasia. Conclusions: The rarity of violations of graphotactic rules, in conjunction with a significant effect of letter frequency, demonstrates that even when almost totally unconstrained by information from the target word, FM's spelling responses were influenced by premorbid spelling knowledge. Discussion will focus on whether this jargon dysgraphia, a spelling disorder not previously reported in the context of degenerative disease, is best explained by weak activation of orthographic representations or by isolation of the orthographic system from semantics and phonology.