The relationship between treatment outcomes and the underlying cognitive deficit: Evidence from the remediation of acquired dysgraphia

Background: It is unclear to what extent treatment outcomes are significantly influenced by the specific cognitive deficits that underlie an individual's language impairment. That is, it is not well understood if treatment benefits such as item-specific relearning, generalisation to untreated items, and long-term maintenance vary according to deficit type. Aims: The aim of this investigation was to look at the relationship between deficit type and responsiveness to treatment by examining the results of applying the same remediation protocol to individuals suffering from deficits affecting different components of the spelling process. Methods & procedures: Three adults with acquired dysgraphia were identified as suffering from deficits to either the orthographic lexicon or the graphemic buffer. They were administered the same spell-study-pell treatment protocol during bi-weekly sessions for periods of 7-11 weeks with periodic follow-up evaluations that continued for 40-112 weeks after the end of treatment. Outcomes & results: All three individuals exhibited significant item-specific treatment benefits that were apparent even 40-112 weeks after the end of treatment. Furthermore, the individuals with the graphemic buffer deficits showed generalisation to untreated words, while the individual with the orthographic lexicon deficit showed an item-specific benefit merely from the repeated testing of words. Conclusions: The presence or absence of generalisation effects appears to be related to the nature of the underlying deficit, while the long-term stability of treatment benefits does not.