Coding disability : a pure dysgraphia

Abstract

In the present investigation, an attempt was made to identify a learning disability defined by a characteristic pattern of inconsistencies between written and oral school performance. Children with at least average verbal skills were described as being unable to produce coherent, detailed written passages, and their WISC-R Coding scores were depressed significantly in comparison to their other subtest scores. Labelled as Coding Disability (CD), the disorder was postulated to be a form of apraxic dysgraphia occurring in the absence of verbal/linguistic deficits. Twelve children whose Coding scores were at least 3 points lower than their Vocabulary scores were selected for the Coding Disabled group. They were matched on age and sex with children who showed minimal subtest scatter. The Similarities, Vocabulary, Block Design, and Coding subtests, the Peabody Picture Vocabulary Test, and a modified version of the Gates-MacGinitie reading comprehension test were administered to both groups. Because the Coding Disability was postulated to be neurologically mediated and independent of external influences, measurements were repeated under low and high motivation. It was predicted that, under high motivation, the CD children would improve significantly on all scores except Coding and Written recall. The Control children were expected to improve on all scores. This hypothesis was confirmed; change scores differentiated the two groups only on the Coding and Written recall tests. The findings point to the existence of a group of children whose poor writing skills are hardwired and impervious to motivational influences.