DISORDERS OF SPELLING

Limited retention of information in the graphemic buffer

This study examined a patient who mainly made letter deletion errors in spelling. It was hypothesized that his errors were due primarily to limited ability to retain information in the graphemic buffer, a structure that holds sequences of abstract letter identities for output. Consistent with this hypothesis, the patient's spelling accuracy declined on long words, but the number of letters he wrote per response was not related to word length. Moreover, by having him write words forward and backward, it was shown that his accuracy within a word depended on which part of the word he tried to output first. These results also ruled out alternative accounts of the patient's spelling deficit based on neglect or damage to lexical representations.

Childhood dysgraphia. Part 1. An illustrated clinical classification

In this paper we propose a clinical neurological classification of childhood dysgraphia (medical model). The subject is introduced by briefly considering the childhood learning disorders as a whole, and subsequently dysgraphia will be considered in particular with description and illustration of the different types. In our second paper we report a detailed neuropsychological study which we made of 66 children with dysgraphia. In view of the differing definitions used between professionals, this first paper is an attempt to define the terms used in our classification so that subsequent statistical analysis of individual factors in aetiology and neurology can be interpreted.

The neuropsychology of writing and spelling: semantic, phonological, motor, and perceptual processes

Neuropsychological data is reviewed in order to delineate the semantic, phonological, motor, and perceptual processes underlying spelling, with particular attention to handwriting. These data support a model in which semantic, lexical phonological, and non-lexical phonological processes can generate spelling, either independently or in an interactive fashion. Oral and written spelling depend upon common processes up to, and including, an orthographic code. After this point they each depend upon several separate stages of information processing.