Lexicalization errors in writing arabic numerals: a single-case study.

This paper presents a single-case study of a patient suffering from several impairments in number processing. The main focus of the paper is to describe and interpret the patient's errors in verbal to arabic transcoding. The errors were of the syntactical type and consisted of partial lexicalizations appearing mainly in response to items with Thousand in sum relationships and less frequently with Hundred in sum relationships. The Discussion section compares three models in their ability to account for the patient's dissociation. It was suggested that models such as that of McCloskey, Caramazza, and Basili (1985), postulating a semantic representation for numbers built up on a base-ten system, are unable to account for the patient's errors. By contrast, Power et al.'s perspective (Power & Longuet-Higgins, 1978; Power & Dal Martello, 1990), which posits a semantic representation of numbers reflecting the structure of the verbal numeral system, could provide an economical interpretation for the dissociation observed between the mastery of sum and product relationships. Similarly, the asemantic transcoding model developed by Deloche and Seron (1987) gives a valid account for the patient's profile.