Words and number words transcoding: A retrospective study on 57 aphasic subjects

Alphabetically written numbers are of particular interest because they stand at the boundary between the domain of words and the domain of numbers whose dissociation has been repeatedly reported in single case studies.In this retrospective study we analyze the performance of a series of left-brain-damaged aphasic subjects in reading aloud, repetition and writing to dictation of words and number words in order to explore in an unselected group of aphasic subjects the effect of the type of stimulus.57 Aphasic subjects underwent a language examination test and a calculation and number processing battery that included repetition, reading aloud, and writing to dictation of words and number words.Performance for words was better than performance for number words in all tasks, while writing to dictation was the more difficult task for both types of stimuli. An analysis of error type showed that phonological paraphasias were the most frequent error in word reading and repetition, whereas lexical substitutions were the most frequent error in number words reading and repetition.This result supports the hypothesis of a dissociation between transcoding of words and number words: the analysis units appear to be phonemes in words transcoding and single digit words in number words transcoding.