Formal lexical paragraphias in a single case study: How `masterpiece' can become `misterpieman' and `curiosity' `suretoy.'

Formal lexical errors are relatively rare in the production of aphasic patients. In this study, we report the case of DW, who makes a high proportion of these errors. A few other cases have previously been reported, but DW shows a number of distinguishing characteristics. First, formal lexical errors are made in spelling and not in spoken speech. Second, they are associated with morphological errors and not with semantic errors. Third, they often combine lexical units in ways which are semantically and morphologically illegal. Finally, the majority of morphological errors involve the insertion, rather than the deletion, of suffixes. This pattern can be explained by hypothesizing that DW's errors arise because of confusions among a cohort of lexical neighbors activated top-down from a phonological input and bottom-up from shared letters. One possible cause of the confusions is lack of proper inhibition among lexical competitors. (C) 2002 Elsevier Science (USA). All rights reserved.