Published online by Cambridge University Press: 19 September 2019
Inflection impairments are commonly noted in aphasia, particularly non-fluent variants, where descriptions of such difficulties often focus on inflection omission. This aligns with rule-based theory, in which inflected forms should be more difficult to produce than their uninflected counterparts. Recent studies address noun inflection for number and potential effects of the relative frequency of singular and plural forms (dominance effects). However, none examine number errors qualitatively or in spontaneous speech. We present quantitative and qualitative analyses of such errors in nouns produced by twelve people with aphasia in spoken Cinderella narratives, examining: error rate; error types and nouns involved; relationship between error production and dominance; and speakers’ consistency with error production and flexibility in varying the noun forms concerned. Twelve unimpaired speakers provide comparison data. While error rates were low, arguably more important is error type. Singularisation and pluralisation errors were observed, all on regular nouns and involving production of the dominant form. The pluralisation errors, all occurring on references to Cinderella’s glass slipper, arguably challenge rule-based predictions that the singular is easier to retrieve than the plural. We suggest constructivist, usage-based theory as a promising framework to characterise such productions. Implications for aphasiology and clinical practice are also discussed.
We wish to thank all participants for generously donating their time and energy to this study. We are also grateful to Ruth Herbert for suggestions about data collection, Janet Webster for kindly sharing the data from the unimpaired speakers, Bodo Winter for advice on specific analytical points, and Gareth Carrol, Jack Grieve, Nicholas Groom, Ruth Herbert, and Marcus Perlman for comments on earlier drafts. This work was partly funded by the University of Sheffield’s Faculty of Medicine, Dentistry and Health (Faculty Prize Scholarship). Elena Lieven’s research is supported by a grant to the ESRC International Centre for Language and Communicative Development (LuCiD: <www.lucid.ac.uk>). The support of the Economic and Social Research Council [ES/L008955/1] is gratefully acknowledged. Part of this work was completed for the first author’s PhD at the University of Sheffield.