ACQ Vol 13 No1 2011

Language disorders

Effects of topic familiarity on discourse in aphasia A single case study Adrienne Miles, Natalie Ciccone, and Erin Godecke

This paper presents an investigation into the effect of topic familiarity on discourse production in an individual with chronic post-stroke aphasia. The participant produced procedural narrative discourse samples within a retell context with the topics identified as familiar or unfamiliar by the participant. To establish the level of familiarity the participant ranked 20 topics from most to least familiar. The five most and least familiar topics were then used as discourse sample stimuli. These samples were compared on multiple discourse measures in order to examine the impact of topic familiarity across different levels of the language system. Overall the unfamiliar procedural topics resulted in less successful communicative output. The results of this study lend support to literature suggesting topic familiarity influences discourse production. This study has clinical implications for the assessment and treatment of individuals with aphasia. D iscourse production results from the interplay between social, linguistic, and cognitive elements of a communication setting (Ulatowska & Bond, 1983) and so discourse analyses may investigate interactions between the linguistic and cognitive processes which affect communication in people with aphasia (Armstrong, 2000; McNeil, Doyle, Fosset, Park, & Goda, 2001). Discourse analysis is widely used to examine communication in people with aphasia (Sherratt, 2007). It provides an opportunity for the production and analysis of complex communicative elements that may not be as obvious in standardised assessment tasks requiring single word production or comprehension (Armstrong, 2000). Due to the interaction between linguistic and cognitive processes, variables external to an individual’s language system can significantly influence the efficiency and effectiveness of the system and impact on communicative success (McNeil, Odell, & Tseng, 1991). External variables, such as discourse topic or the method of discourse elicitation, influence the quality and characteristics of the discourse produced (Armstrong, 2000; Li, Williams, & Della

Volpe, 1995; Williams, Li, Della Volpe, & Ritterman, 1994). These external variables can potentially be manipulated within a clinical environment to influence the characteristics of the discourse sample produced. One such element is topic familiarity (McNeil et al., 2001). Limited available research examines the relationship between topic familiarity and discourse production in people with aphasia. Within their study Williams et al. (1994) asked a group of 30 non-brain-damaged individuals to rate a list of 84 topics on a scale of very familiar to completely unfamiliar. From the ratings a list of 10 familiar and 10 unfamiliar topics was generated. Using these topics Williams et al. (1994) investigated the impact of topic familiarity on procedural discourse and story retell production by people with aphasia and non-brain-damaged individuals. The study found familiar and unfamiliar topics affected procedural discourse and story retells differently. The authors reported significant positive effects of familiar topics, such as increased quantity of speech for both procedural discourse and story retell samples, and increased grammatical complexity in story retells. Conversely, unfamiliar topics resulted in the production of more content words in story retells and a greater level of grammatical complexity in procedural discourse samples (Williams et al., 1994). Using the familiar and unfamiliar topics generated in the Williams et al. (1994) study, Li et al. (1995) analysed procedural discourse and narrative retells produced by people with aphasia and non-brain-damaged individuals. They investigated the production of essential and optional ideas in procedural discourse samples on familiar and unfamiliar topics. Essentials ideas were classified as points that were essential to completion of the procedure. Optional ideas were non-essential points that acted to further clarify or support the essential ideas. The analysis of essential and optional ideas was based on previous research that found, within a structured elicitation context, that people with aphasia convey information that is essential for the completion of a procedure; however, they include less elaborative or optional content when compared to individuals without aphasia (Ulatowska, Freedman-Stern, Doyel, Macaluso-Haynes, & North, 1983). Li et al. (1995) found that the discourse samples on familiar and unfamiliar topics contained the same number of essential ideas but unfamiliar topics elicited fewer optional ideas. Similar results were found in the story retell context in which participants recalled more story details in response to familiar topics (Li et al., 1995). Taken together, the Williams et al. (1994) and Li et al. (1995) studies demonstrated that topic familiar discourse

Keywords APHASIA TOPIC FAMILIARITY DISCOURSE

This article has been peer- reviewed

Adrienne Miles (top), Natalie Ciccone (centre)

and Erin Godecke

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ACQ Volume 13, Number 1 2011

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