Longitudinal assessment of coherence in an adult with fluent aphasia: A follow-up study

Abstract

Background: It has been suggested that individuals with fluent aphasia demonstrate microlinguistic impairments and relatively preserved macrolinguistic abilities (Glosser & Deser, 1990). However, results of a previous study in which measures of sentence production, intersentential cohesion, and story grammar were assessed longitudinally over a period of 12 months did not support this contention (Coelho, Liles, Duffy, Clarkson, & Elia, 1994). In that investigation, as the individual with fluent aphasia recovered severity of aphasia decreased and microlinguistic abilities improved, but macrolinguistic skills remained quite limited. Aims: The present study sought to clarify the discrepancy between these two studies by re-analysing the narrative samples collected by Coelho et al. for adequacy of coherence in order for similar macrolinguistic measures to be compared across studies. Methods & Procedures: Two types of story narratives were elicited from a 55-year-old male with mild-moderate anomic aphasia on a monthly basis over a 12-month period. Story narratives were analysed for local and global coherence, and coherence ratings were compared to the mean performance of three matched non-brain-injured participants. Outcomes & Results: Neither local or global coherence improved appreciably over the 12-month period and both remained moderately impaired, inspite of gains noted in microlinguistic abilities. The individual with fluent aphasia also consistently demonstrated greater difficulties with global than local coherence. Conclusions: This pattern of impaired macrolinguistic abilities, is consistent with that of individuals with Alzheimer's disease and closed head injuries, and suggests that difficulty with discourse organisation may result from focal as well as diffuse brain pathology. These findings suggest the importance of expanding assessment procedures for individuals with aphasia, particularly mild aphasia, to include macrolinguistic dimensions of discourse organisation such as the analysis of coherence and story grammar-and further, that such macrolinguistic abilities need to addressed specifically in language therapy.