The importance of thematic informativeness in narrative discourse recovery in acute post-stroke aphasia

Abstract

Background: Discourse analysis allows the examination of functional and ecological language impairment in post-stroke aphasia. Given its complexity, various methods of analysis have been developed to measure the multiple components of discourse. Clinical assessment usually includes discourse analysis, but how clinicians should assess recovery of discourse, particularly in acute care settings, is still a matter of debate. Aims: This study aimed to measure improvements in discourse production in early post-stroke aphasia recovery. Methods & Procedure: Twenty-three persons with aphasia following a first left middle cerebral artery stroke were recruited in the stroke unit of Hôpital du Sacré-Coeur de Montréal (May 2015-July 2018). Patients treated with thrombolysis (n = 10) and untreated patients underwent two aphasia assessments (0 to 72 hours, 7 to 14 days post-onset). Discourse assessment consisted of the picture description task from the Western Aphasia Battery. Changes in microlinguistic and thematic informativeness measures between the two assessment periods were analyzed. Outcomes & Results: In-depth microlinguistic analyses showed no significant difference between the initial and follow-up assessments. Conversely, some thematic informativeness variables improved significantly during the same time period. Patients treated with thrombolysis produced more thematic units than untreated patients at both assessments, but the change between the two groups was not significant. Conclusions & Implications: This study suggests that thematic informativeness variables are sensitive to language improvement in early post-stroke aphasia recovery whereas no microlinguistic variables improved significantly in the same period. In contrast to previous evidence, the difference between patients treated with thrombolysis and untreated patients was not evident over time. The results suggest that thematic informativeness constitutes an interesting path to explore as a routine clinical assessment in acute-care settings because it is time-efficient, simple to conduct and reliable in assessing early changes in the discourse production of individuals with aphasia in the acute post-stroke phase.