A contextual approach to facilitating word retrieval in agrammatic aphasia

摘要

Background: Although virtually all individuals with aphasia demonstrate problems with word retrieval, this symptom might arise for different reasons in individuals with different types of aphasia. A trade-off of dependence on semantic and syntactic information is hypothesised to underlie dissociations in word retrieval shown by fluent anomic and non-fluent agrammatic speakers. This division of labour predicts that strengthening semantic input will improve word retrieval for those with anomic aphasia, whereas strengthening syntactic input through contextual cues will improve word retrieval for those with agrammatic aphasia. Aims: To explore the outcome of a new treatment approach that proposes to improve word retrieval in individuals with agrammatic aphasia by implicitly strengthening the links between target words and associated words which co-occur in a connected speech context. Methods & Procedures: The outcomes of two therapy approaches were examined in two participants with agrammatic aphasia. One therapy approach focused on explicitly training semantic features of target words; the other, more novel, approach focused on implicitly strengthening contextual associations through story telling and retelling. It was predicted that the latter approach would result in greater benefits for the two agrammatic participants. Outcomes & Results: Although both therapy approaches appeared to be effective, the predicted advantage of the contextually based approach was not found. The evolution of the error patterns throughout the treatment was examined to help understand the mechanisms underlying the improvements shown for each participant. Conclusions: A novel treatment involving training words in a story context was shown to result in improved word retrieval for two participants with agrammatic aphasia. The merits of the approach are discussed, relative to more traditional explicit word retrieval therapy approaches.