Response to contrasting verb retrieval treatments: A case study

Abstract

Verb retrieval treatments for individuals with aphasia that have led to greater improvements in sentence production typically have incorporated semantic as compared to repetition treatments. However, studies have not contrasted treatments within subjects to compare treatment effectiveness. We compared effects of sequential verb retrieval treatments in one participant and analysed effects on sentence production. We tested one woman, WR, with nonfluent aphasia and mild verb retrieval impairment related to semantic dysfunction. She participated in three phases of verb retrieval treatment, semantic, phonologic, and rehearsal, in a multiple baseline crossover design. We examined accuracy of picture naming and sentence production for trained and untrained verbs. All treatments resulted in significantly improved naming of trained verbs, some generalised sentence production, and no improvement for untrained verbs. No difference was evident in effects across treatments. Unlike earlier studies, the repetition and phonologic treatments were as effective as semantic treatment for improving sentence production. These positive findings for all three treatments may relate to semantic activation that occurs whenever a word is retrieved in the context of picture presentation, thereby fundamentally altering semantic activation patterns and making the word more easily accessible in subsequent retrieval attempts, whether in isolation or in sentences.