The effects of verb retrieval therapy for people with non-fluent aphasia: Evidence from assessment tasks and conversation

Abstract

Despite often impressive improvements on linguistic assessments, there is a lack of evidence of significant generalisation from impairment-focused aphasia therapy to everyday communication. The aim of the current study was to investigate the effect of a verb retrieval therapy across a range of levels of language production. Nine participants with chronic non-fluent stroke aphasia were recruited into this case series. Baseline assessment included naming a range of verbs (i.e., action verbs, semantically light verbs and personally relevant verbs) and sentence production. Multiple samples of conversation were collected from each participant and his/her partner. Consecutively failed verbs were divided across treatment and control sets; these sets were matched for salient psycholinguistic variables such as frequency, imageability and argument structure. A multi-component verb retrieval therapy was delivered, consisting of semantic feature analysis, gesture production and phonemic cueing. Following therapy, participants demonstrated significant and sustained gains in naming treated verbs; more modest effects were seen in untreated verbs. Mixed patterns of generalisation were evident in assessment of sentence production. In conversation, while group analysis suggested a lack of change, individual analyses indicated increased verb retrieval for three participants and qualitative changes related to the syntactic contexts of verbs retrieved.

Keywords:

• Multi-component verb retrieval therapy
• Conversation

We would like to thank Dr. Andrew Stewart and Prof. Matt Lambon Ralph for their invaluable support with statistics. We would also like to gratefully acknowledge the time, effort and enthusiasm of the participants with aphasia and their families who took part in the study. FUNDINGThis work is supported by a Research Bursary from the Stroke Association [TSA JRTF 2009/01].