The effect of processing semantic features on spoken word retrieval in a case series of people with aphasia

Purpose: There is a growing body of evidence showing the benefit of Semantic Feature Analysis in the treatment of word finding abilities in people with aphasia. The original technique was grounded in the hypothesis that the activation of semantic features spreads to the target and thereby facilitates its subsequent retrieval. However, it remains unclear the extent to which the focus on semantic features influences the treatment effects. The aim of this study was therefore to shed light on this issue by examining the effect of priming with semantic features (parts and functions) on target retrieval across a case series of people with aphasia. Method: 10 people with aphasia and word retrieval impairments were primed with spoken forms of words that were either the target name (identity condition, e.g. car), parts of the target (e.g. wheel) or functions of the target (e.g. drive) before later being asked to name a picture of that target. An unrelated prime condition (e.g. employ) was used as a control for test-retest effects. Result: At a group level, there was speeding of reaction times in picture naming in the identity condition relative to the unrelated condition; however, no effect of priming was found for either parts or functions. There was significantly better response accuracy in post-priming naming, but this effect did not reach significance for any individual experimental condition (identity, parts, functions) as compared to the unrelated condition, although the identity condition showed numerical improvement while the other two conditions showed decline. Conclusion: Given the lack of evidence for facilitatory effects from parts and functions of a target in a priming task, this research suggests that further research is warranted on the extent to which the improvement in word retrieval subsequent to Semantic Feature Analysis is caused by the emphasis on production of semantic features rather than from the repetition of the target name.