Development of an aphasia treatment targeting verbs with low concreteness

The verb plays a critical role in sentence production, but verb production is commonly impaired in aphasia. The verb is therefore an important treatment target for aphasia treatments. The verb appears to have a network structure of meaning within the mental lexicon, and existing treatments, such as Verb Network Strengthening Treatment (VNeST) and “verb is core” treatment approach naming rehabilitation theoretically by expanding this network structure. However, these and other verb naming treatments have focused nearly exclusively on verbs with high concreteness ratings. While high concreteness verbs are useful and common, recent evidence highlights the utility and frequency of low concreteness verbs in spoken language also. Thus the focus of current verb treatments on verbs with high concreteness omits a set of verbs that are potentially useful for persons with aphasia. Therefore, a treatment was designed to improve the accuracy of low concreteness verb naming in persons with aphasia. The novel treatment was largely based on VNeST and emphasized the network structure of the mental representation of target verbs by pairing them with common subjects and objects. Three adult persons with nonfluent aphasia participated in a single-subject research design study examining the feasibility of the treatment for improving verbal naming of low concreteness verbs. Results from the study indicated possible changes associated with the treatment for two of the three participants, though these changes were limited in magnitude. Treatment performance data suggested possible improvements in verb processing that were not reflected in the primary outcome measure. Thus, future research is warranted and should focus on further enriching the mental verb network representations of target verbs with low concreteness and on refining relevant outcome measures.