Effects of Verb Network Strengthening Treatment (VNeST) Via Telerehabilitation on Word Finding in Post-stroke Aphasia.

Every year in Sweden, thousands of people suffer from stroke, often resulting in aphasia. One of the most common and persistent symptoms in aphasia is anomia, i.e., word finding difficulties. Anomia affects an individual's ability to communicate and can constitute an obstacle to active participation in social activities and working life with reduced quality of life as consequence.

Speech and language therapy has proved to be effective with significant training outcomes for people with aphasia (Brady, Kelly, Godwin, Enderby, & Campbell, 2016). However, concerning treatment of anomia a major challenge is to achieve generalization to untrained items and to connected speech. Most interventions train to name single words, with very little improvement in naming of untrained items, or generalization in daily language use (Kiran & Thompson, 2003; Kristensson et al., 2022). Typically, word-finding therapies target nouns. Training effects of verbs have been reported to a lesser extent and found to be smaller than that of nouns (Webster & Whitworth, 2012). Edmonds and coworkers (2009, 2011, 2014; Furnas & Edmonds, 2014) have developed an intervention protocol called Verb Network Strengthening Treatment (VNeST) which aims at improving production of nouns and verbs in sentence context by stimulating retrieval of verbs and possible subjects/agents and objects/patients for the given verbs (e.g., "The pupil writes a letter"). So far, results from single-case experimental design studies performed by Edmonds and colleagues are promising, showing generalization to untrained items and to other tasks (object naming, verb naming, and partly connected speech). The same promising results were observed even when Verb Network Strengthening Treatment (VNeST) was delivered remotely via a computer program (Furnas & Edmonds, 2014). In a single case experimental design study carried out by our group via telerehabilitation (Torinsson et al., submitted) in two individuals with mild-to-moderate and moderate-to-severe aphasia, we found that one participant improved significantly in word retrieval when producing sentences containing either trained verbs or semantically related verbs that were not targeted in treatment, suggesting generalization to untrained words. The other participant did not show any significant improvement for either trained or untrained items. Yet, an increase of production of correct information units (a measure of how informative verbal production is in an individual) could be observed in this participant four weeks after treatment. The results of this Swedish study seem to be in line with previous findings by Edmonds and colleagues. However, to our knowledge, the effects of intervention have not been investigated in larger groups of patients in a randomized controlled trial. Hence, this study aims to evaluate treatment effects of the VNeST protocol via telerehabilitation in individuals with post-stroke aphasia through a randomized controlled trial (RCT).

Outcome measures include measures of naming ability on word and sentence level as well as in connected speech. Measures of participant reported perception of functional communication as well as health related quality of life (PROMs) are also included.

Inclusion criteria

• Aphasia and subjective experience of word finding difficulties
• Diagnosed left hemisphere stroke at least six months post-onset
• With correction, sufficient hearing and vision to be able to participate in training and assessment.
• Sufficient stamina to be able to participate in training and assessment.
• Swedish as one of the first languages.

Exclusion criteria

• Other known neurological conditions
• Untreated epilepsy
• Severely impaired comprehension
• Moderate-severe dysarthria or apraxia of speech which may interfere with assessment.
• Speech-language treatment targeting specifically word finding during participation in the study.
• Participation in other studies/clinical treatment using Verb Network Strengthening Treatment (VNeST) during three months prior to the study.
• Active substance dependence