Cross-Modality Treatment Generalization in Sentence Comprehension in Aphasia: Evidence From Structural Priming and...

Acquired neurogenic communication disorders such as aphasia are associated with sentence production and comprehension difficulties. However, sentence-level treatments for aphasia do not consistently yield generalized gains across modalities, from production to comprehension or vice versa. This limits the effectiveness of current aphasia treatments. In this study, we present structural priming, the phenomenon where repeated grammatical structures are used more frequently and are easier to process, as a potentially effective treatment for sentence-level deficits in aphasia, and one which may achieve generalization from production to comprehension. Further, we assessed whether lexical overlap between prime and target sentences (lexical boost) affected the strength of cross-modality generalization.

24 people with aphasia (PWA) and 16 age-matched controls completed a structural priming sentence production treatment. Their comprehension of trained structures (passives and double-object datives) was tested with a sentence-picture matching task before and after training to assess cross-modality generalization effects. Eye movements were recorded during the comprehension task using webcams.

Response times and fixation times to the target picture were facilitated from pre- to post-training, although comprehension accuracy remained stable. While controls were more facilitated by same-verb priming, PWA benefited more from different-verb priming. Improvements in sentence production during training were related to the strength of improvements on the comprehension task across groups. These results suggest that structural priming has the potential to achieve cross-modality transfer of treatment gains and different-verb priming may be more effective in aphasia than same-verb priming.

What is already known on the subject Acquired neurogenic communication disorders such as aphasia are associated with sentence production and comprehension impairments. However, sentence-level treatments for aphasia do not consistently yield generalized gains across modalities, from production to comprehension or vice versa. This severely limits the effectiveness of current treatments. What this study adds to existing knowledge In this study, we present structural priming, the phenomenon where repeated grammatical structures are used more frequently and are easier to process after exposure, as an effective treatment for sentence-level deficits in aphasia, and one which achieves reliable generalization from production to comprehension. Further, we assessed whether lexical overlap between prime and target sentences (lexical boost) affected the strength of cross-modality generalization. Eye movements were tracked using webcams, which offers a novel and accessible method of online data collection for communication disorders. What are the clinical implications of this study? Our results make the case for structural priming as a reliable treatment component for sentence production and comprehension in aphasia, which achieves cross-modality transfer of treatment gains. Eye movements were reliably recorded through webcams.