Structural Priming Treatment in Aphasia: The Role of Lexical and Abstract Syntactic Representations

Sentence production is impaired in many persons with aphasia (PWA). However, few effective treatments for sentence production exist. Recent research has advanced structural priming as a promising treatment for aphasia, but the underlying mechanisms of priming remain unclear. This study examined contributions of abstract syntactic and lexically boosted priming to sentence production improvements in PWA and underlying memory mechanisms.

Twenty-four PWA and 16 age-matched controls completed baseline testing, three to six sessions of sentence production priming training, and 1-day and 1-week posttesting. Trained structures were passives and double-object datives. Participants were trained with same-verb and different-verb priming to assess lexical boost and abstract syntactic priming effects on treatment outcomes. The serial reaction time, fragmented picture, and picture pointing span tests were administered to assess contributions of implicit and explicit memory in predicting treatment gains.

PWA and controls showed lasting improvements to both trained and untrained sentences following training. Critically, controls improved more strongly following same-verb priming, while PWA showed stronger gains following different-verb priming. High implicit memory scores facilitated greater treatment effects in both PWA and controls. Only controls showed positive effects of explicit memory.

These results support structural priming as an effective sentence production treatment for PWA, especially when verbs are not matched between primes and target. We suggest lexical differentiation supports priming in PWA by allowing more efficient access and learning of abstract syntactic representations, which appears crucial to successful sentence production.