Abstract
INTRODUCTION: The impact of bilingualism on speech-language assessment and therapy in primary progressive aphasia (PPA) remains underexplored, despite its suggested influence on disease presentation. METHODS: A bilingual Italian (L1)-English (L2) individual with logopenic-variant PPA completed a bilingual assessment as well as dual-language lexical retrieval therapy (LRT). His bilingual experience was characterized in detail, and therapy outcomes were evaluated within and across languages. RESULTS: Pre-morbidly, the patient was a relatively balanced bilingual individual with stronger L1 literacy. Following disease onset, L2 showed faster decline, whereas L1 remained stable. Age at acquisition, dominance, and language use were among the main factors contributing to his language maintenance and decline. Therapy yielded relatively equivalent item-specific gains in both languages (L1 d (2 )= 5.0; L2 d (2 )= 5.6), asymmetric crosslinguistic transfer to L2 > L1, and modest functional improvements. DISCUSSION: Findings support the relevance of in-depth bilingual assessment and therapy to guarantee successful treatment in PPA, unveiling the relevance of bilingual experience in shaping treatment outcomes.