Model-driven intervention in bilingual aphasia: Evidence from a case of pathological language mixing

Background: Speech-language pathologists are meeting an increasing number of bilingual clients. This poses a special challenge to clinical practice, given that bilingualism adds to the complexity of aphasia patterns and clinical decisions must be made accordingly. One question that has come to the attention of clinical aphasiologists is that of the language in which therapy should be administered. This issue becomes particularly relevant in cases of involuntary language switching, when choosing between L1 and L2 implies inhibiting one of the languages. Models of lexical selection in bilingual people offer a rationale for language choice based on the specificities of bilingual aphasia within each client. Aims: To provide evidence for model-based intervention in bilingual aphasia, particularly in cases of pathological language switching. Methods & Procedures: This paper reports a model-driven intervention in a case of involuntary language switching following aphasia in a Spanish-English bilingual client. Outcomes & Results: Intervention tailored to the client's strengths resulted in improved communication skills thanks to the implementation of a self-regulated strategy to overcome involuntary language switching. Conclusions: Model-driven descriptions of bilingual aphasia contribute to efficient intervention by identifying therapy approaches that take account of each client's language abilities. Further, clinical data analysed within models of bilingual language processing can provide evidence for dissociations between components of the bilingual lexical system.