Chapter Four - Aphasia and the Bilingual Brain

Summary

In this chapter, we review work on a range of bilingual aphasias – the language impairments that occur due to a lesion or atrophy in the brain. We begin the chapter by discussing two theoretical approaches, namely the localizationist and dynamic accounts, which explain the extent to which one or both languages are affected. We see that the severity and type of aphasia that result from a lesion depends on its size and location. Additionally, a number of other nonlesion factors can affect the severity of the resulting aphasia. The premorbid variables that have been most studied are frequency of language use, AoA, and L2 proficiency. We then address how bilinguals are assessed for aphasia (e.g., the Bilingual Aphasia Test), and the possibilities for treatment and recovery. In this regard, the following important questions are discussed: In which language(s) should treatment be provided and what are the differential outcomes? If rehabilitation is given in only one language, is there cross-language generalization to the language not treated? We conclude that the most common pattern is parallel recovery in which both languages improve at a similar rate.