When assessing a bilingual aphasic, it is important to consider language assessment in both languages. Bilinguals with aphasia do not always have the same degree of severity in both languages. While abilities can be impaired in a similar way (parallel aphasia), it is also possible for abilities to be impaired to a different extent for each language (dissociated aphasia). Therefore, assessment in both languages is critical for determining the client’s strengths and weaknesses in both languages in order to get a clear picture of the client’s individual presentation of aphasia (Ardila, Aphasia Handbook, 157).
In addition, a monolingual aphasic’s prognosis for recovery is dependent upon aphasia type, aphasia severity, site of lesion, and size of lesion. On top of these factors, there are also many more factors that contribute to a bilingual aphasic’s prognosis of recovery: “pre-stroke language proficiency, balance of proficiency across languages, age of acquisition of each language, patterns of language use pre-stroke, phonological structure of each language”, etc (Kiran and Roberts, 37). Assessing clinicians have to perform an in-depth case history with any influential family members that are available, in order to determine the true severity of the client’s aphasia type. Comparison of pre-functioning and post-functioning language abilities in each language is crucial, otherwise erroneous assumptions and unrealistic goals can ensue. It would be inappropriate for the clinician to work as a language teacher by targeting skills that were not present pre-morbidly (Kiran and Roberts, 39). A clinician can attempt to determine the client’s levels of functioning prior to their stroke via self rating scales (if the client is capable of utilizing a number scale to indicate certain skills), family ratings, as well as determining language acquisition history and patterns of language use for each language (Kiran and Roberts, 40-41).
Kiran and Roberts propose two methods of determining the client’s post-morbid speech and language abilities: verbal fluency and narrative output. Verbal fluency allows a clinician to determine the client’s lexical production based on category or letter (i.e. name all the animals you can in one minute, dígame todas las palabras que empiezan con la letra “b” que sabe Ud.). It also serves as a basis for baseline data, as the clinician can compare the initial assessment performance with future performance on similar tasks. Narrative output is a good way to ascertain the client’s post-morbid language abilities in each language by utilizing a series of pictures to elicit a narrative. This can provide the clinician with a good picture of the client’s current skills regarding syntax, lexicon, morphology and discourse in each language. Again, these tasks can be used for measuring change over time (Kiran and Roberts, 46).
It is crucial that the clinician investigate the client’s morphological skills in each language, as bilingual aphasics, more so that monolingual aphasics, are susceptible to “compound processing impairment”, which means that they are likely to make errors of morphology for compound words – either through omissions or substitutions of morphological units in compound words (Libben, Aspects of Bilingual Aphasia, 54).
Written by: Taylor Viggers, MS, CF-SLP
Kiran, Swathi and Roberts, Patricia M.(2009) ‘Semantic feature analysis treatment in Spanish-English and French-English bilingual aphasia’, Aphasiology,, First published on: 31 August 2009 (iFirst)
Kiran S, Grasemann U, Sandberg C, Miikkulainen R. A Computational Account of Bilingual Aphasia Rehabilitation. Bilingualism (Cambridge, England). 2013;16(2):325-342. doi:10.1017/S1366728912000533.
Paradis, M., Libben, G., & Hummel, K. (1987) The Bilingual Aphasia Test. Hillsdale, NJ.: Lawrence Erlbaum. 32 + 127pp.