June 5, 2012 Features

One Disorder, Multiple Languages

see also

You have a new outpatient client who had a stroke a year ago and has aphasia. Mrs. R. is 63 years old and multilingual. She was born in Colombia, South America, and spoke Spanish as a child and young adult. She studied and learned to speak French in college and spent a summer in France. She moved to North America when she was 22 and married an American who speaks only English. In which language will you provide treatment? Would you provide treatment in Spanish, the first acquired language, or in English, the language learned later but the one the client has been speaking with her immediate family?

More speech-language pathologists face this sort of conundrum every day as they work with the country's growing multilingual population. The challenge here is that research to date has only begun to uncover the optimal rehabilitation for multilingual clients with aphasia (Gitterman, Goral, & Obler, 2012). But the literature is still sparse in terms of interpreting impairment and recovery in this group (Faroqi-Shah, Frymark, Mullen, & Wang, 2010; Lorenzen & Murray, 2008). What we do know from existing research on the influence of multilingualism on language processing can help us evaluate and treat multilingual individuals with aphasia.

Some key points about multilingual language processing have direct implications for aphasia services to multilingual people.

Constant Change

Research has convincingly demonstrated that language processing in a multilingual person is a dynamic process. Thus, learning a second language (L2) changes representations and access not only for that language but also for the first-acquired language (L1) (Cook, 2003; Goral, Libben, Obler, Jarema, & Ohayon, 2008; Linck, Kroll, & Sunderman, 2009; Witford & Titone, 2012). For instance, Linck and colleagues (Linck et al., 2009) demonstrated that immersion experience in L2 results in attenuation of L1, indicating that increased dominance in L2 may result in attrition or decreased accessibility to L1, at least in the short term.

Implications for aphasia: The dynamic nature of language dominance, including factors such as attrition and immersion, needs to be considered when evaluating impairment in the multiple languages of multilinguals and deciding which language to treat. It is reasonable to expect that Mrs. R., because she has been living in the United States for the past 40 years, may have experienced some attrition in her Spanish, and that English may have become her dominant language. In this scenario, it may be reasonable to administer treatment in English, which may be the client's stronger or more used language.

All Systems Switched On

All language systems are active during language processing tasks—during code-switching and translation, but also during word recognition and production and during sentence processing. Therefore, the non-target language is never actually switched off across tasks, even when the task requires only one language output (Costa, 2005; Kroll, Bobb, & Wodniecka, 2006; Marian, Spivey, & Hirsch, 2003). Language systems operate concurrently in highly proficient multilinguals and also in differentially proficient multilinguals (Christoffels, Firk, & Schiller, 2007; Costa & Santesteban, 2004; Herman, Bongarts, De Bot, & Schreuder, 1998). In these individuals, L1 must be inhibited to produce a less dominant language; therefore, there is a lag in the reactivation of L1 when switching from L2 to L1.

Implications for aphasia: Understanding that all languages are active during language processing tasks can greatly affect an SLP's approach. If target words and structures are active across languages, then training in one language should result in changes in all languages—that is, language treatment should facilitate cross-language generalization. Several recent treatment studies have demonstrated this general finding (Edmonds & Kiran, 2006; Goral, Levy, & Kastl, 2010; Kiran & Roberts, 2009; Laganaro & Overton Venet, 2001; Miertsch, Meisel, & Isel, 2009). For Mrs. R., if treatment can be provided in only one language—Spanish or English—the clinician can reasonably expect positive cross-language generalization.

However, if all languages are always active, a greater likelihood of interference among the languages may be more likely when the client is experiencing word-retrieval difficulties in one language. This premise may be particularly true when treatment is in the less dominant language—that is, when treatment requires inhibition of the more dominant language (Abutalebi, Rosa, Tettamanti, Green, & Cappa, 2009; Goral, 2012). In the example of Mrs. R., if one of her two main languages—English or Spanish—seems to be markedly more accessible to her, it may make sense to work in that language. Working in the language that is less accessible may interfere with performance in the more accessible language, at least for the duration of the treatment.

This premise would be true as well for Mrs. R.'s French (L3), her least proficient language. Therefore, if Mrs. R. demonstrates good recovery of her two stronger languages and expresses interest in recovering her abilities in her third language, it is reasonable to explore additional work in that language. However, treatment in French is less likely to advance her stronger English and Spanish.

Overlapping Neural Systems

There are structural and functional consequences of being multilingual. Functional MRI studies have shown that the neural systems engaged by bilinguals' two languages overlap to a great extent (Abutalebi & Green, 2007; Indefrey, 2006; Sebastian, Laird, & Kiran, 2011). We also know that activation patterns during multilingual language processing tasks are driven by language proficiency (Abutalebi, 2008; Sebastian et al., 2011). When the degree of proficiency in multilinguals is very high, a common language system comprising the left hemisphere language network appears to be responsible for the processing of both languages (Chee, Hon, Lee, & Soon, 2001; Perani et al., 2003). In low-proficient languages, however, there is a more extended network of activations that includes brain regions related to speech motor planning and cognitive functions (Abutalebi et al., 2009; Stein et al., 2009).

Implications for aphasia: It is likely that after brain damage, the same mechanisms involved when predicting the neural substrates of language recovery in monolingual aphasia are also true in multilingual aphasia. Multilingual Spanish-English clients with aphasia activate perilesional left-hemisphere regions for their more proficient language and a broader network, including right-hemisphere regions, for the less proficient language (Sebastian, Kiran, & Sandberg, 2012). The redundancy of the neural regions may support language recovery in ways that are facilitative. Therefore, engaging in treatment tasks that tap into multiple languages may also strengthen recovery-related changes at the neural level.

Cognitive Consequences

Research on multilingual language processing indicates that multilingualism may offer cognitive advantages throughout the lifetime. In language processing, multilinguals activate all languages, but they must suppress the non-target language(s). In doing so, multilinguals recruit the executive control system in a way that monolinguals do not, and this system is reinforced throughout the lifetime as the languages continue to be used. Researchers suggest that multilinguals' inhibitory processes may afford advantages in attention control and postpone the decline of cognitive control (Bialystok, Craik, Klein, & Viswanathan, 2004; Gollan, Sandoval, & Salmon, 2011; Kavé, Eyal, Shorek, & Cohen-Mansfield, 2008).

Additionally, multilinguals have been shown to develop dementia later than monolinguals, suggesting that multilingualism contributes to cognitive reserve (Craik, Bialystok, & Freedman, 2010). However, this cognitive reserve may allow for greater neuropathy accumulation before symptoms manifest, a premise suggested by the greater atrophy found in bilinguals with probable Alzheimer's disease as compared to monolinguals (Schweizer, Ware, Fischer, Craik, & Bialystok, 2011).

Implications for aphasia: The cognitive implications of multilingualism can influence the approach to rehabilitation in multilingual people with aphasia. For instance, it may be possible that working with them on cognitive exercises targeting inhibition and suppression may help them control the language in which they are conversing. Such exercise could perhaps also limit cross-language interference or pathological switching (Penn , Frankel, Watermeyer, & Russell, 2010). However, it is also possible that if multiple languages are represented on the same neural substrates, a multilingual person may be more susceptible to aphasia and may have greater language deficits relative to monolinguals (Wong & Kiran, submitted).

Considerations for Clinicians

Studies that systematically examine assessment and intervention with multilinguals with aphasia are ongoing. The results are preliminary, and many questions remain unanswered. Nevertheless, some suggestions may help clinicians working with these clients.

Understand clients' pre- and post-stroke language use and background. A clinician's thorough understanding of the client's history and patterns of language acquisition, mastery, and use for each of his or her languages may improve assessment and intervention. Gather information from the client and people familiar with the client's history [PDF] and integrate the evidence (e.g., Adrover-Roig, Marcotte, Scherer, & Ansaldo, 2012; Kiran & Roberts, 2012).

Multilingual aphasia is not categorical: Deficits in each language lie on a continuum. Use terms of relative impairment and relative recovery in determining whether all the clients' languages were similarly affected and consider pre-morbid proficiency when determining parallel patterns of impairment post-stroke (Gray & Kiran, submitted; Paradis, 2004). For example, clients who were not equally proficient in all their languages prior to the stroke, and do not demonstrate comparable abilities in all their languages following the stroke, can be considered to show parallel impairment, despite differences in the absolute impairment, if the relative proficiency post-stroke mirrors their relative abilities pre-stroke.

Understand the limits of assessment tools. Assessment results may be influenced by the limitations of and differences among assessments. Translated tests may introduce biases of items and levels of difficulty. Even tests carefully adapted to multiple languages (the Bilingual Aphasia Test; Paradis & Libben, 1987) have limitations (see special issues in Clinical Linguistic and Phonetics, 2011, and Journal of Neurolinguistics, 2012). Use open-ended assessments, such as verbal fluency, picture narrative description, and personal narratives to augment or replace translated tests (Altman, Goral, & Levy, in press; Roberts & Kiran, 2007). Be aware of measurement errors introduced when working with a translator who is a family member or a caregiver of the client.

Choosing a Language

Using everything you know about the multilingual patient's language history, you will need to make an informed decision about which language to train.

  • Treating one language does not mean you are jeopardizing the other language. Clinicians may decide to treat one or all languages of the clients. Positive cross-language effects may occur in some cases. However, a given treatment session should have a clear target language to reduce confusion and frustration. If the same brain regions are likely to process all the languages in a multilingual, then the brain regions engaged in treatment are probably the same for the client's second or third language, especially for multilinguals who achieved high proficiency in all their languages.
  • Consider the client's language background and relative strength of languages. If you select one language for treatment, consider many factors, including the client's choice and relative proficiency/accessibility. In contrast, treating one language may facilitate languages of comparable accessibility (Edmonds & Kiran, 2006; Kohnert & Peterson, 2012). Thus, a stronger language may be an ideal choice when only one language is treated.
  • Make informed decisions about code-switching and translation. Code-switching and translation may be useful for some clients (Ansaldo, Saidi, & Ruiz, 2010; Goral, Levy, Obler, & Cohen, 2006), but may promote cross-language competition and interference in others. Nevertheless, don't discourage code-switching and code-mixing if they help the client maximize communication and the communication partners can communicate in all languages. There are no clear findings on what variables determine these patterns, so clinicians may want to adjust intervention strategies for individual clients on the basis of their own experience.
  • Consider clients' personal preferences, as well as cultural and sociolinguistic contexts. Decisions about treatment language should respect the linguistic context and preferences of the client. If maintaining multilingual communication abilities is important to the client, there is no need to limit treatment and communication to only one language (Penn, 2007).

Future Trends

We need to know more about the complexities of accurate assessment, maximizing treatment efficacy, and cross-language influence in multilingual aphasia. Future studies would contribute to our understanding and rehabilitation of multilingual aphasia by focusing on:

  • The circumstances—including relative language proficiency and language similarities—under which intervention in one language benefits the untreated languages.
  • The time-course and maintenance effects of cross-language facilitation and inhibition.
  • Best strategies to incorporate natural multilingual behaviors, such as code-switching, to maximize treatment efficacy.
  • Effects of treating multiple languages during the same period and during a single session in the context of multilingual and monolingual sessions.

Swathi Kiran, PhD, CCC-SLP, is associate professor in the Department of Speech, Language, and Hearing Sciences at Boston University. She is director of its Aphasia Research Laboratory and research director of the Aphasia Resource Center. Her research and clinical interests include bilingual aphasia, aphasia rehabilitation, functional neuroimaging, language recovery, and impairments in naming, reading, and writing. She is an affiliate of ASHA Special Interest Groups 2, Neurophysiology and Neurogenic Speech and Language Disorders, and 14, Communication Disorders and Sciences in Culturally and Linguistically Diverse Populations. She is a recipient of the American Speech-Language-Hearing Foundation 2008 Clinical Research Grant. Contact her at kirans@bu.edu.

Mira Goral, PhD, CCC-SLP, is a professor at Lehman College and the Graduate Center of the City University of New York and director of the Lehman College Neurolinguistics Laboratory. Her research interests include multilingualism, aphasia, language attrition, and language and cognition in aging. She is an affiliate of ASHA Special Interest Group 2. Contact her at mira.goral@lehman.cuny.edu.

cite as: Kiran, S.  & Goral, M. (2012, June 05). One Disorder, Multiple Languages. The ASHA Leader.


Abutalebi, J. (2008). Neural aspects of second language representation and language control. Acta Psychologica, 126, 466-478.

Abutalebi, J., & Green, D. (2007). Bilingual language production: The neurocognition of language representation and control. Journal of Neurolinguistics, 20, 242–275.

Abutalebi, J., Rosa, P. A., Tettamanti, M., Green, D. W., & Cappa, S. F. (2009). Bilingual aphasia and language control: A follow-up fMRI and intrinsic connectivity study. Brain and Language, 109(2–3), 141–156. doi: S0093-934X(09)00040-6 [pii]10.1016/j.bandl.2009.03.003.

Adrover-Roig, D., Marcotte, K., Scherer, L. C., & Ansaldo, A. I. (2012). Bilingual aphasia: neural plasticity and considerations for recovery. In M. Gitterman, M. Goral, & L.K. Obler (Eds.) Aspects of Multilingual Aphasia. Chapter 2. Bristol, UK: Multilingual Matters.

Altman, C., Goral, M., & Levy, E. S. (in press). Integrated narrative analysis in multilingual aphasia. Aphasiology.

Ansaldo, A., Saidi, L., & Ruiz, A. (2010). Model-driven intervention in bilingual aphasia: Evidence from a case of pathological language mixing. Aphasiology, 24(2), 309–324. doi:10.1080/02687030902958423.

Bialystok, E., Craik, F. I., Klein, R., & Viswanathan, M. (2004). Bilingualism, aging, and cognitive control: Evidence from the Simon task. Psychology and Aging, 19(2), 290–303.

Chee, M. W., Hon, N., Lee, H. L., & Soon, C. S. (2001). Relative language proficiency modulates BOLD signal change when bilinguals perform semantic judgments. Blood oxygen level dependent. NeuroImage, 13(6 Pt 1), 1155-1163. doi: 10.1006/nimg.2001.0781S1053811901907815 [pii].

Christoffels, I. K., Firk, C., & Schiller, N. O. (2007). Bilingual language control: An event-related brain potential study. Brain Research, 1147, 192–208. doi: S0006-8993(07)00268-5 [pii]10.1016/j.brainres.2007.01.137.

Cook, V. (2003). Effects of the Second Language on the First. Bristol, UK: Multilingual Matters.

Costa, A. (2005). Lexical access in bilingual production. In Judith F. Kroll and Annette M. de Groot (Eds), Handbook of bilingualism: Psycholinguistic approaches (pp. 289–307). New York: Oxford University Press.

Costa, A., & Santesteban, M. (2004). Bilingual word perception and production: Two sides of the same coin? Trends in Cognitive Science 8(6), 253; author reply 254. doi: 10.1016/j.tics.2004.04.005 S1364661304001044 [pii].

Craik, F. I., Bialystok, E., Freedman, M. (2010). Delaying the onset of Alzheimer disease: Bilingualism as a form of cognitive reserve. Neurology, 75, 1726–17269.

Edmonds, L., & Kiran, S. (2006). Effect of semantic based treatment on cross linguistic generalization in bilingual aphasia. Journal of Speech, Language and Hearing Research, 49(4), 729–748.

Faroqi-Shah, Y., Frymark, T., Mullen, R., & Wang, B. (2010). Effect of treatment for bilingual individuals with aphasia: A systematic review of the evidence. Journal of Neurolinguistics, 23, 319–341.

Gitterman, M., Goral, M., & Obler, L. K. (2012). Aspects of Multilingual Aphasia. Bristol, UK: Multilingual Matters.

Gollan, T., Sandoval, T., & Salmon, D. P. (2011). Cross-language intrusion errors in aging bilinguals reveal the link between executive control and language selection. Psychological Science, 22, 1155–1164.

Goral, M. (2012). Cross-language treatment effects in multilingual aphasia. In M. Gitterman, M. Goral, & L. K. Obler (Eds.), Aspects of Multilingual Aphasia. Chapter 7. Bristol, UK: Multilingual Matters.

Goral, M., Levy, E. S., Obler, L. K., & Cohen, E. (2006). Lexical connections in the multilingual lexicon. Brain and Language, 98, 235–247.

Goral, M., Libben, G., Obler, L. K., Jarema, G., & Ohayon, K. (2008). Lexical attrition in younger and older bilingual adults. Clinical Linguistics and Phonetics, 22, 509–522.

Goral, M., Levy, E. S., & Kastl, R. (2010). Cross-language treatment generalization: A case of trilingual aphasia. Aphasiology, 24(2), 170–187.

Gray, T. & Kiran, S. (submitted).A theoretical account of lexical and semantic deficits in bilingual aphasia. Manuscript submitted for publication.

Herman, D., Bongarts, T., De Bot, K., & Schreuder, R. (1998). Producing words in a foreign language: Can speakers prevent interference from their first language? Bilingualism: Language and Cognition, 1, 213–229.

Indefrey, P. (2006). A meta-analysis of hemodynamic studies on first and second language processing: Which suggested differences can we trust and what do they mean ? Language Learning, 56, 279–304.

Kavé, G., Eyal, N., Shorek, A., & Cohen-Mansfield, J. (2008). Multilingualism and cognitive state in the oldest old. Psychology & Aging, 23(1), 70–78.

Kiran, S., & Roberts, P. (2009). Semantic feature analysis treatment in Spanish-English and French-English bilingual aphasia. Aphasiology, 24(2), 231–261.

Kiran, S. & Roberts, P. (2012). What do we know about assessing language impairment in bilingual aphasia? In M. Gitterman, M. Goral, & L.K. Obler (Eds.) Aspects of Multilingual Aphasia. Chapter 3. Bristol, UK: Multilingual Matters.

Kohnert, K., & Peterson, M. (2012). Generalization in bilingual aphasia treatment. In M. Gitterman, M. Goral, & L.K. Obler, (Eds.) Aspects of Multilingual Aphasia. Chapter 6. Bristol, UK: Multilingual Matters.

Kroll, J. F., Bobb, S. C., & Wodniecka, Z. (2006). Language selectivity is the exception, not the rule: Arguments against a fixed locus of language selection in bilingual speech. Bilingualism: Language and Cognition, 9(2), 119–135.

Laganaro, M., & Overton Venet, M. (2001). Acquired alexia in multilingual aphasia and computer-assisted treatment in both languages: issues of generalisation and transfer. Folia Phoniatrica et Logopaedica, 53(3), 135–144.

Linck, J. A., Kroll, J. F., & Sunderman, G. (2009). Losing access to the native language while immersed in a second language: evidence for the role of inhibition in second-language learning. Psychological Science, 20(12), 1507–1515. doi: PSCI2480 [pii]10.1111/j.1467-9280.2009.02480.x.

Lorenzen, B., & Murray, L. L. (2008). Bilingual Aphasia: A Theoretical and Clinical Review. American Journal of Speech-Language Pathology, 17(3), 299–317. doi: 10.1044/1058-0360(2008/026).

Marian, V., Spivey, M., & Hirsch, J. (2003). Shared and separate systems in bilingual language processing: Converging evidence from eyetracking and brain imaging. Brain and Language, 86(1), 70–82.

Miertsch, B., Meisel, J. M., & Isel, F. (2009). Non-treated languages in aphasia therapy of polyglots benefit from improvement in the treated language. Journal of Neurolinguistics, 22(2), 135-150. doi: 10.1016/j.jneuroling.2008.07.003.

Paradis, M. (2004). A neurolinguistic theory of bilingualism. Philadelphia: John Benjamins Publishing Company.

Paradis, M., & Libben, G. (1987). The assessment of bilingual aphasia. Hillsdale, NJ: Lawrence Earlbaum Associates.

Penn, C. (2007) Cultural dimensions of aphasia: Adding diversity and flexibility to the equation. In M. Ball and J. Damico (Eds.), Clinical Aphasiology: Future Directions (pp. 221–244). Hove, UK: Psychology Press.

Penn, C., Frankel, T., Watermeyer, J., & Russell, N. (2010) Executive function and conversational strategies in bilingual aphasia. Aphasiology,24, 288–308.

Perani, D., Abutalebi, J., Paulesu, E., Brambati, S., Scifo, P., Cappa, S. F., & Fazio, F. (2003). The role of age of acquisition and language usage in early, high-proficient bilinguals: An fMRI study during verbal fluency. Human Brain Mapping, 19(3), 170–182. doi: 10.1002/hbm.10110.

Roberts, P. & Kiran, S. (2007). Assessment and treatment of bilingual aphasia and bilingual anomia. In A. Ardila & E. Ramos (Eds.), Speech and Language Disorders in Bilinguals. New York: Nova Science Publishers.

Schweizer, T. A., Ware, J., Fischer, C. E., Craik, F. I., & Bialystok, E. (2011). Bilingualism as a contributor to cognitive reserve: Evidence from brain atrophy in Alzheimer's disease. Cortex. doi: S0010-9452(11)00104-3 [pii] 10.1016/j.cortex.2011.04.009.

Sebastian, R., Kiran, S., & Sandberg, C. (2012). Semantic processing in Spanish–English bilinguals with aphasia. Journal of Neurolinguistics, 25(4), 240–262. doi: 10.1016/j.jneuroling.2012.01.003.

Sebastian, R., Laird, A., & Kiran, S. (2011). Meta-analysis of neural representation of first language and second language. Applied Psycholinguistics. doi: 10.1017/S0142716411000075.

Stein, M., Federspiel, A., Koenig, T., Wirth, M., Lehmann, C., Wiest, R., ... Dierks, T. (2009). Reduced frontal activation with increasing 2nd language proficiency. Neuropsychologia, 47(13), 2712–2720. doi: S0028-3932(09)00235-8 [pii] 10.1016/j.neuropsychologia.2009.05.023.

Witford, V., & Titone, D. (2012). Second-language experience modulates first- and second-language word frequency effects: Evidence from eye movement measures of natural paragraph reading. Psychonomic Bulletin & Review, 19, 73–80.

Wong, V., & Kiran, S. (submitted). Is bilingualism a neuroprotection for bilingual individuals with aphasia? Manuscript submitted for publication.


Advertise With UsAdvertisement