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Language Control in the Bilingual Brain Crinion et al. (2006) Ema Salja

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Page 1: Background  Bilinguals can voluntarily control which language is used  Distinguish language heard/read  Which language speech is to be produced in

Language Control in the Bilingual Brain

Crinion et al. (2006)

Ema Salja

Page 2: Background  Bilinguals can voluntarily control which language is used  Distinguish language heard/read  Which language speech is to be produced in

Background Bilinguals can voluntarily control which

language is used Distinguish language heard/read Which language speech is to be produced in Inhibition of non-selected language

Proficient bilinguals activate same brain regions regardless of which language presented or produced (Abutalebi, & Perani, 2005).

Neural circuits for different languages are overlapping/ interconnected but don’t indicate how brain controls language in use

Page 3: Background  Bilinguals can voluntarily control which language is used  Distinguish language heard/read  Which language speech is to be produced in

Question & Hypothesis

What brain areas are responsible for language control?

DV: brain activation (fMRI & PET)

IV: Language of target Target & prime

semantics Target & prime language

Hypothesis? They didn’t

really have one…

Page 4: Background  Bilinguals can voluntarily control which language is used  Distinguish language heard/read  Which language speech is to be produced in

Methods Subjects (German-English & Japanese-English

bilinguals)visually shown pairs of words (i.e. trout-SALMON) in sequence Language Pairs semantically similar/different Target and prime were in same/different

language

Ignore first word (prime) & make decision based on meaning of second word (target) Time between prime & target optimized for

priming, but not long enough to predict target (250 ms)

Task presented while subjects being scanned (fMRI & PET)

Page 5: Background  Bilinguals can voluntarily control which language is used  Distinguish language heard/read  Which language speech is to be produced in

Results

No significant effect of target language on accuracy

Some variance in visual cortex activation

Semantic priming in left ventral anterior temporal lobe is language-independent

Language-dependent semantic priming only in left caudate (LC) Reduced activation

when semantically similar prime & target in same language

Page 6: Background  Bilinguals can voluntarily control which language is used  Distinguish language heard/read  Which language speech is to be produced in

Discussion Suggest that LC plays a role in

sensing change in language OR word semantics

LC seems to function for language control Neuropsychological study on

particular trilingual patient with white matter lesions around LC Retained comprehension in all

3 Involuntarily switched between

languages during production tasks

Page 7: Background  Bilinguals can voluntarily control which language is used  Distinguish language heard/read  Which language speech is to be produced in

Limitations & Next Step

Limitations

Characters/word varied between languages

Sample size/bilingual group (~ 10-15)

Tested only German-English & Japanese-English bilinguals

Next Step

Determine adjacent & connecting pathways

Test other bilingual groups

Check effect of varying proficiencies (one language more dominant then other)

Page 8: Background  Bilinguals can voluntarily control which language is used  Distinguish language heard/read  Which language speech is to be produced in

Final Note

Strengths Interesting Topic

Tested bilinguals from completely separate linguistic families

Equivalent linguistic proficiencies

Weaknesses Difficult to read

No clear question, hypothesis or variables

Not enough information or detail regarding subjects & procedures

Page 9: Background  Bilinguals can voluntarily control which language is used  Distinguish language heard/read  Which language speech is to be produced in

References

Abutalebi, J., & Perani, D. (2005). the neural basis of first and second language processing. Current Opinion in Neurobiology, 15, 202-206.

Aso, T., Crinion, J., Fukuyama, H., Green, D. W., Grogan, A., Hanakawa, T.,…Urayama, S. (2006). Language control in the bilingual brain. Science, 312, 1537-1540. doi: 10.1126/science.1127761.