A presentation of Pallier et al. 2003

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Aarhus Brain and Cognition Group,

• A presentation of Pallier et al. (2003)
• Cerebral cortex, 13, 155-161,
• Brain imaging of language plasticity in adopted
  adults Can a second language replace the first?
• Anders Højen May 12, 2005

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Background

• The later a second language (L2) is learned, the
  less native-like learners perform in their L2
• Could be caused by a gradual loss of neural
  plasticity (modified critical period hypothesis)
• Or as a result of native language (L1) learning
  itself (Flege!? Perhaps rather Kuhls Native
  Language Magnet theory)

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Purpose

• Test if L1 exposure leaves enduring traces in L1
  neural circuits
• Study adults who were adopted as young children
• fMRI and behavioral tests

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Methods

• Subjects
• Native Korean adults (2 f, 6 m) adopted by French
  families at age 2-8.
• Matched native French control group

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Methods

• Stimuli and procedure
• Listen to Korean, Japanese, Polish, Swedish and
  Wolof samples. For each language, Ss had to rate
  how sure they were it was Korean
• Choose which of two Korean one was the Korean
  translation of a given French word
• fMRIs while listening to Korean, Japanese,
  French, or Polish match excerpt to language

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Results behavioral tests

• No difference between adoptees and French
  controls for
• Rating of language samples
• Word translation
• Match excerpt to language sample

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Results behavioral tests
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Results fMRI

• French stimuli (Polish or Japanese baseline)
  Activation of same areas, but to a different
  extent in adoptees and controls
• Korean stimuli (Polish baseline)
  No extra activation in adoptees (but for two
  regions in French controls!)
• No difference between groups or languages in the
  Korean-Japanese or Japanese-Polish analyses

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Results fMRI

• French-Korean or Korean-French analyses No
  between-group difference in relative activation

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Summary

• No between-group differences in behavioral tests
• Virtually no difference in fMRI tests

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Palliers conclusion

• Crystalization hypothesis
• Due to maturational and/or experiential factors
  the window of brain plasticity gradually closes
  (e.g., Flege)
• Not supported

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Palliers Conclusion

• Palliers alternative, Interference
  hypothesis
• Differences between native and nonnative
  speakers are not due to a loss of plasticity, but
  to interaction between the L1 and the L2
  subsystems
• BUT

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Pallier et al. 1997 !!!

• Our study demonstrates a striking lack of
  behavioral plasticity early and extensive
  exposure to a second language is not sufficient
  to attain the ultimate phonological competence of
  native speakers.
• This influential study is not commented on!

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Palliers interference hypothesis is essentially
identical to Fleges Speech Learning Model

• The mechanisms and processes used in learning the
  L1 sound system, including category formation,
  remain intact over the life span and can be
  applied to L2 learning (Flege, 1995)
• Interaction between the native and second
  language phonetic subsystems (Flege et al.,
  2003)

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Anyways

• The study is extremely important in showing that
  an L1 can fade away when not used (More
  behavioral evidence by Ventureyra et al., 2004)
• Virtually no difference in cortical activation
  between adoptees and L1 French controls when
  processing French

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References

• Flege, J. E. (1995). "Second language speech
  learning Theory, findings, and problems," in
  Speech perception and linguistic experience
  Issues in cross-language research, edited by W.
  Strange (York Press, Timonium, MD), pp. 233-277.
• Flege, J. E., Schirru, C., and MacKay, I. R. A.
  (2003). "Interaction between the native and
  second language phonetic subsystems," Speech
  Communication 40, 467-491.
• Pallier, C., Bosch, L., and Sebastián-Gallés, N.
  (1997). "A limit on behavioral plasticity in
  speech perception," Cognition 64, B9-B17.
• Pallier, C., Dahaene, S., Poline, J. B., LeBihan,
  D., Argenti, A. M., Dupoux, E., and Mehler, J.
  (2003). "Brain imaging of language plasticity in
  adopted adults Can a second language replace the
  first?," Cereb. Cortex 13, 155-161.