Critical Period

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• Critical Period
• The Critical Period Hypothesis
• There is a biological period during which
  language can be acquired easily, perfectly, and
  without an accent after this time, it is
  difficult, if not impossible, to learn language
  perfectly and without an accent.

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• Critical Period First Language
• Victor
• feral child, France, 1799, 12 years old
• no language, receptive to forest sounds
• Dr. Jean Itard, 5 years tutoring Victor learned
  lait and O Dieu! but never used them
  communicatively.
• Itard, J. (1932). The wild boy of Aveyron. NY
  Century.
• LEnfant Sauvage (the Wild Child), Francois
  Truffaut, 1970

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• Critical Period First Language
• Genie
• 1970, California, 13.5 years old, isolated since
  20 months (tied to bed by psychotic father),
  beaten if she vocalized, father spoke only in
  grunts.
• After 5 years of education, she could speak,
  though slowly, and with greater-than-normal gaps
  between hearing and comprehension, overuse of
  formulaic languagerecognizably different from
  native speakers.
• Rymer, R. (1993). Genie An abused childs flight
  from silence. London Michael Joseph.

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• Critical Period First Language
• Deaf Children
• Born to hearing parents, sometimes deprived of
  exposure to sign language in infancy.
• Newport, E. (1990). Maturational constraints on
  language learning. Cognitive Science ,14, 1128.
• group 1 exposure since birth
• group 2 exposure since school (age 4 6)
• group 3 exposure after age 12.
• Results showed decreasing grammaticality in ASL
  among the three groups.

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• Critical Period Second Language
• 1. Patkowski, M. (1980). The sensitive period for
  the acquisition of syntax in a second language.
  Language Learning, 30, 449472.
• SL informants group 1 began learning English
  before puberty group 2 after puberty.
• Speech recorded, transcribed, rated by native
  speakers on a scale from 0 (no knowledge of
  English) to 5 (educated native speaker).
• note that this eliminates the phonological
  variable (i.e., accent).

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• Critical Period Second Language
• 1. Patkowski, M. (1980). The sensitive period for
  the acquisition of syntax in a second language.
  Language Learning, 30, 449472.

What does the irregular shape of the distribution
mean? Nearly everyone rated like a native
speaker success in SLA is inevitable before
puberty.
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• Critical Period Second Language
• 1. Patkowski, M. (1980). The sensitive period for
  the acquisition of syntax in a second language.
  Language Learning, 30, 449472.

What does the normal shape of the distribution
mean? Results vary widely some do well, others
do not success is not inevitable after the
puberty.
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• Critical Period Second Language
• Johnson, J. Newport, E. (1989). Critical period
  effects in second language learning The
  influence of maturational state on the
  acquisition of English as a second language.
  Cognitive Psychology, 21, 6099.
• Chinese and Korean subjects with varying ages of
  arrival in the United States all highly educated
  (students and professors at universities).
• Grammaticality judgment test wide range of
  morphology / syntax rules, multiple sentences,
  some correct, some incorrect. Subjects make
  judgments about correctness.

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• Critical Period Second Language
• Johnson, J. Newport, E. (1989). Critical period
  effects in second language learning. Cognitive
  Psychology, 21, 6099.

What does r -0.87 mean? What does this
correlation suggest? A pattern re success in SLA
(linearity), even before puberty.
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• Critical Period Second Language
• Johnson, J. Newport, E. (1989). Critical period
  effects in second language learning. Cognitive
  Psychology, 21, 6099.

What does r -0.16 mean? What does lack of
correlation suggest? Learners have widely varying
degrees of success in SLA after puberty.
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• Critical Period Second Language
• DeKeyser, R. (2000). The robustness of critical
  period effects in second language acquisition.
  Studies in Second Language Acquisition, 22,
  499533.
• This study builds on and extends Johnson and
  Newport (1989), both methodologically and
  conceptually.

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• Critical Period DeKeyser (2000)
• Questions for groups
• What variable does DeKeyser add to JN, and how
  is it measured?
• Why does DeKeyser add the variable?
• How does DeKeyser modify JNs instrument for
  data collection, and why?
• What changes does DeKeyser make in the group from
  which data is collected, and why?
• How are DeKeysers age-related results similar
  to, and different from, JNs (Question 1)?
• What does the addition of the variable (point 2)
  allow him to explain relative to Question 2?

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• Critical Period DeKeyser Questions
• What variable does DeKeyser add to JN, and how
  is it measured?
• Aptitude, or analytic verbal ability (p. 506).
  Measured by the Modern Language Aptitude Test.
  Participants completed the MLAT test (20, 5-way,
  multiple-choice questions) after the other
  instrument and the background questionnaire.

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• Critical Period DeKeyser Questions
• Why does DeKeyser add the variable?
• In an effort to explain the exceptions in
  previous studies and observations people or
  participants who are very successful with
  language learning, but began the process of
  language learning as adults.
• Exceptions may explain the right tail in
  Patkowskis distribution

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• Critical Period DeKeyser Questions
• Why does DeKeyser add the variable?
• In an effort to explain the exceptions in
  previous studies and observations people or
  participants who are very successful with
  language learning, but began the process of
  language learning as adults.
• Or the outliers in JN

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• Critical Period DeKeyser Questions
• Why does DeKeyser add the variable?
• In an effort to explain the exceptions in
  previous studies and observations people or
  participants who are very successful with
  language learning, but began the process of
  language learning as adults.
• Or the impressionistic data in other studies
  (Coppieters, 1987) or the partial overlap of the
  native and nonnative distributions in Birdsong
  (1992) (p. 507).

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• Critical Period DeKeyser Questions
• How does DeKeyser modify JNs instrument for
  data collection, and why?
• Grammaticality judgment task instrument shortened
  from 276 to 200 items / sentences. Original test
  may have been too long for the participants to
  concentrate on every item (p. 502).

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• Critical Period DeKeyser Questions
• What changes does DeKeyser make in the group from
  which data is collected, and why?
• Native speakers of Hungarian, in and around
  Pittsburgh
• Long period of residence (10 years), to
  eliminate possible confusion between age of
  arrival and age of test taking in JN, where
  period of residence was only minimum of 5 years.
• Wide range in age of arrival and socioeconomic
  status. Why socioeconomic status?
• a first approximation of verbal ability i.e.,
  aptitude (p. 508).

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• Critical Period DeKeyser Questions

5. How are DeKeysers results similar to, and
different from, JNs results (Question 1)? R
-0.63
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• Critical Period DeKeyser Questions
• How are DeKeysers results similar to JNs?
• The correlation between age of arrival and test
  score is remarkably similar.
• What does this suggest?
• An age-related effect in SLA.

r -0.77 r -0.63
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• Critical Period DeKeyser Questions
• How are DeKeysers results different than JN?
• Whereas JN found a strong correlation between
  age of arrival and test score before puberty (r
  -0.87), DeKeyser did not (r -0.26).
• What does this suggest?

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JN r -0.87
DeKeyser r -0.26
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• Critical Period DeKeyser Questions
• How are DeKeysers results different than JN?
• It might betray a lack of disruption in English
  proficiency between early and later arrivals the
  uninterrupted downward linear trend might fail to
  illustrate the end of Critical Period.

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JN r -0.87
DeKeyser r -0.26
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• Critical Period DeKeyser Questions
• How are DeKeysers results different than JN?
• Or, it might illustrate the different shapes of
  the distribution before and after puberty
  which, while different from JN, nevertheless
  suggest a disruption signaling the end of the CP.

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JN r -0.87
DeKeyser r -0.26
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• Critical Period DeKeyser Questions
• How are DeKeysers results different than JN?
• On the other hand, DeKeysers results did show a
  difference between early and late arrivals
  relative to aptitude.
• Early arrivals showed no correlation between
  English proficiency and aptitude (r 0.07, ns).
• Late arrivals showed a moderate correlation (r
  0.33 p lt .05).
• What does this mean?
• That early arrivals did not need above average
  aptitude to achieve high English proficiency.
  Something else facilitated their success, maybe
  Critical Period effects.

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• Critical Period DeKeyser Questions

6. What does the addition of the aptitude
variable allow him to explain relative to
Question 2? The exceptions to CP predications
i.e., adult learners who achieve very high
levels of SL proficiency.
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• Critical Period DeKeyser Questions

Among those who started acquiring English
after age 16 but obtained a high score on the
test (over 175), all but one had an aptitude
score of 6 or above (p. 514). Only the adults
with above average aptitude eventually became
near native (p. 515).
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• Critical Period Explanations
• Neurological Explanation
• Brain lateralization refers to the separation of
  brain functions into right and left. Language is
  controlled by the logical / analytical left side.
• Lateralization is completed at around the time of
  puberty. Before lateralization, the brain is
  plastic, meaning that it is still developing
  and dynamic, and that brain functions and paths
  are not yet firm.
• Some researchers have suggested that
  lateralization constrains the ability to learn
  language that it constitutes the close of the
  Critical Period.

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• Critical Period Explanations
• 2. Cognitive Explanation
• Cf. Piagets theory of child development.
  Children advance from the Concrete operational
  stage (ages 7 to 11), wherein they begin to think
  logically about concrete events, to the Formal
  operational stage (age 11 ff.) wherein they
  develop abstract reasoning ability.
• Researchers have suggested that there is a
  relationship between Piagets concrete and formal
  stages and the ability to learn language.
  Gaining the ability to think abstractly, which of
  course means we approach tasks like language
  learning differently, the Critical Period closes.

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• Critical Period Explanations
• 3. Psychomotor Explanation
• The Critical Period may be related to our
  physical development. More specifically, it may
  close with when we have completed the process of
  learning how to form the sounds of our native
  language.
• African clicks?

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• Critical Period Explanations
• Affective Explanation
• At a certain point in their development, children
  become conscious of themselves relative to other
  people. This consciousness affects their
  confidence, degree of extro / introversion,
  attitudes, inhibitions, and other affective
  aspects (i.e., emotions and feelings).
• Researchers relate the CP to this development of
  affective consciousness. Before it, children are
  open and uninhibited, and they learn language
  easily and perfectly. After it after the CP
  closes their emotions inhibit language learning
  and render the result imperfect.

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• Critical Period Explanations
• 5. Socio-Biological Explanation
• Some scholars suggest a relationship between the
  process of sexual maturation and our ability to
  learn language.
• At the point of sexual maturation (puberty), we
  lose the ability to learn a new language without
  an accent. The accent that we do acquire marks
  us for potential mates, making us un/ attractive
  to them, thereby maintaining the purity of the
  gene pool for future generations.
• think hominids, race / ethnicity, social class
  http//www.youtube.com/watch?v_vF9g37FCmkfeature
  autoplaylistPL037415A3348CAFC5lfresults_main
  playnext2

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• Critical Period Hakuta, Bialystok, Wiley
• Recall how DeKeysers results differed from
  JNs.
• The uninterrupted downward linear trend perhaps
  failed to illustrate the end of CP. If the CP
  does not end, then is there such a thing as a
  critical period?
• This is exactly what Hakuta et al. wonder.

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JN r -0.87
DeKeyser r -0.26