Download - Critical Period Hypothesis
“-- the optimal time to learn a second language is between age three and five or as soon thereafter as possible, and certainly before the onset of puberty.” -- Rosalie Porter
Critical Period Hypothesis
Theoretical Components of a Critical Period?
• Beginning and end points of the period.
• Qualitative difference inside and outside the period.
• Discontinuity at the end of the period.
• Robust to environmental variation inside the period.
Johnson & Newport (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, 60-99.Pre-Puberty
2 4 6 8 10 12 14 16Age of Arrival
210
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Eng
lish
Pr o
ficie
ncy
Post-Puberty
10 20 30 40Age of Arrival
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Engl
i sh
Pr o
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r=-.87 r=-.16
Johnson & Newport, combined across age groups.
All Subjects
0 10 20 30 40Age of Arrival
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nglis
h P
rofic
ienc
y
What Kind of Theory is SES?
Hart & Risley
Hierarchical Structure of Language:Lenneberg’s Plan
Oral Proficiency
0 1 2 3 4 5 6 7GRADE
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< 25% Free Lunch25-50% Free Lunch>50% Free Lunch
Poverty Level
Reading
0 1 2 3 4 5 6 7GRADE
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Writing
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Redesignation Rate
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Figure 12. English development as a function of school poverty status. District A.
Figure 13. Norm-referenced English scores by parent educational level, District B. LEP student mean age equivalent score is represented by the colored portions of the bar; the white unshaded portion shows the expected age-equivalent for the norming population.
< High SchoolSome High SchoolHigh School or GEDBeyond High School
Parent Education
Oral Language
0 1 2 3 4 5 6GRADE
3
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5
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e Eq
uiva
lent
Sco
re
0 1 2 3 4 5 63
6
9
12
Broad English Ability
0 1 2 3 4 5 6GRADE
3
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Age
Equi
vale
nt S
core
0 1 2 3 4 5 63
6
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Figure 16. Norm-referenced English writing scores by parent educational level, District B. LEP student mean age equivalent score is represented by the colored portions of the bar; the white unshaded portion shows the expected age-equivalent for the norming population.
< High SchoolSome High SchoolHigh School or GEDBeyond High School
Parent Education
Written Expression
0 1 2 3 4 5 6GRADE
3
4
5
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Age
Equi
vale
nt S
core
0 1 2 3 4 5 63
6
9
12
Basic Writing Skills
0 1 2 3 4 5 6GRADE
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Age
Equi
vale
nt S
core
0 1 2 3 4 5 63
6
9
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Broad Written Language
0 1 2 3 4 5 6GRADE
3
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Age
Equi
vale
nt S
core
0 1 2 3 4 5 63
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Figure 13. Norm-referenced English scores by parent educational level, District B. LEP student mean age equivalent score is represented by the colored portions of the bar; the white unshaded portion shows the expected age-equivalent for the norming population.
< High SchoolSome High SchoolHigh School or GEDBeyond High School
Parent Education
Oral Language
0 1 2 3 4 5 6GRADE
3
4
5
6
7
8
9
10
11
12Ag
e Eq
uiva
lent
Sco
re
0 1 2 3 4 5 63
6
9
12
Broad English Ability
0 1 2 3 4 5 6GRADE
3
4
5
6
7
8
9
10
11
12
Age
Equi
vale
nt S
core
0 1 2 3 4 5 63
6
9
12
