Unconstrained Learning Species Constraints Timing Constraints Domain Constraints

Unconstrained Learning Species Constraints Timing Constraints Domain Constraints

Taste Aversion

Konrad Lorenz

Unconstrained Learning Species Constraints Timing Constraints Domain Constraints

Categorical Speech Perception

Noam Chomsky

John is easy to please. John is eager to please.

John is easy to please. John is eager to please. It is easy to please John. *It is eager to please John.

(1)Who do you want to see? (2)Who do you want to feed the dog? (3)Who do you wanna see? (4)*Who do you wanna feed the dog?

(1)Who do you want to see? (2)Who do you want to feed the dog? (3)Who do you wanna see? (4)*Who do you wanna feed the dog? (5)You want to see who? (6)You want who to feed the dog?

(1)Who do you want to see? (2)Who do you want to feed the dog? (3)Who do you wanna see? (4)*Who do you wanna feed the dog? (5)You want to see who? (6)You want who to feed the dog? (7)Who i do you want to see t i ? (8)Who i do you want t i to feed the dog?

Unconstrained Learning Species Constraints Timing Constraints Domain Constraints

Figure 2. Some theoretical predictions of the critical period hypothesis showing disruption at predicted end of the critical period. (a)(b)

Critical Period in Second Language Learning?

Figure 1. Re-analysis of Johnson and Newport study showing discontinuity at age 20, and continued decline in adult subjects. Reported in Bialystok & Hakuta, r=-.87r=-.49

ChineseSpanish Figure 3. Self-reported English proficiency for U.S. immigrants as a function of age of arrival. Data from 1990 Census. Analysis reported in Bialystok & Hakuta, 1999.

Figure 4. Comparison of performance on selected English grammatical structures in adult and child learners. Source: Bailey, Madden & Krashen, 1974, Language Learning.

Figure 5. English proficiency development in immigrant students from a Northern California school district, separated by poverty level in schools. This is a cross-sectional sample, but all subjects included in this analysis were enrolled in this school district since Kindergarten.

Figure 6. Self-reported English proficiency for native Chinese immigrants as a function of age of arrival, separated by educational attainment. Data from 1990 Census. Analysis reported in Bialystok & Hakuta, Age of Immigration English Proficiency Some College HS Graduate Some HS <8 yrs school <5 yrs school