Degree of bilingualism modifies executive control in Hispanic children in the USA.

Past studies examining the cognitive function of bilingual school-aged children have pointed to enhancements in areas of executive control relative to age-matched monolingual children. The majority of these studies has tested children from a middle-class background and compared performance of bilinguals as a discrete group against monolinguals. The objective of the present study was to determine if cognitive enhancement from bilingualism is sensitive to the child's degree of bilingualism in a sample of eight- and nine-year old Spanish-English bilingual children of low socioeconomic status. The results showed that the more balanced the children were in their language skills, the better they performed on non-verbal tasks of cognitive function. These results support an additive view of bilingualism, where more balanced proficiency in two languages is associated with more enhanced cognitive function, regardless of socioeconomic background.

Effects of racial diversity on complex thinking in college students.

An experiment varying the racial (Black, White) and opinion composition in small-group discussions was conducted with college students (N = 357) at three universities to test for effects on the perceived novelty of group members' contributions to discussion and on participants' integrative complexity. Results showed that racial and opinion minorities were both perceived as contributing to novelty. Generally positive effects on integrative complexity were found when the groups had racial- and opinion-minority members and when members reported having racially diverse friends and classmates. The findings are discussed in the context of social psychological theories of minority influence and social policy implications for affirmative action. The research supports claims about the educational significance of race in higher education, as well as the complexity of the interaction of racial diversity with contextual and individual factors.

Critical evidence: a test of the critical-period hypothesis for second-language acquisition.

The critical-period hypothesis for second-language acquisition was tested on data from the 1990 U.S. Census using responses from 2.3 million immigrants with Spanish or Chinese language backgrounds. The analyses tested a key prediction of the hypothesis, namely, that the line regressing second-language attainment on age of immigration would be markedly different on either side of the critical-age point. Predictions tested were that there would be a difference in slope, a difference in the mean while controlling for slope, or both. The results showed large linear effects for level of education and for age of immigration, but a negligible amount of additional variance was accounted for when the parameters for difference in slope and difference in means were estimated. Thus, the pattern of decline in second-language acquisition failed to produce the discontinuity that is an essential hallmark of a critical period.