Dekeyser 2000
The Robustness of Critical Period Effects in Second Language Acquisition
Fundamental Difference Hypothesis
Fundamental Difference Hypothesis: Children acquire language through implicit, domain-specific mechanisms, while adults rely more on problem-solving capacities and explicit learning.
Adults at a high level of verbal analytical ability can achieve near-native competence.
Study Overview
Confirmed hypothesis with 57 adult Hungarian-speaking immigrants.
Very few adult participants scored like child arrivals on grammaticality judgment tests.
High verbal analytic ability was not a significant predictor of success for childhood second language acquisition.
Age Effects in Language Learning
Critical Period Hypothesis: Individuals past a certain age have reduced ability to learn languages compared to younger individuals.
Research has shown a gradual decline in language learning ability from ages 6-7 to 16-17.
Supports the notion that age significantly impacts language acquisition, particularly for pronunciation and grammar learning.
Literature Review
Empirical Evidence: Studies show children outperform adults in ultimate attainment despite age-related declines in learning speed.
Adults may learn more slowly but can also reach competence, although fewer can perform at a native level.
Ongoing debates exist regarding exact mechanisms and explanations for observed age effects.
Methodology of the Study
Comparison to Johnson and Newport's (1989) study to assess ultimate attainment in morphosyntax for different age groups.
Investigated various elements of grammar to look for age-related differences in acquisition.
Key Findings
Correlation Results: A strong negative correlation between age of arrival and grammaticality judgment scores was found (-.63 overall).
Structure-specific correlations show that different elements of grammar exhibit varying sensitivity to age of acquisition.
Successful acquisition among adults is primarily linked to high verbal analytical abilities.
Salient Structures and Learning
Adult learners performed better on structures that are perceptually salient or easier to detect in conversation.
Low sensitivity structures like word order errors showed less correlation with age and were learned more universally.
Conclusion
The study supports the existence of a critical period in L2 acquisition, affirming that early exposure confers a definitive advantage, particularly with implicit learning mechanisms.
Verbal aptitude plays a significant role for adults, allowing some to attain better levels of grammaticality through explicit learning.
Recommendations suggest explicit focus on form in teaching to help adult learners achieve higher competence.
The Robustness of Critical Period Effects in Second Language Acquisition
Fundamental Difference Hypothesis
The Fundamental Difference Hypothesis posits a critical distinction in how children and adults acquire languages. Specifically, it suggests that children utilize implicit mechanisms dedicated to language learning that are distinct from general cognitive processes. In contrast, adults often depend on their problem-solving abilities and explicit learning strategies. Interestingly, adults who possess a high level of verbal analytical ability can achieve near-native competence in a second language, although this is not universally the case.
Study Overview
The hypothesis was confirmed through an empirical study involving 57 adult Hungarian-speaking immigrants who were assessed on their grammaticality judgments in their second language. Out of the participants, very few were found to score similarly to child arrivals on the tests measuring grammatical competence. Furthermore, while high verbal analytical ability might seem advantageous, it was not found to be a significant predictor of success for those attempting to acquire a second language during childhood.
Age Effects in Language Learning
According to the Critical Period Hypothesis, there is a window during which individuals are more predisposed to acquiring languages. Research indicates that this ability noticeably declines after a certain age, specifically around 6-7 years, with further deterioration documented through adolescence (16-17 years). This decline underscores the importance of age as a critical factor in language acquisition, especially concerning the capacity for accurate pronunciation and grammar learning.
Literature Review
A comprehensive literature review reveals that empirical evidence consistently shows that children outperform adults in language acquisition despite the latter's potentially higher analytical skills. Adults may learn new languages at a slower pace but can still attain a functional level of competence; however, only a minority are capable of reaching native-like proficiency. There have been ongoing debates regarding the exact underlying mechanisms and reasons for the observed age effects, reflecting a complex interplay between developmental factors, cognitive abilities, and linguistic input.
Methodology of the Study
The study methodology involved a comparison to previous research, notably Johnson and Newport's (1989) work on ultimate attainment in morphosyntax across varied age groups. The current study delved into specific grammatical elements to identify age-related differences in language acquisition, enabling a thorough examination of how different aspects of grammar respond uniquely to the age of acquisition.
Key Findings
Among the key findings, a strong negative correlation was observed between the age of arrival in the country and grammaticality judgment scores, with an overall correlation coefficient of -0.63. Furthermore, analysis of structural-specific correlations revealed that different grammatical structures have varying sensitivities to the age of acquisition. Notably, successful second language acquisition for adults is generally linked to elevated verbal analytical abilities, which can enhance their learning outcomes significantly.
Salient Structures and Learning
Adult learners demonstrated superior performance in acquiring grammatical structures that are perceptually salient or easier to recognize and utilize in conversation. In contrast, structures that exhibited low sensitivity, such as word order, showed lesser correlations with age and were more uniformly learned across both age groups.
Conclusion
The findings of the study fortify the notion that a critical period exists in second language acquisition. It emphasizes that early exposure to a language confers considerable advantages, particularly in harnessing implicit learning mechanisms that are more effective in children. For adults, verbal aptitude remains a crucial factor, enabling some learners to attain higher levels of grammaticality through explicit learning methods. The research suggests educational strategies that incorporate an explicit focus on linguistic forms, aimed at facilitating higher competence among adult learners seeking to improve their second language skills.