Examination of the Critical Period Hypothesis and Ultimate Attainment Among Spanish-English Bilinguals and English-Speaking Monolinguals

Abstract

The purpose of this investigation was to study speech recognition among Spanish-English bilingual and monolingual English-speaking individuals in two, separate yet related, studies. The first study examined phonotactic aspects and age of arrival on speech perception among three groups of bilingual individuals, thereby investigating the effects of age limitations on second language learning. The second study addressed whether fluent and proficient bilingual speakers showed equal perceptual abilities when compared to monolingual English speakers on only English gated words, thus measuring their ultimate attainment in English.

Forty-five Spanish/English fluent bilinguals with no reported speech, language, or hearing deficits participated in experiment one, whereas 30 Spanish-English fluent bilinguals and 30 monolingual English speakers with no reported speech, language, or hearing deficits participated in the second study. The Spanish-English bilingual listeners were able to differentiate words when the initial consonant cluster was voiced. In addition, CV-tense words were identified quicker (than CV-lax words) in Spanish than in English. It also appeared that exposure to two languages over a period of six or more years yielded enhanced phonotactic abilities in the second language, that is, positive language transference. Results from this study indicated that ultimate attainment of speech perception in a second language seems to occur from 9 to 15 years of age, that is, in direct contrast to when abilities should decrease according to the critical period or age limitation hypothesis. Results from the second study indicated that the Spanish-English speakers performed overall on par with their monolingual counterparts achieving ultimate attainment in speech perception. Therefore, the two studies reported here have not supported the notion of the critical period hypothesis (Lenneberg, 1967).