Hasan Haqqani Zadeh - Ph. D in TEFL, North Khorasan Farahngian University, Bojnurd, Iran
Amirreza Houshmand - TEFL Student, Farhangian University, Imam Mohamad Baqer Branch, Bojnurd, Iran
Mohamad Naderi Bavanlu - TEFL Student, Farhangian University, Imam Mohamad Baqer Branch, Bojnurd, Iran
Seyed Shahab-Al-Din Musavi - TEFL Student, Farhangian University, Imam Mohamad Baqer Branch, Bojnurd, Iran

Aims and objectives: The goal of the this study was to examine the effects of age of acquisition on verbal working memory (WM) in bilinguals. In light of previous studies that have found a bilingual advantage on non-verbal WM and less consistently on verbal WM, we included participants with native-like second language (L2) proficiency who hadbenefited from several years of dual language use and who did not differ from the monolinguals in terms of socioeconomic status in order to control for proficiency. Very few studies have looked at bilinguals’ performance on measures of both verbal and non-verbal memory, making it difficult to know how bilingualism influences both types ofabilities in the same participants. Therefore, we also compared the groups on non-verbal WM. Methodology: Simultaneous bilingual, early successive bilinguals, and late successive bilinguals were compared with monolingual English speakers. All bilingual participants were selected using three different criteria: self-assessment ratings of English abilities, ratings of nativelikeness by a native English speaker, and scores on a L2 Cloze test. The groups did not differ significantly with respect to their L2 proficiency, or on measures of general cognitive ability. Data and analysis: Fifteen simultaneous bilinguals were compared with 15 early successive bilinguals and 15 late successive bilinguals who acquired English between 4–6 years of age and 7–15 years of age, respectively. The bilinguals were compared with 15 English-speaking monolinguals. Participants were compared using verbal and nonverbal short-term memory and WM tests Findings: All bilingual groups performed significantly better than the monolinguals on tests of verbal and non-verbal WM, thus supporting a bilingual advantage. The early and late successive bilinguals scored significantly lower than the simultaneous bilinguals, suggesting an age of acquisition effect among the bilinguals.

Bilingualism, age of acquisition, executive functions, memory, cognition