Abstract
The aim of this study was to investigate the effect of the age of second language acquisition on auditory binaural and temporal processing in three groups of early and late Persian-English bilingual and Persian monolingual children. The sample consisted of 63 subjects aged between 9 and 13 years, divided into: 21 monolingual, 21 early bilingual and 21 late bilingual children. The individuals were underwent to the Dichotic digits (DD), Pitch Pattern Sequence (PPS), Duration Pattern Sequence (DPS) and gaps in noise (GIN) tests. The results showed that the scores of dichotic digits, frequency and duration pattern tests were different between the three groups. These scores were better in early bilingual in comparison to other groups. There was no difference in the scores of the mentioned tests between the late bilingual and monolingual groups. There was no significant difference between the GIN results in the three study groups. predictive variables include Binaural Proficiency (BP), Age of Acquisition (AoA) of English language, Time Period of Learning (TPL) English language are the determining factors of the dichotic digit and the frequency and duration pattern tests. Learning a second language before the age of six has a positive effect on dichotic and temporal pattern processing. In addition, lower AoA, more proficiency in the second language, and the longer the duration of receiving the second language training are related to better dichotic and temporal pattern processing.