Investigating the Effect of Working Memory Capacity on English Vocabulary and Grammar Learning in Inductive and Deductive Instructional Methods

Working memory as a cognitive system is considered as one of the sources of individual differences in second language learning by many researchers. In order to examine the relationship between the capacity of two components of working memory (as one of the sources of individual differences in learning) and learning English vocabulary and grammar (as basic components in learning a second language), and also to explore the effect of instructional method as an effective variable along with working memory capacity, a convenience sampling method research was conducted. Subjects of this study were 74 female language learners selected from children between 9-12years old. These learners were at the beginner level in terms of English language proficiency. In order to determine the phonological loop capacity, non-word repetition test and digit recall test were used and, counting recall test and backward digit recall test were employed to determine central executive capacity. Based on the scores of these tests, language learners were divided into two homogeneous groups. The first group received inductive instruction and the second group underwent deductive instruction. Linear regression and two sample independent t-test were used for data analysis. The results indicated that both the phonological loop capacity and the central executive capacity had a significant effect on English vocabulary and grammar learning. Moreover, deductive teaching method significantly leads to better results in terms of grammar learning compared to the inductive teaching method.