| The present study was conducted to investigate the L2 lexical and syntactic attrition of 36 Japanese returnee children during two years after their return to Japan and to explore the factors that contributed to that attrition. Five types of measurements were used: the Peabody Picture Vocabulary Test, the Expressive Vocabulary Test, the Grade Level Vocabulary Test, the Japanese Vocabulary Test, and a storytelling task. A questionnaire and interviews were administered in order to triangulate the data.; The results of the vocabulary tests showed that the returnees' passive, active, and school vocabulary knowledge remained intact. The scores for the Japanese tests showed that they had almost doubled their L1 lexical knowledge within two years. The number of tokens and the type-token ratio in the storytelling task decreased and the narrating speed in the storytelling gradually slowed down as the frequency of false starts and repairs increased. In addition, the incorrect use of verbs and the mixing of verb tenses increased as did the use of more satellite-framed language with locative setting descriptions. This latter finding indicated that their bilingual lexicon was different from monolingual Japanese and monolingual English speakers.; In this study, age of return was the strongest factor contributing to L2 maintenance. The youngest group tended to lose the most L2 vocabulary, and the participants who were nine to 10 when they returned tended to show the greatest individual differences. Those who had to abandon studying the L2 after their return to Japan and those who were immersed in an L1 only learning environment tended to lose L2 lexical and syntactic knowledge most severely. Pre-attrition L2 proficiency, age of arrival in English-speaking countries, and length of stay abroad were moderately associated with L2 maintenance, whereas the length of incubation period and cultural identification did not have a strong relationship with the L2 maintenance of the participants in this study. The study revealed that there may be a critical threshold for language attrition around the age of nine. Theories in bilingualism, such as the retrieval failure theory and theory of cross-linguistic effects, and current research in cognitive psychology are also discussed. |
