Comparison of the effects of lexical retrieval and syntactic analysis on the occurrence of foreign language side effects

Using a foreign language is known to temporarily reduce the ability to think, due to the cognitive resources lost to language processing. This is called the foreign language side effect. Previous studies have shown that similarity of the structure in the foreign language used to that of the native language is associated with a smaller foreign language side effect. However, what defines a similar structure has not been clarified. This study examined whether the occurrence of foreign language side effects is due to syntactic analysis or lexical retrieval. Using a dual-task method to compare the degree of foreign language side effects between Japanese and English use among Chinese students demonstrated that the influence of lexical retrieval was larger than that of syntactic analysis.