The relationship between working memory capacity, bilingualism, and ambiguous relative clause attachment

Working memory (WM) capacity has been shown to influence how readers resolve syntactic ambiguities. Building on the work of Swets et al. (2007, Journal of Experimental Psychology: General, 136[1], 64–81), the goal of the present study was to assess the effects of working memory and language proficiency on first language (L1) relative clause attachment decisions across three different language samples: English monolinguals, L1–L2 Spanish–English heritage bilinguals, and L1–L2 Mandarin–English bilinguals. Binomial logistic regression analyses demonstrated that low WM span is associated with a preference to attach ambiguous relative clauses higher in the syntactic structure, as reported by Swets et al. (2007), and contrary to a recency strategy. We also observed that proficiency in L1 and L2 have little effect, suggesting that relative clause attachment preferences primarily reflect the properties of the language and the working memory capacity of the comprehender.