The facilitative role of lexical frequency in adults' initial L2 syntax acquisition

High frequency words are more strongly activated than low frequency words, which causes the former to be processed faster than the latter. In the MOGUL framework, the higher the activation of a word is during processing, the higher the activation of the structure containing it is and the greater the learning of the structure resulting from processing is. This study explores whether differences in lexical frequency facilitate adults' acquisition of L2 structures and whether and how this facilitation is modulated by cross-linguistic syntactic similarity. In a structure-search task, two groups of 44 Spanish natives without knowledge of Galician were exposed to a Spanish-Galician similar structure and a Spanish-Galician dissimilar one using Galician verbs cognate with Spanish high or low frequency verbs. Then, a Grammaticality Judgement Task showed that the two structures were learnt. Importantly, the stronger activation of high frequency verbs compared to low frequency verbs facilitated the acquisition of the cross-linguistically dissimilar structure, but not of the cross-linguistically similar structure, which could be processed using an L1 structure. These findings broaden our understanding of the facilitation exerted by lexical processing in initial L2 syntax acquisition and could have pedagogical implications.