What Phonological Overlap Effects Reveal About the Role of Working Memory in Native and Nonnative Language Processing

The present study sheds light on effects of similarity-based interference due to phonological overlap (PO), as well as working memory (WM), during silent reading in native speakers (NS) and nonnative speakers (NNS). While prior research has mainly focused on syntactic complexity or ambiguity to gain insight into nonnative language processing and the role of WM, the effects of PO have remained poorly understood. Using multiline texts with varying degrees of PO, we examined whether increased amounts of overlap disrupt online reading and offline recall, and whether effects differ across native and nonnative groups or vary as a function of WM capacity. Results revealed that greater PO caused delays during online processing, but without impacting offline recall. Crucially, NS and NNS experienced online interference similarly, and WM modulated these effects in comparable ways across both groups. These results suggest convergence both in overt behaviour and in how underlying cognitive resources are used. Findings are discussed with respect to their implications for theories of native-nonnative language processing differences and possible directions for further research.