How welcoming are the neighbors? Effects of L1 neighborhood density on recognition and production of novel L2 words in adults

Abstract

This study examined how acquisition of novel words from another language (L2) is influenced by orthographic similarity with existing native language (L1) words in beginning adult learners. Native speakers of English learned to associate 80 L2 (pseudo)words with pictures depicting their meanings. Accuracy in a typing task was higher for L2 words from high-density L1 neighborhoods in the early stages of learning, but did not differ in a two-alternative forcedchoice recognition task. ERPs recorded during the final typing task revealed a late effect of L1 neighborhood that began about 700 ms after picture onset. ERPs from a language decision task before and after learning also showed differences as a function of neighborhood density. Across sessions, L2 words from high neighborhood densities elicited slower responses and larger N400s than words from low neighborhood densities. Whereas low-density neighborhood words elicited similar RTs and N400s at pretest and posttest, RTs and N400 amplitude in response to highdensity neighborhood words decreased from pretest to posttest, suggesting that L1 neighbors were less influential after learning. Together, these results demonstrate that strategic associations between novel L2 words and existing L1 neighbors scaffold learning and result in interactions among cross-language neighbors suggestive of an integrated L1-L2 lexicon.