Adults achieve successful coordination during conversation by using prosodic and lexicosyntactic cues to predict upcoming changes in speakership. We examined the relative weight of these linguistic cues in the prediction of upcoming turn structure by toddlers learning Dutch (Experiment 1; N = 21) and British English (Experiment 2; N = 20) and adult control participants (Dutch: N = 16; English: N = 20). We tracked participants’ anticipatory eye movements as they watched videos of dyadic puppet conversation. We controlled the prosodic and lexicosyntactic cues to turn completion for a subset of the utterances in each conversation to create four types of target utterances (fully incomplete, incomplete syntax, incomplete prosody, and fully complete). All participants (Dutch and English toddlers and adults) used both prosodic and lexicosyntactic cues to anticipate upcoming speaker changes, but weighed lexicosyntactic cues over prosodic ones when the two were pitted against each other. The results suggest that Dutch and English toddlers are already nearly adult-like in their use of prosodic and lexicosyntactic cues in anticipating upcoming turn transitions.

This study addresses the questions of whether listening to a bimodal distribution of vowels improves adult learners’ categorization of a difficult L2 vowel contrast and whether enhancing the acoustic differences between the vowels in the distribution yields better categorization performance. Spanish learners of Dutch were trained on a natural bimodal or an enhanced bimodal distribution of the Dutch vowels /ɑ/ and /aː/, with the average productions of the vowels or more extreme values as the endpoints respectively. Categorization improved for learners who listened to the enhanced distribution, which suggests that adults profit from input with properties similar to infant-directed speech.

Speech of late bilinguals has frequently been described in terms of cross-linguistic influence (CLI) from the native language (L1) to the second language (L2), but CLI from the L2 to the L1 has received relatively little attention. This article addresses L2 attainment and L1 attrition in voicing systems through measures of voice onset time (VOT) in two groups of Dutch–German late bilinguals in the Netherlands. One group comprises native speakers of Dutch and the other group comprises native speakers of German, and the two groups further differ in their degree of L2 immersion. The L1-German–L2-Dutch bilinguals (N = 23) are exposed to their L2 at home and outside the home, and the L1-Dutch–L2-German bilinguals (N = 18) are only exposed to their L2 at home. We tested L2 attainment by comparing the bilinguals’ L2 to the other bilinguals’ L1, and L1 attrition by comparing the bilinguals’ L1 to Dutch monolinguals (N = 29) and German monolinguals (N = 27). Our findings indicate that complete L2 immersion may be advantageous in L2 acquisition, but at the same time it may cause L1 phonetic attrition. We discuss how the results match the predictions made by Flege’s Speech Learning Model and explore how far bilinguals’ success in acquiring L2 VOT and maintaining L1 VOT depends on the immersion context, articulatory constraints and the risk of sounding foreign accented.

Bilingual children are often exposed to non-native speech through their parents. Yet, little is known about the relation between bilingual preschoolers’ speech production and their speech input. The present study investigated the production of voice onset time (VOT) by Dutch-German bilingual preschoolers and their sequential bilingual mothers. The findings reveal an association between maternal VOT and bilingual children’s VOT in the heritage language German as well as in the majority language Dutch. By contrast, no input-production association was observed in the VOT production of monolingual German-speaking children and monolingual Dutch-speaking children. The results of this study provide the first empirical evidence that non-native and attrited maternal speech contributes to the often-observed linguistic differences between bilingual children and their monolingual peers.