Many studies demonstrate that detecting statistical regularities in the linguistic input plays a key role in language acquisition. In the present study, we investigated whether such learning is also involved in acquiring a morpho-syntactic structure that carries meaning. We exposed children to a miniature language in which children had to learn a grammatical marker that expressed number, and which could only be acquired on the basis of the distributional properties in the input. Results of a study with 50 kindergartners (M = 5;5) show that young children are able to infer this meaning statistically.

Many studies suggest that detecting statistical regularities in linguistic input plays a key role in language acquisition. Although statistical learning is not necessarily implicit in nature, it is often defined as learning that happens without awareness. This article investigates whether statistical learning in young children is indeed implicit, as often assumed. We trained 63 kindergarteners on a miniature language and assessed learning using a picture-matching task. We used an opt-out task to measure whether the kindergarteners possessed awareness of an acquired meaningful grammatical marker. In the opt-out paradigm, participants demonstrate awareness by expressing uncertainty through a nonverbal response: opting out. Our results are compatible with an earlier study of which the present study is a partial replication, suggesting that kindergarteners can acquire this marker from distributional properties in the input. Furthermore, although none of the children could verbalize knowledge of the structure during exit interviews, their behavior during the opt-out task indicated that they developed awareness of it.This study is part of the PhD project "Meta-linguistic Awareness in Early (Second) Language Acquisition," which is funded by the University of Amsterdam. The authors declare that they have no conflict of interest. The authors would like to thank Dirk-Jan Vet, Tiffany Boersma, Channa van Dijk, Afra Klarenbeek, Klaas Seinhorst, Joris Wolterbeek, and Joanna den Blijker for their help with constructing the experiment, three anonymous reviewers for their helpful comments, and the participating schools for their hospitality. The long time between acceptance and publication is due to issues with making the earlier study that informed the current study available.

We conducted a close replication of the seminal work by Marcus and colleagues from 1999, which showed that after a brief auditory exposure phase, 7-month-old infants were able to learn and generalize a rule to novel syllables not previously present in the exposure phase. This work became the foundation for the theoretical framework by which we assume that infants are able to learn abstract representations and generalize linguistic rules. While some extensions on the original work have shown evidence of rule learning, the outcomes are mixed, and an exact replication of Marcus et al.'s study has thus far not been reported. A recent meta-analysis by Rabagliati and colleagues brings to light that the rule-learning effect depends on stimulus type (e.g., meaningfulness, speech vs. nonspeech) and is not as robust as often assumed. In light of the theoretical importance of the issue at stake, it is appropriate and necessary to assess the replicability and robustness of Marcus et al.'s findings. Here we have undertaken a replication across four labs with a large sample of 7-month-old infants (N = 96), using the same exposure patterns (ABA and ABB), methodology (Headturn Preference Paradigm), and original stimuli. As in the original study, we tested the hypothesis that infants are able to learn abstract "algebraic" rules and apply them to novel input. Our results did not replicate the original findings: infants showed no difference in looking time between test patterns consistent or inconsistent with the familiarization pattern they were exposed to.

Research consistently shows that adults engaged in tutored acquisition benefit from explicit instruction in several linguistic domains. For preschool children, it is often assumed that such explicit instruction does not make a difference. In the present study, we investigated whether explicit instruction affected young learners in acquiring a morpho-syntactic element. A total of 103 Dutch-speaking kindergartners (M = 5;7) received training in a miniature language to learn a meaningful agreement marker. Results from a picture matching task, during which eye movements were recorded, provided no evidence that explicit instruction led to higher accuracy rates, but suggest that it did lead to earlier predictive eye movements. These data seem incompatible with the idea that explicit instruction does not make a difference when kindergartners learn a grammatical element, and tentatively suggest that explicit instruction has a different effect on explicit knowledge than on implicit knowledge in this age group.

Gifted children are described as very talented children who achieve more than their age mates in one or more domains (Steiner and Carr in Educ Psychol Rev 15(3):215–246, 2003). These children potentially share a cognitive advantage enabling them to excel in language, but also in other domains. In the present study we explored whether gifted children have a relatively advanced procedural memory. We further investigated the relation between procedural memory and complex syntactic comprehension. 25 gifted children and as many non-gifted children between ages 8 and 13 were administered a serial reaction time (SRT) task and a relative clause comprehension task. Results from the SRT task showed no significant difference between gifted children and their TD peers, whereas gifted children showed significant better comprehension of object relative clauses. No significant correlations were found between the two tasks. There was thus no evidence that gifted children excel in procedural memory. Possibly some other factor, such as meta-linguistic knowledge or a beneficial social environment, contributed to their advanced linguistic comprehension.