Utterance-final position and pitch marking aid word learning in school-age children.

We investigated the effects of word order and prosody on word learning in school-age children. Third graders viewed photographs belonging to one of three semantic categories while hearing four-word nonsense utterances containing a target word. In the control condition, all words had the same pitch and, across trials, the position of the target word was varied systematically within each utterance. The only cue to word-meaning mapping was the co-occurrence of target words and referents. This cue was present in all conditions. In the Utterance-final condition, the target word always occurred in utterance-final position, and at the same fundamental frequency as all the other words of the utterance. In the Pitch peak condition, the position of the target word was varied systematically within each utterance across trials, and produced with pitch contrasts typical of infant-directed speech (IDS). In the Pitch peak + Utterance-final condition, the target word always occurred in utterance-final position, and was marked with a pitch contrast typical of IDS. Word learning occurred in all conditions except the control condition. Moreover, learning performance was significantly higher than that observed with simple co-occurrence (control condition) only for the Pitch peak + Utterance-final condition. We conclude that, for school-age children, the combination of words' utterance-final alignment and pitch enhancement boosts word learning.

Noun plural production in preschoolers with early cochlear implantation: an experimental study of Dutch and German.

OBJECTIVES: Studies investigating language skills of children after cochlear implantation usually present general measures of expressive/receptive vocabulary and grammar and rarely tackle the acquisition of specific language phenomena (word classes, grammatical constructions, word forms, etc.). Furthermore, research is largely restricted to children acquiring English. Cross-linguistic comparisons among children acquiring different languages are almost inexistent. The present study targets the acquisition of noun plurals (e.g., dogs, balls) by Dutch- and German-speaking children implanted before their second birthday. Given its structural complexity and irregularity, noun plural formation is a good indicator of grammatical proficiency in children at risk for a developmental delay. METHODS: The study sample consisted of 14 cochlear-implanted (CI) children (M=55 months of age), 80 age-matched normally hearing (NH) controls, and 40 normally hearing controls matched by Hearing Age (HA). The children were administered an elicitation task in which they had to provide plural forms to a set of singular nouns. The analysis focussed on the following variables: Hearing status (CI, NH), Language (Dutch, German), and Suffix Predictability/Stem Transparency of the plural words. RESULTS: There was no significant difference between children with CI and their NH peers in correct plural production. In both child groups, plural responses followed the predicted pattern of Suffix Predictability/Stem Transparency. However, children with CI significantly more frequently replied to the test item with a recast of the singular noun instead of the plural, and the probability of these responses increased with later age of CI implantation. Furthermore, Dutch-speaking children showed an overall better performance than German-speaking children. CONCLUSIONS: The findings suggest that after 3 years of implant use, preschoolers with early cochlear implantation show age-appropriate patterns of noun plural formation, but still have to catch up with respect to associating a particular singular with its plural form.

How children perceive fractals: hierarchical self-similarity and cognitive development.

The ability to understand and generate hierarchical structures is a crucial component of human cognition, available in language, music, mathematics and problem solving. Recursion is a particularly useful mechanism for generating complex hierarchies by means of self-embedding rules. In the visual domain, fractals are recursive structures in which simple transformation rules generate hierarchies of infinite depth. Research on how children acquire these rules can provide valuable insight into the cognitive requirements and learning constraints of recursion. Here, we used fractals to investigate the acquisition of recursion in the visual domain, and probed for correlations with grammar comprehension and general intelligence. We compared second (n=26) and fourth graders (n=26) in their ability to represent two types of rules for generating hierarchical structures: Recursive rules, on the one hand, which generate new hierarchical levels; and iterative rules, on the other hand, which merely insert items within hierarchies without generating new levels. We found that the majority of fourth graders, but not second graders, were able to represent both recursive and iterative rules. This difference was partially accounted by second graders' impairment in detecting hierarchical mistakes, and correlated with between-grade differences in grammar comprehension tasks. Empirically, recursion and iteration also differed in at least one crucial aspect: While the ability to learn recursive rules seemed to depend on the previous acquisition of simple iterative representations, the opposite was not true, i.e., children were able to acquire iterative rules before they acquired recursive representations. These results suggest that the acquisition of recursion in vision follows learning constraints similar to the acquisition of recursion in language, and that both domains share cognitive resources involved in hierarchical processing.

Early noun plurals in German: regularity, productivity or default?

The acquisition of German plurals has been the focus of controversy in the last decade. In this paper we claim that degree of productivity (i.e. the capacity of nouns to form potential plurals) plays a key role in determining pace of acquisition. A plural elicitation task was administered to 84 Viennese German-speaking children aged 2;6 to 6;0. Analyses of correct responses showed that the highest scores were obtained with -e plurals, followed by the plural markers -e + U, -er + U, -s and -(e)n. The lowest score was observed for pure Umlaut (U) plurals. Analyses suggested an impact of productivity on the number of correct scores: fully productive and productive plural patterns obtained higher correct scores than weakly productive and non-productive ones. The results of the study support our productivity scale and are compatible both with single-route models and with a race-model variant of the dual-route view.