This paper explores the concurrent and predictive validity of the long and short forms of the Galician version of the MacArthur-Bates CDI (IDHC). Forty-two Galician-speaking children were longitudinally evaluated at age 1 ; 6, 2 ; 0 and 4 ; 0. On the first two occasions, the subjects' vocabulary and grammar skills were assessed through the IDHC. Simultaneously, lexical and grammatical measures were obtained from spontaneous speech samples. Standardized measures of general cognitive abilities (WPPSI-R) and receptive and expressive language (RDLS-III) were obtained at age 4 ; 0. Results showed high and significant levels of concurrent and short-term validity of the IDHC. Strong associations were found between lexical development at age 2 ; 0 and language scores two years later. These results coincide with those obtained with other CDI versions, and suggest that the IDHC is an effective and reliable tool.

In a number of studies, the acquisition of restrictive relative clauses (RCs) shows contrasting findings regarding comprehension and production, with the former usually delayed up to the age of five. As previously claimed in the literature, we suggest that this delay is a task artifact and we present a new procedure for the assessment of restrictive RCs. Data from three- to seven-year-old Italian children were collected and results show that children understand object RCs with preverbal subject in an adult-like manner at four years of age, but some of the three-year-old children were already above chance. Subject relatives show at ceiling performance from three years of age. We consider our results as evidence of continuity between early and adult competence grammars. Children's non-target responses are interpreted as grammatical options exploited by an immature performance system.

In the period between sole use of single words and majority use of multiword utterances, children draw from their existing productive capability and conversational input to facilitate the eventual outcome of majority use of multiword utterances. During this period, children use word combinations that are not yet mature multiword utterances, termed ‘successive single-word utterances’ (SSWUs). The language development of five children, observed in play with their mothers, was studied longitudinally across the transitional period (age 1 ; 3 to 2 ; 0). Results demonstrate a common developmental trajectory from single words to SSWUs, formed with the support of conversation, to more independent SSWUs, and finally to majority use of multiword utterances. The children varied in the extent to which they produced SSWUs and whether they first produced across-turn versus within-turn SSWUs. Possible reasons for variability and why SSWU production may be important to the development of multiword utterances are discussed.

Two studies examined whether preschool children preferred to select a moving object over stationary objects when determining the referent of a novel word. In both studies three- and four-year-olds observed three novel objects, one moving object and two stationary objects. In Study 1, children (n=44) were asked to select the object that best matched a novel word. In Study 2, children (n=45) were asked to select the object that best matched a novel fact. Results across the two studies indicated that three- and four-year-olds showed a preference for selecting the moving object and that this preference was similar for both words and facts. These results suggest that preschool children are able to use movement to determine the referent of a novel word, especially when other cues are unavailable or unhelpful, but that movement may not be uniquely helpful for word learning.

Ten mothers were observed prospectively, interacting with their infants aged 0 ; 10 in two contexts (picture description and noun description). Maternal communicative behaviours were coded for volubility, gestural production and labelling style. Verbal labelling events were categorized into three exclusive categories: label only; label plus deictic gesture; label plus iconic gesture. We evaluated the predictive relations between maternal communicative style and children's subsequent acquisition of ten target nouns. Strong relations were observed between maternal communicative style and children's acquisition of the target nouns. Further, even controlling for maternal volubility and maternal labelling, maternal use of iconic gestures predicted the timing of acquisition of nouns in comprehension. These results support the proposition that maternal gestural input facilitates linguistic development, and suggest that such facilitation may be a function of gesture type.

In this paper we report on a visual world eye-tracking experiment that investigated the differing abilities of adults and children to use referential scene information during reanalysis to overcome lexical biases during sentence processing. The results showed that adults incorporated aspects of the referential scene into their parse as soon as it became apparent that a test sentence was syntactically ambiguous, suggesting they considered the two alternative analyses in parallel. In contrast, the children appeared not to reanalyze their initial analysis, even over shorter distances than have been investigated in prior research. We argue that this reflects the children's over-reliance on bottom-up, lexical cues to interpretation. The implications for the development of parsing routines are discussed.