First Language

We explore factors affecting word learning: phonological representation, vocabulary size and the frequency with which parents name objects for their children. Infants at 16–20 months were taught two novel words using preferential looking; they showed reliable learning of these words and reliably distinguished between familiar objects with phonologically similar labels, supporting the view that phonological representation is not necessarily ‘underspecified’ at this age (Gerken, Murphy & Aslin, 1995). Infants who learnt the novel words also distinguished the objects with similar-sounding labels. However, vocabulary size was not related to word learning or segmental representation capacity, suggesting that segmental representation may help infants to learn words, but this process is not driven by vocabulary growth (Metsala, 1999). We also report a positive relationship between word learning ability and the frequency of parents’ ostensive naming.

The emergence of phonological awareness was examined in a longitudinal study. Two issues were of particular interest: (1) the relationship between phonological awareness and early language development, and (2) the relationship between theory of mind and phonological awareness. Of interest was whether early language ability at 2 years was related to phonological awareness (e.g., rhyming) at 4 years. Overall, children’s early language ability at 2 years predicted their phonological awareness at 4 years. Also of interest was the relationship between theory of mind understanding and phonological awareness. At 4 years measures of theory of mind were related to phonological awareness. Possible explanations of the link between language, theory of mind and phonological awareness are discussed.

Maternal overall verbal responsiveness to prelinguistic infants at 0;10 was analysed by categorizing responses according to their function. In addition, the predictive validity of the response categories to the child’s communicative and linguistic development at 1;0 was examined. The participants were 27 Finnish-speaking mothers and their first-born infants. The results indicated several predictive relations between the functions of maternal verbal responses and child communicative and linguistic development, while maternal overall verbal responsiveness seemed to imply aspects of verbal style only modestly. Child contributions that may account for relationships between maternal interaction and child linguistic development were also considered. The results are discussed with reference to maternal interactional sensitivity.

This study compared the sequential structure of mother-child conversation during joint picture book reading in Japanese and American dyads with children between 12 and 27 months. Although there were commonalities such as increased maternal elaborative information-asking in response to children’s labelling with children’s vocabulary growth, there were substantial differences. Japanese children produced labelling following maternal labelling more than American children, while American children produced labelling following information-asking more than Japanese children. Japanese mothers responded to children’s labelling with interpersonal utterances more than American mothers, while American mothers responded to labelling with elaborative information-asking more than Japanese mothers. Interaction in American dyads generally followed an instruction model, while interaction in Japanese dyads reflected aspects of an osmosis model.

Using a natural interactional setting, a quasi-experiment investigated stop consonants in Norwegian infant directed speech (IDS) compared with adult directed speech (ADS) in six mothers interacting with their infants at 10 points throughout six months. Voice onset time (VOT) in voiced and voiceless bilabial, alveolar and velar stops was compared between the two speech types. Results from two repeated measures analysis show longer VOTs in IDS than in ADS for alveolar and velar stops, as well as for /b/, but not for /p/. These results were stable across the six months. This suggests that stops are overspecified in speech to infants from birth until six months, maybe enhancing both auditory and visual aspects of speech in the first six months.

Should parents be encouraged to teach their hearing infants to communicate using gestural signs? Does signing in infancy advance child behaviour and development as claimed by many commercially available products for parents? To answer these questions, a review was undertaken to evaluate currently available research studies that examined the effectiveness of prelingual signing for normally developing, hearing infants. Databases, reference lists and the Internet were searched for relevant documents using a pre-determined search protocol. Seventeen reports met the review’s inclusion criteria and were retrieved and evaluated. The review failed to support claims that signing facilitates language development, due to insufficiencies in scientific methods and to equivocal results.