This article presents the adaptation of the MacArthur Communicative Development Inventory (CDI; Fenson et al., 1993, "Guide and technical manual for the MacArthur Communicative Development Inventories." San Diego, CA: Singular Press; Fenson et al. 1994, Variability in early communicative development. "Monographs of the Society for…

Background and Aims: The purpose of this exploratory study was to expand existing literature on prelinguistic vocalizations by reporting results of the first home-based longitudinal study examining a wide variety of behaviors and characteristics, including early vocalizations, across infants at low and elevated risk of autism spectrum disorder…

The current study examined how mothers' production of four types of internal state words at multiple ages across the second year in a free play context was related to their infants' acquisition of those words. Twenty-nine mother-infant dyads were videotaped for 18 minutes during free play when infants were 13 and 17 months old. Mothers' total and…

Around their first birthdays, infants begin to point, walk, and talk. These abilities are appreciable both by researchers with strictly standardized criteria and caregivers with more relaxed notions of what each of these skills entails. Here, we compare the onsets of these skills and links among them across two data collection methods: observation…

Adult humans process communicative interactions by recognizing that information is being communicated through speech (linguistic ability) and simultaneously evaluating how to respond appropriately (social-pragmatic ability). These abilities may originate in infancy. Infants understand how speech communicates in social interactions, helping them…

This article describes the European Portuguese MacArthur-Bates Communicative Development Inventories short forms, the first published instruments for the assessment of language development in EP-learning infants and toddlers. Normative data from the EP population are presented, focusing on developmental trends for vocabulary learning, production…

The Spanish-language MacArthur-Bates Communicative Development Inventories (S-CDIs) are well-established parent report tools for assessing the language development of Spanish-speaking children under 3 years. Here, we introduce the short-form versions of the S-CDIs (SFI and SFII), offered as alternatives to the long forms for screening purposes or…

Two experiments examined infants' ability to form a spatial category when habituated to few (only 2) or many (6) exemplars of a spatial relation. Sixty-four infants of 10 months and 64 infants of 14 months were habituated to dynamic events in which a toy was placed in a consistent spatial relation ("in" or "on") to a referent…

This article presents results from a large population-based study of early communicative development in Norwegian children using an adaptation of the MacArthur-Bates Communicative Development Inventories, comprising 6574 children between 8 and 36 months. Data were collected via the Internet. In accordance with similar studies from other languages,…

This research revealed both similarities and striking differences in early language proficiency among infants from a broad range of advantaged and disadvantaged families. English-learning infants ("n" = 48) were followed longitudinally from 18 to 24 months, using real-time measures of spoken language processing. The first goal was to…

Several studies have demonstrated that children's gender and parental education exert a significant, but not equal, effect on toddler language development at different ages. This study determined the effect of children's gender and parental education on the verbal competence of toddlers between 16 and 30 months. The sample included 953 Slovenian…

Vocabulary development of three children, aged 1;6 to 1;8, who had not yet begun to evidence a vocabulary spurt was followed to determine if these children would eventually have a vocabulary spurt. Results of the study are discussed in the context of the argument that a substantial proportion of children never evidence a vocabulary spurt. (JL)

A longitudinal sample of 226 infants were tested monthly on habituation and novelty preference tasks, augmented with simultaneous heart rate recording from 3 to 9 months of age. Infants were then administered the Bayley Scales of Infant Development II (BSID) and MacArthur Communicative Development Inventory (MCDI) at 12, 18, and 24 months. Prior…