Investigates differences in the language learning environments of six twin pairs and 12 singleton toddlers (all firstborn) with special reference to pragamatic factors that might be expected to differ in dyadic and triadic interactive situations. (HOD)

Investigated birth-order differences in children's early vocabulary development. Compared the composition and age of acquisition of the first 50 and 100 words of 9 firstborns and their younger siblings, using a longitudinal maternal diary methodology. A small but significant birth-order effect was found for the age at which the 50-word milestone…

This study, involving 67 children (ages 2 to 60 months) with motor delays, found that the Battelle Developmental Inventory (BDI) possessed moderate to high levels of concurrent validity with appropriate subtests from the Vineland Adaptive Behavior Scales and the Bayley Scales of Infant Development. (Author/JDD)

This study examines the processes underlying vocabulary acquisition, i.e., how new words are learned, in children with Williams Syndrome, a rare neurodevelopmental disorder. A Williams Syndrome group was compared to groups of normal controls in the range 3-9 years in four different experiments testing for constraints on word learning. (Author/JL)

Compared performance of infants with autism, developmental delays, or normal development on a prospective screening instrument for autism. Found that 20-month-olds with autism lacked social gaze in empathy and joint attention tasks. Infants with autism or developmental delays demonstrated functional play. Few produced spontaneous pretend play.…

Tested whether 2- to 4-year olds could reason with incongruent syllogisms when encouraged to use their imagination. Randomly assigned 2-, 3-, and 4-year olds to one of four conditions (no cue, word cue, fantasy planet, or imagery) and presented syllogistic reasoning problems with incongruent information. Found that in imagination conditions, 2-…

Examined recall by 14- to 32-month-olds for multistep event sequences experienced at 13 to 20 months. Found that within step-length groups, there were no age differences in the length of time over which memory was evidenced. With prompts by event-related props, age-related differences in memory appeared. Age-related effects were particularly…

Two experiments examined differences in the early noun learning of English- and Japanese-speaking children. Found that English-speaking children's vocabularies were heavily lopsided with many more object than animal names, whereas Japanese-speaking children's vocabularies were more evenly balanced. Results suggested that early learners of English…

Infants follow the gaze direction of others from the middle of the first year of life. In attempting to determine how infants understand the looking behavior of adults, a number of recent studies have blocked the adult's line of sight in some way (e.g. with a blindfold or with a barrier). In contrast, in the current studies an adult looked behind…

Analyzed 104 language samples obtained from 42 different normal language learning children at 15, 19, and 35 months of age for the proportional use of 11 grammatical morphemes. Wide variability was found among the samples in the proportional use of each morpheme. (49 references) (JL)

Compared comprehension of novel communicative signs to assist 2.5- and 3-year-old humans, chimpanzees, and orangutans find hidden objects during a hiding-finding game. Found that children at both ages performed above chance with all signs. No ape performed above chance for any signs not known before the experiment despite three times as many…

Patterns of growth in one language in relation to growth in the other and also with respect to growth in both languages were studied in a group of 20 bilingual (English/Spanish) infants ages 10 to 30 months. The rate and pace of development were similar in both groups; differences among the bilinguals included their use of "referential"…

Compared parental perceptions of the use of internal information sources--intuitions, religious beliefs, personal childhood experiences--to use of external sources for information about their toddlers' development. Found that parents perceived the internal sources as being used more frequently and as more useful for information on their child's…

This study of parents of 121 toddlers with disabilities found that fathers reported more stress related to their child's temperament and the father-child relationship, while mothers reported more stress from the personal consequences of parenting. Fathers were more sensitive to effects of the family environment, whereas mothers were more affected…

Administered the MacArthur Communicative Development Inventory to 25 bilingual (English/Spanish) and 35 monolingual children who were furnishing data for longitudinal study. Assessment of the degree of overlap between bilingual children's lexical development in their two languages showed that they developed early vocabulary at the same rate as…