Previous studies have found correlations between parent input and child language outcomes, providing prima facie evidence for a causal relation. However, this could also reflect the effects of shared genes. The present study removed this genetic confound by measuring English vocabulary growth in 29 preschool-aged children (21 girls) aged…

Learning about emotions is an important part of children's social and communicative development. How does children's emotion-related vocabulary emerge over development? How may emotion-related information in caregiver input support learning of emotion labels and other emotion-related words? This investigation examined language production and input…

This article examined longitudinal relations among socioeconomic risk, maternal language input, child vocabulary, and child executive function (EF) in a large sample (N = 1,009) recruited for a prospective longitudinal study. Two measures of maternal language input derived from a parent-child picture book task, vocabulary diversity (VOCD), and…

Sperry, Sperry, and Miller (2018) aim to debunk what is called the 30-million-word gap by claiming that children from lower income households hear more speech than Hart and Risley ([Hart, B., 1995]) reported. We address why the 30-million-word gap should not be abandoned, and the importance of retaining focus on the vital ingredient to language…

Everyday activities are replete with contextual cues for infants to exploit in the service of learning words. Nelson's (1985) script theory guided the hypothesis that infants participate in a set of predictable activities over the course of a day that provide them with opportunities to hear unique language functions and forms. Mothers and their…

To evaluate which features of spoken language aid infant word learning, a corpus of infant-directed speech (M. R. Brent & J. M. Siskind, 2001) was characterized on several linguistic dimensions and statistically related to the infants' vocabulary outcomes word by word. Comprehension (at 12 and 15 months) and production (15 months) were…

The unique relation of language use (i.e., output) to language growth was investigated for forty-seven 30-month-old Spanish-English bilingual children (27 girls, 20 boys) whose choices of which language to speak resulted in their levels of English output differing from their levels of English input. English expressive vocabularies and receptive…

This study employs the Specificity Principle to examine the relative impacts of external (input quantity at home and at school, number of books and reading frequency at home, teachers' degree and experience, language usage, socioeconomic status) and internal factors (children's working memory, nonverbal intelligence, learning-related…

Quantity and quality of caregiver input was examined longitudinally in a sample of 50 parent-child dyads to determine which aspects of input contribute most to children's vocabulary skill across early development. Measures of input gleaned from parent-child interactions at child ages 18, 30, and 42 months were examined in relation to children's…

Vowels with extreme articulatory-acoustic properties act as natural referents. Infant perceptual asymmetries point to an underlying bias favoring these referent vowels. However, as language experience is gathered, distributional frequency of speech sounds could modify this initial bias. The perception of the /i/-/e/ contrast was explored in 144…

This study investigated the relation between teachers' (N = 22) use of sophisticated and complex language in urban middle-school classrooms and their students' (mean age at pretest = 11.51 years; N = 782; 568 language minority and 247 English only) vocabulary knowledge. Using videotaped classroom observations, teachers' speech was transcribed and…