Naturalistic studies show that children can create language-like communication systems in the absence of conventional language. However, experimental evidence is mixed. We address this discrepancy using an experimental paradigm that simulates naturalistic sign creation. Specifically, we tested if a sample of 6- to 12-year-old children (52 girls…

We explored the ability of children to adapt their communication to the needs of their communication partner. Monolingual and bilingual 3-year-old children (N = 110) observed two puppets looking for puzzle pieces. One puppet showed its appreciation of the children's help, the other puppet wanted to solve the puzzle on its own. The children's…

People sometimes commit 'egocentric errors', failing to ignore their own perspective when interpreting others' communication. Training imitation-inhibition, when participants perform the opposite action from another person, facilitates subsequent perspective-taking in adults. This study tested whether imitation-inhibition training also facilitates…

This study examined how top-down control influenced letter-speech sound (L-SS) learning, the initial phase of learning to read. In 2020, 107 Dutch children (53 boys, M[subscript age] = 106.845 months) learned eight L-SS correspondences, either preceded by goal-directed or implicit instructions. Symbol knowledge and artificial word-reading ability…

Maternal responses to infant facial expressions were examined in two socioeconomically diverse samples of South African mothers (Study I, N = 111; and Study II, N = 214; age: 17-44 years) using pupil and gaze tracking. Study I showed increased pupil response to infant distress expressions in groups recruited from private as compared to public…

This study investigated transfer effects of gaze-interactive attention training to more complex social and cognitive skills in infancy. Seventy 9-month-olds were assigned to a training group (n = 35) or an active control group (n = 35). Before, after, and at 6-week follow-up both groups completed an assessment battery assessing transfer to…

Studies of infant motor development in autism spectrum disorder (ASD) have increased in recent years. This article synthesized this literature through meta-analysis to assess (a) whether infant motor ability differs in ASD relative to neurotypical controls; and (b) whether motor ability and communication are related in infants with ASD. Study 1…

Two independent cohorts (N = 155, N = 126) of infants at high and low risk for autism spectrum disorder (ASD) were followed prospectively between 6 and 36 months of age, when n = 46 were diagnosed with ASD. Gaze to adult faces was coded--during a developmental assessment (Cohort 1) or a play interaction (Cohort 2). Across both cohorts, most…

Studies have suggested that language and executive function (EF) are strongly associated. Indeed, the two are difficult to separate, and it is particularly difficult to determine whether one skill is more dependent on the other. Deafness provides a unique opportunity to disentangle these skills because in this case, language difficulties have a…

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…

Amid growing controversy about the oft-cited "30-million-word gap," this investigation uses language data from five American communities across the socioeconomic spectrum to test, for the first time, Hart and Risley's (1995) claim that poor children hear 30 million fewer words than their middle-class counterparts during the early years…

This study investigated how great apes and human infants use imperative pointing to request objects. In a series of three experiments (infants, N = 44; apes, N = 12), subjects were given the opportunity to either point to a desired object from a distance or else to approach closer and request it proximally. The apes always approached close to the…

Findings are presented from the first randomized control trial of the effects of encouraging symbolic gesture (or "baby sign") on infant language, following 40 infants from age 8 months to 20 months. Half of the mothers were trained to model a target set of gestures to their infants. Frequent measures were taken of infant language…

Retrospective studies indicate 2 major classes of autism spectrum disorder (ASD) onset: early and later, after a period of relatively healthy development. This prospective, longitudinal study examined social, language, and motor trajectories in 235 children with and without a sibling with autism, ages 6-36 months. Children were grouped as: ASD…

Human neonates prefer listening to speech compared to many nonspeech sounds, suggesting that humans are born with a bias for speech. However, neonates' preference may derive from properties of speech that are not unique but instead are shared with the vocalizations of other species. To test this, thirty neonates and sixteen 3-month-olds were…