Infant-directed speech (IDS) is characterized by a range of register-typical characteristics. Many of those can be objectively measured, such as acoustic-prosodic and structural-linguistic modifications. Perceived vocal affect, however, is a socio-emotional IDS characteristic and is subjectively assessed. Vocal affect goes beyond acoustic-prosodic…

Successful word recognition requires that listeners attend to differences that are phonemic in the language while also remaining flexible to the variation introduced by different voices and accents. Previous work has demonstrated that American-English-learning 19-month-olds are able to balance these demands: although one-off one-feature…

Although both fathers and mothers speak differently in infant-directed speech (IDS) compared to adult-directed speech (ADS), the acoustic characteristics of present-day paternal IDS are still insufficiently understood. To extend this understanding, 11 fathers and 17 mothers in The Netherlands were recorded interacting with their infant…

Hudson Kam (2018) examined whether learning of a particular aspect of language that adults are known to have difficulty with (grammatical gender) could be improved by manipulating the learning experience of adults so that it was more like that of infants. Specifically, based on likely differences between adult and child learners' experiences as…

Beginning with the classic work of Shepard, Hovland, & Jenkins (1961), Type II visual patterns (e.g., exemplars are large white squares OR small black triangles) have held a special place in investigations of human learning. Recent research on Type II "linguistic" patterns has shown that they are relatively frequent across languages…

We assessed 24-month-old infants' lexical processing efficiency for both novel and familiar words. Prior work documented that 19-month-olds successfully identify referents of familiar words (e.g., The dog is so little) as well as novel words whose meanings were informed only by the surrounding sentence (e.g., The vep is crying), but that the speed…

Adult learners know that language is for communicating and that there are patterns in the language that need to be learned. This affects the way they engage with language input; they search for form-meaning linkages, and this effortful engagement could interfere with their learning, especially for things like grammatical gender that often have at…

We tested 12- and 18-month-old English-learning infants on a preferential-looking task which contrasted grammatically correct sentences using the determiner "the" vs. three ungrammatical conditions in which "the" was substituted by another English function word, a nonsense word, or omitted. Our design involved strict controls…

For adults, "no" and "not" change the truth-value of sentences they compose with. To investigate children's emerging understanding of these words, an experimenter hid a ball in a bucket or a truck, then gave an affirmative or negative clue (Experiment 1: "It's not in the bucket"; Experiment 2: "Is it in the…

Research has indicated differences in prosodic expression for infants-at-risk-of-autism spectrum disorders (ASD), and it has been proposed that caregiver speech to these infants may also be moderated prosodically. In typical development, the pitch range of maternal infant-directed speech (IDS) narrows and utterance intensity decreases with infant…

In spontaneous conversations between adults, words are often pronounced with fewer segments or syllables than their citation forms. The question arises whether infant-directed speech also contains phonetic reduction. If so, infants would be presented with speech input that enables them to acquire reduced variants from an early age. This study…

Examination of infant vocalization patterns across interactive and noninteractive contexts may facilitate better understanding of early communication development. In the current study, with 24 infant-parent dyads, infant volubility increased significantly when parent interaction ceased (presenting a "still face," or SF) after a period of…