Rhythm perception helps young infants find structure in both speech and music. However, it remains unknown whether categorical perception of suprasegmental linguistic rhythm signaled by a co-variation of multiple acoustic cues can be modulated by prior between- (music) and within-domain (language) experience. Here we tested 6-month-old…

Background: Variability in the vocabulary outcomes of children with cochlear implants (CIs) is partially explained by child-directed speech (CDS) characteristics. Yet, relatively little is known about whether and how mothers adapt their lexical and prosodic characteristics to the child's hearing status (before and after implantation, and compared…

This study compared the acoustic properties of 26 (100% female, 100% monolingual) Danish caregivers' spontaneous speech addressed to their 11- to 24-month-old infants (infant-directed speech, IDS) and an adult experimenter (adult-directed speech, ADS). The data were collected between 2016 and 2018 in Aarhus, Denmark. Prosodic properties of Danish…

There is a long-standing debate in the literature about the benefits that acoustic components of Infant Directed Speech (IDS) might have for infants' language acquisition. One of the highly contested features is vowel space expansion, which refers to the enlargement of the acoustic space between the corner vowels /i, u, a/ in IDS compared to Adult…

Research on the acoustic characteristics of Infant Directed Speech (IDS) in North American English indicates that it is generally higher-pitched than Adult Directed Speech (ADS) and has unique prosodic characteristics, which is commonly found across many spoken languages. However, very little research has addressed another important aspect of…

Purpose: The aim of this study was to investigate infants' listening preference for emotional prosodies in spoken words and identify their acoustic correlates. Method: Forty-six 3- to-12-month-old infants (M[subscript age] = 7.6 months) completed a central fixation (or look-to-listen) paradigm in which four emotional prosodies (happy, sad, angry,…

Purpose: The purpose of the present study was to examine whether there is a listening preference for child-directed speech (CDS) over backward speech in moderate-preterm infants (MPIs). Method: Eighteen MPIs of gestational age of 32.0 weeks (range: 32-34.06 weeks), chronological age of 8.09 months, and maturation age of 6.48 months served as the…

The Headturn Preference Procedure (HPP) is widely used in infant research. Previous studies have shown that speech perception measures obtained with HPP are related to later language skills which may make them a potential instrument for an early detection of developmental language risks. The present study assessed the reliability and stability of…

Previous research on infant-directed speech (IDS) and its role in infants' language development has largely focused on mothers, with fathers being investigated scarcely. Here we examine the acoustics of IDS as compared to adult-directed speech (ADS) in Norwegian mothers and fathers to 8-month-old infants, and whether these relate to direct…

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…

The functions of acoustic-phonetic modifications in infant-directed speech (IDS) remain a question: do they specifically serve to facilitate language learning via enhanced phonemic contrasts (the hyperarticulation hypothesis) or primarily to improve communication via prosodic exaggeration (the prosodic hypothesis)? The study of lexical tones…

Computational models of child language development can help us understand the cognitive underpinnings of the language learning process, which occurs along several linguistic levels at once (e.g., prosodic and phonological). However, in light of the replication crisis, modelers face the challenge of selecting representative and consolidated infant…

Purpose: This scoping review considers the acoustic features of a clear speech register directed to nonnative listeners known as foreigner-directed speech (FDS). We identify vowel hyperarticulation and low speech rate as the most representative acoustic features of FDS; other features, including wide pitch range and high intensity, are still under…

Purpose: Differences across language environments of prelingually deaf children who receive cochlear implants (CIs) may affect language acquisition; yet, whether mothers show individual differences in how they modify infant-directed (ID) compared with adult-directed (AD) speech has seldom been studied. This study assessed individual differences in…

The objective of this study was to examine the links between prosodic features of paternal Infant-Directed Speech (IDS) and child characteristics. Pitch variability measures were extracted from the speech samples of 50 fathers during unstructured play with their two-year-old children. Evidence for a link between child receptive language ability…