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,…

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…

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…

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…

The acoustic realization of phrasal prominence is proposed to correlate with the order of V(erbs) and O(bjects) in natural languages. The present production study with 15 talkers of Japanese (OV) and English (VO) investigates whether the speech signal contains coverbal visual information that covaries with auditory prosody, in Infant- and…

Despite the fact that many of the world's languages use lexical tone, the majority of language acquisition studies has focused on non-tone languages. Research on tone languages has typically investigated wellknown tone languages such as Mandarin and Cantonese Chinese. The current study looked at a Limburgian dialect of Dutch that uses lexical…

Onomatopoeia are frequently identified amongst infants' earliest words (Menn & Vihman, 2011), yet few authors have considered why this might be, and even fewer have explored this phenomenon empirically. Here we analyze mothers' production of onomatopoeia in infant-directed speech (IDS) to provide an input-based perspective on these forms.…

Purpose: One promising early marker for autism and other communicative and language disorders is early infant speech production. Here we used daylong recordings of high- and low-risk infant-mother dyads to examine whether acoustic-prosodic alignment as well as two automated measures of infant vocalization are related to developmental risk status…

This study investigates prosodic modulation in the spontaneous canonical babble of congenitally deaf infants with cochlear implants (CI) and normally hearing (NH) infants. Research has shown that the acoustic cues to prominence are less modulated in CI babble. However acoustic measurements of individual cues to prominence give incomplete…

Previous studies have shown that infant-directed speech (IDS) differs from adult-directed speech (ADS) on a variety of dimensions. The aim of the current study was to investigate whether acoustic differences between IDS and ADS in English are modulated by prosodic structure. We compared vowels across the two registers (IDS, ADS) in both stressed…

One of the first challenges facing the young language learner is the task of segmenting words from a natural language speech stream, without prior knowledge of how these words sound. Studies with younger children find that children find it easier to segment words from fluent speech when the words are presented in infant-directed speech, i.e., the…

Infants perceive intonation contrasts early in development in contrast to lexical stress but similarly to lexical pitch accent. Previous studies have mostly focused on pitch height/direction contrasts; however, languages use a variety of pitch features to signal meaning, including differences in pitch timing. In this study, we investigate infants'…