Bayesian data analysis in the phonetic sciences: A tutorial introduction.

This tutorial analyzes voice onset time (VOT) data from Dongbei (Northeastern) Mandarin Chinese and North American English to demonstrate how Bayesian linear mixed models can be fit using the programming language Stan via the R package brms. Through this case study, we demonstrate some of the advantages of the Bayesian framework: researchers can (i) flexibly define the underlying process that they believe to have generated the data; (ii) obtain direct information regarding the uncertainty about the parameter that relates the data to the theoretical question being studied; and (iii) incorporate prior knowledge into the analysis. Getting started with Bayesian modeling can be challenging, especially when one is trying to model one's own (often unique) data.

Methods for eliciting, annotating, and analyzing databases for child speech development.

Methods from automatic speech recognition (ASR), such as segmentation and forced alignment, have facilitated the rapid annotation and analysis of very large adult speech databases and databases of caregiver-infant interaction, enabling advances in speech science that were unimaginable just a few decades ago. This paper centers on two main problems that must be addressed in order to have analogous resources for developing and exploiting databases of young children's speech. The first problem is to understand and appreciate the differences between adult and child speech that cause ASR models developed for adult speech to fail when applied to child speech.

Evaluation of the use of low-dose quetiapine and the risk of metabolic consequences: A retrospective review.

Introduction: Quetiapine fumarate is an atypical antipsychotic approved for the treatment of schizophrenia, major depressive disorder, and bipolar disorder. Due to the sedative effects observed at low doses, prescribers use quetiapine to aid patients with sleep disturbances. Current evidence has established that quetiapine can cause negative changes in metabolic parameters, but it is unknown if these consequences also occur at low doses.

Framing a socio-indexical basis for the emergence and cultural transmission of phonological systems.

Moulin-Frier et al. (2016) proffer a conceptual framework and computational modeling architecture for the investigation of the emergence of phonological universals for spoken languages. They validate the framework and architecture by testing to see whether universals such as the prevalence of triangular vowel systems that show adequate dispersion in the F1-F2-F3 space can fall out of simulations of referential communication between social agents, without building principles such as dispersion directly into the model.

Quantifying the Robustness of the English Sibilant Fricative Contrast in Children.

Purpose: Four measures of children's developing robustness of phonological contrast were compared to see how they correlated with age, vocabulary size, and adult listeners' correctness ratings.

Method: Word-initial sibilant fricative productions from eighty-one 2- to 5-year-old children and 20 adults were phonetically transcribed and acoustically analyzed. Four measures of robustness of contrast were calculated for each speaker on the basis of the centroid frequency measured from each fricative token.

Aligning the timelines of phonological acquisition and change.

This paper examines whether data from a large cross-linguistic corpus of adult and child productions can be used to support an assumed corollary of the Neogrammarian distinction between two types of phonological change. The first type is regular sound change, which is assumed to be incremental and so should show continuity between phonological development and the age-related variation observed in the speech community undergoing the change. The second type is dialect borrowing, which could show an abrupt discontinuity between developmental patterns before and after the socio-historical circumstances that instigate it.

Voice onset time is necessary but not always sufficient to describe acquisition of voiced stops: The cases of Greek and Japanese.

The age at which children master adult-like voiced stops can generally be predicted by voice onset time (VOT): stops with optional short lag are early, those with obligatory lead are late. However, Japanese voiced stops are late despite having a short lag variant, whereas Greek voiced stops are early despite having consistent voicing lead. This cross-sectional study examines the acoustics of word-initial stops produced by English-, Japanese-, and Greek-speaking children aged 2 to 5, to investigate how these seemingly exceptional mastery patterns relate to use of other phonetic correlates.

Acquisition of initial /s/-stop and stop-/s/sequences in Greek.

Previous work on children's acquisition of complex sequences points to a tendency for affricates to be acquired before clusters, but there is no clear evidence of a difference in order of acquisition between clusters with /s/ that violate the Sonority Sequencing Principle (SSP), such as /s/ followed by stop in onset position, and other clusters that obey the SSP. One problem with studies that have compared the acquisition of SSP-obeying and SSP-violating clusters is that the component sounds in the two types of sequences were different.This paper examines the acquisition of initial /s/-stop and stop-/s/ sequences by sixty Greek children aged 2 through 5 years.

Why are Korean tense stops acquired so early: The role of acoustic properties.

Transcription-based studies have shown that tense stops appear before aspirated or lax stops in most Korean-acquiring children's speech. This order of mastery is predicted by the short lag Voice Onset Time (VOT) values of Korean tense stops, as this is the earliest acquired phonation type across languages. However, the tense stop also has greater motor demands than the other two phonation types, given its pressed voice quality (negative H1-H2) and its relatively high f0 value at vowel onset, word-initially.

Adapting a receptive vocabulary test for preschool-aged Greek-speaking children.

Background: Receptive vocabulary is an important measure for language evaluations. Therefore, norm-referenced receptive vocabulary tests are widely used in several languages. However, a receptive vocabulary test has not yet been normed for Modern Greek.

Generalizing over Lexicons to Predict Consonant Mastery.

When they first begin to talk, children show characteristic consonant errors, which are often described in terms that recall Neogrammarian sound change. For example, a Japanese child's production of the word kimono might be transcribed with an initial postalveolar affricate, as in typical velar-softening sound changes. Broad-stroke reviews of errors list striking commonalities across children acquiring different languages, whereas quantitative studies reveal enormous variability across children, some of which seems related to differences in consonant frequencies across different lexicons.

Deconstructing phonetic transcription: covert contrast, perceptual bias, and an extraterrestrial view of Vox Humana.

This article honours Adele Miccio's life work by reflecting on the utility of phonetic transcription. The first section reviews the literature on cases where children whose speech appears to neutralize a contrast in the adult language are found on closer examination to produce a contrast (covert contrast). This study presents evidence from a new series of perception studies that covert contrast may be far more prevalent in children's speech than existing studies would suggest.

Contrast and covert contrast: The phonetic development of voiceless sibilant fricatives in English and Japanese toddlers.

This paper examines the acoustic characteristics of voiceless sibilant fricatives in English-and Japanese-speaking adults and the acquisition of contrasts involving these sounds in 2- and 3-year-old children. Both English and Japanese have a two-way contrast between an alveolar fricative (/s/), and a postalveolar fricative (/∫/ in English and /ɕ/ in Japanese). Acoustic analysis of the adult productions revealed cross-linguistic differences in what acoustic parameters were used to differentiate the two fricatives in the two languages and in how well the two fricatives were differentiated by the acoustic parameters that were investigated.

Methodological questions in studying consonant acquisition.

Consonant mastery is one of the most widely used metrics of typical phonological acquisition and of phonological disorder. Two fundamental methodological questions concerning research on consonant acquisition are (1) how to elicit a representative sample of productions and (2) how to analyse this sample once it has been collected. This paper address these two questions by reviewing relevant aspects of experience in evaluating word-initial consonant accuracy from transcriptions of isolated-word productions elicited from 2- and 3-year-olds learning four different first languages representing a telling range of consonant systems (English, Cantonese, Greek, Japanese).

Some cross-linguistic evidence for modulation of implicational universals by language-specific frequency effects in phonological development.

While broad-focus comparisons of consonant inventories across children acquiring different language can suggest that phonological development follows a universal sequence, finer-grained statistical comparisons can reveal systematic differences. This cross-linguistic study of word-initial lingual obstruents examined some effects of language-specific frequencies on consonant mastery. Repetitions of real words were elicited from 2- and 3-year-old children who were monolingual speakers of English, Cantonese, Greek, or Japanese.

Phonological Knowledge in Typical and Atypical Speech-Sound Development.

This article discusses 4 types of phonological knowledge: knowledge of the acoustic and perceptual characteristics of speech sounds (perceptual knowledge), knowledge of the articulatory characteristics of speech sounds (articulatory knowledge), higher level knowledge of the ways that words can be divided into sounds and related phonotactic constraints on how sounds can be combined into words (higher level phonological knowledge), and knowledge of the ways that variation in pronunciation can be used to convey social identity (social-indexical knowledge). The first section of the article discusses the nature of these types of knowledge in adults. The second describes how they develop in children with typical language development.

Relationships between nonword repetition accuracy and other measures of linguistic development in children with phonological disorders.

A growing body of research has documented effects of phonotactic probability on young children's nonword repetition. This study extends this research in 2 ways. First, it compares nonword repetitions by 40 young children with phonological disorders with those by 40 same-age peers with typical phonological development on a nonword repetition task in which the frequency of embedded diphone sequences was varied.

The interaction between vocabulary size and phonotactic probability effects on children's production accuracy and fluency in nonword repetition.

Adults' performance on a variety of tasks suggests that phonological processing of nonwords is grounded in generalizations about sublexical patterns over all known words. A small body of research suggests that children's phonological acquisition is similarly based on generalizations over the lexicon. To test this account, production accuracy and fluency were examined in nonword repetitions by 104 children and 22 adults.