Volubility of the human infant: Effects of parental interaction (or lack of it).

Although parental volubility, or amount of talk, has received considerable recent attention, infant volubility has received comparatively little attention despite its potential significance for communicative risk status and later linguistic and cognitive outcomes. Volubility of 16 typically developing infants from 2 to 11 months of age was longitudinally investigated in the present study across three social circumstances: parent talking to infant, parent not talking to infant and parent talking to interviewer while the infant was in the room. Results indicated that volubility was least in the Interview circumstance. There were no significant differences in volubility between the parent Talk and No Talk circumstances. Volubility was found to reduce with age. These results suggest that infants vocalise in a variety of circumstances, even when no one talks to or interacts with them. The presence of a stranger or perhaps overhearing adults speaking to each other, however, may significantly reduce infant volubility.

Mixed-Language Input and Infant Volubility: Friend or Foe?

Language mixing is a common feature of many bilingually-raised children's input. Yet how it is related to their language development remains an open question. The current study investigated mixed-language input indexed by observed (30-second segment) counts and proportions in day-long recordings as well as parent-reported scores, in relation to infant vocal activeness (i.e., volubility) when infants were 10 and 18 months old. Results suggested infants who received a higher score or proportion of mixed input in one-on-one social contexts were less voluble. However, within contexts involving language mixing, infants who heard more words were also the ones who produced more vocalizations. These divergent associations between mixed input and infant vocal development point for a need to better understand the causal factors that drive these associations.

Effectiveness of Aural-Oral Approach Based on Volubility of a Deaf Child with Late-Mapping Bilateral Cochlear Implants.

BACKGROUND: The purpose of this study was to investigate the effectiveness of aural-oral habilitation (AO) over the traditional speech-language therapy, based on the number of vocalization-volubility of a deaf child with late-mapping bilateral cochlear implants using sequential measurements. METHODS: The spontaneous productions during child interactions were analyzed. The child (CY, 7;0 years old) with a mean unaided pure-tone average (PTA) hearing loss >80 dB HL was assessed by using an assessment battery. Study design consisted of two phases: (a) baseline (end of speech therapy) and (b) end of AO treatment. Protophones were analyzed via acoustical analysis using PRAAT software. RESULTS: One-way repeated-measure ANOVAs were conducted within and between phases. The analyses revealed significant differences between the 'phase' and the vocalization outcome (F = 9.4, df = 1, p = 0.035). Post hoc analyses revealed the significant difference between the mean number of disyllable vocalizations of AO approach (p = 0.05). The mean number of vocalizations was calculated for each protophone type, but no other significant difference was measured. CONCLUSIONS: AO approach proved effective as measured through volubility. The outcome of this study is indicative and is a starting point for broader research.

Early Vocal Development in Tuberous Sclerosis Complex.

BACKGROUND: Our goal was to assess for the first time early vocalizations as precursors to speech in audio-video recordings of infants with tuberous sclerosis complex (TSC). METHODS: We randomly selected 40 infants with TSC from the TSC Autism Center of Excellence Research Network dataset. Using human observers, we analyzed 74 audio-video recordings within a flexible software-based coding environment. During the recordings, infants were engaged in developmental testing. We determined syllables per minute (volubility), the number of consonant-vowel combinations, such as 'ba' (canonical babbling), and the canonical babbling ratio (canonical syllables/total syllables) and compared the data with two groups of typically developing (TD) infants. One comparison group's data had come from a laboratory setting, while the other's had come from all-day Language Environment Analysis recordings at home. RESULTS: Compared with TD infants in laboratory and all-day Language Environment Analysis recordings, entry into the canonical babbling stage was delayed in the majority of infants with TSC, and the canonical babbling ratio was low (TD mean = 0.346, SE = 0.19; TSC mean = 0.117, SE = 0.023). Volubility level in infants with TSC was less than half that of TD infants (TD mean = 9.82, SE = 5.78; TSC mean = 3.99, SE = 2.16). CONCLUSIONS: Entry into the canonical stage and other precursors of speech development were delayed in infants with TSC and may signal poor language and developmental outcomes. Future studies are planned to assess prediction of language and developmental outcomes using these measures in a larger sample and in more precisely comparable recording circumstances.

Vocalization frequency as a prognostic marker of language development following early cochlear implantation.

Despite their potential significance for later linguistic outcomes, early aspects of vocalization had been seriously undervalued in the past, and thus, minimally investigated until relatively recently. The present article sets out to critically examine existing evidence to: i) ascertain whether vocalization frequency (volubility) posits a plausible marker of cochlear implantation success in infancy, and ii) determine the clinical usefulness of post-implementation vocalization frequency data in predicting later language development. Only recent peer-reviewed articles with substantial impact on vocalization growth during the first year of life, examining sound production characteristics of normally hearing (NH) and hearing impaired infants fitted with cochlear implantation (CI) were mentioned. Recorded differences in linguistic performance among NH and CI infants are typically attributed to auditory deprivation. Infants who have undergone late CI, produce fewer syllables (low volubility) and exhibit late-onset babbling, especially those who received their CIs at the age of 12 months or thereafter. Contrarily, early recipients (before the 12-month of age) exhibit higher volubility (more vocalizations), triggered from CI-initiated auditory feedback. In other words, early CI provides infants with early auditory access to speech sounds, leading to advanced forms of babbling and increased post-implementation vocalization frequency. Current findings suggest vocalization frequency as a plausible criterion of the success of early CI. It is argued that vocalization frequency predicts language development and affects habilitation therapy.

Auditory brainstem implantation in children with hearing loss: Effect on speech production.

Auditory brainstem implantation (ABI) is a recent technique in children's hearing restoration. Up till now the focus in the literature has mainly been the perceptual outcomes after implantation, whereas the effect of ABI on spoken language is still an almost unexplored area of research. This study presents a one-year follow-up of the volubility of two children with ABI. The volubility of signed and oral productions is investigated and oral productions are examined in more detail. Results show clear developmental trends in both children, indicating a beneficial effect of ABI on spoken language development.

Acoustic properties of early vocalizations in infants with fragile X syndrome.

Fragile X syndrome (FXS) is a neurogenetic syndrome characterized by cognitive impairments and high rates of autism spectrum disorder (ASD). FXS is often highlighted as a model for exploring pathways of symptom expression in ASD due to the high prevalence of ASD symptoms in this population and the known single-gene cause of FXS. Early vocalization features-including volubility, complexity, duration, and pitch-have shown promise in detecting ASD in idiopathic ASD populations but have yet to be extensively studied in a population with a known genetic cause for ASD such as FXS. Investigating early trajectories of these features in FXS may inform our limited knowledge of potential mechanisms that predict later social communication outcomes. The present study addresses this need by presenting preliminary findings which (a) characterize early vocalization features in FXS relative to low-risk controls (LRC) and (b) test the specificity of associations between these features and language and ASD outcomes. We coded vocalization features during a standardized child-examiner interaction for 39 nine-month-olds (22 FXS, 17 LRC) whose clinical outcomes were assessed at 24 months. Our results provide preliminary evidence that within FXS, associations between vocalization features and 24-month language outcomes may diverge from those observed in LRC, and that vocalization features may be associated with later ASD symptoms. These findings provide a starting point for more research exploring these features as potential early markers of ASD in FXS, which in turn may lead to improved early identification methods, treatment approaches, and overall well-being of individuals with ASD. Autism Res2019. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Although vocal features of 9-month-olds with FXS did not differ from those of low-risk controls, several features were associated with later language and ASD outcomes at 24 months in FXS. These preliminary results suggest acoustic data may be related to clinical outcomes in FXS and potentially other high-risk populations. Further characterizing these associations may facilitate understanding of biological mechanisms and risk factors associated with social communication development and ASD.

Multiple Coordination Patterns in Infant and Adult Vocalizations.

The study of vocal coordination between infants and adults has led to important insights into the development of social, cognitive, emotional and linguistic abilities. We used an automatic system to identify vocalizations produced by infants and adults over the course of the day for fifteen infants studied longitudinally during the first two years of life. We measured three different types of vocal coordination: coincidence-based, rate-based, and cluster-based. Coincidence-based and rate-based coordination are established measures in the developmental literature. Cluster-based coordination is new and measures the strength of matching in the degree to which vocalization events occur in hierarchically nested clusters. We investigated whether various coordination patterns differ as a function of vocalization type, whether different coordination patterns provide unique information about the dynamics of vocal interaction, and how the various coordination patterns each relate to infant age. All vocal coordination patterns displayed greater coordination for infant speech-related vocalizations, adults adapted the hierarchical clustering of their vocalizations to match that of infants, and each of the three coordination patterns had unique associations with infant age. Altogether, our results indicate that vocal coordination between infants and adults is multifaceted, suggesting a complex relationship between vocal coordination and the development of vocal communication.