Factors affecting consonant production accuracy in children with cochlear implants: Expressive vocabulary and maternal education.

BACKGROUND: Despite the ability of cochlear implants (CIs) to provide children with access to speech, there is considerable variability in spoken language outcomes. Research aimed at identifying factors influencing speech production accuracy is needed. AIMS: To characterize the consonant production accuracy of children with cochlear implants (CWCI) and an age-matched group of children with typical hearing (CWTH) and to explore several factors that potentially affect the ability of both groups to accurately produce consonants. METHODS & PROCEDURES: We administered the Bankson-Bernthal Test of Phonology (BBTOP) to a group of 25 CWCI (mean age = 4;9, SD = 1;6, range = 3;2-8;5) implanted prior to 30 months of age with a mean duration of implant usage of 3;6 and an age-matched group of 25 CWTH (mean age = 5;0, SD = 1;6, range = 3;1-8;6). The recorded results were transcribed, and the accuracy of the target consonants was determined. Expressive vocabulary size estimates were obtained from a language sample using the number of different words (NDW). A parent questionnaire provided information about maternal education, duration of CIs experience and other demographic characteristics of each child. OUTCOMES & RESULTS: The CWCI group demonstrated some similarities to, and some differences from, their hearing peers. The CWCI demonstrated poorer consonant production accuracy overall and in various phonetic categories and word positions. However, both groups produced initial consonants more accurately than final consonants. Whilst CWCI had poorer production accuracy than CWTH for all phonetic categories (stops, nasals, fricatives, affricates, liquids and glides and consonant clusters), both groups exhibited similar error patterns across categories. For CWCI, the factors most related to consonant production accuracy when considered individually were expressive vocabulary size, followed by duration of CI experience, chronological age, maternal education and gender. The combination of maternal education and vocabulary size resulted in the best model of consonant production accuracy for this group. For the CWTH, chronological age followed by vocabulary size were most related to consonant production accuracy. No combination of factors yielded an improved model for the CWTH. CONCLUSIONS & IMPLICATIONS: Whilst group differences in production accuracy between the CWCI and CWTH were found, the pattern of errors was similar for the two groups of children, suggesting that the children are at earlier stages of overall consonant production development. Although duration of CI experience was a significant covariate in a single-variable model of consonant production accuracy for CWCI, the best multivariate model of consonant production accuracy for these children was based on the combination of expressive vocabulary size and maternal education. WHAT THIS PAPER ADDS: What is already known on the subject Research has shown that a range of factors is associated with consonant production accuracy by CWCIs, including factors such as the age at implant, duration of implant use, gender, other language skills and maternal education. Despite numerous studies that have examined speech sound production in these children, most have explored a limited number of factors that might explain the variability in scores obtained. Research that examines the potential role of a range of child-related and environmental factors in the same children is needed to determine the predictive role of these factors in speech production outcomes. What this paper adds to the existing knowledge Whilst the consonant production accuracy was lower for the CWCIs than for their typically hearing peers, there were some similarities suggesting that these children are experiencing similar, but delayed, acquisition of consonant production skills to that of their hearing peers. Whilst several factors are predictive of consonant production accuracy in children with implants, vocabulary diversity and maternal education, an indirect measure of socio-economic status, were the best combined predictors of consonant production accuracy. What are the potential or actual clinical implications of this work? Understanding the factors that shape individual differences in CWCI speech production is important for effective clinical decision-making and intervention planning. The present findings point to two potentially important factors related to speech sound production beyond the duration of robust hearing in CWCI, namely, a lexical diversity and maternal education. This suggests that intervention is likely most efficient that addresses both vocabulary development and speech sound development together. The current findings further suggest the importance of parental involvement and commitment to spoken language development and the importance of receiving early and consistent intervention aimed both at skill development and parental efficacy.

Babbling in extremely premature infants at 12 months corrected age.

Babbling is an important precursor to speech in infancy, and deviations from the typical babbling development can predict later difficulties in speech, language, and communication. This cross-sectional study aimed to investigate babbling and early speech in Swedish extremely premature infants. Samples of babbling were collected from 20 extremely premature infants (EPT group) at the corrected age of 12 months. Data collection was home-based and consisted of an audio-video recording of each infant playing with a parent. Presence of canonical babbling (CB), and three oral stop variables distinctive of typical babbling, and consonant inventory were assessed. The assessment was performed during a standardised observation of babbling. Data from the EPT group were compared to previously collected data of a reference group of 20 10-month-old infants without known medical diagnoses. The results showed that the EPT group had a lower proportion of infants producing CB, and that they used a significantly smaller consonant inventory compared to the reference group. Although not statistically significant, oral stops were less frequently found in the EPT group. The findings of a restricted consonant inventory and low proportion of CB in the EPT group are not surprising considering that the group has been found to be at risk of speech and language delay in toddlerhood. Still, further research is needed to explore whether babbling at 12 months can predict speech and language skills at an older age in extremely premature infants.

Positional asymmetries in consonant production and intelligibility in dysarthric speech.

Consonant production errors are common in dysarthric speech, but not all consonants are affected to the same extent. Currently, only limited knowledge exists regarding whether different positional allophones are affected to varying degrees in dysarthric speech. The aim of this study was to investigate the effect of consonants' position-in-words on consonant production accuracy and their relevance to speech intelligibility. To this end, the percentage of correctly articulated consonants was analyzed with respect to position-in-words, manner of articulation, and speakers' overall intelligibility in dysarthric speech secondary to cerebral palsy. Results revealed that consonants were generally more accurate in initial positions than other positions, and when they were singletons rather than clusters. However, fricatives, a category commonly noted for frequent misarticulations, exhibited no significant positional effects, indicating that fricatives were affected to a similar degree across all word positions. In addition, positional asymmetry manifested to a greater degree as intelligibility decreased. Finally, the strength of the relationship between consonant production accuracy and intelligibility varied depending on positions-in-words, with strong correlations in the medial and final cluster positions but no significant correlation for fricatives in the initial and final singleton positions. The correlation was markedly low for the initial consonants, possibly due to the resistance of initial consonants to production errors. The positional asymmetry found in this study necessitates more research on non-initial consonants and clusters for their potential in improving consonant production and speech intelligibility as a part of dysarthria management.

Impact of auditory variables on consonant production in babbling and early speech in children with moderate hearing loss - a longitudinal study.

This longitudinal study aimed to investigate early consonant production and the impact of hearing aid (HA) use, and aided audibility in Swedish children with moderate hearing loss (CHL) who received amplification before 6 months of age. CHL (n = 11) and children with normal hearing (CNH) (n = 11) were followed-up at 10, 18, and 36 months of age. At 10 months of age, the CHL used significantly fewer oral stops (p < 0.01), dental/alveolar stops (p < 0.05) and had a significantly fewer number of different true consonants (p < 0.01). At 18 months, there were no significant differences between the groups regarding presence of oral stops, and dental/alveolar stops, but the significant difference in the number of different true consonants remained (p < 0.00). At 36 months of age, consonant proficiency did not differ between the groups. A higher number of hours of HA use was associated with the presence of consonant variables at 10 months. Aided audibility showed weak to moderate correlations with number of consonants produced and proficiency. This group of children presented with initial delays in their early consonant production but seemed to catch up as they aged. Consistency of HA use from initial fitting is an important factor that may decrease the possible delays in the development of early consonant production and proficiency in CHL by 36 months of age.

Phonology in Swedish-speaking 3-year-olds born with cleft lip and palate and the relationship with consonant production at 18 months.

BACKGROUND: Approximately 50% of children born with cleft palate present speech difficulties around 3 years of age, and several studies report on persisting phonological problems after palatal closure. However, studies on early phonology related to cleft palate are few and have so far mainly been carried out on English-speaking children. Studies on phonology related to cleft palate in languages other than English are also warranted. AIMS: To assess phonology in Swedish-speaking children born with and without unilateral cleft lip and palate (UCLP) at 3 years of age, and to identify variables at 18 months that are associated with restricted phonology at age 3 years. METHODS & PROCEDURES: Eighteen consecutive children born with UCLP and 20 children without cleft lip and palate were included. Transcriptions of audio recordings at 18 months and 3 years were used. Per cent correct consonants adjusted for age (PCC-A), the number of established phonemes, and phonological simplification processes at 3 years were assessed and compared with different aspects of consonant inventory at 18 months. OUTCOMES & RESULTS: PCC-A, the number of established phonemes, and the total number of phonological processes differed significantly at 3 years between the two groups. Total number of oral consonants, oral stops, dental/alveolar oral stops and number of different oral stops at 18 months correlated significantly with PCC-A at 3 years in the UCLP group. CONCLUSIONS & IMPLICATIONS: As a group, children born with UCLP displayed deviant phonology at 3 years compared with peers without cleft lip and palate. Measures of oral consonant and stop production at 18 months might be possible predictors for phonology at 3 years in children born with cleft palate.

Consonant production and intelligibility in cri du chat syndrome.

This article focuses on consonant productions by a group of children with cri du chat syndrome (CdCS) and examines how various aspects of these productions contribute to these children's overall intelligibility. Eight children and adolescents with CdCS participated in the study, and the following four questions were addressed: (1) What are the characteristic features of the consonant inventories of the subjects in terms of size and types of consonants; (2) how do the subjects render the consonant phonemes of the target language; (3) to what degree do the subjects produce target-like words; and (4) what is the relationship between consonant production and intelligibility? For the majority of our subjects, we found low proportions of correctly produced consonants, small consonant inventories with several recurrent types of deviant consonants, inaccuracy in realization of target phonemes and variable similarity to target words, all of which may contribute to reduced intelligibility.

Babbling and consonant production in children with hearing impairment who use hearing aids or cochlear implants - a pilot study.

Objective: To investigate early auditory prerequisites in relation to the use of canonical babbling (CB) and early consonant production in a heterogeneous group of children with hearing impairment (HI) and in comparison to controls with normal hearing (NH).Methods: Five children with unilateral or bilateral HI who used hearing aids (HA) (0;9-1;7 years) and six children with cochlear implants (CI) (0;10-2;0 years) were compared to data from 22 children with NH (0;10-1;6 years). Hearing age, type of HI and daily use of hearing technology (hours) was investigated in relation to CB ratio and consonant production. Analysis of babbling from video recordings during verbal interaction between a parent and child was independently performed by two observers. Intra- and inter-agreement were calculated.Results: Children with HI used less CB compared to children with NH. Less CB utterances and occurrences of dental/alveolar stops were found in children with HA who had a hearing age of 5 months and who used their hearing technology 5 h per day. The children with CI reached an expected CB ratio and consonant production after 8.5 months with daily fulltime use of CI.Conclusions: Even a mild hearing loss in early childhood may affect and delay the onset of important linguistic milestones like canonical babbling and consonant production. It was indicated that children with CI or HA might receive different attention and intervention services. Longer hearing age and full-time use of hearing technology may influence positively on CB ratio and consonant production in children with HI.

Assessing consonant production in children with cochlear implants.

OBJECTIVE: The objective of this study was to investigate the development of consonant inventory and accuracy in pediatric cochlear implant (CI) recipients and compare their performance to typical hearing (TH) children. METHODS: One hundred and twenty nine children with CIs, implanted between 6-38 months of age, and 30 age-matched children with TH participated in this study. Spontaneous speech samples were collected at 3.5 and 4.5 years chronological age and the first 100 different words spoken by each participant were transcribed. Two consonant production measures were subsequently calculated to assess consonant acquisition and mastery. The percentage of Consonants Correct (CC) was used for measuring accuracy and Consonant Diversity (CD), an inventory measure, was used to identify the number of different consonants spoken by each participant. Repeated measures analyses of variance were conducted to examine the differences in consonant production scores based on presence of CI (participants with CI versus typical hearing (TH) participants), and chronological age at data collection (3.5 years versus 4.5 years). RESULTS: CI recipients displayed lower consonant production scores compared to TH children. Children with the most device experience (32-38 months at 3.5 years) performed on par with their TH peers. CONCLUSIONS: The two measures used in this study together appear capable of comprehensively describing the changes in consonant production skills of children. Results from this study indicate that while most CI participants display lower scores compared to TH children, many of the CI users are able to produce speech sounds on par with TH children.

Consonant accuracy after severe pediatric traumatic brain injury: a prospective cohort study.

PURPOSE: The authors sought to describe longitudinal changes in Percentage of Consonants Correct-Revised (PCC-R) after severe pediatric traumatic brain injury (TBI), to compare the odds of normal-range PCC-R in children injured at older and younger ages, and to correlate predictor variables and PCC-R outcomes. METHOD: In 56 children injured between age 1 month and 11 years, PCC-R was calculated over 12 monthly sessions beginning when the child produced ≥ 10 words. At each session, the authors compared odds of normal-range PCC-R in children injured at younger (≤ 60 months) and older (> 60 months) ages. Correlations were calculated between final PCC-R and age at injury, injury mechanism, gender, maternal education, residence, treatment, Glasgow Coma Score, and intact brain volume. RESULTS: PCC-Rs varied within and between children. Odds of normal-range PCC-R were significantly higher for the older than for the younger group at all sessions but the first; odds of normal-range PCC-R were 9 to 33 times higher in the older group in sessions 3 to 12. Age at injury was significantly correlated with final PCC-R. CONCLUSION: Over a 12-month period, severe TBI had more adverse effects for children whose ages placed them in the most intensive phase of PCC-R development than for children injured later.