Search

The use of spoken and written language is a fundamental human capacity. Individual differences in reading- and language-related skills are influenced by genetic variation, with twin-based heritability estimates of 30 to 80% depending on the trait. The genetic architecture is complex, heterogeneous, and multifactorial, but investigations of contributions of single-nucleotide polymorphisms (SNPs) were thus far underpowered. We present a multicohort genome-wide association study (GWAS) of five traits assessed individually using psychometric measures (word reading, nonword reading, spelling, phoneme awareness, and nonword repetition) in samples of 13,633 to 33,959 participants aged 5 to 26 y. We identified genome-wide significant association with word reading (rs11208009, P = 1.098 × 10 -8 ) at a locus that has not been associated with intelligence or educational attainment. All five reading-/language-related traits showed robust SNP heritability, accounting for 13 to 26% of trait variability. Genomic structural equation modeling revealed a shared genetic factor explaining most of the variation in word/nonword reading, spelling, and phoneme awareness, which only partially overlapped with genetic variation contributing to nonword repetition, intelligence, and educational attainment. A multivariate GWAS of word/nonword reading, spelling, and phoneme awareness maximized power for follow-up investigation. Genetic correlation analysis with neuroimaging traits identified an association with the surface area of the banks of the left superior temporal sulcus, a brain region linked to the processing of spoken and written language. Heritability was enriched for genomic elements regulating gene expression in the fetal brain and in chromosomal regions that are depleted of Neanderthal variants. Together, these results provide avenues for deciphering the biological underpinnings of uniquely human traits.

IMPORTANCE Hearing loss (HL) in children can be deleterious to their speech and language development. The standard of practice has been early provision of hearing aids (HAs) to moderate these effects; however, there have been few empirical studies evaluating the effectiveness of this practice on speech and language development among children with mild-to-severe HL. OBJECTIVE To investigate the contributions of aided hearing and duration of HA use to speech and language outcomes in children with mild-to-severe HL. DESIGN, SETTING, AND PARTICIPANTS An observational cross-sectional design was used to examine the association of aided hearing levels and length of HA use with levels of speech and language outcomes. One hundred eighty 3- and 5-year-old children with HL were recruited through records of Universal Newborn Hearing Screening and referrals from clinical service providers in the general community in 6 US states. INTERVENTIONS All but 4 children had been fitted with HAs, and measures of aided hearing and the duration of HA use were obtained. MAIN OUTCOMES AND MEASURES Standardized measures of speech and language ability were obtained. RESULTS Measures of the gain in hearing ability for speech provided by the HA were significantly correlated with levels of speech (ρ179 = 0.20; P = .008) and language: ρ155 = 0.21; P = .01) ability. These correlations were indicative of modest levels of association between aided hearing and speech and language outcomes. These benefits were found for children with mild and moderate-to-severe HL. In addition, the amount of benefit from aided hearing interacted with the duration of HA experience (Speech: F4,161 = 4.98; P < .001; Language: F4,138 = 2.91; P < .02). Longer duration of HA experience was most beneficial for children who had the best aided hearing. CONCLUSIONS AND RELEVANCE The degree of improved hearing provided by HAs was associated with better speech and language development in children. In addition, the duration of HA experience interacted with the aided hearing to influence outcomes. These results provide support for the provision of well-fitted HAs to children with HL. In particular, the findings support early HA fitting and HA provision to children with mild HL.

Objectives: Few studies have examined the long-term effect of age at implantation on outcomes using multiple data points in children with cochlear implants. The goal of this study was to determine whether age at implantation has a significant, lasting impact on speech perception, language, and reading performance for children with prelingual hearing loss., Design: A linear mixed-model framework was used to determine the effect of age at implantation on speech perception, language, and reading abilities in 83 children with prelingual hearing loss who received cochlear implants by the age of 4 years. The children were divided into two groups based on their age at implantation: (1) under 2 years of age and (2) between 2 and 3.9 years of age. Differences in model-specified mean scores between groups were compared at annual intervals from 5 to 13 years of age for speech perception, and 7 to 11 years of age for language and reading., Results: After controlling for communication mode, device configuration, and preoperative pure-tone average, there was no significant effect of age at implantation for receptive language by 8 years of age, expressive language by 10 years of age, reading by 7 years of age. In terms of speech-perception outcomes, significance varied between 7 and 13 years of age, with no significant difference in speech-perception scores between groups at ages 7, 11, and 13 years. Children who used oral communication (OC) demonstrated significantly higher speech-perception scores than children who used total communication (TC). OC users tended to have higher expressive language scores than TC users, although this did not reach significance. There was no significant difference between OC and TC users for receptive language or reading scores., Conclusions: Speech perception, language, and reading performance continue to improve over time for children implanted before 4 years of age. The present results indicate that the effect of age at implantation diminishes with time, particularly for higher-order skills such as language and reading. Some children who receive cochlear implants after the age of 2 years have the capacity to approximate the language and reading skills of their earlier-implanted peers, suggesting that additional factors may moderate the influence of age at implantation on outcomes over time.

Language impairment (LI) and reading disability (RD) are common pediatric neurobehavioral disorders that frequently co-occur, suggesting they share etiological determinants. Recently, our group identified prenatal nicotine exposure as a factor for RD and poor reading performance. Using smoking questionnaire and language data from the Avon Longitudinal Study of Parents and Children, we first determined if this risk could be expanded to other communication disorders by evaluating whether prenatal nicotine exposure increases risk for LI and poor performance on language tasks. Prenatal nicotine exposure increased LI risk (OR = 1.60; p = 0.0305) in a dose-response fashion with low (OR = 1.25; p = 0.1202) and high (OR = 3.84; p = 0.0002) exposures. Next, hypothesizing that the effects of prenatal nicotine may also implicate genes that function in nicotine related pathways, we determined whether known nicotine dependence (ND) genes associate with performance on language tasks. We assessed the association of 33 variants previously implicated in ND with LI and language abilities, finding association between ANKK1/DRD2 and performance on language tasks (p≤0.0003). The associations of markers within ANKK1 were replicated in a separate LI case-control cohort (p<0.05). Our results show that smoking during pregnancy increases the risk for LI and poor performance on language tasks and that ANKK1/DRD2 contributes to language performance. More precisely, these findings suggest that prenatal environmental factors influence in utero development of neural circuits vital to language. Our association of ANKK1/DRD2 further implicates the role of nicotine-related pathways and dopamine signaling in language processing, particularly in comprehension and phonological memory.

This study investigated the development of tense markers (e.g., past tense -ed) in children with cochlear implants (CIs) over a 3-year span. Nine children who received CIs before 30 months of age participated in this study at three, four, and five years postimplantation. Nine typical 3-, 4-, and 5-year- olds served as control groups. All children participated in a story-retell task. Percent correct of tense marking in the task was computed. Within the groups, percent correct of tense marking changed significantly in children with CIs and in typical children who had more hearing experience. Across the groups, children with CIs were significantly less accurate in tense marking than typical children at four and five years postimplantation. In addition, the performance of tense marking in children with CIs was correlated with their speech perception skills at earlier time points. Errors of tense marking tended to be omission rather than commission errors in typical children as well as in children with CIs. The findings suggested that despite the perceptual and processing constraints, children who received CIs may learn tense marking albeit with a delayed pattern.

Purpose: Prior work (Guo, Owen, & Tomblin, 2010) has shown that at the group level, auxiliary is production by young English-speaking children was symmetrical across lexical noun and pronominal subjects. Individual data did not uniformly reflect these patterns. On the basis of the framework of the gradual morphosyntactic learning (GML) hypothesis, the authors tested whether the addition of a theoretically motivated developmental measure, tense productivity (TP), could assist in explaining these individual differences., Method: Using archival data from 20 children between age 2;8 and 3;4 (years;months), the authors tested the ability of 3 developmental measures (TP; finite verb morphology composite, FVMC; mean length of utterance, MLU) to predict use of auxiliary is with different subject types., Results: TP, but not MLU or FVMC, significantly improved model fit. Children with low TP scores produced auxiliary is more accurately with pronominal subjects than with lexical subjects. The facilitative effect of pronominal subjects on the production of auxiliary is, however, was not found in children with high TP scores., Conclusion: The finding that the effect of subject types on the production accuracy of auxiliary is changed with children's TP is consistent with the GML hypothesis.

Purpose: This study characterized the development of speech sound production in prelingually deaf children with a minimum of 8 years of cochlear implant (CI) experience., Method: Twenty-seven pediatric CI recipients' spontaneous speech samples from annual evaluation sessions were phonemically transcribed. Accuracy for these speech samples was evaluated in piecewise regression models., Results: As a group, pediatric CI recipients showed steady improvement in speech sound production following implantation, but the improvement rate declined after 6 years of device experience. Piecewise regression models indicated that the slope estimating the participants' improvement rate was statistically greater than 0 during the first 6 years postimplantation, but not after 6 years. The group of pediatric CI recipients' accuracy of speech sound production after 4 years of device experience reasonably predicts their speech sound production after 5-10 years of device experience., Conclusions: The development of speech sound production in prelingually deaf children stabilizes after 6 years of device experience, and typically approaches a plateau by 8 years of device use. Early growth in speech before 4 years of device experience did not predict later rates of growth or levels of achievement. However, good predictions could be made after 4 years of device use.

Purpose: This study investigated the acoustic characteristics of pediatric cochlear implant (CI) recipients' imitative production of rising speech intonation, in relation to the perceptual judgments by listeners with normal hearing (NH)., Method: Recordings of a yes-no interrogative utterance imitated by 24 prelingually deafened children with a CI were extracted from annual evaluation sessions. These utterances were perceptually judged by adult NH listeners in regard with intonation contour type (non-rise, partial-rise, or full-rise) and contour appropriateness (on a 5-point scale). Fundamental frequency, intensity, and duration properties of each utterance were also acoustically analyzed., Results: Adult NH listeners' judgments of intonation contour type and contour appropriateness for each CI participant's utterances were highly positively correlated. The pediatric CI recipients did not consistently use appropriate intonation contours when imitating a yes-no question. Acoustic properties of speech intonation produced by these individuals were discernible among utterances of different intonation contour types according to NH listeners' perceptual judgments., Conclusions: These findings delineated the perceptual and acoustic characteristics of speech intonation imitated by prelingually deafened children and young adults with a CI. Future studies should address whether the degraded signals these individuals perceive via a CI contribute to their difficulties with speech intonation production.

Objective: Mandarin is a lexical tone language in which four tones are crucial for determining lexical meanings. Acquisition of such a tone system may be challenging to prelingually deaf children with cochlear implants because, as recent studies have shown, cochlear implant devices are ineffective in encoding voice pitch information required for tone recognition. This study aimed to investigate Mandarin tone production and perception skills of children with cochlear implants., Design: Thirty prelingually deaf children with cochlear implants, ages 6;0 (yr;mo) to 12;6, participated. These children received their implants at an average age of 5;8, with a range from 2;3 to 10;3. The average length of their cochlear implant experience was 3;7, with a range from 1;7 to 6;5. Tasks of tone production and tone identification involved a pictorial protocol of 48 words containing the targeted tones in either monosyllabic or disyllabic forms., Results: The average scores for tone production was 53.09% (SD = 15.42), and for tone identification was 72.88% (SD = 19.68; chance level = 50%). Significant differences were found in the percentages across the production or identification of tone types or tone pairs. The children with exceptional performance in tone production tended to also perform well in tone identification. The children's performance levels in tone identification and production were also discussed in relation to the factors of age at implantation and length of cochlear implant experience., Conclusions: The present results suggest that the majority of prelingually deaf children with cochlear implants did not master Mandarin tone production. However, a small group of participants demonstrated nearly perfect skills of Mandarin tone production in addition to tone perception. Thus, it is necessary to consider factors other than the device's limitations to explain these high levels of performance in the perception and production of Mandarin lexical tones., (Copyright 2004 Lippincott Williams and Wilkins)

This study examined nonword repetition performance in a population-based sample of school-age children. A total of 581 second graders who were participating in a longitudinal, epidemiologic investigation of specific language impairment (SLI) were administered the Nonword Repetition Task (NRT) developed by Dollaghan & Campbell (1998). Performance was examined according to second-grade diagnostic category, presence/absence of language impairment, and treatment status. Results indicated that children with language impairment, as well as those in intervention, exhibited deficient nonword repetition skills compared to normal language controls. Findings also confirmed that the NRT is a culturally nonbiased measure of language processing. Results from likelihood ratio analyses indicated that NRT performance, though not sufficient on its own, may provide a useful index to assist in ruling in or ruling out language disorder.