Language and reading impairments are associated with increased prevalence of non-right-handedness.

Handedness has been studied for association with language-related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non-right-handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex-matched controls identified from 10 distinct cohorts (age range 6-19 years old; European ethnicity) using a priori set criteria. A meta-analysis (Ncases  = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06-1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions.

A preliminary epidemiologic study of social (pragmatic) communication disorder in the context of developmental language disorder.

BACKGROUND: There is extremely limited population-based research on social (pragmatic) communication disorder (SCD). Population-based samples have the potential to better characterize the SCD phenotype by mitigating confounds and biases that are typical of convenience and clinical samples. AIMS: The aims of this preliminary epidemiologic study were to advance our understanding of the SCD phenotype relative to developmental language disorder (DLD), obtain an estimate of prevalence, identify risk factors and lay the groundwork for future population level research of SCD. METHODS & PROCEDURES: We analysed existing data from the EpiSLI Database to examine social communication skills in 393 8th grade (13-14 years) children with and without a history of DLD. The primary measure used to evaluate SCD was the Children's Communication Checklist (CCC-2). Two case definitions of SCD reflecting DSM-5 criteria were examined. Both definitions involved significant pragmatic impairment, employing a commonly adopted clinical cut-point of 1.5 SD. In one case, pragmatic deficits could occur along with structural language deficits and, in the other case (established using principal component analysis), pragmatic and social skills were disproportionately lower than structural language abilities. OUTCOMES & RESULTS: When using the first case definition, SCD was much more common in children with a history of DLD than without DLD and history of language disorder at kindergarten was a significant risk factor for SCD in adolescence. However, it is important to note that SCD could be found in children with no prior deficits in other aspects of language. When the second definition was employed, SCD was equally distributed across children with and without a history of DLD. Male sex was a significant risk factor using this case definition of SCD. The estimated prevalence of SCD ranged from 7% (SE = 1.5%) to 11% (SE = 1.7%), acknowledging that prevalence depends on the cut-point selected to determine communication disorder. CONCLUSIONS & IMPLICATIONS: These findings contribute to our understanding of the association between SCD and DLD by recognizing varying profiles of pragmatic and social communication difficulties, which in turn may help refine our diagnostic categories. Preliminary prevalence estimates of SCD can serve as an initial guidepost for identification and planning for intervention services for this condition. WHAT THIS PAPER ADDS: What is already known on this subject There is considerable debate about the diagnostic category of SCD and its relation to other neurodevelopmental disorders. What this study adds to existing knowledge Using data from a US-based epidemiologic sample of DLD, this study offers new information about the association between SCD and DLD, provides preliminary estimates of SCD prevalence, and identifies risk factors for SCD. Clinical implications of this study Improved understanding of possible profiles of pragmatic and social communication deficits will help to clarify diagnostic categories and preliminary prevalence estimates may assist with ensuring availability of adequate intervention services.

Aided Hearing Moderates the Academic Outcomes of Children With Mild to Severe Hearing Loss.

OBJECTIVES: There are very limited data regarding the spoken language and academic outcomes of children with mild to severe hearing loss (HL) during the elementary school years, and the findings of these studies are inconsistent. None of these studies have examined the possible role of aided hearing in these outcomes. This study used a large cohort of children to examine these outcomes and in particular to examine whether aided hearing moderates the effect of HL with regard to these outcomes. DESIGN: The spoken language, reading, writing, and calculation abilities were measured after second and fourth grades in children with mild to severe HL (children who are hard of hearing; CHH, n = 183) and a group of children with normal hearing (CNH, n = 91) after the completion of second and fourth grades. Also, among the CHH who wore hearing aids, aided better-ear speech intelligibility index values at the age of school entry were obtained. RESULTS: Oral language abilities of the CHH with mild and moderate HL were similar to the CNH at each grade. Children with moderately-severe HL (better-ear pure tone threshold >59 but <76 dB HL) had significantly poorer oral language and reading skills than the CNH at each grade. The children with mild and moderate HL did not differ from the CNH in oral language or reading. No differences were found between the CHH regardless of severity and CNH with regard to spelling, passage writing, or calculation. The degree to which hearing aids provided audible speech information played a moderating role in the oral language outcomes of CHH and this moderation of language mediated the relationship between the unaided hearing ability of the CHH and their academic outcomes. CONCLUSIONS: As a group, children with mild and moderate HL have good outcomes with regard to language and academic performance. Children with moderately-severe losses were less skilled in language and reading than the CNH and CHH children with mild and moderate losses. Audibility provided by hearing aids was found to moderate the effects of HL with respect to these outcomes. These findings emphasize the importance of including the effects of clinical interventions such as aided hearing when examining outcomes of CHH.

Early Literacy Predictors and Second-Grade Outcomes in Children Who Are Hard of Hearing.

This study contrasted the early literacy outcomes of children who are hard of hearing (CHH) with children with normal hearing (CNH). At age 5, prereading skills of oral language, phonological processing, and print knowledge were examined in CHH (N = 180) and CNH (N = 80). The CHH had poorer oral language and phonological processing abilities than the CNH but comparable knowledge of print. At age 8, measures of word reading, and reading comprehension yielded no differences between CHH (N = 108) and CNH (N = 62) except for reading comprehension for the moderately severe CHH. Reading achievement in CHH was found to exceed predictions based on prereading performance. This resilience was associated with gains in oral language during the early school years.

Nonverbal Visual Sequential Learning in Children With Cochlear Implants: Preliminary Findings.

The authors tested the hypothesis that children with cochlear implants (CIs) experience domain-general deficits in sequential learning. Twenty children with CIs and 40 children with normal hearing (NH) participated. Participants completed a serial reaction time task that measured implicit sequential learning. During random sequence phases, the CI group had significantly slower reaction times than the NH group. However, there were no significant differences in the rates of sequential learning between groups. Age at implantation was not significantly associated with learning rate in the CI group. Children with CIs demonstrated nonverbal sequential learning that is comparable to children with NH. Contrary to previous research, early auditory deprivation may not be associated with deficits in domain-general sequential learning, but may affect sequential processing. Further investigation is needed to understand the mechanisms underlying the overall delayed reaction times of children with CIs.

Medical Referral Patterns and Etiologies for Children With Mild-to-Severe Hearing Loss.

OBJECTIVES: To (1) identify the etiologies and risk factors of the patient cohort and determine the degree to which they reflected the incidence for children with hearing loss and (2) quantify practice management patterns in three catchment areas of the United States with available centers of excellence in pediatric hearing loss. DESIGN: Medical information for 307 children with bilateral, mild-to-severe hearing loss was examined retrospectively. Children were participants in the Outcomes of Children with Hearing Loss (OCHL) study, a 5-year longitudinal study that recruited subjects at three different sites. Children aged 6 months to 7 years at time of OCHL enrollment were participants in this study. Children with cochlear implants, children with severe or profound hearing loss, and children with significant cognitive or motor delays were excluded from the OCHL study and, by extension, from this analysis. Medical information was gathered using medical records and participant intake forms, the latter reflecting a caregiver's report. A comparison group included 134 children with normal hearing. A Chi-square test on two-way tables was used to assess for differences in referral patterns by site for the children who are hard of hearing (CHH). Linear regression was performed on gestational age and birth weight as continuous variables. Risk factors were assessed using t tests. The alpha value was set at p < 0.05. RESULTS: Neonatal intensive care unit stay, mechanical ventilation, oxygen requirement, aminoglycoside exposure, and family history were correlated with hearing loss. For this study cohort, congenital cytomegalovirus, strep positivity, bacterial meningitis, extracorporeal membrane oxygenation, and loop diuretic exposure were not associated with hearing loss. Less than 50% of children underwent imaging, although 34.2% of those scanned had abnormalities identified. No single imaging modality was preferred. Differences in referral rates were apparent for neurology, radiology, genetics, and ophthalmology. CONCLUSIONS: The OCHL cohort reflects known etiologies of CHH. Despite available guidelines, centers of excellence, and high-yield rates for imaging, the medical workup for children with hearing loss remains inconsistently implemented and widely variable. There remains limited awareness as to what constitutes appropriate medical assessment for CHH.

An Introduction to the Outcomes of Children with Hearing Loss Study.

The landscape of service provision for young children with hearing loss has shifted in recent years as a result of newborn hearing screening and the early provision of interventions, including hearing technologies. It is expected that early service provision will minimize or prevent linguistic delays that typically accompany untreated permanent childhood hearing loss. The post-newborn hearing screening era has seen a resurgence of interest in empirically examining the outcomes of children with hearing loss to determine if service innovations have resulted in expected improvements in children's functioning. The Outcomes of Children with Hearing Loss (OCHL) project was among these recent research efforts, and this introductory article provides background in the form of literature review and theoretical discussion to support the goals of the study. The Outcomes of Children with Hearing Loss project was designed to examine the language and auditory outcomes of infants and preschool-age children with permanent, bilateral, mild-to-severe hearing loss, and to identify factors that moderate the relationship between hearing loss and longitudinal outcomes. The authors propose that children who are hard of hearing experience limitations in access to linguistic input, which lead to a decrease in uptake of language exposure and an overall reduction in linguistic experience. The authors explore this hypothesis in relation to three primary factors that are proposed to influence children's access to linguistic input: aided audibility, duration and consistency of hearing aid use, and characteristics of caregiver input.

Epilogue: Conclusions and Implications for Research and Practice.

The primary purpose of the epilogue article is to synthesize the key findings from the Outcomes of Children with Hearing Loss (OCHL) study by presenting a set of 10 major conclusions. The conclusion statements provide a concise summary of the main results related to children's auditory and language outcomes and factors identified as moderators of these outcomes. The second section of this article summarizes the primary clinical implications that follow from the OCHL study in relation to three questions: (1) Can we afford to be complacent about the current outcomes of children who are hard of hearing? (2) Which malleable factors can be addressed to promote success through implementation of best practices? and (3) Which nonmalleable factors are consequential and what are their implications for practice? The authors end with some future research directions for the OCHL project.

Afterword: Lessons Learned About Multicenter Research Collaboration.

In this brief afterword, we discuss the challenges and lessons learned in the process of implementing a multisite, longitudinal study. Some of the lessons learned by the research team are shared regarding research design and analysis, strategies implemented to reduce threats to validity, and techniques used to promote teamwork and collaboration across sites.

Outcomes of Children with Hearing Loss: Data Collection and Methods.

OBJECTIVES: The primary objective of this article was to describe recruitment, data collection, and methods for a longitudinal, multicenter study involving children with bilateral mild to severe hearing loss. The goals of this research program were to characterize the developmental outcomes of children with mild to severe bilateral hearing loss during infancy and the preschool years. Furthermore, the researchers examined how these outcomes were associated with the child's hearing loss and how home background and clinical interventions mediated and moderated these outcomes. DESIGN: The participants in this study were children who are hard of hearing (CHH) and children with normal hearing (CNH) who provided comparison data. CHH were eligible for participation if (1) their chronological age was between 6 months and 7 years of age at the time of recruitment, (2) they had a better-ear pure-tone average of 25 to 75 dB HL, (3) they had not received a cochlear implant, (4) they were from homes where English was the primary language, and (5) they did not demonstrate significant cognitive or motor delays. Across the time span of recruitment, 430 parents of potential children with hearing loss made contact with the research group. This resulted in 317 CHH who qualified for enrollment. In addition, 117 CNH qualified for enrollment. An accelerated longitudinal design was used, in which multiple age cohorts were followed long enough to provide overlap. Specifically, children were recruited and enrolled continuously across an age span of 6.5 years and were followed for at least 3 years. This design allowed for tests of time (period) versus cohort age effects that could arise by changes in services and technology over time, yet still allowed for examination of important developmental relationships. RESULTS: The distribution of degree of hearing loss for the CHH showed that the majority of CHH had moderate or moderate-to-severe hearing losses, indicating that the sample undersampled children with mild HL. For mothers of both CHH and CNH, the distribution of maternal education level showed that few mothers lacked at least a high school education and a slight majority had completed a bachelor's degree, suggesting that this sample of research volunteers was more advantaged than the United States population. The test battery consisted of a variety of measures concerning participants' hearing and behavioral development. These data were gathered in sessions during which the child was examined by an audiologist and a speech-language examiner. In addition, questionnaires concerning the child's behavior and development were completed by the parents. CONCLUSION: The Outcomes of Children with Hearing Loss study was intended to examine the relationship between variation in hearing ability across children with normal and mild to severe hearing loss and variation in their outcomes across several domains of development. In addition, the research team sought to document important mediators and moderators that act between the hearing loss and the outcomes. Because the study design provided for the examination of outcomes throughout infancy and early childhood, it was necessary to employ a number of different measures of the same construct to accommodate changes in developmental performance across age. This resulted in a large matrix of measures across variable types and developmental levels, as described in this manuscript.

Language Outcomes in Young Children with Mild to Severe Hearing Loss.

OBJECTIVES: This study examined the language outcomes of children with mild to severe hearing loss during the preschool years. The longitudinal design was leveraged to test whether language growth trajectories were associated with degree of hearing loss and whether aided hearing influenced language growth in a systematic manner. The study also explored the influence of the timing of hearing aid fitting and extent of use on children's language growth. Finally, the study tested the hypothesis that morphosyntax may be at particular risk due to the demands it places on the processing of fine details in the linguistic input. DESIGN: The full cohort of children in this study comprised 290 children who were hard of hearing (CHH) and 112 children with normal hearing who participated in the Outcomes of Children with Hearing Loss (OCHL) study between the ages of 2 and 6 years. CHH had a mean better-ear pure-tone average of 47.66 dB HL (SD = 13.35). All children received a comprehensive battery of language measures at annual intervals, including standardized tests, parent-report measures, and spontaneous and elicited language samples. Principal components analysis supported the use of a single composite language score for each of the age levels (2, 3, 4, 5, and 6 years). Measures of unaided (better-ear pure-tone average, speech intelligibility index) and aided (residualized speech intelligibility index) hearing were collected, along with parent-report measures of daily hearing aid use time. Mixed modeling procedures were applied to examine the rate of change (227 CHH; 94 children with normal hearing) in language ability over time in relation to (1) degree of hearing loss, (2) aided hearing, (3) age of hearing aid fit and duration of use, and (4) daily hearing aid use. Principal components analysis was also employed to examine factor loadings from spontaneous language samples and to test their correspondence with standardized measures. Multiple regression analysis was used to test for differential effects of hearing loss on morphosyntax and lexical development. RESULTS: Children with mild to severe hearing loss, on average, showed depressed language levels compared with peers with normal hearing who were matched on age and socioeconomic status. The degree to which CHH fell behind increased with greater severity of hearing loss. The amount of improved audibility with hearing aids was associated with differential rates of language growth; better audibility was associated with faster rates of language growth in the preschool years. Children fit early with hearing aids had better early language achievement than children fit later. However, children who were fit after 18 months of age improved in their language abilities as a function of the duration of hearing aid use. These results suggest that the language learning system remains open to experience provided by improved access to linguistic input. Performance in the domain of morphosyntax was found to be more delayed in CHH than their semantic abilities. CONCLUSION: The data obtained in this study largely support the predictions, suggesting that mild to severe hearing loss places children at risk for delays in language development. Risks are moderated by the provision of early and consistent access to well-fit hearing aids that provide optimized audibility.

Characterization of the DYX2 locus on chromosome 6p22 with reading disability, language impairment, and IQ.

Reading disability (RD) and language impairment (LI) are common neurodevelopmental disorders with moderately strong genetic components and lifelong implications. RD and LI are marked by unexpected difficulty acquiring and processing written and verbal language, respectively, despite adequate opportunity and instruction. RD and LI-and their associated deficits-are complex, multifactorial, and often comorbid. Genetic studies have repeatedly implicated the DYX2 locus, specifically the genes DCDC2 and KIAA0319, in RD, with recent studies suggesting they also influence LI, verbal language, and cognition. Here, we characterize the relationship of the DYX2 locus with RD, LI, and IQ. To accomplish this, we developed a marker panel densely covering the 1.4 Mb DYX2 locus and assessed association with reading, language, and IQ measures in subjects from the Avon Longitudinal Study of Parents and Children. We then replicated associations in three independent, disorder-selected cohorts. As expected, there were associations with known RD risk genes KIAA0319 and DCDC2. In addition, we implicated markers in or near other DYX2 genes, including TDP2, ACOT13, C6orf62, FAM65B, and CMAHP. However, the LD structure of the locus suggests that associations within TDP2, ACOT13, and C6orf62 are capturing a previously reported risk variant in KIAA0319. Our results further substantiate the candidacy of KIAA0319 and DCDC2 as major effector genes in DYX2, while proposing FAM65B and CMAHP as new DYX2 candidate genes. Association of DYX2 with multiple neurobehavioral traits suggests risk variants have functional consequences affecting multiple neurological processes. Future studies should dissect these functional, possibly interactive relationships of DYX2 candidate genes.

Longitudinal speech perception and language performance in pediatric cochlear implant users: the effect of age at implantation.

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.

The development of real-time spoken and word recognition derives from changes in ability, not maturation.

In typical adults, recognizing both spoken and written words is thought to be served by a process of competition between candidates in the lexicon. In recent years, work has used eye-tracking in the visual world paradigm to characterize this competition process over development. It has shown that both spoken and written word recognition continue to develop through adolescence (Rigler et al., 2015). It is still unclear what drives these changes in real-time word recognition over the school years, as there are dramatic changes in language, the onset of reading instruction, and gains in domain general function during this time. This study began to address these issues by asking whether changes in real-time word recognition derive from changes in overall language and reading ability or reflect more general age-related development. This cross-sectional study examined 278 school-age children (Grades 1-3) using the Visual World Paradigm to assess both spoken and written word recognition, along with multiple measures of language, reading and phonology. A structural equation model applied to these ability measures found three factors representing language, reading, and phonology. Multiple regression analyses were used to understand how these three factors relate to real-time spoken and written word recognition as well as a non-linguistic variant of the VWP intended to capture decision speed, eye-movement factors, and other non-language/reading differences. We found that for both spoken and written word recognition, the speed of activating target words in both domains was more closely tied to the relevant ability (e.g., reading for written word recognition) than was age. We also examined competition resolution (how fully competitors were suppressed late in processing). Here, spoken word recognition showed only small, developmental effects that were only related to phonological processing, suggesting links to developmental language disorder. However, in written word recognition, competitor resolution showed large impacts of development which were strongly linked to reading. This suggests the dimensionality of real-time lexical processing may differ across domains. Importantly, neither spoken nor written word recognition is fully described by changes in non-linguistic skills assessed with non-linguistic VWP, and the non-linguistic VWP was linked to differences in language and reading. These findings suggest that spoken and written word recognition continue past the first year of life and are mostly driven by ability and not only by overall maturation.

Lingo: an automated, web-based deep phenotyping platform for language ability.

Background: Language and the ability to communicate effectively are key factors in mental health and well-being. Despite this critical importance, research on language is limited by the lack of a scalable phenotyping toolkit. Methods: Here, we describe and showcase Lingo - a flexible online battery of language and nonverbal reasoning skills based on seven widely used tasks (COWAT, picture narration, vocal rhythm entrainment, rapid automatized naming, following directions, sentence repetition, and nonverbal reasoning). The current version of Lingo takes approximately 30 minutes to complete, is entirely open source, and allows for a wide variety of performance metrics to be extracted. We asked > 1,300 individuals from multiple samples to complete Lingo, then investigated the validity and utility of the resulting data. Results: We conducted an exploratory factor analysis across 14 features derived from the seven assessments, identifying five factors. Four of the five factors showed acceptable test-retest reliability (Pearson's R > 0.7). Factor 2 showed the highest reliability (Pearson's R = 0.95) and loaded primarily on sentence repetition task performance. We validated Lingo with objective measures of language ability by comparing performance to gold-standard assessments: CELF-5 and the VABS-3. Factor 2 was significantly associated with the CELF-5 "core language ability" scale (Pearson's R = 0.77, p-value < 0.05) and the VABS-3 "communication" scale (Pearson's R = 0.74, p-value < 0.05). Factor 2 was positively associated with phenotypic and genetic measures of socieconomic status. Interestingly, we found the parents of children with language impairments had lower Factor 2 scores (p-value < 0.01). Finally, we found Lingo factor scores were significantly predictive of numerous psychiatric and neurodevelopmental conditions. Conclusions: Together, these analyses support Lingo as a powerful platform for scalable deep phenotyping of language and other cognitive abilities. Additionally, exploratory analyses provide supporting evidence for the heritability of language ability and the complex relationship between mental health and language.

Acquisition of tense marking in English-speaking children with cochlear implants: a longitudinal study.

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.

Understanding language processing in variable populations on their own terms: Towards a functionalist psycholinguistics of individual differences, development, and disorders.

Classic psycholinguistics seeks universal language mechanisms for all people, emphasing the "modal" listener: hearing, neurotypical, monolingual, young adults. Applied psycholinguistics then characterizes differences in terms of their deviation from modal. This mirrors naturalist philosophies of health which presume a normal function, with illness as a deviation. In contrast, normative positions argue that illness is partially culturally derived. It occurs when a person cannot meet socio-culturally defined goals, separating differences in biology (disease) from socio-cultural function (illness). We synthesize this with mechanistic functionalist views in which language emerges from diverse lower level mechanisms with no one-to-one mapping to function (termed the functional mechanistic normative approach). This challenges primarily psychometric approaches-which are culturally defined-suggesting a process-based approach may yield more insight. We illustrate this with work on word recognition across multiple domains: cochlear implant users, children, language disorders, L2 learners, and aging. This work investigates each group's solutions to the problem of word recognition as interesting in its own right. Variation in process is value-neutral, and psychometric measures complement this, reflecting fit with cultural expectations (disease vs. illness). By examining variation in processing across people with a variety of skills and goals, we arrive at deeper insight into fundamental principles.

The aromatase gene CYP19A1: several genetic and functional lines of evidence supporting a role in reading, speech and language.

Inspired by the localization, on 15q21.2 of the CYP19A1 gene in the linkage region of speech and language disorders, and a rare translocation in a dyslexic individual that was brought to our attention, we conducted a series of studies on the properties of CYP19A1 as a candidate gene for dyslexia and related conditions. The aromatase enzyme is a member of the cytochrome P450 super family, and it serves several key functions: it catalyzes the conversion of androgens into estrogens; during early mammalian development it controls the differentiation of specific brain areas (e.g. local estrogen synthesis in the hippocampus regulates synaptic plasticity and axonal growth); it is involved in sexual differentiation of the brain; and in songbirds and teleost fishes, it regulates vocalization. Our results suggest that variations in CYP19A1 are associated with dyslexia as a categorical trait and with quantitative measures of language and speech, such as reading, vocabulary, phonological processing and oral motor skills. Variations near the vicinity of its brain promoter region altered transcription factor binding, suggesting a regulatory role in CYP19A1 expression. CYP19A1 expression in human brain correlated with the expression of dyslexia susceptibility genes such as DYX1C1 and ROBO1. Aromatase-deficient mice displayed increased cortical neuronal density and occasional cortical heterotopias, also observed in Robo1-/- mice and human dyslexic brains, respectively. An aromatase inhibitor reduced dendritic growth in cultured rat neurons. From this broad set of evidence, we propose CYP19A1 as a candidate gene for human cognitive functions implicated in reading, speech and language.

Prevalence and Nature of Late-Emerging Poor Readers.

Some children demonstrate adequate or better reading achievement in early school grades, but fall significantly behind their peers in later grades. These children are often referred to as late-emerging poor readers. In this study, we investigated the prevalence and heterogeneity of these poor readers. We also examined the early language and nonverbal cognitive abilities of late-emerging poor readers. Participants were 493 children who were a subsample from an epidemiological study of language impairments in school-age children. In kindergarten, children were administered a battery of language, early literacy, and nonverbal cognitive measures. Word reading and reading comprehension achievement was assessed in second, fourth, eighth, and tenth grades. Latent transition analysis was used to model changes in reading classification (good vs. poor reader) across grades. Population estimates revealed that 13.4% percent of children could be classified as late-emerging poor readers. These children could be divided into those with problems in comprehension alone (52%), word reading alone (36%), or both (12%). Further results indicated that late-emerging poor readers often had a history of language and/or nonverbal cognitive impairments in kindergarten. Subtypes of poor readers also differed significantly in their profiles of language, early literacy, and nonverbal cognitive abilities in kindergarten. Results are discussed in terms of causal factors and implications for early identification.

Growing up with a cochlear implant: education, vocation, and affiliation.

The long-term educational/vocational, affiliation, and quality-of-life outcomes of the first and second cohorts of children with bilateral, profound hearing loss who received cochlear implants under a large National Institutes of Health-funded study was investigated in 41 of 61 eligible participants. Educational and vocational outcomes were collected from user survey data. Affiliation and quality-of-life data were collected from the Satisfaction-with-Life scale and the Deaf Identity Scale. Qualitative results indicated that compared with their hearing, adult-age peers, this group obtained high educational achievement, and they reported a very high satisfaction of life. With respect to forming an identity in these first 2 cohorts of cochlear implant users, we found that most of the individuals endorsed a dual identity, which indicates they feel just as comfortable with Deaf individuals as they do with hearing individuals. Quantitative results revealed a significant relationship between ability to hear and ability to speak, in addition to consistency of device use. Additional relationships were found between mother's and the individual's educational statuses, hearing scores, and communication system used. Younger individuals scored higher on satisfaction-with-life measures, and they also tended to endorse a dual identity more often. Taken together, these findings diminish concerns that profoundly deaf individuals growing up with cochlear implants will become culturally bereft and unable to function in the hearing world.