A set of regulatory genes co-expressed in embryonic human brain is implicated in disrupted speech development.

Genetic investigations of people with impaired development of spoken language provide windows into key aspects of human biology. Over 15 years after FOXP2 was identified, most speech and language impairments remain unexplained at the molecular level. We sequenced whole genomes of nineteen unrelated individuals diagnosed with childhood apraxia of speech, a rare disorder enriched for causative mutations of large effect. Where DNA was available from unaffected parents, we discovered de novo mutations, implicating genes, including CHD3, SETD1A and WDR5. In other probands, we identified novel loss-of-function variants affecting KAT6A, SETBP1, ZFHX4, TNRC6B and MKL2, regulatory genes with links to neurodevelopment. Several of the new candidates interact with each other or with known speech-related genes. Moreover, they show significant clustering within a single co-expression module of genes highly expressed during early human brain development. This study highlights gene regulatory pathways in the developing brain that may contribute to acquisition of proficient speech.

Introduction: Motor Speech Disorders in Idiopathic Speech Delay and in Complex Neurodevelopmental Disorders: Introduction.

This introduction to a special issue of Clinical Linguistics & Phonetics includes an overview of the contents of each of the six articles. Each of the articles use the finalized version of the Speech Disorders Classification System (SDCS).

A frequent acoustic sign of speech motor delay (SMD).

Recent studies report prevalence, phenotype, and persistence findings for a paediatric motor speech disorder in addition to childhood dysarthria and childhood apraxia of speech termed Speech Motor Delay (SMD). The aim of the present study was to determine if there is a frequent acoustic sign of SMD, with implications for theory, assessment, and treatment. We examined the frequency of 19 acoustic signs of SMD in audio recordings of continuous speech and word-imitation tasks in three groups of speakers with SMD: 50 children (mean age 5.1 years) with idiopathic Speech Delay (SD) from 6 USA cities; 87 children, adolescents, and adults with eight types of complex neurodevelopmental disorders; and 9 children (mean age 8.8 years) with persistent idiopathic SD from a population-based study of children in the South West of England. The 19 acoustic signs of imprecise or unstable speech, prosody, and voice were standardized on typical speakers of the appropriate dialect. The criterion for a frequent acoustic sign was that it occurred in at least 50% of participants with SMD in each of the three groups. Findings indicated that lengthened mid-vowels and diphthongs was the one sign that met criteria, occurring in 64.4% of the 146 participants with SMD, including 71% of the 87 participants with complex neurodevelopmental disorders. Findings are interpreted to support the potential of this acoustic sign, and possibly several others associated with temporal dimensions of speech sound development, to inform explication of the neuromotor substrates of SMD.

Estimates of the prevalence of speech and motor speech disorders in adolescents with Down syndrome.

Although there is substantial rationale for a motor component in the speech of persons with Down syndrome (DS), there presently are no published estimates of the prevalence of subtypes of motor speech disorders in DS. The goal of this research is to provide initial estimates of the prevalence of types of speech disorders and motor speech disorders in adolescents with DS. Conversational speech samples from a convenience sample of 45 adolescents with DS, ages 10 to 20 years old, were analysed using perceptual and acoustic methods and measures in the Speech Disorders Classification System (SDCS). The SDCS cross-classified participants into five mutually exclusive speech classifications and five mutually exclusive motor speech classifications. For participants meeting criteria for Childhood Dysarthria or for Childhood Dysarthria concurrent with Childhood Apraxia of Speech, the SDCS provided information on participants' percentile status on five subtypes of dysarthria. A total of 97.8% of participants met SDCS criteria for Speech Disorders and 97.8% met criteria for Motor Speech Disorders, including Childhood Dysarthria (37.8%), Speech Motor Delay (26.7%), Childhood Dysarthria and Childhood Apraxia of Speech (22.2%), and Childhood Apraxia of Speech (11.1%). Ataxia was the most prevalent dysarthria subtype. Nearly all participants with DS in the present sample had some type of speech and motor speech disorder, with implications for theory, assessment, prediction, and treatment. Specific to treatment, the present findings are interpreted as support for motor speech disorders as a primary explanatory construct to guide the selection and sequencing of treatment targets for persons with DS. Abbreviations: CAS: Childhood Apraxia of Speech; CD: Childhood Dysarthria; DS: Down syndrome; NSA: Normal(ized) Speech Acquisition; PSD: Persistent Speech Delay; PSE: Persistent Speech Errors; SD: Speech Delay; SDCS: Speech Disorders Classification System; SE: Speech Errors; SMD: Speech Motor Delay.

Speech and motor speech disorders and intelligibility in adolescents with Down syndrome.

The goal of this research was to assess the support for motor speech disorders as explanatory constructs to guide research and treatment of reduced intelligibility in persons with Down syndrome (DS). Participants were the 45 adolescents with DS in the prior paper who were classified into five mutually-exclusive motor speech classifications using the Speech Disorders Classification System. An ordinal index classified participants' percentage of intelligible words in conversation as High (≥ 85%), Moderate (80% - 84.9%), or Low (< 80%). Statistical analyses tested for significant differences in intelligibility status associated with demographic, intelligence, and language variables, and intelligibility status associated with motor speech classifications and speech, prosody, and voice variables. For the 10 participants who met criteria for concurrent Childhood Dysarthria and Childhood Apraxia of Speech at assessment, 80% had reduced (Moderate or Low) intelligibility and 20% had High intelligibility (significant effect size: 0.644). Proportionally more of the 32 participants who met criteria for either dysarthria or apraxia had reduced intelligibility (significant effect size: 0.318). Low intelligibility was significantly associated with across-the-board reductions in phonemic and phonetic accuracy and with inappropriate prosody and voice. Findings are interpreted as support for motor speech disorders in adolescents with DS as explanatory constructs for their reduced intelligibility. Pending cross-validation of findings in diverse samples of persons with DS, studies are needed to assess the efficacy of motor speech classification status to guide selection of treatment methods and intelligibility targets. Abbreviations: CAS: Childhood Apraxia of Speech; CD: Childhood Dysarthria; DS: Down syndrome; II: Intelligibility Index; No MSD: No Motor Speech Disorder; OII: Ordinal Intelligibility Index; PSD: Persistent Speech Delay; SDCS: Speech Disorders Classification System; SMD: Speech Motor Delay.

Estimates of the prevalence of motor speech disorders in children with idiopathic speech delay.

The goal of this research was to obtain initial estimates of the prevalence of each of four types of motor speech disorders in children with idiopathic Speech Delay (SD) and to use findings to estimate the population-based prevalence of each disorder. Analyses were completed on audio-recorded conversational speech samples from 415 children recruited for research in idiopathic SD in six USA cities during the past three decades. The speech and motor speech status of each participant was cross-classified using standardized measures in the finalized version of the Speech Disorders Classification System described in the Supplement. Population-based prevalence estimates for the four motor speech disorders were calculated from epidemiological studies of SD conducted in Australia, England, and the USA. A total of 82.2% of the 415 participants with SD met criteria for No Motor Speech Disorder at assessment, 12% met criteria for Speech Motor Delay, 3.4% met criteria for Childhood Dysarthria, 2.4% met criteria for Childhood Apraxia of Speech, and 0% met criteria for concurrent Childhood Dysarthria and Childhood Apraxia of Speech. The estimated population-based prevalence of each of the first three motor speech disorders at 4 to 8 years of age were Speech Motor Delay: 4 children per 1,000; Childhood Dysarthria: 1 child per 1,000; and Childhood Apraxia of Speech: 1 child per 1,000. The latter finding cross-validates a prior prevalence estimate for Childhood Apraxia of Speech of 1-2 children per 1,000. Findings are interpreted to indicate a substantial prevalence of motor speech disorders in children with idiopathic SD. Abbreviations: CAS, childhood apraxia of speech; CD, childhood dysarthria; CND, complex neurodevelopmental disorders; DI, dysarthria index; DSI, dysarthria subtype indices; MSD, motor speech disorder; No MSD, no motor speech disorder; NSA, normal(ized) speech acquisition; PEPPER, programs to examine phonetic and phonologic evaluation records; PM, pause marker; PMI, pause marker index; PSD, persistent speech delay; PSE, persistent speech errors; SD, speech delay; SDCS, speech disorders classification system; SDCSS, speech disorders classification system summary; SE, speech errors; SMD, speech motor delay.

Initial studies of the phenotype and persistence of speech motor delay (SMD).

Speech Motor Delay (SMD) is a recently proposed childhood motor speech disorder characterized by imprecise and unstable speech, prosody, and voice that does not meet criteria for either Childhood Dysarthria or Childhood Apraxia of Speech. The goals of the present research were to obtain information on the phenotype of SMD and initial information on the persistence of SMD in children receiving treatment for idiopathic Speech Delay (SD). Five questions about the phenotype and persistence of SMD were posed using a database of audio-recordings and participant records and longitudinal data from audio-recordings of children with early SMD treated for SD. Three phenotype questions examined associations between participant risk factors and prevalence of SMD, and described the most frequent speech, prosody, and voice signs of early SMD. To provide initial estimates of the persistence of SMD, two questions examined associations between the persistence of SMD and participant risk factors using the audio-recordings of 14 participants with SMD treated for idiopathic SD. Phenotype findings indicated that SMD is characterized by across-the-board delays in the spatiotemporal precision and stability of speech, prosody, and voice production. Persistence findings indicated that although most participants normalized early SMD by 6 years of age, SMD persisted until at least late adolescence in 21.4% of participants. Findings are interpreted to support the construct validity of SMD and the potential for research using additional assessment modalities to explicate its genomic and neuromotor causal pathways. Abbreviations: CAS: Childhood Apraxia of Speech; CD: Childhood Dysarthria; MSD: Motor Speech Disorder; No MSD: No Motor Speech Disorder; PSI: Precision-Stability Index; SD: Speech Delay; SMD: Speech Motor Delay; SSD: Speech Sound Disorders.

Estimates of the prevalence of speech and motor speech disorders in persons with complex neurodevelopmental disorders.

Estimates of the prevalence of speech and motor speech disorders in persons with complex neurodevelopmental disorders (CND) can inform research in the biobehavioural origins and treatment of CND. The goal of this research was to use measures and analytics in a diagnostic classification system to estimate the prevalence of speech and motor speech disorders in convenience samples of speakers with one of eight types of CND. Audio-recorded conversational speech samples from 346 participants with one of eight types of CND were obtained from a database of participants recruited for genetic and behavioural studies of speech sound disorders (i.e., excluding dysfluency) during the past three decades. Data reduction methods for the speech samples included narrow phonetic transcription, prosody-voice coding, and acoustic analyses. Standardized measures were used to cross-classify participants' speech and motor speech status. Compared to the 17.8% prevalence of four types of motor speech disorders reported in a study of 415 participants with idiopathic Speech Delay (SD), 47.7% of the present participants with CND met criteria for one of four motor speech disorders, including Speech Motor Delay (25.1%), Childhood Dysarthria (13.3%), Childhood Apraxia of Speech (4.3%), and concurrent Childhood Dysarthria and Childhood Apraxia of Speech (4.9%). Findings are interpreted to indicate a substantial prevalence of speech disorders, and notably, a substantial prevalence of motor speech disorders in persons with some types of CND. We suggest that diagnostic classification information from standardized motor speech assessment protocols can contribute to research in the pathobiologies of CND. Abbreviations: 16p: 16p11.2 deletion and duplication syndrome; 22q: 22q11.2 deletion syndrome; ASD: Autism Spectrum Disorder; CAS: Childhood Apraxia of Speech; CD: Childhood Dysarthria; CND: Complex Neurodevelopmental Disorder; DS: Down syndrome; FXS: Fragile X syndrome; GAL: Galactosemia; IID: Idiopathic Intellectual Disability; MSD: Motor Speech Disorder; No MSD: No Motor Speech Disorder; NSA: Normal(ized) Speech Acquisition; PEPPER: Programs to Examine Phonetic and Phonologic Evaluation Records; PSD: Persistent Speech Delay; PSE: Persistent Speech Errors; SD: Speech Delay; SDCS: Speech Disorders Classification System; SDCSS: Speech Disorders Classification System Summary; SE: Speech Errors; SMD: Speech Motor Delay; SSD: Speech Sound Disorders; TBI: Traumatic Brain Injury.

Distinct developmental profiles in typical speech acquisition.

Three- to five-year-old children produce speech that is characterized by a high level of variability within and across individuals. This variability, which is manifest in speech movements, acoustics, and overt behaviors, can be input to subgroup discovery methods to identify cohesive subgroups of speakers or to reveal distinct developmental pathways or profiles. This investigation characterized three distinct groups of typically developing children and provided normative benchmarks for speech development. These speech development profiles, identified among 63 typically developing preschool-aged speakers (ages 36-59 mo), were derived from the children's performance on multiple measures. These profiles were obtained by submitting to a k-means cluster analysis of 72 measures that composed three levels of speech analysis: behavioral (e.g., task accuracy, percentage of consonants correct), acoustic (e.g., syllable duration, syllable stress), and kinematic (e.g., variability of movements of the upper lip, lower lip, and jaw). Two of the discovered group profiles were distinguished by measures of variability but not by phonemic accuracy; the third group of children was characterized by their relatively low phonemic accuracy but not by an increase in measures of variability. Analyses revealed that of the original 72 measures, 8 key measures were sufficient to best distinguish the 3 profile groups.

Novel candidate genes and regions for childhood apraxia of speech identified by array comparative genomic hybridization.

PURPOSE: The goal of this study was to identify new candidate genes and genomic copy-number variations associated with a rare, severe, and persistent speech disorder termed childhood apraxia of speech. Childhood apraxia of speech is the speech disorder segregating with a mutation in FOXP2 in a multigenerational London pedigree widely studied for its role in the development of speech-language in humans. METHODS: A total of 24 participants who were suspected to have childhood apraxia of speech were assessed using a comprehensive protocol that samples speech in challenging contexts. All participants met clinical-research criteria for childhood apraxia of speech. Array comparative genomic hybridization analyses were completed using a customized 385K Nimblegen array (Roche Nimblegen, Madison, WI) with increased coverage of genes and regions previously associated with childhood apraxia of speech. RESULTS: A total of 16 copy-number variations with potential consequences for speech-language development were detected in 12 or half of the 24 participants. The copy-number variations occurred on 10 chromosomes, 3 of which had two to four candidate regions. Several participants were identified with copy-number variations in two to three regions. In addition, one participant had a heterozygous FOXP2 mutation and a copy-number variation on chromosome 2, and one participant had a 16p11.2 microdeletion and copy-number variations on chromosomes 13 and 14. CONCLUSION: Findings support the likelihood of heterogeneous genomic pathways associated with childhood apraxia of speech.

Phenotype of FOXP2 haploinsufficiency in a mother and son.

Disruptions in FOXP2, a transcription factor, are the only known monogenic cause of speech and language impairment. We report on clinical findings for two new individuals with a submicroscopic deletion of FOXP2: a boy with severe apraxia of speech and his currently moderately affected mother. A 1.57 Mb deletion on chromosome 7q31 was detected by array comparative genomic hybridization (aCGH). In addition to FOXP2, the patients' deletion involves two other genes, MDFIC and PPP1R3A, neither of which has been associated with speech or language disorders. Thus, findings for these two family members provide informative phenotypic information on FOXP2 haploinsufficiency. Evaluation by a clinical geneticist indicated no major congenital anomalies or dysmorphic features. Evaluations by a clinical psychologist and occupational therapist indicated cognitive-linguistic processing and sensorimotor control deficits, but did not support a diagnosis of autism spectrum disorder. Evaluation by clinical and research speech pathologists confirmed that both patients' speech deficits met contemporary criteria for apraxia of speech. Notably, the patients were not able to laugh, cough, or sneeze spontaneously, replicating findings reported for two other FOXP2 cases and a potential diagnostic sign of nonsyndromic apraxia of speech. Speech severity findings for the boy were not consistent with the hypothesis that loss of maternal FOXP2 should be relatively benign. Better understanding of the behavioral phenotype of FOXP2 disruptions will aid identification of patients, toward an eventual understanding of the pathophysiology of syndromic and nonsyndromic apraxia of speech.

Encoding, memory, and transcoding deficits in Childhood Apraxia of Speech.

A central question in Childhood Apraxia of Speech (CAS) is whether the core phenotype is limited to transcoding (planning/programming) deficits or if speakers with CAS also have deficits in auditory-perceptual encoding (representational) and/or memory (storage and retrieval of representations) processes. We addressed this and other questions using responses to the Syllable Repetition Task (SRT) [Shriberg, L. D., Lohmeier, H. L., Campbell, T. F., Dollaghan, C. A., Green, J. R., & Moore, C. A. (2009). A nonword repetition task for speakers with misarticulations: The syllable repetition task (SRT). Journal of Speech, Language, and Hearing Research, 52, 1189-1212]. The SRT was administered to 369 individuals in four groups: (a) typical speech-language (119), (b) speech delay-typical language (140), (c) speech delay-language impairment (70), and (d) idiopathic or neurogenetic CAS (40). CAS participants had significantly lower SRT competence, encoding, memory, and transcoding scores than controls. They were 8.3 times more likely than controls to have SRT transcoding scores below 80%. We conclude that speakers with CAS have speech processing deficits in encoding, memory, and transcoding. The SRT currently has moderate diagnostic accuracy to identify transcoding deficits, the signature feature of CAS.

Heritability estimation for speech-sound traits with developmental trajectories.

Numerous studies have examined genetic influences on developmental problems such as speech sound disorders (SSD), language impairment (LI), and reading disability. Disorders such as SSD are often analyzed using their component endophenotypes. Most studies, however, have involved comparisons of twin pairs or siblings of similar age, or have adjusted for age ignoring effects that are peculiar to age-related trajectories for phenotypic change. Such developmental changes in these skills have limited the usefulness of data from parents or siblings who differ substantially in age from the probands. Employing parent-offspring correlation in heritability estimation permits a more precise estimate of the additive component of genetic variance, but different generations have to be measured for the same trait. We report on a smoothing procedure which fits a series of lines that approximate a curve matching the developmental trajectory. This procedure adjusts for changes in measures with age, so that the adjusted values are on a similar scale for children, adolescents, and adults. We apply this method to four measures of phonological memory and articulation in order to estimate their heritability. Repetition of multisyllabic real words (MSW) showed the best heritability estimate of 45% in this sample. We conclude that differences in measurement scales across the age span can be reconciled through non-linear modeling of the developmental process.

Extensions to the Speech Disorders Classification System (SDCS).

This report describes three extensions to a classification system for paediatric speech sound disorders termed the Speech Disorders Classification System (SDCS). Part I describes a classification extension to the SDCS to differentiate motor speech disorders from speech delay and to differentiate among three sub-types of motor speech disorders. Part II describes the Madison Speech Assessment Protocol (MSAP), an ∼ 2-hour battery of 25 measures that includes 15 speech tests and tasks. Part III describes the Competence, Precision, and Stability Analytics (CPSA) framework, a current set of ∼ 90 perceptual- and acoustic-based indices of speech, prosody, and voice used to quantify and classify sub-types of Speech Sound Disorders (SSD). A companion paper provides reliability estimates for the perceptual and acoustic data reduction methods used in the SDCS. The agreement estimates in the companion paper support the reliability of SDCS methods and illustrate the complementary roles of perceptual and acoustic methods in diagnostic analyses of SSD of unknown origin. Examples of research using the extensions to the SDCS described in the present report include diagnostic findings for a sample of youth with motor speech disorders associated with galactosemia, and a test of the hypothesis of apraxia of speech in a group of children with autism spectrum disorders. All SDCS methods and reference databases running in the PEPPER (Programs to Examine Phonetic and Phonologic Evaluation Records) environment will be disseminated without cost when complete.

Perceptual and acoustic reliability estimates for the Speech Disorders Classification System (SDCS).

A companion paper describes three extensions to a classification system for paediatric speech sound disorders termed the Speech Disorders Classification System (SDCS). The SDCS uses perceptual and acoustic data reduction methods to obtain information on a speaker's speech, prosody, and voice. The present paper provides reliability estimates for the two perceptual methods (narrow phonetic transcription; prosody-voice coding) and the acoustic analysis methods the SDCS uses to describe and classify a speaker's speech competence, precision, and stability. Speech samples from 10 speakers, five with significant motor speech disorder and five with typical speech, were re-measured to estimate intra-judge and inter-judge agreement for the perceptual and acoustic methods. Each of the speakers completed five speech tasks (total = 50 datasets), ranging in articulatory difficulty for the speakers, with consequences for the difficulty level of data reduction. Point-to-point percentage of agreement findings for the two perceptual methods were as high or higher than reported in literature reviews and from previous studies conducted within the laboratory. Percentage of agreement findings for the acoustics tasks of segmenting phonemes, editing fundamental frequency tracks, and estimating formants ranged from values in the mid 70% to 100%, with most estimates in the mid 80% to mid 90% range. Findings are interpreted as support for the perceptual and acoustic methods used in the SDCS to describe and classify speakers with speech sound disorders.

What influences literacy outcome in children with speech sound disorder?

PURPOSE: In this study, the authors evaluated literacy outcome in children with histories of speech sound disorder (SSD) who were characterized along 2 dimensions: broader language function and persistence of SSD. In previous studies, authors have demonstrated that each dimension relates to literacy but have not disentangled their effects. Methods Two groups of children (86 SSD and 37 controls) were recruited at ages 5-6 and were followed longitudinally. The authors report the literacy of children with SSD at ages 7-9, compared with controls and national norms, and relative to language skill and SSD persistence (both measured at age 5-6). RESULTS: The SSD group demonstrated elevated rates of reading disability. Language skill but not SSD persistence predicted later literacy. However, SSD persistence was associated with phonological awareness impairments. Phonological awareness alone predicted literacy outcome less well than a model that also included syntax and nonverbal IQ. CONCLUSIONS: Results support previous literature findings that SSD history predicts literacy difficulties and that the association is strongest for SSD + language impairment (LI). Magnitude of phonological impairment alone did not determine literacy outcome, as predicted by the core phonological deficit hypothesis. Instead, consistent with a multiple deficit approach, phonological deficits appeared to interact with other cognitive factors in literacy development.

A nonword repetition task for speakers with misarticulations: the Syllable Repetition Task (SRT).

PURPOSE: Conceptual and methodological confounds occur when non(sense) word repetition tasks are administered to speakers who do not have the target speech sounds in their phonetic inventories or who habitually misarticulate targeted speech sounds. In this article, the authors (a) describe a nonword repetition task, the Syllable Repetiton Task (SRT), that eliminates this confound and (b) report findings from 3 validity studies. METHOD: Ninety-five preschool children with speech delay and 63 with typical speech completed an assessment battery that included the Nonword Repetition Task (NRT; C. Dollaghan & T. F. Campbell, 1998) and the SRT. SRT stimuli include only 4 of the earliest occurring consonants and 1 early occurring vowel. RESULTS: Study 1 findings indicated that the SRT eliminated the speech confound in nonword testing with speakers who misarticulate. Study 2 findings indicated that the accuracy of the SRT to identify expressive language impairment was comparable to findings for the NRT. Study 3 findings illustrated the SRT's potential to interrogate speech processing constraints underlying poor nonword repetition accuracy. Results supported both memorial and auditory-perceptual encoding constraints underlying nonword repetition errors in children with speech-language impairment. CONCLUSION: The SRT appears to be a psychometrically stable and substantively informative nonword repetition task for emerging genetic research and other research with speakers who misarticulate.

Language features in a mother and daughter of a chromosome 7;13 translocation involving FOXP2.

PURPOSE: The aims of this study were (a) to locate the breakpoints of a balanced translocation (7;13) within a mother (B) and daughter (T); (b) to describe the language and cognitive skills of B and T; and (c) to compare this profile with affected family members of the KE family who have a mutation within FOXP2. METHOD: The breakpoint locations for T and B were identified by use of fluorescent in situ hybridization analysis followed by DNA sequencing using long-range polymer chain reaction amplification methods. The cognitive and language characteristics were obtained via the use of standardized tests of intelligence, receptive and expressive vocabulary and sentence use, and a spontaneous language sample. RESULTS: The translocation breakpoints in T and B were found in FOXP2 on chromosome 7 and in RFC3 on chromosome 13. T and B's pattern of relative strengths and weaknesses across their cognitive and language performance was found to be similar to descriptions of the affected KE family members. CONCLUSIONS: Prior reports of individuals with chromosomal rearrangements of FOXP2 have emphasized their speech impairment. This study provides additional evidence that language-in particular, grammar-is likely to be influenced by abnormalities of FOXP2 function.

Estimates of the Prevalence of Speech and Motor Speech Disorders in Youth With 22q11.2 Deletion Syndrome.

Purpose Speech sound disorders and velopharyngeal dysfunction are frequent features of 22q11.2 deletion syndrome (22q). We report the first estimate of the prevalence of motor speech disorders (MSDs) in youth with 22q. Method Seventeen children and adolescents with 22q completed an assessment protocol that included a conversational speech sample. Data reduction included phonetic transcription, perceptual speech ratings, prosody-voice coding, and acoustic analyses. Data analyses included 3 motor speech measures and a cross-classification analytic. Prevalence estimates of speech and MSDs in youth with 22q were compared with estimates in speakers with other complex neurodevelopmental disorders: Down syndrome, fragile X syndrome, and galactosemia. Results Results indicated that 58.8% of the participants with 22q met criteria for speech delay, and 82.4% of the participants met criteria for MSDs, including 29.4% with speech motor delay, 29.4% with childhood dysarthria, 11.8% with childhood apraxia of speech, and 11.8% with concurrent childhood dysarthria and childhood apraxia of speech. MSDs were not significantly associated with velopharyngeal dysfunction. Conclusions In summary, 82.4% of the participants with 22q met criteria for 1 of 4 MSDs, predominantly speech motor delay and childhood dysarthria. Cross-validation of the present findings would support viewing MSDs as a core phenotypic feature of 22q.

Which children benefit from letter names in learning letter sounds?

Typical U.S. children use their knowledge of letters' names to help learn the letters' sounds. They perform better on letter sound tests with letters that have their sounds at the beginnings of their names, such as v, than with letters that have their sounds at the ends of their names, such as m, and letters that do not have their sounds in their names, such as h. We found this same pattern among children with speech sound disorders, children with language impairments as well as speech sound disorders, and children who later developed serious reading problems. Even children who scored at chance on rhyming and sound matching tasks performed better on the letter sound task with letters such as v than with letters such as m and h. Our results suggest that a wide range of children use the names of letters to help learn the sounds and that phonological awareness, as conventionally measured, is not required in order to do so.