A comparison of phonological skills of boys with fragile X syndrome and Down syndrome

Perceptual and acoustic predictors of speech intelligibility among Hebrew-speaking young adults with down syndrome

BACKGROUND

Down syndrome (DS) is a common chromosomal disorder associated with various speech impairments, including reduced intelligibility. While speech subsystem deficits in DS have been documented, their relative influence on intelligibility remains understudied, particularly in non-English speaking populations. This study investigated speech intelligibility and select subsystem functioning in Hebrew-speaking young adults with DS, aiming to describe the speech production disorder and identify predictors of single-word intelligibility in this population.

METHODS

Twenty-four adults with DS and 24 typically developing (TD) peers produced common single words in Hebrew. Perceptual and acoustic analyses were conducted on select speech subsystems, including articulatory (consonant and vowel production) and phonatory measures.

RESULTS

Speakers with DS had higher error rates for complex consonants and demonstrated vowel space centralization compared to TD peers. Group differences were observed in most acoustic vowel measures, with interactions with speaker gender, but only select acoustic voice measures. Stepwise regression analysis identified three significant predictors of single-word intelligibility in the DS group, namely Percentage of Consonants Correct (PCC), Jitter (ppq), and average ellipse size of vowel clusters within the acoustic vowel space.

CONCLUSIONS

These findings highlight the complex nature of speech intelligibility deficits in individuals with DS, emphasizing both articulatory and phonatory contributing factors. The results also suggest potential cross-linguistic differences in subsystem contributions to intelligibility. Clinical implications include the need for comprehensive assessment and targeted interventions addressing multiple speech subsystems in this population.

The Contribution of FMRP to the Development of Speech and Vocabulary in Young Boys with Fragile X Syndrome: A Retrospective Examination

BACKGROUND/OBJECTIVES

This study examined the development of speech, expressive vocabulary, and receptive vocabulary in boys with Fragile X Syndrome (FXS), with a focus on the contribution of the Fragile X Messenger Ribonucleoprotein (FMRP), while controlling for the effects of nonverbal IQ, maternal education, and Autism status on the development of these skills.

METHODS

Participants included 45 boys with full mutation FXS, ranging in age from 2.9 to 14.0 years, who were subdivided into those with FXS only (FXS-Only) and those with FXS and Autism (FXS-Autism). Speech, expressive vocabulary, and receptive vocabulary skills were assessed over three years for each participant.

RESULTS

There was a significant relationship between each of the outcome measures and the child's nonverbal mental level, and between for both outcome measures of vocabulary and Autism status, but these relationships were moderated by the level of FMRP. Specifically, higher levels of FMRP seemed to increase the relationship between developmental level of speech, receptive, and expressive vocabulary for boys with FXS with and without Autism; however, at lower levels of FMRP, these relationships seemed to weaken significantly for both groups.

CONCLUSIONS

These findings implicate increased complexity in the relationship between various contributors to the rates of growth of speech, expressive vocabulary, and receptive vocabulary in boys with FXS, with FMRP being a key variable potentially moderating the relationship between nonverbal abilities, Autism status, and speech and vocabulary development.

Talkitt: toward a new instrument based on artificial intelligence for augmentative and alternative communication in children with down syndrome

Introduction

Individuals with Down syndrome (DS) often exhibit a severe speech impairment, with important consequences on language intelligibility. For these cases, the use of Augmentative Alternative Communication instruments, that increase an individual's communication abilities, becomes crucial. Talkitt is a mobile application created by Voiceitt Company, exploiting speech recognition technology and artificial intelligence models to translate in real-time unintelligible sounds into clear words, allowing individuals with language production impairment to verbally communicate in real-time.

Methods

The study evaluated the usability and satisfaction related to the Talkitt application use, as well as effects on adapted behavior and communication, of participants with DS. A final number of 23 individuals with DS, aged 5.54 to 28.9 years, participated in this study and completed 6 months of training. The application was trained to consistently recognize at least 20 different unintelligible words (e.g., nouns and/or short phrases)/person.

Results

Results revealed good usability and high levels of satisfaction related to the application use. Moreover, we registered improvement in linguistic abilities, particularly naming.

Discussion

These results paves the road for a potential role of Talkitt application as a supportive and rehabilitative tool for DS.

Word prediction using closely and moderately related verbs in Down syndrome

People with Down syndrome (DS) have several difficulties in language learning, and one of the areas most affected is language production. Theoretical frameworks argue that prediction depends on the production system. Yet, people with DS can predict upcoming nouns using semantically related verbs. Possibly, prediction skills in people with DS are driven by their associative mechanism rather than by the prediction mechanism based on the production system. This study explores prediction mechanisms in people with DS and their relationship with production skills. Three groups were evaluated in a preferential-looking task: young adults, children with DS, and a typically developing control group paired by sex and mental age. Participants saw two images, a target and a distractor. They also heard a sentence in one of the three conditions: with a verb that was closely related to the object (e.g., "The woman read the book"), with a verb that was moderately related to the object (e.g., "My uncle waited for the bus"), or with a verb that was unrelated to the object (e.g., "My sister threw a broom"). Their productive vocabulary was then measured. In the young adult and typically developing groups, the results showed prediction in sentences with highly and moderately related verbs. Participants with DS, however, showed prediction skills only in the highly related context. There was no influence of chronological age, mental age, or production on prediction skills. These results indicate that people with DS base prediction mainly on associative mechanisms and they have difficulty in generating top-down predictions.

Morphosyntactic abilities in young children with Down syndrome: Evidence from the Greek language

Down syndrome is the most common genetic syndrome of intellectual disabilities with a distinct linguistic profile. Language research so far has come mainly from the English language, a language with different syntax and morphology from many other languages, including Greek, indicating a paucity of research findings in the Greek language. Given the rich morphology and distinct syntactic characteristics of the Greek language, the present study evaluated the performance of children with Down syndrome (N = 45) who are native Greek speakers in syntax and morphology and compared it with the performance of children with typical development (N = 45) matched for chronological age. The paper also analysed the items of each task in terms of the performance of the two groups in subject-verb agreement, noun conversion from singular to plural, and verb conversion from present to past and future tenses. All children were tested in four subscales of a standardized test, including morphosyntactic comprehension, morphosyntactic completion and articulation (parts 1 and 2). The results showed that children with Down syndrome lag behind in syntax and morphology compared with children of typical development and present difficulties in specific aspects of morphology and syntax inherent in the Greek language. WHAT THIS PAPER ADDS: What is already known on this subject Morphosyntactic skills are severely impaired in Down syndrome, and research so far has come mainly from the English language, a language with different syntax and morphology from many other languages. What this paper adds to existing knowledge This research adds more information about morphosyntactic skills in children with Down syndrome compared with typically developing children in the Greek language, a language with rich morphology and syntax. What are the potential or actual clinical implications of this work? Children with Down syndrome face difficulties in morphosyntactic skills in the Greek language, especially in subject-verb agreement and in converting nouns from singular to plural.

Speech production accuracy in children with Down syndrome: relationships with hearing, language, and reading ability and change in speech production accuracy over time

BACKGROUND

This study examines speech production accuracy in children with Down syndrome and concurrent relationships with hearing, language and reading ability. It also examines change in speech production accuracy over a 21-month period.

METHODS

A group of 50 children with Down syndrome (aged 5-10 years) completed measures of speech accuracy, non-verbal IQ, reading (single-word reading, letter-sound knowledge and phoneme blending) and language (expressive and receptive vocabulary and receptive grammar). Hearing was assessed by parental report. Speech accuracy was reassessed 21 months later.

RESULTS

Although there was considerable variability in the sample, speech was characterised by high levels of errors. There were no effects of gender, hearing status or non-verbal IQ on speech production accuracy. In contrast, speech production accuracy was significantly related to age and to measures of receptive vocabulary, phoneme blending and word reading. There was no significant improvement in speech production accuracy over time.

CONCLUSIONS

Children with Down syndrome experience difficulties producing accurate sounds in speech. These difficulties are related to age and to vocabulary and reading skills and persist over time, highlighting the need for intensive targeted speech intervention in this group of children.

Capacity of the CCC-2 to Discriminate ASD from Other Neurodevelopmental Disorders

The Children’s Communication Checklist (CCC-2) has demonstrated its usefulness as an instrument to assess discrepancies between the use of structural dimensions of language and the pragmatic and sociointeractive uses of language. The aims of the present paper are: (1) to test the capacity of the Galician adaptation of the CCC-2 to discriminate the linguistic profiles of children with different disorders and (2) to test whether the capacity of the CCC-2 to discriminate the linguistic abilities of children with different disorders is the same at different ages: earlier development and later development. The sample is of 117 children previously diagnosed with different disorders: autism spectrum disorder (ASD), developmental language disorder (DLD), attention deficit with hyperactivity disorder (ADHD), Down syndrome children (DS) and typically developing children (TD). The children were divided into two different age groups: from 4 to 6 and from 7 to 16 years of age. The results indicate that the Galician CCC-2 (1) accurately identified children with and without communicative impairments, (2) distinguished between profiles with a predominance of pragmatic (ASD and ADHD) and structural disorders (DS and DLD) and (3) distinguished between different profiles of pragmatic impairment. The CCC-2 equally identified these profiles at both earlier and later ages. The Galician CCC-2 seems to be a useful instrument for differentiating among different clinical groups and for assessing pragmatic disorders from an early age, which can be valuable for planning early intervention.

Assessing Phonological Profiles in Children and Adolescents With Down Syndrome: The Effect of Elicitation Methods

In the context of comparing linguistic profiles across neurodevelopmental disorders, Down syndrome (DS) has captured growing attention for its uneven profile. Although specific weaknesses in grammatical and phonological processing have been reported, research evidence on phonological development remains scarce, particularly beyond early childhood. The purpose of this study was to explore the phonological profiles of children and adolescents with Down syndrome. The profiles were based on the frequency and relative proportion of the processes observed by classes, and they were compared to those of typically developing preschool children of similar verbal age. A complementary goal was to assess the effect of two different methods of elicitation: a test of articulation and spontaneous speech sampling. Finally, intergroup and intragroup differences in full match percentages between three positions at syllable-level (complex onset, medial coda, and final coda) were assessed. The results of the present study confirmed that the frequency of phonological processes in children and adolescents with DS is atypically high and is above what is expected for lexical age and at the same level as grammatical age. Highly increased frequency of processes, consistent in all kinds of processes and positions at the syllable-level, and asynchronous with verbal age and mental age suggest atypical developmental trajectories of phonological development in the Down syndrome population.

Auditory-Perceptual Features of Speech in Children and Adults With Down Syndrome: A Speech Profile Analysis

Purpose The aim of this study was to determine how the speech disorder profiles in Down syndrome (DS) relate to reduced intelligibility, atypical overall quality, and impairments in the subsystems of speech production (phonation, articulation, resonance, and prosody). Method Auditory-perceptual ratings of intelligibility, overall quality, and features associated with the subsystems of speech production were obtained from recordings of 79 children and adults with DS. Ratings were made for sustained vowels (62 of 79 speakers) and short sentences (79 speakers). The data were analyzed to determine the severity of the affected features in each speaking task and to detect patterns in the group data by means of principal components analysis. Results Reduced intelligibility was noted in 90% of the speakers, and atypical overall speech quality was noted in 100%. Affected speech features were distributed across the speech production subsystems. Principal components analysis revealed four components each for the vowel and sentence tasks, showing that individuals with DS are not homogeneous in the features of their speech disorder. Discussion The speech disorder in DS is complex in its perceptual features and reflects impairments across the subsystems of speech production, but the pattern is not uniform across individuals, indicating that attention must be given to individual variation in designing treatments.

A meta-analysis of prosody in autism, Williams syndrome, and Down syndrome

Prosody, the rhythm and melody of speech, is an important component of effective communication, and it is an area of difficulty for many populations who struggle with communication. This paper is a meta-analysis of nine studies (and two sets of unpublished data) that assessed prosody using the Profiling Elements of Prosody in Speech-Communication (PEPS-C; Peppé & McCann, 2003) in autism spectrum disorder, Williams syndrome, and Down syndrome. Our original goal was to include studies involving any neurodevelopmental disorder that is commonly associated with intellectual disability, yet our systematic search, which included three databases (i.e., PsychInfo, ERIC, and PubMed), only identified studies involving these three groups. To be included in the meta-analysis, studies had to include a group (n ≥ 3 participants) with a neurodevelopmental disorder commonly associated with intellectual disability and a typically developing comparison group matched on chronological age, nonverbal abilities, or verbal abilities. Studies also needed to report original data using the PEPS-C and be available in English. Study quality was assessed using a checklist adapted from Downes et al. (2016). Results revealed that prosodic form was a weakness for each etiology, while unique patterns of strengths and weaknesses were evident for prosodic functions. Groups with autism (n = 5), all classified as high-functioning or with Asperger's syndrome, exhibited weakness in emotional affect but some relative strengths with turn-end and focus tasks. Groups with Williams syndrome (n = 4) demonstrated weaknesses on phrase/sentence-level tasks and relative strengths on word-level tasks. Groups with Down syndrome (n = 2) had the greatest difficulty overall, though performance was better on receptive (vs. expressive) function tasks. By combining studies and related subtasks of the PEPS-C, we are able to more confidently generalize findings for each population and identify targets for intervention. However, given the limited number of studies identified, this paper also highlights the need for more research on prosody in intellectual disability.

Gesture Frequency and Function in Infants With Fragile X Syndrome and Infant Siblings of Children With Autism Spectrum Disorder

Purpose Infant siblings of children with autism spectrum disorder (ASIBs) and infants with fragile X syndrome (FXS) are both at risk for developing autism spectrum disorder (ASD) and communication disorders; however, very few studies have examined 1 of the earliest forms of intentional communication in infants from these groups: gestures. This study examined the frequency and function of gesture use across 12-month-old infant ASIBs, infants with FXS, and low-risk controls. Method Participants included 23 ASIBs who did not later meet diagnostic criteria for ASD, 18 infants with FXS, and 21 low-risk controls. Gestures were coded from a semistructured play-based interaction. Results Overall, infants with FXS displayed fewer gestures than low-risk infants, whereas ASIBs did not differ from the FXS or low-risk groups in overall gesture frequency. In terms of the communicative function of the gestures used, the FXS and ASIB groups displayed significantly fewer social interaction gestures than the low-risk controls, with large effect sizes. Conclusion This study contributes to scant knowledge of early communication phenotypes of infant ASIBs who do not meet criteria for ASD and infants with FXS. Results indicated that gesture function, not frequency, best discriminated at-risk infants from low-risk infants at 12 months of age. Findings have implications for the clinical evaluation and treatment of infants at high risk for ASD and communication disorders.

Auditory-Perceptual Speech Features in Children With Down Syndrome

Speech disorders occur commonly in individuals with Down syndrome (DS), although data regarding the auditory-perceptual speech features are limited. This descriptive study assessed 47 perceptual speech features during connected speech samples in 26 children with DS. The most severely affected speech features were: naturalness, imprecise consonants, hyponasality, speech rate, inappropriate silences, irregular vowels, prolonged intervals, overall loudness level, pitch level, aberrant oropharyngeal resonance, hoarse voice, reduced stress, and prolonged phonemes. These findings suggest that speech disorders in DS are due to distributed impairments involving voice, speech sound production, fluency, resonance, and prosody. These data contribute to the development of a profile of impairments in speakers with DS to guide future research and inform clinical assessment and treatment.

Use of electropalatography in the treatment of speech disorders in children with Down syndrome: a randomized controlled trial

BACKGROUND

Electropalatography (EPG) records details of the location and timing of tongue contacts with the hard palate during speech. It has been effective in treating articulation disorders that have failed to respond to conventional therapy approaches but, until now, its use with children and adolescents with intellectual/learning disabilities and speech disorders has been limited.

AIMS

To evaluate the usefulness of EPG in the treatment of speech production difficulties in children and adolescents with Down syndrome (DS) aged 8-18 years.

METHODS & PROCEDURES

A total of 27 children with DS were assessed on a range of cognitive and speech and language measures and underwent additional EPG assessment. Participants were randomly allocated to one of three age-matched groups receiving either EPG therapy, EPG-informed conventional therapy or 'treatment as usual' over a 12-week period. The speech of all children was assessed before therapy using the Diagnostic Evaluation of Articulation and Phonology (DEAP) and reassessed immediately post- and 3 and 6 months post-intervention to measure percentage consonants correct (PCC). EPG recordings were made of the DEAP assessment items at all time points. Per cent intelligibility was also calculated using the Children's Speech Intelligibility Measure (CSIM).

OUTCOMES & RESULTS

Gains in accuracy of production immediately post-therapy, as measured by PCC, were seen for all groups. Reassessment at 3 and 6 months post-therapy revealed that those who had received therapy based directly on EPG visual feedback were more likely to maintain and improve on these gains compared with the other groups. Statistical testing showed significant differences between groups in DEAP scores across time points, although the majority did not survive post-hoc evaluation. Intelligibility across time points, as measured by CSIM, was also highly variable within and between the three groups, but despite significant correlations between DEAP and CSIM at all time points, no statistically significant group differences emerged.

CONCLUSIONS & IMPLICATIONS

EPG was an effective intervention tool for improving speech production in many participants. This may be because it capitalizes on the relative strength of visual over auditory processing in this client group. The findings would seem to warrant an increased focus on addressing speech production difficulties in current therapy.

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.

Regular and irregular inflection in down syndrome - New evidence from German

The study aims to explore whether regular inflectional morphology is affected in children/adolescents with Down syndrome (DS). German past participle forms were elicited for ten regular and ten irregular inflected verbs as well as for five novel verbs. Data were collected from a group of 21 monolingual German children and adolescents with DS (chronological age M = 11;03 years) and a group of 21 typically developing monolingual German children (chronological age M = 4;03 years) matched in chronological age to the nonverbal mental age of the DS group (mental age DS group M = 4;05 years). Data analysis indicated that eight children/adolescents with DS displayed a deficit in acquiring the regular participle marker -t and in applying it as default inflection in German participle formation. In contrast, a group of 13 individuals with DS performed similar to the typically developing control children. They had successfully acquired the regular participle affix -t and readily applied it as default inflection to produce participles for irregular verbs and novel verbs. The data indicate that the acquisition of regular inflectional morphology is not outside the scope of individuals with DS and succeeded in many affected individuals. However, a substantial number of individuals with DS displayed a selective deficit with regular default inflection. The occurrence of a selective deficit with regular default inflection in individuals with DS supports dualistic views to inflection, according to which two different cognitive components are involved in regular and irregular inflection that can be selectively affected in language disorders.

Verbal Agreement Inflection in German Children With Down Syndrome

PURPOSE

The study aims to explore whether finite verbal morphology is affected in children/adolescents with Down syndrome (DS), whether observed deficits in this domain are indicative of a delayed or deviant development, and whether they are due to phonetic/phonological problems or deficits in phonological short-term memory.

METHOD

An elicitation task on subject-verb agreement, a picture-naming task targeting stem-final consonants that also express verbal agreement, a nonword repetition task, and a test on grammar comprehension were conducted with 2 groups of monolingual German children: 32 children/adolescents with DS (chronological age M = 11;01 [years;months]) and a group of 16 typically developing children (chronological age M = 4;00) matched on nonverbal mental age.

RESULTS

Analyses reveal that a substantial number of children/adolescents with DS are impaired in marking verbal agreement and fail to reach an acquisition criterion. The production of word-final consonants succeeds, however, when these consonants do not express verbal agreement. Performance with verbal agreement and nonword repetition are related.

CONCLUSIONS

Data indicate that a substantial number of children/adolescents with DS display a deficit in verbal agreement inflection that cannot be attributed to phonetic/phonological problems. The influence of phonological short-term memory on the acquisition of subject-verb agreement has to be further explored.

Maternal Responsiveness to Gestures in Children With Down Syndrome

PURPOSE

This study compared gesture use in young children with Down syndrome (DS) and typical development (TD) as well as how mothers respond to child gestures based on child age and diagnosis.

METHOD

Twenty-two mother-child dyads with DS and 22 mother-child dyads with TD participated. The child participants were between 22 and 63 months and were matched on chronological age. We coded child gesture use and whether mothers recoded child gestures (i.e., provided a verbal translation) during naturalistic interactions.

RESULTS

The children with DS used more gestures than peers with TD. After controlling for expressive language ability, the two groups were not significantly different on child gesture use. Regardless of child diagnosis, mothers recoded approximately the same percentage of child gestures. There was a significant interaction between child diagnosis and child age when predicting the percentage of maternal gesture recodes; mothers of children with DS did not demonstrate differences in the percentage of maternal gesture recodes based on child age, but there was a negative relationship between the percentage of maternal gesture recodes and child age for the children with TD.

CONCLUSIONS

Young children with DS gesture more than chronological age-matched children with TD, therefore providing numerous opportunities for caregivers to recode child gestures and support language development. Early intervention should focus on increasing parent responsiveness to child gestures earlier in life in order to provide additional word-learning opportunities for children with DS.

Single-Word Speech Intelligibility in Children and Adults With Down Syndrome

PURPOSE

A single-word identification test was used to study speech production in children and adults with Down syndrome (DS) to determine the developmental pattern of speech intelligibility with an emphasis on vowels.

METHOD

Speech recordings were collected from 62 participants with DS aged 4-40 years and 25 typically developing participants aged 4-7 years. Panels of 5 adult lay listeners transcribed the speech recordings orthographically, and their responses were scored in comparison with the speakers' target words.

RESULTS

Speech intelligibility in persons with DS improved with age, especially between the ages of 4 and 16 years. Whereas consonants contribute to intelligibility, vowels also played an important role in reduced intelligibility with an apparent developmental difference in low versus high vowels, where the vowels /æ/ and/ɑ/ developed at a later age than /i/ and /u/. Interspeaker variability was large, with male individuals being generally less intelligible than female individuals and some adult men having very low intelligibility.

CONCLUSION

Results show age-related patterns in speech intelligibility in persons with DS and identify the contribution of dimensions of vowel production to intelligibility. The methods used clarify the phonetic basis of reduced intelligibility, with implications for assessment and treatment.

Core vocabulary of young children with Down syndrome

The aim of this study was to develop a core vocabulary list for young children with intellectual disabilities between 2 and 7 years of age because data from this population are lacking in core vocabulary literature. Children with Down syndrome are considered one of the most valid reference groups for researching developmental patterns in children with intellectual disabilities; therefore, spontaneous language samples of 30 Dutch children with Down syndrome were collected during three different activities with multiple communication partners (free play with parents, lunch- or snack-time at home or at school, and speech therapy sessions). Of these children, 19 used multimodal communication, primarily manual signs and speech. Functional word use in both modalities was transcribed. The 50 most frequently used core words accounted for 67.2% of total word use; 16 words comprised core vocabulary, based on commonality. These data are consistent with similar studies related to the core vocabularies of preschoolers and toddlers with typical development, although the number of nouns present on the core vocabulary list was higher for the children in the present study. This finding can be explained by manual sign use of the children with Down syndrome and is reflective of their expressive vocabulary ages.

Management of swallowing and communication difficulties in Down syndrome: A survey of speech-language pathologists

PURPOSE

To explore speech pathology services for people with Down syndrome across the lifespan.

METHOD

Speech-language pathologists (SLPs) working in Australia were invited to complete an online survey, which enquired about the speech pathology services they had provided to client/s with Down syndrome in the past 12 months. The data were analysed using descriptive statistics.

RESULT

A total of 390 SLPs completed the survey; 62% reported seeing a client with Down syndrome in the past 12 months. Most commonly, SLPs provided assessment and individual intervention for communication with varying levels of family involvement. The areas of dysphagia and/or communication addressed by SLPs, or in need of more services differed according to the age of the person with Down syndrome. SLPs reported a number of reasons why services were restricted.

CONCLUSION

There is a need to re-assess the way that SLPs currently provide services to people with Down syndrome. More research is needed to develop and evaluate treatment approaches that can be used to better address the needs of this population.

Characterization of ultrasonic vocalizations of Fragile X mice

Fragile X Syndrome (FXS) is the leading form of inherited intellectual disability. It is caused by the transcriptional silencing of FMR1, the gene which codes for the Fragile X Mental Retardation Protein (FMRP). Patients who have FXS exhibit numerous behavioral and cognitive impairments, such as attention-deficit/hyperactivity disorder, obsessive compulsive disorder, and autistic-like behaviors. In addition to these behavioral abnormalities, FXS patients have also been shown to exhibit various deficits in communication such as abnormal sentence structures, increased utterances, repetition of sounds and words, and reduced articulation. These deficits can dramatically hinder communication for FXS patients, exacerbating learning and cognition impairments while decreasing their quality of life. To examine the biological underpinnings of these communication abnormalities, studies have used a mouse model of the Fragile X Syndrome; however, these vocalization studies have resulted in inconsistent findings that often do not correlate with abnormalities observed in FXS patients. Interestingly, a detailed examination of frequency modulated vocalizations that are believed to be a better assessment of rodent communication has never been conducted. The following study used courtship separation to conduct a detailed examination of frequency modulated ultrasonic vocalizations (USV) in FXS mice. Our analyses of frequency modulated USVs demonstrated that adult FXS mice exhibited longer phrases and more motifs. Phrases are vocalizations consisting of multiple frequency modulated ultrasonic vocalizations, while motifs are repeated frequency modulated USV patterns. Fragile X mice had a higher proportion of "u" syllables in all USVs and phrases while their wildtype counterparts preferred isolated "h" syllables. Although the specific importance of these syllables towards communication deficits still needs to be evaluated, these findings in production of USVs are consistent with the repetitive and perseverative speech patterns observed in FXS patients. This study demonstrates that FXS mice can be used to study the underlying biological mechanism(s) mediating FXS vocalization abnormalities.

Articulation and acoustics of Kannada affricates: A case of geminate /ʧ/

Affricates have been observed to be problematic in phonological acquisition and disordered speech across languages, due to their relatively complex spatial and temporal articulatory patterns. Remediation of difficulties in the production of affricates requires understanding of how these sounds are typically produced. This study presents the first systematic articulatory and acoustic investigation of voiceless geminate affricate /ʧ/ in Kannada (a Dravidian language), compared to the palatal glide and the voiceless dental stop. Ultrasound data from 10 normal speakers from Mysore, India revealed that /ʧ/ is produced with the tongue shape intermediate between the palatal glide and the dental stop, and with the laminal constriction at the alveolar ridge. The observed articulatory differences are reflected in acoustic formant patterns of vowel transitions and stop/affricate bursts. Altogether, the results show that the Kannada consonant in question is an alveolopalatal affricate, supporting some of the previous descriptive phonetic accounts of the language and raising questions for further research on normal and disordered speech. The results and our survey of literature also suggest that affricates in South Asian languages tend to be phonetically variable and historically unstable compared to other consonant articulations.

How do families of children with Down syndrome perceive speech intelligibility in Turkey?

Childhood verbal apraxia has not been identified or treated sufficiently in children with Down syndrome but recent research has documented that symptoms of childhood verbal apraxia can be found in children with Down syndrome. But, it is not routinely diagnosed in this population. There is neither an assessment tool in Turkish nor any research on childhood verbal apraxia although there is a demand not only for children with Down syndrome but also for normally developing children. The study examined if it was possible to determine oral-motor difficulties and childhood verbal apraxia features in children with Down syndrome through a survey. The survey was a parental report measure. There were 329 surveys received. Results indicated that only 5.6% of children with Down syndrome were diagnosed with apraxia, even though many of the subject children displayed clinical features of childhood verbal apraxia. The most frequently reported symptoms of childhood verbal apraxia in literature were displayed by the children with Down syndrome in the study. Parents could identify childhood verbal apraxia symptoms using parent survey. This finding suggests that the survey can be developed that could serve as a screening tool for a possible childhood verbal apraxia diagnosis in Turkey.

Speech production in children with Down's syndrome: The effects of reading, naming and imitation

People with DS are known to have difficulties with expressive language, and often have difficulties with intelligibility. They often have stronger visual than verbal short-term memory skills and, therefore, reading has often been suggested as an intervention for speech and language in this population. However, there is as yet no firm evidence that reading can improve speech outcomes. This study aimed to compare reading, picture naming and repetition for the same 10 words, to identify if the speech of eight children with DS (aged 11-14 years) was more accurate, consistent and intelligible when reading. Results show that children were slightly, yet significantly, more accurate and intelligible when they read words compared with when they produced those words in naming or imitation conditions although the reduction in inconsistency was non-significant. The results of this small-scale study provide tentative support for previous claims about the benefits of reading for children with DS. The mechanisms behind a facilitatory effect of reading are considered, and directions are identified for future research.

Learning to read new words in individuals with Down syndrome: testing the role of phonological knowledge

This study examined the effect of word level phonological knowledge on learning to read new words in Down syndrome compared to typical development. Children were taught to read 12 nonwords, 6 of which were pre-trained on their phonology. The 16 individuals with Down syndrome aged 8-17 years were compared first to a group of 30 typically developing children aged 5-7 years matched for word reading and then to a subgroup of these children matched for decoding. There was a marginally significant effect for individuals with Down syndrome to benefit more from phonological pre-training than typically developing children matched for word reading but when compared to the decoding-matched subgroup, the two groups benefitted equally. We explain these findings in terms of partial decoding attempts being resolved by word level phonological knowledge and conclude that being familiar with the spoken form of a new word may help children when they attempt to read it. This may be particularly important for children with Down syndrome and other groups of children with weak decoding skills.

Ultrasonic vocalizations during male-female interaction in the mouse model of Down syndrome Ts65Dn

Down syndrome (DS) is the leading cause of genetically defined intellectual disability. Although speech and language impairments are salient features of this disorder, the nature of these phenotypes and the degree to which they are exacerbated by concomitant oromotor dysfunction and/or hearing deficit are poorly understood. Mouse models like Ts65Dn, the most extensively used DS animal model, have been critical to understanding the genetic and developmental mechanisms that contribute to intellectual disability. In the present study, we characterized the properties of the ultrasonic vocalizations (USVs) emitted by Ts65Dn males during courtship episodes with female partners. USVs emitted by mice in this setting have been proposed to have some basic correlation to human speech. Data were collected and analyzed from 22 Ts65Dn mice and 22 of their euploid littermates. We found that both the minimum and maximum peak frequencies of Ts65Dn calls were lower than those produced by euploid mice, whereas the mean individual duration of "down" and "complex" syllable types was significantly longer. Peak, minimal and maximal, and the fundamental frequencies of short syllables generated by Ts65Dn mice were lower compared to those by euploid mice. Finally, Ts65Dn males made fewer multiple jumps calls during courtship and the mean total duration of their "arc", "u", and "complex" syllables was longer. We discuss the human correlates to these findings, their translational potential, and the limitations of this approach. To our knowledge, this is the first characterization of differences between adult Ts65Dn and euploid control mice with respect to USVs.

Consonant and syllable complexity of toddlers with Down syndrome and mixed-aetiology developmental delays

This study examines whether speech sound production of toddlers with Down syndrome (DS) is on par with or more severely impaired than that of mental age (MA) peers with developmental delay due to aetiologies other than Down syndrome at two points within an 18-month period near the onset of spoken word production. The utterances of 26 children with DS, aged 24-33 months, with a mean MA of 14.3 months, originally studied by Fey et al. and Warren et al. were compared to those of a group of 22 children with similar intellectual and communication delay but no DS (NDS). Phonological measures included the size of the consonant inventory, syllable shape complexity, and number of communication acts with canonical vocalizations. At Time 1, the DS group performed as well as or better than the NDS group on these measures of speech production. At Time 2, 18 months later, the DS group was behind the NDS group on the same measures. Results extended the pattern of more severe impairment in children with DS than NDS peers commonly noted in expressive language to measures of phonological development.

Speech impairment in Down syndrome: a review

PURPOSE

This review summarizes research on disorders of speech production in Down syndrome (DS) for the purposes of informing clinical services and guiding future research.

METHOD

Review of the literature was based on searches using MEDLINE, Google Scholar, PsycINFO, and HighWire Press, as well as consideration of reference lists in retrieved documents (including online sources). Search terms emphasized functions related to voice, articulation, phonology, prosody, fluency, and intelligibility.

CONCLUSIONS

The following conclusions pertain to four major areas of review: voice, speech sounds, fluency and prosody, and intelligibility. The first major area is voice. Although a number of studies have reported on vocal abnormalities in DS, major questions remain about the nature and frequency of the phonatory disorder. Results of perceptual and acoustic studies have been mixed, making it difficult to draw firm conclusions or even to identify sensitive measures for future study. The second major area is speech sounds. Articulatory and phonological studies show that speech patterns in DS are a combination of delayed development and errors not seen in typical development. Delayed (i.e., developmental) and disordered (i.e., nondevelopmental) patterns are evident by the age of about 3 years, although DS-related abnormalities possibly appear earlier, even in infant babbling. The third major area is fluency and prosody. Stuttering and/or cluttering occur in DS at rates of 10%-45%, compared with about 1% in the general population. Research also points to significant disturbances in prosody. The fourth major area is intelligibility. Studies consistently show marked limitations in this area, but only recently has the research gone beyond simple rating scales.

The benefit of orthographic support for oral vocabulary learning in children with Down syndrome

Children with Down syndrome typically have weaknesses in oral language, but it has been suggested that this domain may benefit from learning to read. Amongst oral language skills, vocabulary is a relative strength, although there is some evidence of difficulties in learning the phonological form of spoken words. This study investigated the effect of orthographic support on spoken word learning with seventeen children with Down syndrome aged seven to sixteen years and twenty-seven typically developing children aged five to seven years matched for reading ability. Ten spoken nonwords were paired with novel pictures; for half the nonwords the written form was also present. The spoken word learning of both groups did not differ and benefited to the same extent from the presence of the written word. This suggests that compared to reading-matched typically developing children, children with Down syndrome are not specifically impaired in phonological learning and benefit equally from orthographic support.

Cognitive, environmental, and linguistic predictors of syntax in fragile X syndrome and Down syndrome

PURPOSE

To examine which cognitive, environmental, and speech-language variables predict expressive syntax in boys with fragile X syndrome (FXS), boys with Down syndrome (DS), and typically developing (TD) boys, and whether predictive relationships differed by group.

METHOD

We obtained Index of Productive Syntax ( Scarborough, 1990) scores for 18 boys with FXS only, 20 boys with both FXS and an autism spectrum disorder, 27 boys with DS, and 25 younger TD boys of similar nonverbal mental age. Predictors included group (diagnosis), nonverbal cognition, phonological working memory (PWM), maternal education, speech intelligibility, and expressive vocabulary. The research questions were addressed via hierarchical linear regression.

RESULTS

Diagnostic group, nonverbal cognition, and PWM predicted 56% of the variance in syntactic ability, with approximately three-fourths of the predicted variance explained by group membership alone. The other factors did not contribute any additional significant variance in this final model. There was no evidence that predictor effects differed by group.

CONCLUSIONS

Nonverbal cognition and PWM have an effect on expressive syntax beyond that of diagnostic group. These effects are estimated to be the same in boys with FXS, boys with DS, and TD boys. Explanations for residual variance and the relative role of different predictors are discussed.

Language development in school-age girls with fragile X syndrome

BACKGROUND

Girls with fragile X syndrome (FXS) have a wide range of cognitive and language abilities. The range of language outcomes experienced by girls with FXS, however, has been relatively unexplored. The purpose of this exploratory study was to examine receptive and expressive language, with a focus on vocabulary and syntax, in a group of school-age girls with FXS.

METHOD

Twenty-one girls with FXS aged 7-15 years participated in the study. The girls completed a receptive vocabulary test, non-verbal IQ test and an expressive language sample.

RESULTS

The mean IQ for this group of girls was at the cut-off for intellectual disability. Vocabulary was an area of strength relative to non-verbal cognition. Age and non-verbal IQ were significant predictors of vocabulary performance.

CONCLUSIONS

The data suggest that a substantial portion of the sample would qualify for speech and language services. This study highlights the need for continued research in the area of language and cognitive development in girls with the full mutation of fragile X.

An EPG analysis of /t/ in young people with Down's syndrome

Many studies have pointed to impaired speech intelligibility in young people with Down's syndrome (DS). Some have attributed these problems to delayed phonological development, while others have identified disordered speech patterns, which could be related to a dyspraxic element in their speech. This study uses electropalatography (EPG) to examine the speech of 25 young people with DS, focusing on their production of the obstruent /t/. For the EPG analysis, participants produced the target obstruent in the word 'toe', repeated 10 times. An investigative analysis was carried out. A new descriptive taxonomy of EPG error patterns was developed and these errors were related to perceptually based transcriptions. The measures are discussed in relation to current knowledge of the anatomical and physiological characteristics of DS.

Narrative Skill in Boys with Fragile X Syndrome with and without Autism Spectrum Disorder

We examined recalled narratives of boys with fragile X syndrome with autism spectrum disorder (FXS-ASD; N=28) and without ASD (FXS-O; N=29), and compared them to those of boys with Down syndrome (DS; N=33) and typically developing boys (TD; N=39). Narratives were scored for mentions of macrostructural Story Grammar elements (Introduction, Relationship, Initiating Events, Internal Response, Attempts/Actions, and Ending). We found that narrative recall is predicted by short-term memory and nonverbal mental age levels in almost all groups (except TD), but not by expressive syntax or caregiver education. After adjusting for these covariates, there were no differences between the three groups with intellectual disability (ID). The FXS-ASD group, however, had significantly poorer performance than the TD group on the overall Story Grammar score, and both the FXS-O and FXS-ASD groups had lower Attempts/Actions scores than the TD group. We conclude that some form of narrative impairment may be associated with FXS, that this impairment may be shared by other forms of ID, and that the presence of ASD has a significantly detrimental effect on narrative recall.

Early-, middle-, and late-developing sounds in monolingual and bilingual children: an exploratory investigation

PURPOSE

To examine the accuracy of early-, middle-, and late-developing (EML) sounds in Spanish-English bilingual children and their monolingual peers.

METHOD

Twenty-four typically developing children, age 3-4 years, were included in this study: 8 bilingual Spanish-English-speaking children, 8 monolingual Spanish speakers, and 8 monolingual English speakers. Single-word speech samples were obtained to examine (a) differences on the accuracy of EML sounds between Spanish-English bilingual children and monolingual Spanish and monolingual English children and (b) the developmental trend on the accuracy of EML sounds within languages for Spanish-English bilingual children and monolingual Spanish and monolingual English children.

RESULTS

Findings support those of Shriberg (1993) for English-speaking children and suggest possible EML categories for monolingual Spanish-speaking children and bilingual Spanish-English-speaking children.

CONCLUSIONS

These exploratory findings indicate the need for longitudinal examination of EML categories with a larger cohort of children to observe similarities and differences between monolingual and bilingual development.

Integrating genomes, brain and behavior in the study of songbirds

Songbirds share some essential traits but are extraordinarily diverse, allowing comparative analyses aimed at identifying specific genotype-phenotype associations. This diversity encompasses traits like vocal communication and complex social behaviors that are of great interest to humans, but that are not well represented in other accessible research organisms. Many songbirds are readily observable in nature and thus afford unique insight into the links between environment and organism. The distinctive organization of the songbird brain will facilitate analysis of genomic links to brain and behavior. Access to the zebra finch genome sequence will, therefore, prompt new questions and provide the ability to answer those questions.

Electropalatographic therapy for children and young people with Down's syndrome

Articulation disorders in Down's syndrome (DS) are prevalent and often intractable. Individuals with DS generally prefer visual to auditory methods of learning and may therefore find it beneficial to be given a visual model during speech intervention, such as that provided by electropalatography (EPG). In this study, participants with Down's syndrome, aged 10:1 to 18:9, received 24 individualized therapy sessions using EPG. Simultaneous acoustic and EPG recordings were made pre- and post-intervention during 10 repetitions of a word list containing lingua-palatal consonants. Participants also completed the DEAP phonology sub-test at both time points. Post-treatment, all participants showed qualitative and quantifiable differences in EPG patterns and improvements in DEAP percentage consonants correct. EPG assessment and therapy appears a positive approach for identifying and improving articulatory patterns in children with DS.

A perceptual and electropalatographic study of /integral/ in young people with Down's syndrome

Speech production in young people with Down's syndrome has been found to be variable and inconsistent. Errors tend to be more in the production of sounds that typically develop later, for example, fricatives and affricates, rather than stops and nasals. It has been suggested that inconsistency in production is a result of a motor speech deficit. Late acquired fricatives such as /s/ and /integral/ are complex articulations, which may require more precise motor programming and may therefore show highly inconsistent productions. Other factors potentially affecting speech production in this population are abnormal palatal structure, hearing loss, and hypotonia. A group of 20 young people with Down's syndrome were recorded using Electropalatography (EPG), reading a wordlist containing the phrase 'a sheep'. The wordlist contained seven other phrases and was repeated 10 times. Eight typically developing, cognitively matched children and eight adults were also recorded producing the same data set. Articulatory (EPG pattern analysis) and perceptual analyses of the 10 productions of /integral/ were carried out. /integral/ production was found to be inconsistent in the young people with Down's syndrome, with more errors both in the auditory analysis and articulatory analysis than in the typical sample, which may be due to a motor programming or motor control problem. There were a greater number of errors in the EPG analysis than in the perceptual analysis. This suggests that some young people with DS were able to produce perceptually acceptable /integral/ with atypical EPG patterns. The use of typical, adult-modelled /integral/ EPG patterns in therapy may be inappropriate for some children with DS who present with atypical palatal structures.

Transcribing the speech of children with cochlear implants: clinical application of narrow phonetic transcriptions

PURPOSE

The phonological systems of children with cochlear implants may include segment inventories that contain both target and nontarget speech sounds. These children may not consistently follow phonological rules of the target language. These issues present a challenge for the clinical speech-language pathologist who uses phonetic transcriptions to evaluate speech production skills and to develop a plan of care. The purposes of this tutorial are to (a) identify issues associated with phonetic transcriptions of the speech of children with cochlear implants and (b) discuss implications for assessment.

METHOD

Narrow transcription data from an ongoing, longitudinal research study were catalogued and reviewed. Study participants had at least 5 years of cochlear implant experience and used spoken American English as a primary means of communication. In this tutorial, selected phonetic symbols and phonetic phenomena are reviewed.

CONCLUSIONS

A set of principles for phonetic transcriptions is proposed. Narrow phonetic transcriptions that include all segment possibilities in the International Phonetic Alphabet and extensions for disordered speech are needed to capture the subtleties of the speech of children with cochlear implants. Narrow transcriptions also may play a key role in planning treatment.

Direct magnitude estimation of articulation rate in boys with fragile X syndrome

PURPOSE

To compare the perceived articulation rate of boys with fragile X syndrome (FXS) with that of chronologically age-matched (CA) boys and to determine segmental and/or prosodic factors that account for perceived rate.

METHOD

Ten listeners used direct magnitude estimation procedures to judge the articulation rates of 7 boys with FXS only, 5 boys with FXS and a diagnosis of autism spectrum disorder (ASD), and 12 CA boys during sentence repetition. Sentences had similar articulation rates in syllables per second as determined acoustically. Four segmental/prosodic factors were used to predict perceived rate: (a) percentage consonants correct, (b) overall fundamental frequency (F(0)) level, (c) sentence-final F(0) drop, and (d) acoustically determined articulation rate with the final word of the sentence excluded.

RESULTS

Boys with FXS and ASD were judged to talk faster than CA controls. Multiple linear regression indicated that articulation rate with the final word of the sentence excluded and sentence-final F(0) drop accounted for 91% of the variance for perceived rate.

CONCLUSIONS

Descriptions of speakers with FXS as having fast and/or fluctuating articulation rates may be influenced by autism status. Also, atypical sentence-final prosody may be related to perceived rate in boys with FXS and ASD.

Phonological accuracy and intelligibility in connected speech of boys with fragile X syndrome or Down syndrome

PURPOSE

To compare the phonological accuracy and speech intelligibility of boys with fragile X syndrome with autism spectrum disorder (FXS-ASD), fragile X syndrome only (FXS-O), Down syndrome (DS), and typically developing (TD) boys.

METHOD

Participants were 32 boys with FXS-O (3-14 years), 31 with FXS-ASD (5-15 years), 34 with DS (4-16 years), and 45 TD boys of similar nonverbal mental age. We used connected speech samples to compute measures of phonological accuracy, phonological process occurrence, and intelligibility.

RESULTS

The boys with FXS, regardless of autism status, did not differ from TD boys on phonological accuracy and phonological process occurrence but produced fewer intelligible words than did TD boys. The boys with DS scored lower on measures of phonological accuracy and occurrence of phonological processes than all other groups and used fewer intelligible words than did TD boys. The boys with FXS and the boys with DS did not differ on measures of intelligibility.

CONCLUSIONS

Boys with FXS, regardless of autism status, exhibited phonological characteristics similar to those of younger TD children but were less intelligible in connected speech. Boys with DS showed greater delays in all phonological measures than the boys with FXS and the TD boys.

The use of electropalatography (EPG) in the assessment and treatment of motor speech disorders in children with Down's syndrome: evidence from two case studies

BACKGROUND

Many children experience significant difficulties in developing key aspects of speech. For some, these communication difficulties are compounded by co-occurring intellectual disabilities.

METHOD

This paper presents two case studies from a larger on-going longitudinal study of the effectiveness of using electropalatography (EPG) to address the intelligibility problems experienced by many children and young people with Down's syndrome (DS). EPG, an innovative computer-based tool for assessing and treating speech motor difficulties, enables the speaker to 'see' the placement of his or her tongue during speech and to attempt to correct any lingual palatal errors.

RESULTS

This visual supplementation of auditory feedback offers potential therapeutic benefits for children with intellectual disabilities, many of whom show relative strengths in visual vs. auditory and simultaneous vs. sequential processing. EPG also provides therapists with an objective measure of articulatory ability.

CONCLUSIONS

Findings from these two case studies demonstrate the potential utility of EPG in both the assessment and treatment of speech motor disorders in DS.

Intonation and Phonation in Young Adults with Down Syndrome

This paper investigates various aspects of intonation and phonation in young adults with Down syndrome. The speech of nine speakers with Down syndrome was analyzed acoustically for different aspects of intonation and phonation. The results of these analyses were compared to similar speech samples of nine typical speakers of Standard British English. The controls were matched for age and gender. Different aspects of speakers' individual pitch framework were analyzed, ie, organic and linguistic pitch ranges, voice compass, and declination. Phonation was investigated acoustically as maximum phonation time, jitter, and shimmer. The results suggest that speakers with Down syndrome exhibit normal respiratory capacity, a reduced organic pitch range, and a somewhat reduced linguistic pitch range. In terms of the melodic variation in the intonation patterns, a higher mean speaking fundamental frequency was found with generally a less melodious rendering of the intonation contours and a shallower declination. The analysis of phonation indicated reduced jitter, while shimmer did not deviate significantly from the control group. Although the observed deviations in the Down syndrome speakers are suggestive of lack of laryngeal control at the physiological level, it cannot be excluded at this stage that they may also reflect personality characteristics or the use of different linguistic strategies in implementing intonation patterns.

Interventions Aimed at Improving Child Language by Improving Maternal Responsivity

Maternal responsivity, or the ways in which mothers provide for, interact with, and respond to their children, helps to shape their children's development, including language development. In this chapter, we describe maternal responsivity as a multilevel construct with different measures appropriate for each level. Molar responsivity refers to aspects of interaction style such as affect that can best be measured with rating scales. Molecular responsivity refers to contingent maternal behaviors that occur in response to child behaviors; and are best reflected by the frequencies of occurrence of these contingent behaviors. Results of many studies have demonstrated that both molar and molecular responsivity are related to important child outcomes such as language development. Children of more responsive mothers tend to have better outcomes. Based on these findings, interventions aimed at improving maternal responsivity and thereby child language outcomes have been developed and investigated through a number of studies. Results have shown positive outcomes for maternal responsivity and lesser secondary benefits to child language outcomes. Some of the qualities that appear associated with better outcomes include timing the interventions to co-occur with specific developments in child behaviors, teaching over a span of approximately 10-12 sessions, and designing lessons to be culturally sensitive to individual families.

Expression of fragile X mental retardation protein within the vocal control system of developing and adult male zebra finches

Individuals with fragile X syndrome (FXS) are cognitively impaired and have marked speech delays and deficits. Our goal was to characterize expression of fragile X mental retardation protein (FMRP), encoded by Fmr1 fragile X mental retardation 1 gene or transcript (FMR1), in an animal model that learns to vocalize, namely the zebra finch Taeniopygia guttata (Tgu). We cloned and sequenced the zebra finch ortholog of FMR1 (TguFmr1) and developed an antibody that recognizes TguFmrp specifically. TguFmrp has structural features similar to its human ortholog FMRP. Because FXS patients exhibit sensorimotor deficits, we examined TguFmrp expression prior to, during, and after sensorimotor song learning in zebra finches. We found that TguFmrp is expressed throughout the brain and in four major song nuclei of the male zebra finch brain, primarily in neurons. Additionally, prior to sensorimotor learning, we observed elevated TguFmrp expression in the robust nucleus of the arcopallium (RA) of post-hatch day 30 males, compared with the surrounding telencephalon, suggesting a preparation for this stage of song learning. Finally, we observed variable TguFmrp expression in the RA of adolescent and adult males: in some males it was elevated and in others it was comparable to the surrounding telencephalon. In summary, we have characterized the zebra finch ortholog of FMRP and found elevated levels in the premotor nucleus RA at a key developmental stage for vocal learning.

Phonological patterns in the conversational speech of children with cochlear implants

In this descriptive, longitudinal study, phonological patterns (i.e., natural phonological processes) were examined in a set of conversational speech samples obtained from six young children fitted with cochlear implants. Both developmental and non-developmental patterns were observed. This is consistent with findings from previous studies of the speech of children with hearing loss who wear hearing aids. Several of the patterns found were also the same as those reported in previous studies of children with cochlear implants. One developmental pattern and two non-developmental patterns were significantly correlated with age demonstrating a decrease over time. Trends were evident in several other patterns suggesting possible directions for future investigations.

LEARNING OUTCOMES

The reader will be able to (1) differentiate developmental from non-developmental phonological patterns, (2) identify the patterns that can be seen in the speech of children fitted with cochlear implants, and (3) understand the direction of pattern occurrence over time in this population.

Syntactic complexity during conversation of boys with fragile X syndrome and Down syndrome

PURPOSE

This study compared the syntax of boys who have fragile X syndrome (FXS) with and without autism spectrum disorder (ASD) with that of (a) boys who have Down syndrome (DS) and (b) typically developing (TD) boys.

METHOD

Thirty-five boys with FXS only, 36 boys with FXS with ASD, 31 boys with DS, and 46 TD boys participated. Conversational language samples were evaluated for utterance length and syntactic complexity (i.e., Index of Productive Syntax; H. S. Scarborough, 1990).

RESULTS

After controlling for nonverbal mental age and maternal education levels, the 2 FXS groups did not differ in utterance length or syntactic complexity. The FXS groups and the DS group produced shorter, less complex utterances overall and less complex noun phrases, verb phrases, and sentence structures than did the TD boys. The FXS with ASD group and the DS group, but not the FXS-only group, produced less complex questions/negations than did the TD group. Compared with the DS group, both FXS groups produced longer, more complex utterances overall, but on the specific complexity measures, they scored higher only on questions/negations.

CONCLUSION

Boys with FXS and DS have distinctive language profiles. Although both groups demonstrated syntactic delays, boys with DS showed greater delays.

Speech fluency in fragile X syndrome

The present study investigated the dysfluencies in the speech of nine French speaking individuals with fragile X syndrome. Type, number, and loci of dysfluencies were analysed. The study confirms that dysfluencies are a common feature of the speech of individuals with fragile X syndrome but also indicates that the dysfluency pattern displayed is not identical to developmental stuttering. To what extent the pattern of dysfluency in individuals with fragile X syndrome is syndrome specific is not yet clear.

Discourse skills of boys with fragile X syndrome in comparison to boys with Down syndrome

PURPOSE

This study compared the conversational discourse skills of boys who have fragile X syndrome with and without autism spectrum disorder (ASD) with those of boys with Down syndrome and boys who are typically developing.

METHOD

Participants were boys who have fragile X syndrome with (n = 26) and without (n = 28) ASD, boys with Down syndrome (n = 29), and boys who are typically developing (n = 22). Turns during an examiner-child interaction consisting of structured and semistructured activities were coded for the boys' ability to maintain a topic of conversation and the frequency of perseveration.

RESULTS

The results revealed that boys who had both fragile X and ASD produced significantly more noncontingent discourse than did boys who had only fragile X, boys with Down syndrome, or typically developing boys. This finding was observed regardless of whether the topic was maintained or changed and whether the turn type was a response or initiation. Regardless of autism status, boys with fragile X used more perseveration than did boys in the other groups.

CONCLUSION

These findings suggest that some aspects of the conversational discourse difficulties attributed to fragile X syndrome may be a function of the high rate of comorbidity between fragile X and autism, whereas some difficulties may be characteristic of fragile X syndrome.