Signaling of noncomprehension in communication breakdowns in fragile X syndrome, Down syndrome, and autism spectrum disorder

The Association Between Mother's Descriptive Language and Children with Autism's Conversational Repair: A Moderated Mediation Analysis

This study tested the role of children with autism spectrum disorder (ASD)'s conversational expansion in mediating between mothers' descriptive language and children with ASD's conversational repair, and whether this mediation was moderated by the relative complexity of mother-child language. Videos of forty children with ASD engaging in various activities with their mothers were transcribed into language samples and then coded. Mediation analyses indicated that conversational expansion mediated the association between descriptive language and conversational repair. Moderated mediation analysis further indicated that the relative complexity of mother-child language moderated the relationship between descriptive language and conversational expansion, creating a conditional indirect effect. Although preliminary, the results of this study provide parents and practitioners with a new idea of language intervention strategies.

Associations Among Sex, Cognitive Ability, and Autism Symptoms in Individuals with Down Syndrome

This study explores sex-differences in (a) rates and profiles of autism symptoms as well as in (b) the contribution of intellectual quotient (IQ) to autism symptom presentation in Down syndrome (DS). Participants were 40 males and 38 females with DS, aged 6 to 23 years. Autism symptoms were rated through the Autism Diagnostic Observation Schedule-Second Edition (ADOS-2). Results show no sex differences in the ADOS-2 Calibrated Severity Scores (CSS). However, only females with DS who are classified as DS-Only have higher scores on verbal IQ than those classified as DS + autism. Furthermore, associations between IQ and all CSSs are found for females, but not for males. Findings suggest that verbal cognition may play differential roles for females and males with DS.

An Exploratory Study of Pragmatic Language Use Across Contexts With the Pragmatic Rating Scale-School Age Among Autistic Boys and Boys With Fragile X Syndrome Plus Autism

PURPOSE

Autistic boys and boys with co-occurring fragile X syndrome and autism spectrum disorder (FXS + ASD) demonstrate similar pragmatic language difficulties. The Pragmatic Rating Scale-School Age (PRS-SA) captures ecologically valid metrics of pragmatic language impairments in these populations. It is traditionally scored based on the Autism Diagnostic Observation Schedule (ADOS), which may limit the use of the PRS-SA more broadly in research and clinical contexts.

METHOD

This study evaluated the feasibility of the PRS-SA based on a shorter, semistructured conversational context compared to the ADOS in school-age autistic boys (n = 16) and boys with FXS + ASD (n = 16), matched on ASD traits. Differences across ADOS and conversational contexts and associations with ASD-related social difficulties were evaluated.

RESULTS

Findings revealed differences in PRS-SA scores between ADOS and conversational contexts, but only for the FXS + ASD group. Limited associations were observed between PRS-SA scores and ASD traits.

CONCLUSIONS

Results from this study indicate the feasibility of using the PRS-SA in a shorter conversational context than the ADOS to assess pragmatic language among autistic boys. For boys with FXS + ASD, contextual differences warrant careful consideration in future work.

Transactional relationships between maternal requesting and responsivity, adolescent compliance, and task demands in fragile X syndrome

BACKGROUND

Males with fragile X syndrome (FXS) may have difficulty with social communication and language in addition to behavioral concerns such as noncompliance to maternal requests. Mothers vary in how they pose requests to their children, and contextual demands may also be a factor in compliance. This study examined the relationships between maternal requesting behaviors, maternal responsivity, child compliance, and task demands in adolescent males with FXS.

METHODS

35 mother-son dyads completed three interactive tasks during in-home visits (puzzle, iPad games, snack). The adolescents also completed assessments of language and autism symptoms. The three interactive tasks were video-recorded, and behavior-by-behavior coding and transcription was completed.

RESULTS

Comparing between tasks, mothers requested a behavior most often during the snack task and used a higher proportion of indirect requests during the iPad task. Adolescents were largely compliant across tasks, with average compliance equal to 70%. Adolescent compliance was predicted by maternal request frequency such that mothers who used more requests had adolescent sons who were less compliant. Maternal responsivity was higher for mothers of adolescents with FXS-only compared to those with FXS and high autism symptoms.

CONCLUSIONS AND IMPLICATIONS

Task demands may have influenced maternal requesting, which in turn may have impacted adolescent compliance. Compliance with requests is important for both social and educational aspects of life, and further study of requesting and compliance in FXS is needed to identify effective teaching and behavioral intervention methods.

Pragmatic Profiles of Adults with Fragile X Syndrome and Williams Syndrome

Linguistic phenotypes of individuals with Fragile X (FXS) and Williams (WS) syndromes exhibit various degrees of pragmatic impairment, involving difficulties in social communication and in adapting to conversational principles. The goal of the present study was to explore syndrome-specific pragmatic profiles of adults with FXS and WS based on the assessment of the observance of Gricean maxims of conversation. The participants were 12 Spanish-speaking adults (6 FXS/6 WS), without a diagnosis of ASD, whose extensive naturalistic conversations (71,859 words) were transcribed and coded with the CHILDES/TALKBANK tools and the PREP-CORP pragmatic protocol. Violations of the maxims of conversation were analyzed, and indexes of cooperation and conversational response were obtained. Both groups showed reduced verbal production and repetitive dysfluencies; prominent features in the FXS profile were higher proportion of non-contingent language, perseverations of topic and form, and impulsive conversational responses; in the WS profile, salient characteristics were higher proportion of tangential utterances, reformulations, and conversational responses reflecting overly literal interpretation. Pragmatic profiles of violation of conversational maxims reflect specific communication skills impaired in adults with FXS and WS and raise the need for assessment and intervention methods that specifically address their social communication abilities.

Behavior Problems and Social Competence in Fragile X Syndrome: A Systematic Review

Fragile X syndrome (FXS) causes intellectual disability and is the known leading cause of autism. Common problems in FXS include behavior and social problems. Along with syndromic characteristics and autism comorbidity, environmental factors might influence these difficulties. This systematic review focuses on the last 20 years of studies concerning behavior and social problems in FXS, considering environmental and personal variables that might influence both problems. Three databases were reviewed, leading to fifty-one studies meeting the inclusion criteria. Attention deficit hyperactivity disorder (ADHD) problems remain the greatest behavior problems, with behavioral problems and social competence being stable during the 20 years. Some developmental trajectories might have changed due to higher methodological control, such as aggressive behavior and attention problems. The socialization trajectory from childhood to adolescence remains unclear. Comorbidity with autism in individuals with FXS increased behavior problems and worsened social competence profiles. At the same time, comparisons between individuals with comorbid FXS and autism and individuals with autism might help define the comorbid phenotype. Environmental factors and parental characteristics influenced behavior problems and social competence. Higher methodological control is needed in studies including autism symptomatology and parental characteristics. More studies comparing autism in FXS with idiopathic autism are needed to discern differences between conditions.

Comparing Early Pragmatics in Typically Developing Children and Children with Neurodevelopmental Disorders

This study examined the early pragmatic language skills in typically developing (TD) preschool-age children, children with language impairment (LI) and children with autism spectrum disorder (ASD). Two hundred and sixty-two TD children, 73 children with LI, and 16 children with ASD were compared on early pragmatics through direct assessment (DA). Post hoc analysis revealed that children in two clinical groups displayed significant pragmatic language deficits. Children in the ASD group who were older exhibited comparable degree of impairments as their LI peers, suggesting a relatively stagnant development of pragmatic language skills in children with ASD. Findings also supported the use of DA in identifying pragmatic language deficits, which have implications for the adoption of this assessment approach in clinical settings.

The Phenotypic Profile Associated With the FMR1 Premutation in Women: An Investigation of Clinical-Behavioral, Social-Cognitive, and Executive Abilities

The FMR1 gene in its premutation (PM) state has been linked to a range of clinical and subclinical phenotypes among FMR1 PM carriers, including some subclinical traits associated with autism spectrum disorder (ASD). This study attempted to further characterize the phenotypic profile associated with the FMR1 PM by studying a battery of assessments examining clinical-behavioral traits, social-cognitive, and executive abilities in women carrying the FMR1 PM, and associations with FMR1-related variability. Participants included 152 female FMR1 PM carriers and 75 female controls who were similar in age and IQ, and screened for neuromotor impairments or signs of fragile X-associated tremor/ataxia syndrome. The phenotypic battery included assessments of ASD-related personality and language (i.e., pragmatic) traits, symptoms of anxiety and depression, four different social-cognitive tasks that tapped the ability to read internal states and emotions based on different cues (e.g., facial expressions, biological motion, and complex social scenes), and a measure of executive function. Results revealed a complex phenotypic profile among the PM carrier group, where subtle differences were observed in pragmatic language, executive function, and social-cognitive tasks that involved evaluating basic emotions and trustworthiness. The PM carrier group also showed elevated rates of ASD-related personality traits. In contrast, PM carriers performed similarly to controls on social-cognitive tasks that involved reliance on faces and biological motion. The PM group did not differ from controls on self-reported depression or anxiety symptoms. Using latent profile analysis, we observed three distinct subgroups of PM carriers who varied considerably in their performance across tasks. Among PM carriers, CGG repeat length was a significant predictor of pragmatic language violations. Results suggest a nuanced phenotypic profile characterized by subtle differences in select clinical-behavioral, social-cognitive, and executive abilities associated with the FMR1 PM in women.

Autism spectrum disorder in females with fragile X syndrome: a systematic review and meta-analysis of prevalence

BACKGROUND

Whilst up to 60% of males with fragile X syndrome (FXS) meet criteria for autism spectrum disorder (ASD), the prevalence and nature of ASD in females with FXS remains unclear.

METHOD

A systematic literature search identified papers reporting ASD prevalence and/or symptomatology in females with FXS.

RESULTS AND CONCLUSION

Meta-analysis suggested that rates of ASD for females with FXS are reliably higher than for females in the general population (a random effects model estimated weighted average prevalence at 14%, 95% CI 13-18%). Whilst papers highlighted a number of social and repetitive difficulties for females with FXS, characteristic profiles of impairment are not clear. Possible associations between ASD traits and IQ, and between ASD and levels of fragile X mental retardation protein, are suggested, but data are equivocal.

Language in young females with fragile X syndrome: Influence on the neurocognitive profile and adaptive behavior

Fragile X syndrome (FXS) is the leading cause of inherited intellectual disability. The objective of this research is to analyze the relationship between linguistic functions and performance of the following neuropsychological functions: executive, quantitative reasoning, social perception, behavior, social skills, and adaptive behavior. A neuropsychological and behavioral evaluations were carried out with a group of 26 girls with FXS, and 14 girls without FXS as a control group, using standardized tests. The two groups were homogeneous in age and IQ. Significant differences were found between groups in the relationship between some language processes: inhibition, auditory working memory, cognitive flexibility, level of social adaptation, self-direction, conceptual adaptation, academic skills, leadership ability, theory of mind, and arithmetic. In the group of girls with FXS, it was found that different aspects of language influence some of the executive functions evaluated, in addition to some specific aspects of social perception, adaptive behavior, and quantitative reasoning, in different ways. Future research should incorporate the study of the influence of other cognitive variables such as visual perception and executive function on behavioral, social, and adaptive aspects to know the real influence of all the cognitive variables on the behavior of girls with FXS.

A Longitudinal Study of Parent-Child Interactions and Language Outcomes in Fragile X Syndrome and Other Neurodevelopmental Disorders

Difficulties with pragmatic language (i.e., language in social contexts, such as conversational ability) are a noted characteristic of the language profiles of both fragile X syndrome (FXS) and autism spectrum disorder (ASD), conditions which show significant phenotypic overlap. Understanding the origins and developmental course of pragmatic language problems in FXS and other developmental conditions associated with language impairment is a critical step for the development of targeted interventions to promote communicative competence across the lifespan. This study examined pragmatic language in the context of parent-child interactions in school-age children with FXS (who did and did not meet ASD criteria on the ADOS; n = 85), idiopathic ASD (n = 32), Down syndrome (DS; n = 38), and typical development (TD; n = 39), and their parents. Parent-child communicative interactions were examined across multiple contexts, across groups, and in relationship to pragmatic language outcomes assessed 2 years later. Results showed both overlapping and divergent patterns across the FXS-ASD and idiopathic ASD child and parent groups, and also highlighted key differences in pragmatic profiles based on situational context, with more pragmatic language difficulties occurring for both ASD groups in less structured interactions. Differences in parental language styles during parent-child interactions were associated with child language outcomes, likely reflecting the complex interplay of discourse style inherent to a parent, with the inevitable influence of child characteristics on parent language as well. Together, findings help delineate the dynamic and multifactorial nature of impaired pragmatic skills among children with FXS and other neurodevelopmental disorders associated with language impairment, with potential implications for the development of targeted interventions for pragmatic communication skills.

Language Development From Early Childhood to Adolescence in Youths With Fragile X Syndrome

Purpose The aim of this study was to investigate language growth in individuals with fragile X syndrome (FXS) from early childhood to adolescence and the influence of maternal responsivity on language growth. Method We conducted a longitudinal analysis of language development in 55 youths (44 males, 11 females) with FXS. Data collection spanned the ages of 11-216 months. We measured expressive and receptive vocabulary with standardized tests. The number of different words and mean length of utterance were obtained from language sample analyses of mother-child interactions. We also measured maternal comments (responsivity indicator) produced during the language samples and child nonverbal IQ. Results Growth models indicated that rates of number of different words and receptive vocabulary were related to maternal commenting. Mean length of utterance did not change significantly over time. Expressive vocabulary measured with a standardized test grew, but the growth was not related to maternal commenting. Nonverbal IQ was related to all language outcomes at age of 10 years and to changes over time in vocabulary. Visual analysis indicated that the highest scores on standardized tests were produced by girls; however, measures derived from language sample analyses appeared similar for boys and girls. Language models for boys only were similar to the total sample models with lower scores at age of 10 years for some outcomes. Conclusion Results of persistent language impairments for most youths with FXS suggest the need for continued, focused interventions aimed at improved language productions in addition to a responsive environment. Supplemental Material https://doi.org/10.23641/asha.13022825.

An Observational Study of Social Interaction Skills and Behaviors in Cornelia de Lange, Fragile X and Rubinstein-Taybi Syndromes

We directly assessed the broader aspects of sociability (social enjoyment, social motivation, social interaction skills and social discomfort) in individuals with Cornelia de Lange (CdLS), fragile X (FXS) and Rubinstein-Taybi syndromes (RTS), and their association with autism characteristics and chronological age in these groups. Individuals with FXS (p < 0.01) and RTS (p < 0.01) showed poorer quality of eye contact compared to individuals with CdLS. Individuals with FXS showed less person and more object attention than individuals with CdLS (p < 0.01). Associations between sociability and autism characteristics and chronological age differed between groups, which may indicate divergence in the development and aetiology of different components of sociability across these groups. Findings indicate that individuals with CdLS, FXS and RTS show unique profiles of sociability.

"Are We Done Yet?" Question-Asking in Boys With Fragile X Syndrome and Idiopathic Autism Spectrum Disorder

Purpose Question-asking serves as a tool to learn new information and is important in both academic and social settings. Boys with idiopathic autism spectrum disorder (ASD) and boys with fragile X syndrome and comorbid ASD (FXS + ASD) have similar social communication deficits, which may have downstream effects on their question-asking ability. This study examined question-asking in school-age boys with idiopathic ASD and FXS + ASD, including the role of ASD severity, expressive grammatical complexity (measured by mean length of utterance [MLU]), and IQ. Method Twenty-five boys with FXS + ASD and 21 boys with idiopathic ASD (ages 9-16 years) were included in this study. Autism Diagnostic Observation Schedule assessments were transcribed and coded for the frequency, function, and appropriateness of spontaneous questions asked. We examined group differences in these aspects of question-asking and relationships between question-asking and ASD severity, MLU, and IQ within each group. Results Boys with FXS + ASD asked more questions than boys with idiopathic ASD, although boys with idiopathic ASD asked a higher proportion of appropriate questions. Boys with idiopathic ASD also asked the examiner more personal questions than the boys with FXS + ASD. ASD severity and MLU were related to the proportion of clarification questions in FXS + ASD, and ASD severity was also related to the proportion of personal questions in this group. For the boys with idiopathic ASD, ASD severity was related to the total number of questions asked. Conclusions Our findings highlight similarities and differences between boys with FXS + ASD and idiopathic ASD in their spontaneous question production and indicate that ASD severity and grammatical language are differentially important for question-asking. This study has implications for targeted treatment in question-asking skills for boys with FXS + ASD and ASD.

Relations between Everyday Executive Functioning and Language in Youth with Down Syndrome and Youth with Autism Spectrum Disorder

Language and executive functioning are major impairments in many neurodevelopmental disorders, but little is known about the relations between these constructs, particularly using parent-report. Thus, the current research sought to examine relations between executive function and language in two groups - Down syndrome (DS; n=41; Mage = 11.2) and autism spectrum disorder (ASD; n=91; Mage = 7.7). Results were as follows: in DS, executive function predicted pragmatic, but not structural language after covarying for age, sex, and social functioning; in ASD, executive function predicted both. Findings highlight the interrelatedness of language and executive functioning and may have implications for intervention development.

Expressive language abilities of boys with idiopathic autism spectrum disorder and boys with fragile X syndrome + autism spectrum disorder: Cross-context comparisons

BACKGROUND AND AIMS

Understanding the unique expressive language profiles of children with phenotypically similar, but distinct neurodevelopmental disorders, such as idiopathic autism spectrum disorder and fragile X syndrome with a co-diagnosis of autism spectrum disorder (fragile X syndrome + autism spectrum disorder), has both clinical and theoretical implications. However, comparative studies of these two clinical groups have been limited, and results have been inconsistent, partially as a result of different assessment methods being utilized. Thus, the current study compared the expressive language profiles of boys with idiopathic autism spectrum disorder and boys with fragile X syndrome + autism spectrum disorder and examined whether a similar linguistic profile emerged across different language sampling contexts: a semi-structured conversation and the Autism Diagnostic Observation Schedule.

METHODS

Eighteen boys with autism spectrum disorder (M_age  = 13.25 years) and 19 boys with fragile X syndrome + autism spectrum disorder (M_age  = 12.19 years), matched on autism spectrum disorder symptom severity and similar in terms of chronological age and mean length of utterance, participated in this study. Boys produced two language samples: one semi-structured conversation and one taken from the Autism Diagnostic Observation Schedule. Language samples were coded for talkativeness, lexical diversity, mean length of utterance, intelligibility, and repetitive or perseverative language.

RESULTS

Analyses revealed that boys with autism spectrum disorder produced language samples that were more lexically diverse and intelligible, and that included less topic perseveration compared to boys with fragile X syndrome + autism spectrum disorder. With regards to sampling context, boys in both groups were more talkative and produced longer and more intelligible utterances in their conversation sample compared to their Autism Diagnostic Observation Schedule sample. However, boys with autism spectrum disorder and fragile X syndrome + autism spectrum disorder used a higher proportion of topic perseveration during the conversation sample.

CONCLUSIONS

Overall, we found similarities as well as distinctions in the expressive language profiles of boys with fragile X syndrome + autism spectrum disorder and boys with idiopathic autism spectrum disorder. Moreover, the Autism Diagnostic Observation Schedule sample elicited a relatively different language profile than the conversation sample for boys in both groups.

IMPLICATIONS

These findings help to further elucidate the unique language phenotypes of boys with idiopathic autism spectrum disorder and boys with fragile X syndrome + autism spectrum disorder. Moreover, our findings indicate that multiple language samples may be needed to obtain a comprehensive account of a child's expressive language ability.

Longitudinal analysis of communication repair skills across three neurodevelopmental disabilities

BACKGROUND

This study is a longitudinal follow-up to prior work examining the important pragmatic skill of communication repair (i.e., the ability to respond effectively to a request for clarification of an unclear message) across three neurodevelopmental disabilities in which language skills are impaired: fragile X syndrome with and without autism spectrum disorder (FXS-ASD; FXS-O), idiopathic ASD (ASD-O), Down syndrome (DS) and controls with typical development (TD). Prior work examining communication repair skills at younger ages indicated impairments in boys with FXS-ASD and ASD-O, with females performing comparably with each other across groups.

AIMS

To characterize communication repair skills in young individuals with FXS-ASD, FXS-O, ASD-O, DS and TD, across groups and over development. A secondary aim included documenting sex differences in FXS (with and without ASD) and DS.

METHODS & PROCEDURES

Sixty young individuals with FXS-ASD (49 males, 11 females), 38 with FXS-O (13 males, 25 females), 38 with ASD-O (males only), 42 with DS (21 males, 21 females) and 41 with TD (21 males, 20 females) participated in the study, with a subsample reported on here who were retested at a second time point 2.7 years later on average. Participants completed a structured, picture-based task designed to assess the ability to repair breakdowns in communication. Participants' responses were compared across groups and sexes at the second time point, and interpreted with respect to previously published (Time 1) findings.

OUTCOMES & RESULTS

Key findings included that, with age, male groups (including those with FXS-ASD and ASD-O, who showed difficulty at Time 1) performed more comparably, decreasing their use of inappropriate responses, in spite of relatively little change observed in general cognitive or structural language abilities in the clinical groups. However, girls with FXS and DS became more non-responsive with age, and differences between boys and girls with FXS-ASD emerged over time as well.

CONCLUSIONS & IMPLICATIONS

Findings suggest that impairments in a critical pragmatic skill-the ability to repair communication breakdown-show significant change with age across three neurodevelopmental disabilities, with important sex-specific patterns. These developments were often observed in spite of a relative plateau in cognitive and language growth, suggesting that repair skills may be more malleable and therefore an excellent target for intervention. Findings not only inform the nature of pragmatic impairment across groups but also can importantly inform clinical practice, suggesting that clinicians should monitor pragmatic skills such as repairs throughout development and also consider the role of sex in clinical efforts.

Developmental Trajectory of Communication Repair in Children with Fragile X Syndrome

BACKGROUND & AIMS

The development of communicative competence requires both language and social skills. The ability to repair following a communication breakdown is critical for continued conversational interchange and to ensure comprehension of bids for communication. Repair demonstrates adequate language and social skills. Children with Fragile X Syndrome (FXS) have difficulty with language development and social skills, which may result in delays or deficits in repair. Repair may be additionally impaired in children with FXS and co-morbid autism. This study examined the development of repair in children with FXS from toddlerhood into middle childhood.

METHODS

Fifty-five children with FXS and their biological mothers participated. Data were collected during in-home visits approximately every 18 months. Videotaped mother-child interactions were collected, as well as standardized assessments of language, social skills, and autism symptomology.

RESULTS

Children with FXS acquired the ability to repair at 90% mastery by three-and-a-half years of age. Multilevel logistic regressions predicting probability of repair indicated marginally significant effects of mean length of utterance and number of different words, and significant effects of global social skills and autism symptomology. Effect sizes were small to moderate.

CONCLUSIONS

Ability to repair was measured in a naturalistic setting, which allowed children with FXS to utilize repairs in their daily interactions. Although children with FXS may have delayed development of repair relative to typically developing expectations, in general they nonetheless catch up and demonstrate a robust ability to repair by three-and-a-half years of age. However, this study provides evidence that individual differences in language and social skills may influence ability to repair in children with FXS. Finally, the relationship between autism symptoms and repair remains unclear, necessitating further exploration.

IMPLICATIONS

Given the noted delay in repair in young children with FXS, clinicians working with this population should target development of this skill as early as possible to maximize successful social interactions. This may be particularly necessary for children with FXS and co-morbid autism.

Requests for Communication Repair Produced by Typically Developing Preschool-Age Children

Purpose When breakdowns in communication occur, children may request a repair to increase understanding of the message. Unrepaired communication breakdowns may cause confusions, limit conversational exchanges, and restrict children's learning opportunities. Relatively little is known regarding the conditions under which children produce repair requests. Thus, this study examined the verbal communication repair requests produced by typically developing children and evaluated the relationship between children's repair requests and performance on a theory of mind task. Method Participants included 25 typically developing 4-year-old children who completed standardized, norm-referenced assessments of their expressive language, receptive language, and IQ; a theory of mind task; and a shared book reading task. In the shared book reading task, the examiner elicited child repair requests using questions and statements that contained insufficient information. Results Participants produced a statistically significant greater number of repair requests when presented with questions with insufficient information compared to statements with insufficient information ( p < .001). There were no differences in total repair requests between participants who passed or failed the theory of mind task ( p = .45). Conclusion Among preschool-age children, the shared book reading task provided a naturalistic medium that facilitated the examination of children's repair requests. Results from this study provide baseline information to which the repair requests produced by other populations, such as children with autism spectrum disorder, can be compared.

ASD Comorbidity in Fragile X Syndrome: Symptom Profile and Predictors of Symptom Severity in Adolescent and Young Adult Males

Many males with FXS meet criteria for ASD. This study was designed to (1) describe ASD symptoms in adolescent and young adult males with FXS (n = 44) and (2) evaluate the contributions to ASD severity of cognitive, language, and psychiatric factors, as well as FMRP (the protein deficient in FXS). A few ASD symptoms on the ADOS-2 were universal in the sample. There was less impairment in restricted and repetitive behaviors (RRB) than in the social affective (SA) domain. The best predictor of overall ASD severity and SA severity was expressive syntactic ability. RRB severity was best predicted by the psychiatric factors. Implications for clinical practice and for understanding the ASD comorbidity in FXS are discussed.

A Multimethod Analysis of Pragmatic Skills in Children and Adolescents With Fragile X Syndrome, Autism Spectrum Disorder, and Down Syndrome

PURPOSE

Pragmatic language skills are often impaired above and beyond general language delays in individuals with neurodevelopmental disabilities. This study used a multimethod approach to language sample analysis to characterize syndrome- and sex-specific profiles across different neurodevelopmental disabilities and to examine the congruency of 2 analysis techniques.

METHOD

Pragmatic skills of young males and females with fragile X syndrome with autism spectrum disorder (FXS-ASD, n = 61) and without autism spectrum disorder (FXS-O, n = 40), Down syndrome (DS, n = 42), and typical development (TD, n = 37) and males with idiopathic autism spectrum disorder only (ASD-O, n = 29) were compared using variables obtained from a detailed hand-coding system contrasted with similar variables obtained automatically from the language analysis program Systematic Analysis of Language Transcripts (SALT).

RESULTS

Noncontingent language and perseveration were characteristic of the pragmatic profiles of boys and girls with FXS-ASD and boys with ASD-O. Boys with ASD-O also initiated turns less often and were more nonresponsive than other groups, and girls with FXS-ASD were more nonresponsive than their male counterparts. Hand-coding and SALT methods were largely convergent with some exceptions.

CONCLUSION

Results suggest both similarities and differences in the pragmatic profiles observed across different neurodevelopmental disabilities, including idiopathic and FXS-associated cases of ASD, as well as an important sex difference in FXS-ASD. These findings and congruency between the 2 language sample analysis techniques together have important implications for assessment and intervention efforts.

Hippocampal deficits in neurodevelopmental disorders

Neurodevelopmental disorders result from impaired development or maturation of the central nervous system. Both genetic and environmental factors can contribute to the pathogenesis of these disorders; however, the exact causes are frequently complex and unclear. Individuals with neurodevelopmental disorders may have deficits with diverse manifestations, including challenges with sensory function, motor function, learning, memory, executive function, emotion, anxiety, and social ability. Although these functions are mediated by multiple brain regions, many of them are dependent on the hippocampus. Extensive research supports important roles of the mammalian hippocampus in learning and cognition. In addition, with its high levels of activity-dependent synaptic plasticity and lifelong neurogenesis, the hippocampus is sensitive to experience and exposure and susceptible to disease and injury. In this review, we first summarize hippocampal deficits seen in several human neurodevelopmental disorders, and then discuss hippocampal impairment including hippocampus-dependent behavioral deficits found in animal models of these neurodevelopmental disorders.

Specificity: A Phenotypic Comparison of Communication-Relevant Domains Between Youth With Down Syndrome and Fragile X Syndrome

Despite the shared presence of an intellectual disability (ID), there is a growing literature documenting important phenotypic differences between Down syndrome (DS) and fragile X syndrome (FXS). These conclusions, however, are based on a synthesis across studies, each of which typically includes only measures of a limited number of constructs, and with differing participant characteristics. Firmer conclusions regarding specific phenotypes require a single comprehensive multi-domain assessment of participants with the syndrome groups being well matched on chronological age (CA) and cognitive functioning. The current study was designed to fill this gap by assessing several important cognitive and behavioral domains relevant to communication, such as: structural language skills, false belief understanding, as well as pragmatics and behavioral difficulties, in 30 adolescents of both sexes with DS and 39 males with FXS, matched on CA and nonverbal (NV) cognition. After statistically controlling for NV cognition, we did not find significant syndrome differences in expressive and receptive structural language or false belief understanding. In contrast, participants with DS displayed less stereotyped language and fewer behavioral difficulties compared to males with FXS. Within-syndrome associations among the targeted domains are described. Finally, females with DS were less impaired than males with DS in almost all structural language domains, whereas no significant sex-related differences were observed in NV cognition, false belief understanding, pragmatics, or behavior. Clinical and methodological implications of the findings are discussed.

A Duck Wearing Boots?! Pragmatic Language Strategies for Repairing Communication Breakdowns Across Genetically Based Neurodevelopmental Disabilities

PURPOSE

The ability to repair breakdowns in communication is an important pragmatic language skill that helps to maintain clear and meaningful interactions. Examining this ability in genetically based neurodevelopmental disabilities in which pragmatics are affected can provide important information about the precise pragmatic skills impacted across different populations and also help to identify core mechanisms underlying pragmatic impairment that may inform tailored interventions.

METHOD

Individuals with idiopathic autism spectrum disorder (ASD-O; n = 40), fragile X syndrome with comorbid autism spectrum disorder (FXS-ASD; n = 62), FXS without ASD (FXS-O; n = 38), Down syndrome (DS; n = 43), and typical development (TD; n = 42) completed a picture description task in which an examiner prompted for clarification repeatedly to elicit communication repair attempts. Participants' response strategies were compared across diagnostic groups and by sex and examined in relationship to different cognitive abilities.

RESULTS

Relatively few group differences were observed in responses to requests for clarification overall. Males with ASD-O responded less to clarification requests than males with FXS-ASD and FXS-O, and males with FXS-ASD responded more inappropriately than males with ASD-O and DS. All male groups became less responsive to prompts for communication repair across the series of requests. Males with TD and FXS-ASD used less effective strategies than females.

CONCLUSION

All groups showed some proficiency in repairing communication breakdowns, although individuals with ASD-O and FXS-ASD demonstrated some key areas of difficulty, highlighting the importance of considering ASD symptomatology in assessment and treatment of males with FXS. Findings also suggest that, across groups, multiple requests for clarification may lead to disengagement from the interaction. Finally, correlated skills observed across groups could implicate different underlying skills related to communication repair abilities across groups.

Adaptive behavior in infants and toddlers with Down syndrome and fragile X syndrome

Individuals with Down syndrome (DS) experience deficits across all domains of adaptive functioning, however little is known about the emergence and age-related changes of these impairments compared to other neurogenetic disorders with similar intellectual disability impairments, such as fragile X syndrome (FXS). Adaptive behavior is key for optimal functioning in these populations. Participants aged 5-45 months comprised three age-matched groups, DS (n = 64), FXS (n = 69), and typically developing controls (TD; n = 69). Adaptive behavior was measured on the Vineland Adaptive Behavior Scales-II. Regressions were used to examine adaptive behavior in a cross-sectional design across age. DS infants and toddlers evidenced deficits across all areas of adaptive behaviors compared to the age-matched TD group, with clear impairments present in the first year of life. Motor skills were the area of greatest weakness in children with DS with significant impairment evident at 12 months of age that remained low through 3 years. Compared to age-matched children with FXS, children with DS showed initially lower standard scores at 12 months of age, but slower declines in standard scores across age, resulting in less impaired functioning at 36 months. This is the first study to compare adaptive behavior in infants and toddlers with DS to FXS, and demonstrate the phenotypic specificity of adaptive profiles in this diagnostic group. These findings provide evidence that adaptive behavior should be a major target of intervention in children with FXS and DS, and that these differences are potentially driven by unique etiologies attributable to each disorder.