Pragmatic Language in autism and fragile X syndrome: Genetic and clinical applications

Neural Processing of Speech Sounds in ASD and First-Degree Relatives

Efficient neural encoding of sound plays a critical role in speech and language, and when impaired, may have reverberating effects on communication skills. This study investigated disruptions to neural processing of temporal and spectral properties of speech in individuals with ASD and their parents and found evidence of inefficient temporal encoding of speech sounds in both groups. The ASD group further demonstrated less robust neural representation of spectral properties of speech sounds. Associations between neural processing of speech sounds and language-related abilities were evident in both groups. Parent-child associations were also detected in neural pitch processing. Together, results suggest that atypical neural processing of speech sounds is a heritable ingredient contributing to the ASD language phenotype.

A longitudinal investigation of pragmatic language across contexts in autism and related neurodevelopmental conditions

Background

Pragmatic language, or the use of language in social contexts, is a critical skill in daily life, supporting social interactions and the development of meaningful social relationships. Pragmatic language is universally impacted in autism spectrum disorder (ASD) and pragmatic deficits are also common in other neurodevelopmental conditions, particularly those related to ASD, such as fragile X syndrome (FXS). This study used a multi-method, longitudinal approach to characterize potentially unique pragmatic profiles across different neurodevelopmental disabilities, and across contexts that varied in degree of social demand. The utility of computational linguistic analyses, as an efficient tool for capturing pragmatic abilities, was also explored.

Methods

Pragmatic skills of boys with idiopathic ASD (ASD-O, n = 43), FXS with and without ASD (FXS-ASD, n = 57; FXS-O, n = 14), Down syndrome (DS, n = 22), and typical development (TD, n = 24) were compared using variables obtained from a standardized measure, narrative, and semi-naturalistic conversation at up to three time points.

Results

Pragmatic language was most significantly impacted among males with ASD-O and FXS-ASD across all three contexts, with more difficulties in the least structured context (conversation), and also some differences based on FXS comorbidity. Patterns of group differences were more nuanced for boys with FXS-O and DS, with context having less of an impact. Clinical groups demonstrated minimal changes in pragmatic skills with age, with some exceptions. Computational language measurement tools showed some utility for measuring pragmatic skills, but were not as successful as traditional methods at capturing differences between clinical groups.

Conclusion

Overlap and differences between ASD and other forms of neurodevelopmental disability in general, and between idiopathic and syndromic ASD in particular, have important implications for developing precisely tailored assessment and intervention approaches, consistent with a personalized medicine approach to clinical study and care in ASD.

Childhood Academic Performance: A Potential Marker of Genetic Liability to Autism

Autism spectrum disorder (ASD), a heritable neurodevelopmental disorder, confers genetic liability that is often expressed among relatives through subclinical, genetically-meaningful traits, or endophenotypes. For instance, relative to controls, parents of individuals with ASD differ in language-related skills, with differences emerging in childhood. To examine ASD-related endophenotypes, this study investigated developmental academic profiles among clinically unaffected siblings of individuals with ASD (n = 29). Lower performance in language-related skills among siblings mirrored previously-reported patterns among parents, which were also associated with greater subclinical ASD-related traits in themselves and their parents, and with greater symptom severity in their sibling with ASD. Findings demonstrated specific phenotypes, derived from standardized academic testing, that may represent childhood indicators of genetic liability to ASD in first-degree relatives.

Comparison of Linguistic Error Production in Conversational Language Among Boys With Fragile X Syndrome + Autism Spectrum Disorder and Autistic Boys

PURPOSE

Expressive language impairments are common among school-age boys with fragile X syndrome (FXS) and autistic boys. Given the high co-occurrence of autism spectrum disorder (ASD) among individuals with FXS, cross-condition comparisons can elucidate the specificity of such impairments as they relate to ASD. Language samples can provide fruitful information regarding individuals' grammatical skills in less structured formats relative to standardized measures. This study examined grammatical errors produced during a conversational language sample among 20 boys with FXS and co-occurring ASD (FXS + ASD) and 19 autistic boys matched on ASD severity.

METHOD

Language samples were coded for omissions and errors at the word and utterance levels. Participants' grammatical errors were also compared to separate mental age-matched and mean length of utterance-matched boys from a reference database.

RESULTS

Boys with FXS + ASD and autistic boys produced similar rates of errors across all categories. Relative to their matched comparison groups, boys with FXS + ASD and autistic boys produced significantly more omissions during conversation.

CONCLUSIONS

These findings suggest that omissions may be a unique grammatical marker associated with the ASD phenotype. Further examination of omissions across diagnostic groups would aid in clarifying the specificity of omissions in the language phenotype of ASD.

Brief Report: Linguistic Mazes and Perseverations in School-Age Boys with Fragile X Syndrome and Autism Spectrum Disorder and Relationships with Maternal Maze Use

Autism spectrum disorder (ASD) and fragile X syndrome (FXS) are neurodevelopmental disorders with overlapping pragmatic language impairments. Prior work suggests pragmatic language differences may run in families. This study examined specific pragmatic difficulties (i.e., linguistic mazes and perseverations) in boys (9-18 years) with idiopathic ASD (n = 26) and FXS+ASD (n = 29), and relationships with maternal maze use. Language samples were obtained separately for boys and mothers. Nonparametric analyses suggested that boys largely did not differ in their rates of mazes, but that boys with FXS+ASD exhibited more perseverations. Mazes were correlated between fragile X dyads. Maternal mazes were correlated with child perseverations among idiopathic ASD dyads. These findings have implications for the etiological significance of ASD-related language phenotypes.

Fragile X Premutation: Medications, Therapy and Lifestyle Advice

The fragile X premutation is characterized by 55–200 CGG repeats in the 5ʹ untranslated region of FMR1, whereas full fragile X mutation has greater than 200 repeats and full methylation, which manifests as fragile X syndrome (FXS). The premutation spectrum of clinical involvement includes fragile X-associated tremor/ataxia syndrome (FXTAS), fragile X-associated primary ovarian insufficiency (FXPOI), and fragile X-associated neuropsychiatric disorders (FXAND). In addition, premutation carriers also suffer from various other health problems such as endocrine abnormalities and autoimmune problems. In this paper, we have discussed different health issues faced by the carriers and interventions including medications, therapy and lifestyle changes that could improve their health.

Social communication in fragile X syndrome: pilot examination of the Brief Observation of Social Communication Change (BOSCC)

Background

Social communication is a key area of difficulty in fragile X syndrome (FXS) and there are not yet adequate outcome measurement tools. Appropriate outcome measures for FXS have been identified as a key area of research interest in order to evaluate future therapeutic trials. The Brief Observation of Social Communication Change-Minimally Verbal (BOSCC-MV), an outcome measure with strong psychometrics developed for autism spectrum disorder, has promise as an outcome measure to assess social communication change with FXS participants.

Methods

We examined the BOSCC-MV via central coders in this multi-site-trial to assess its appropriateness for FXS. Eighteen minimally verbal males ages 3–12 years were enrolled and assessed on two consecutive days and 7 participants completed a third visit 6 months later. We examined test-retest reliability, inter-rater reliability, and both convergent and divergent validity with standard clinical measures including the Autism Diagnostic and Observation Schedule-2, Vineland 3, Social Responsiveness Scale, and the Aberrant Behavior Checklist.

Results

The BOSCC-MV in FXS demonstrated strong inter-rater and test-retest reliability, comparable to previous trials in idiopathic ASD. Strong convergent validity was found with Autism Diagnostic Observation Schedule-2 and Vineland-3. Divergent validity was demonstrated between BOSCC-MV and unrelated measures.

Conclusions

The BOSCC-MV shows promise as a FXS social communication outcome measure, warranting further large-scale evaluation.

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.

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.

Language processing skills linked to FMR1 variation: A study of gaze-language coordination during rapid automatized naming among women with the FMR1 premutation

The FMR1 premutation (PM) is relatively common in the general population. Evidence suggests that PM carriers may exhibit subtle differences in specific cognitive and language abilities. This study examined potential mechanisms underlying such differences through the study of gaze and language coordination during a language processing task (rapid automatized naming; RAN) among female carriers of the FMR1 PM. RAN taps a complex set of underlying neuropsychological mechanisms, with breakdowns implicating processing disruptions in fundamental skills that support higher order language and executive functions, making RAN (and analysis of gaze/language coordination during RAN) a potentially powerful paradigm for revealing the phenotypic expression of the FMR1 PM. Forty-eight PM carriers and 56 controls completed RAN on an eye tracker, where they serially named arrays of numbers, letters, colors, and objects. Findings revealed a pattern of inefficient language processing in the PM group, including a greater number of eye fixations (namely, visual regressions) and reduced eye-voice span (i.e., the eyes' lead over the voice) relative to controls. Differences were driven by performance in the latter half of the RAN arrays, when working memory and processing load are the greatest, implicating executive skills. RAN deficits were associated with broader social-communicative difficulties among PM carriers, and with FMR1-related molecular genetic variation (higher CGG repeat length, lower activation ratio, and increased levels of the fragile X mental retardation protein; FMRP). Findings contribute to an understanding of the neurocognitive profile of PM carriers and indicate specific gene-behavior associations that implicate the role of the FMR1 gene in language-related processes.

Links between looking and speaking in autism and first-degree relatives: insights into the expression of genetic liability to autism

Background

Rapid automatized naming (RAN; naming of familiar items presented in an array) is a task that taps fundamental neurocognitive processes that are affected in a number of complex psychiatric conditions. Deficits in RAN have been repeatedly observed in autism spectrum disorder (ASD), and also among first-degree relatives, suggesting that RAN may tap features that index genetic liability to ASD. This study used eye tracking to examine neurocognitive mechanisms related to RAN performance in ASD and first-degree relatives, and investigated links to broader language and clinical-behavioral features.

Methods

Fifty-one individuals with ASD, biological parents of individuals with ASD (n = 133), and respective control groups (n = 45 ASD controls; 58 parent controls) completed RAN on an eye tracker. Variables included naming time, frequency of errors, and measures of eye movement during RAN (eye-voice span, number of fixations and refixations).

Results

Both the ASD and parent-ASD groups showed slower naming times, more errors, and atypical eye-movement patterns (e.g., increased fixations and refixations), relative to controls, with differences persisting after accounting for spousal resemblance. RAN ability and associated eye movement patterns were correlated with increased social-communicative impairment and increased repetitive behaviors in ASD. Longer RAN times and greater refixations in the parent-ASD group were driven by the subgroup who showed clinical-behavioral features of the broad autism phenotype (BAP). Finally, parent-child dyad correlations revealed associations between naming time and refixations in parents with the BAP and increased repetitive behaviors in their child with ASD.

Conclusions

Differences in RAN performance and associated eye movement patterns detected in ASD and in parents, and links to broader social-communicative abilities, clinical features, and parent-child associations, suggest that RAN-related abilities might constitute genetically meaningful neurocognitive markers that can help bridge connections between underlying biology and ASD symptomatology.

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.

The fragile X syndrome-autism comorbidity: what do we really know?

Autism spectrum disorder (ASD) is a common comorbid condition in people with fragile X syndrome (FXS). It has been assumed that ASD symptoms reflect the same underlying psychological and neurobiological impairments in both FXS and non-syndromic ASD, which has led to the claim that targeted pharmaceutical treatments that are efficacious for core symptoms of FXS are likely to be beneficial for non-syndromic ASD as well. In contrast, we present evidence from a variety of sources suggesting that there are important differences in ASD symptoms, behavioral and psychiatric correlates, and developmental trajectories between individuals with comorbid FXS and ASD and those with non-syndromic ASD. We also present evidence suggesting that social impairments may not distinguish individuals with FXS with and without ASD. Finally, we present data that demonstrate that the neurobiological substrates of the behavioral impairments, including those reflecting core ASD symptoms, are different in FXS and non-syndromic ASD. Together, these data suggest that there are clinically important differences between FXS and non-syndromic ASD that are masked by reliance on the categorical diagnosis of ASD. We argue for use of a symptom-based approach in future research, including studies designed to evaluate treatment efficacy.