ABSTRACT
Social anxiety is a common disorder that has negative impacts across multiple domains of function. Several clinical groups are at elevated risk for social anxiety, including those with fragile X syndrome and those with autism spectrum disorder. Measuring social anxiety in these clinical subgroups is fraught with challenge, however, given the complexity of social anxiety and measurement limitations that are particularly acute in persons with neurodevelopmental disorders. The over-arching aim of this study was to contribute to our understanding of the nature of social anxiety in fragile X syndrome and its association with autism spectrum disorder. To address this aim, we created a multi-faceted composite representing behavioral and biological aspects of social anxiety and examined differences in two adolescent and young adult-aged groups: 59 males with fragile X syndrome and 18 males with autism spectrum disorder. Results indicated a lower score on the multivariate composite for the males with fragile X syndrome relative to autism spectrum disorder but with evidence that traits of autism and social anxiety overlap. We conclude that measuring anxiety and autism traits in fragile X syndrome and autism spectrum disorder is complex with features that overlap and interact in a dynamic manner.
Subject(s)
Anxiety/psychology , Autism Spectrum Disorder/psychology , Fragile X Syndrome/psychology , Psychometrics/methods , Adolescent , Anxiety/genetics , Anxiety Disorders , Autism Spectrum Disorder/physiopathology , Communication , Cross-Sectional Studies , Facial Expression , Fragile X Mental Retardation Protein , Fragile X Syndrome/physiopathology , Humans , Hydrocortisone/analysis , Longitudinal Studies , Male , Reproducibility of Results , Saliva/chemistry , Social Behavior , Young AdultABSTRACT
BACKGROUND: Fragile X syndrome (FXS) and non-syndromic autism spectrum disorder (ASD) are distinct disorders with overlapping behavioral features. Both disorders are also highly associated with anxiety with abnormal physiological regulation implied mechanistically. Some reports suggest atypical hypothalamus-pituitary-adrenal (HPA) axis function, indexed via aberrant cortisol reactivity, in both FXS and non-syndromic ASD. However, no study has compared cortisol reactivity across these two disorders, or its relationship to ASD symptom severity. METHODS: Cortisol reactivity (prior to and following a day of assessments) was measured in 54 adolescent/young adult males with FXS contrasted to 15 males with non-syndromic ASD who had low cognitive abilities. RESULTS: Greater ASD symptom severity was related to increased cortisol reactivity and higher levels at the end of the day, but only in the non-syndromic ASD group. Elevated anxiety was associated with increased HPA activation in the group with FXS alone. CONCLUSIONS: Taken together, findings suggest a unique neuroendocrine profile that distinguishes adolescent/young adult males with FXS from those with non-syndromic ASD. Severity of ASD symptoms appears to be related to cortisol reactivity in the non-syndromic ASD sample, but not in FXS; while anxiety symptoms are associated with HPA activation in the FXS sample, but not in ASD despite a high prevalence of ASD, anxiety and physiological dysregulation characteristic in both populations.
Subject(s)
Anxiety , Autism Spectrum Disorder , Fragile X Syndrome , Hydrocortisone/metabolism , Hypothalamo-Hypophyseal System , Pituitary-Adrenal System , Adolescent , Adult , Anxiety/metabolism , Anxiety/physiopathology , Autism Spectrum Disorder/metabolism , Autism Spectrum Disorder/physiopathology , Fragile X Syndrome/metabolism , Fragile X Syndrome/physiopathology , Humans , Hypothalamo-Hypophyseal System/metabolism , Hypothalamo-Hypophyseal System/physiopathology , Male , Pituitary-Adrenal System/metabolism , Pituitary-Adrenal System/physiopathology , Saliva , Young AdultABSTRACT
PURPOSE: This study examined use of a speaker's direction of gaze during word learning by boys with fragile X syndrome (FXS), boys with nonsyndromic autism spectrum disorder (ASD), and typically developing (TD) boys. METHOD: A fast-mapping task with follow-in and discrepant labeling conditions was administered. We expected that the use of speaker gaze would lead to participants selecting as the referent of the novel label the object to which they attended in follow-in trials and the object to which the examiner attended in the discrepant labeling trials. Participants were school-aged boys with FXS (n=18) or ASD (n=18) matched on age, intelligence quotient, and nonverbal cognition and younger TD boys (n=18) matched on nonverbal cognition. RESULTS: All groups performed above chance in both conditions, although the TD boys performed closest to the expected pattern. Boys with FXS performed better during follow-in than in discrepant label trials, whereas TD boys and boys with ASD did equally well in both trial types. The type of trial administered first influenced subsequent responding. Error patterns also distinguished the groups. CONCLUSION: The ability to utilize a speaker's gaze during word learning is not as well developed in boys with FXS or nonsyndromic ASD as in TD boys of the same developmental level.
